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Safety By DesignSafety By DesignSafety By DesignSafety By
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251.
ssssaaaalllleeeessss@@@@ggggggggttttgggg....nnnneeeetttt
wwwwwwwwwwww....ggggggggttttgggg....nnnneeeetttt
Registered in the UK No. 6526912
GuardianGuardianGuardianGuardian
Ballistics Delivery SystemsBallistics Delivery SystemsBallistics
Delivery SystemsBallistics Delivery Systems
ART, VSS & SATART, VSS & SATART, VSS & SATART, VSS
& SAT FAQ HandbookFAQ HandbookFAQ HandbookFAQ Handbook
Rev HRev HRev HRev H
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Safety By DesignSafety By DesignSafety By DesignSafety By
Design
Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
CONTENTS
1 Foreword by John McGrath, Sales and Marketing Director
...............................................................................................2
2 Addressable Release Tool (ART)
......................................................................................................................................3
2.1 Why run an ART in the toolstring?
............................................................................................................................3
2.2 What are common applications for ARTs?
................................................................................................................4
2.3 What types of ART are
available?..............................................................................................................................4
2.4 How does the ART work?
..........................................................................................................................................5
2.5 Where can an ART be run in the toolstring?
..............................................................................................................6
2.6 What Guardian tools can I combine with an ART and in what
order?
.......................................................................7
2.7 How do I run multiple ARTs in the same string?
.......................................................................................................7
2.8 What head types are available?
..................................................................................................................................7
2.9 What ART equipment is required to perform a job?
..................................................................................................7
2.10 What does the ART look like electrically?
.................................................................................................................7
2.11 What track record does the ART have?
......................................................................................................................9
2.12 How many ARTs are in the field?
..............................................................................................................................9
2.13 With what tractors has the ART been run?
.................................................................................................................9
2.14 Has an ART ever been released inadvertently or
accidentally?..................................................................................9
2.15 Which service companies have run ARTs?
................................................................................................................9
2.16 Can the ART be used in wells containing H2S or CO2?
...........................................................................................10
2.17 What is the maximum perforating gun I can run with an ART?
...............................................................................10
2.18 What happens if the shooting line shorts after perforating can
I still release if the gun string becomes stuck? ....10 2.19 What
procedures do I need to be aware of before initiating an ART
release?
.........................................................11 2.20
What fishing grapple do I require for the ART-C?
...................................................................................................12
2.21 What fishing grapple do I require for the ART-H/T?
...............................................................................................13
2.22 What is the maximum ART load before, during and after release?
..........................................................................14
2.23 How do I release an ART?
.......................................................................................................................................14
2.24 What happens if there is a cable insulation or continuity
problem can I still release?
..........................................15 2.25 Can I reverse the
ART motor and reset the ART after release?
...............................................................................16
2.26 Why cant I reverse the ART motor?
.......................................................................................................................16
2.27 Can I release an ART at surface?
.............................................................................................................................16
2.28 Can I run and release the ART upside down?
..........................................................................................................16
2.29 How often should I service the ART?
......................................................................................................................17
2.30 How much weight do I need below the ART to enable a successful
release?
..........................................................17 2.31
How long does it take to re-build an ART-C/H tool?
...............................................................................................17
2.32 Do I need special training to service an ART?
.........................................................................................................17
2.33 Is Guardian able to provide ART maintenance training?
.........................................................................................17
2.34 Does Guardian provide ART servicing and tool repair?
..........................................................................................18
2.35 What tools do I require to re-build an ART-H/T tool?
.............................................................................................18
2.36 What spares do I require to rebuild an ART
tool?....................................................................................................18
2.37 What maintenance products are recommended for the re-build of
an ART tool?
....................................................18
3 ART Specifications
..........................................................................................................................................................20
4 ART Applications and Release Case Studies
...................................................................................................................21
5 Voltage Protection Modules (VPM)
................................................................................................................................23
5.1 Why run a VPM in the toolstring?
...........................................................................................................................23
5.2 For what applications would I use a VPM in my toolstring?
....................................................................................23
5.3 Where do I position the VPM in the toolstring?
.......................................................................................................24
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Safety By DesignSafety By DesignSafety By DesignSafety By
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
5.4 Is the VPM run above or below an ART?
................................................................................................................24
5.5 What is a VSS Voltage Sensing Switch?
...............................................................................................................24
5.6 Where should correlation tools be run above or below the VPM?
........................................................................24
5.7 What head types are available?
................................................................................................................................25
5.8 Can I obtain a VPM for a specific operation?
..........................................................................................................25
5.9 What additional equipment do I need to run a VPM-A/B/F?
...................................................................................26
5.10 What servicing equipment is required for the VPM-A/B/F?
....................................................................................26
5.11 Which VPM tool do I run to electrically disconnect the
downhole toolstring from the tractor?
..............................26 5.12 Can I run more than one VPM-G
in a
toolstring?.....................................................................................................28
5.13 What VPM-G equipment do I need?
........................................................................................................................28
5.14 What servicing equipment is required for the VPM-G?
...........................................................................................29
5.15 Are there additional safety procedures when running a VPM-G?
............................................................................29
5.16 What is the procedure to enter Tractor or Safe Mode?
..........................................................................................30
5.17 What is the procedure to enter Fire or Log Mode?
.................................................................................................30
5.18 What is the fault light LED for on the VCP surface control
panel?
.........................................................................30
5.19 What happens if the VPM surface control panel (VCP) is
switched off whilst the tractor is powered up? ..............31
5.20 What types of VPM are available?
...........................................................................................................................32
6 VPM Specification
...........................................................................................................................................................33
7 Shock Absorber Tool (SAT)
............................................................................................................................................34
7.1 Why run an SAT in the toolstring?
...........................................................................................................................34
7.2 What diameter tools are available?
..........................................................................................................................34
7.3 What load will a SAT take?
.....................................................................................................................................34
7.4 Is the SAT H2S rated?
..............................................................................................................................................34
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Safety By DesignSafety By DesignSafety By DesignSafety By
Design
Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
FIGURES
Figure 1-1 Sectional View of the ART-H - Addressable Release
Tool
..................................................................................4
Figure 2 ART Operting Instructions (inside lid of portable ACP)
............................................................................................5
Figure 2-2 - ACP Surface Control Panel
....................................................................................................................................6
Figure 2-3 - ART/ACP Electronic Block Diagram
....................................................................................................................8
Figure 2-4 - ART Downhole Electronics
...................................................................................................................................8
Figure 2-5 - ART-C (1 OTIS) Fishing Head
..........................................................................................................................12
Figure 2-6 - ART-H 1 3/16 OTIS Fishing Head
.......................................................................................................................13
Figure 2-7 - ART-H Fishing Head Assembly
...........................................................................................................................13
Figure 2-8 - ART-H Schematic - Before Release
.....................................................................................................................14
Figure 2-9 - ART-H Schematic- After Release
........................................................................................................................14
Figure 2-10 - Section of ART-H Fishing Head and Grapple System
.......................................................................................15
Figure 5-1 - Fuse Rating Time
.................................................................................................................................................26
Figure 5-2 - VPM-G Block
Diagram........................................................................................................................................28
Figure 5-3 VPM-A Control Panel (19 Rack-Mount)*
.........................................................................................................29
Figure 5-4 VPM-B Control Panel (Suit-Case)*
....................................................................................................................29
Figure 7-1 Shock Absorber Tool (SAT-A), 2 1/8
.................................................................................................................34
TABLES
Table 2-1 - Recommended Maintenance Products
...................................................................................................................19
Table 5-1 - VPM Toolstring Position
.......................................................................................................................................24
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Safety By DesignSafety By DesignSafety By DesignSafety By
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
Figure 1-1 Sectional View of the ART-H - Addressable Release
Tool
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Safety By DesignSafety By DesignSafety By DesignSafety By
Design
Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
1 Foreword by John McGrath, Sales and Marketing Director
The last two decades have seen a marked drive within the oil and
gas industry to improve well-site safety and increase oil and gas
recovery from developed and exploration wells. This impetus has led
to rapid advances in drilling technology, spearheaded by activities
in directional drilling and an increase in horizontal, or long
reach wells.
In this new and even more hostile world, traditional wireline
logging operations have adopted techniques such as coiled tubing,
pipe conveyed logging and more recently, downhole tractors. The
increase in demand for wireline operations in horizontal or highly
deviated wells has compounded existing problems in these types of
operation, namely the ability to guarantee successful release from
the cable head of a stuck toolstring (or tractor), and the ability
to prevent the high tractor voltages and currents from reaching
armed ballistic devices such as perforating guns or setting tools.
The above problems are especially apparent when running powered
downhole tractors in horizontal wells. However, it should also be
stated that they are not limited to horizontal wells, but can
equally occur in vertical or deviated holes.
In order to meet the global challenge of improved well-site
safety and to offer an alternative solution to costly rig lost-time
(fishing for broken cable, stuck logging tools, swollen guns or
partially set plugs), Guardian Global Technologies has developed a
range of innovative and complimentary downhole protection systems.
The products which make up these systems are designed to operate in
the sphere of deviated wells, tractor operations in horizontal
wells and general wireline applications, such as production logging
and perforating.
Controlled via a compact surface panel and robust telemetry
system, the Addressable Release Tool (ART) removes the uncertainty
involved in breaking the weak-point by using an electro-mechanical
system to achieve a controlled downhole release of a stuck
toolstring. Complementing the ART wireline applications is a range
of Voltage Protection Modules (VPM) that block or prevent unwanted
voltages and currents from damaging production logging tools or
accidentally detonating explosive wireline devices during
perforating or plug setting operations.
The VPM and ART range of safety products provide the ultimate in
downhole protection, since they operate as complementary tools. The
VPM acts as an electrical safety device during perforating and
production logging operations, while the ART provides a mechanical
safety system enabling the controlled release of stuck downhole
tools.
The purpose of this handbook is to provide concise information
on the operation and associated field applications of the ART and
VPM tools based on frequently asked questions (FAQs) received by
GGTs technical department. The booklet also provides information on
a number of field case studies.
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
2 Addressable Release Tool (ART)
2.1 Why run an ART in the toolstring?
The Addressable Release Tool (ART) is designed for use in high
deviation or horizontal wells and enables the wireline engineer to
affect a controlled release of all, or part of a stuck tool-string,
without having to break the weak-point. The ART allows the engineer
to employ the conventional method of attempting to free the stuck
toolstring by increasing the cable head tension to the maximum safe
pull. If the tool cannot be freed using this method, the engineer
can then use the controllable and safe option of activating the
ARTs unique electro-mechanical system to release the cable and head
from the stuck toolstring. This method improves wellsite safety and
reduces rig downtime by eliminating the inherent problems of
wireline operations in deviated wells. That is, the engineers
ability to work-down enough tension to break the weak-point at the
head, without parting the cable at surface or at some indeterminate
point in the well.
None of the ART product range uses explosives in its operation.
This both improves safety and allows selective (positive/negative)
perforating below the ART. More specific applications and benefits
are listed below.
a) Weak-points do not guarantee a clean fishing neck Personally
I dont trust mechanical weak points to give me a clean fishing neck
as Ive had it where there was still a strand of wire sticking out
of the head and we couldnt get the grapple on. We then had to run
an LIB to see the wire and then box it off before trying to fish
again. At that point we knew that we had a loose piece of wire at
the cable head. People are far happier to release an ART as they
are sure that they will get the worst part the cable, out of the
hole.
b) Weak points release over too large a range The range within
which weak points release is so large that you invariably get one
going way to the left of the bell curve and releasing early. This
makes you down rate your weak point further and limits what you can
do.
c) An ART release saves time and is safer When you pull the weak
point you have to barrier off the deck and have meetings and all
permits to do as you will be pulling a lot of tension and the wire
is going to spring back. It will generally take a few hours to get
all this organised and this is all downtime. As there is no real
over pull when you release an ART you can save hours here and have
a safer operation on deck.
d) The cable is worked too long with a weak point No one wants
to pull the weak point for the reasons stated above so they work
the tool for many hours and end up work hardening the cable over
the top sheave and it may then break there. What normally happens
though is that on a subsequent job when there is a large overpull
the cable breaks in the hole at the point where it was previously
work hardened. Ive had this happen more than once to me. Using and
ART saves a bunch of time and protects the cable for future
jobs.
e) You dont get stuck as often with an ART If you are tying a
100% weak point then you will have much more pull available as you
pull out of the well. At TD this may equate to 50-100% increase,
but you rarely get stuck on TD. Its generally at a nipple, WEG,
sliding sleeve etc. With a weak point you always only have a fixed
amount of pull regardless of where you are in the well. With an ART
the amount of pull that you have increases the shallower you get as
the weight of the cable is recovered as additional pull. The chart
below is part of our standard presentation and provides a clear
illustration. The blue line is the over pull that you get with a
standard weak point on 7/32 cable at 7,000m. The red line is the
over pull available at any particular depth using the ART with a
100% weak point and not working the cable more than 65% of it
tensile strength. The green line is the over pull if you pull
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
up to the cables tensile strength. Normally you would never do
this, but there may be a case where you still want to have this
option even if it does trash the cable. You dont have this option
with a weak point.
Figure 2-1 ART Advantage Chart
2.2 What are common applications for ARTs?
Release of stuck downhole tractors Release of partially set
plugs/packers Release of damaged gun strings (for example swelling)
Release of stuck production logging tools Planned and deliberate
release of a toolstring element in the well Applications in deep
wells, where stronger weak-points are required Pump down operations
where a string weak point is required to prevent guns being pumped
off the end of the line as
they pass as restriction.
2.3 What types of ART are available?
The ART-C has an OD of 1 11/16 and is rated to 15,000 psi and
177C (350F). The tool is primarily designed for use in conjunction
with production logging and data acquisition equipment. It has a
safe working load of two tonnes and can withstand a fishing load
(post-release) of ten tonnes. The ART-C uses a 1 OTIS fishing head
and utilises GGTs proprietary high voltage isolation electronics,
making it suitable for use with high voltage downhole operations
(tractors). The ART operation is controlled on surface using an ART
control panel (ACP), which is capable of controlling up to seven
ART-Cs in a toolstring.
The ART-H is a 2 1/8 tool diameter and is rated to 15,000 psi
and 177C (350F). The tool is designed for use in conjunction with
downhole-tractor devices where the controllable release of all or
part of a stuck tool-string, set plug or expanded gun string is
required. The tool is specifically intended for use above a
downhole tractor, but can also be deployed below. The tool can also
be deployed with electric-line equipped coiled tubing. The ART-H is
designed to withstand the high voltages used to drive downhole
tractors and is able to carry a maximum safe working load of three
tonnes and a fishing
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
load (post-release) of ten tonnes. The ART-H operation is
controlled on surface using the same ART control panel (ACP) as the
ART-C. Up to seven ART-Hs can be run in a toolstring
The 3 3/8 MRT is a multi-conductor (10) version of the ART for
use with open-hole logging equipment.
2.4 How does the ART work?
All ARTs use a downhole electro-mechanical system (grapple and
fishing head) to release from a stuck toolstring, and incorporate a
number of fail-safe mechanisms to prevent accidental release. The
engineer controls the ART operation using a surface control panel
(ACP), which communicates with the downhole tool on the wireline
cable via a robust digital telemetry system. When the decision has
been made to activate the ART and release from the stuck tool, the
surface control panel (ACP) is connected to the wireline cable,
which then establishes communication with the ART(s) in the
toolstring.
The engineer selects which ART is to be released, before arming
the ART; this confirms downhole communication and status. Once
armed, the release sequence can be activated by pushing the release
button on the ACP. The ACP signals the tool to switch on a downhole
motor which activates the release mechanism. This actuation enables
the upper portion of the ART to release from the fishing head
assembly. The engineer is able to check the progress of the
operation using LED status indicators and a display showing the ART
tool current. Note that the principle of operation of the ART-C is
the same as that of the ART-H, -T and -I, however the mechanical
details are different. For further details please review the ART
mechanical and electronic description in the associated
manuals.
Once released, a standard fishing neck remains to facilitate
further recovery operations. Due to the presence of O rings and
depending upon well pressure, approximately 100 pounds of cable
tension at the head is required to pull apart the upper and lower
section.
Figure 2-1 ART Operating Instructions (inside lid of portable
ACP)
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
Figure 2-3 - ACP Surface Control Panel
2.5 Where can an ART be run in the toolstring?
Conventional Wireline Operations: During Production Logging (PL)
or data acquisition operations, the ART is normally deployed at the
head of the toolstring, thereby effectively replacing the
conventional cable weak-point. All ART tools have a direct
through-wire linking the upper and lower head connections and in
non-operating mode the tool draws only a few micro-amps from the
line. It should be noted that in order for the ART tool to operate,
it generally requires direct wire connectivity to the cable head. A
maximum of up to seven ARTs can be positioned anywhere within the
logging toolstring; assuming that there is a direct connection to
the cable for each of them. This provides the field engineer with
the ability to release from a specific section of the string, for
example, below a nuclear fluid density tool.
Tractor Operations: During horizontal or highly deviated well
operations, ARTs are normally deployed above and below the downhole
tractor. As with conventional wireline operations, additional ARTs
can then be placed in the toolstring if required.
Perforating or Setting Tool Operations: In this scenario, it is
normal practice to position the ART above the correlating device,
that is, the gamma-ray (GR) tool, casing collar locator (CCL) or
GR/CCL combination. Guardian also recommends the use of a shock
absorber when running the ART with perforating guns. If required,
the ART can also be positioned below the correlation tool, however
this is dependent on whether the correlation tool circuitry
degrades the ART control signal such that the ACP cannot
communicate effectively with the ART. It would be therefore
necessary to perform a surface test in order to simulate the
system, with the ART positioned below the correlation device and
connected to the ACP using the correct length and type of wireline
cable to be used during the job.
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
2.6 What Guardian tools can I combine with an ART and in what
order?
The ART family of tools can be operated with the Gun Brake
System, Instrument Dynamics Controller, Powered Swivel Joint and
Voltage Protection Module (VPM-E and VPM-G). Tools which contain an
integral VSS (VPM ad GBS) must be deployed below the ART (and also
below any other non-VSS containing tools). If it is required to
deploy more than one tool containing a VSS within a toolstring,
then all VSSs except the lowest one should be bypassed. Different
VSSs / VPMs are available for different applications see section
2.18.
2.7 How do I run multiple ARTs in the same string?
In order to allow several ARTs to be run in the toolstring, each
ART has a user selectable address that is used to communicate and
identify itself to the ART Control Panel (ACP). The address is set
in the tool by means of an internal four-way DIP-switch. Therefore
when running multiple ARTs in a toolstring, it is important to set
the addresses before running in the well and care must be taken to
note the address and related position of each ART within the
toolstring, in order to prevent the release of the wrong ART!
All tools are supplied from manufacture and rental with a
default address set to one. If more than two tools are deployed in
a single tool string it is vital to ensure that none of the tools
is set to the same address.
2.8 What head types are available?
Guardian is able to provide a range of head types to suit the
field requirements of the ART, from standard designs to
client-specific heads. These include:
1. Standard Go A type mono pin. 2. Modified or reversed Go A
type mono pin. 3. Standard GO B (1 5/8 Acme) 4. BA-A3 (OTA). 5.
BA-A2 6. Schlumberger MH21/22. 7. Client Specified.
2.9 What ART equipment is required to perform a job?
Downhole 1. ART One or more (up to a maximum of seven) tools can
be combined and addressed in a toolstring. 2. Some form of VPM
(Voltage Protection Module) or VSS (Voltage Switching Sub) may be
required. 3. A Shock Absorber (such as the Guardian SAT) should be
run below the ART when perforating.
Surface 1. ACP ART Surface Control Panel 2. 110 volt or 240 volt
mains lead 3. Leads to connect ACP to wireline cable 4. Fishing
equipment:
i. 1 grapple for fishing ART-C ii. 1 3/16 grapple for fishing
ART-H/T/I
2.10 What does the ART look like electrically?
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
Electrically the ART is through-wired upper to lower head, with
a high-impedance Line Isolation Board connected to the
through-wire.
Figure 2-4 - ART/ACP Electronic Block Diagram
The ART/ACP system block diagram highlights the main functions
of the surface and downhole electronics. The surface ACP consists
of two boards which provide the power supply, processor and signal
control electronics. The downhole electronics of the ART also
consists of two boards, one providing the power supply, telemetry
and control circuitry and the second supplying the line isolation
circuitry. The Line Isolation Board (LIB) is used to disconnect the
internal electronics from the line unless the line voltage is
within pre-determined limits.
Figure 2-5 - ART Downhole Electronics
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
2.11 What track record does the ART have?
The first ART commercial operation was successfully carried out
in 1997, and as such, Guardians range of ART tools have many years
proven field experience in a variety of differing operations, from
tractoring through to perforating. ARTs have completed hundreds of
jobs on a global basis, and are currently operated by all of the
major oil service companies together with many regional and
independent service companies. During tractor operations in the
highly safety conscious sector of the North Sea, some operators and
service companies stipulate that a wireline operation will only
proceed if the ART and VPM safety devices are deployed in the
toolstring.
There are no known reports of any ART releasing prematurely or
not releasing when intended.
2.12 How many ARTs are in the field?
As of 2008, GGT has approximately 200 sets of ART equipment
operating in the field; this is a combination of purchased and
rental tools. This number increases annually by approximately
20.
2.13 With what tractors has the ART been run?
ARTs have been run with tractors from the following
companies:
AkerKvaerner (Maritime Well Service); Computalog/Precision
Drilling/Preussag; Welltec; Sondex; Smartract; Schlumberger.
2.14 Has an ART ever been released inadvertently or
accidentally?
GGT has never experienced an accidental or inadvertent release
of an ART during downhole operations.
2.15 Which service companies have run ARTs?
Amongst others, the following companies run ART tools:
Baker Atlas Computalog Expro Asmary Halliburton Maersk Maritime
Well Services (AKWS) Precision Drilling Preussag Read Well Services
Redneckz SmartTrac Sondex Schlumberger Weatherford Wellserve
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
Welltec.
Operating companies include:
BP Amoco Exxon Conoco Norsk Hydro Phillips Maersk PDO Oman Shell
SINOC COSOL Statoil Norway
2.16 Can the ART be used in wells containing H2S or CO2?
All ART tools are manufactured using NACE specification (MRO175)
materials for use in wells containing H2S/CO2. ART operations in
hostile environments and those containing high concentrations of
H2S or CO2 should be discussed on a well-by-well basis. Please
contact Guardians sales or technical support department for more
information.
2.17 What is the maximum perforating gun I can run with an
ART?
This is rather like the proverbial question How long is a piece
of string! It depends on many factors, including gun length,
diameter, charge loading, pressure, well deviation, toolstring
position and so on. For all gun-strings we recommend running a
shock-absorber such as a SAT (see section 7).
2.18 What happens if the shooting line shorts after perforating
can I still release if the gun string becomes stuck?
The ART operation is controlled from surface using the ART
control panel (ACP) providing a negative 82-volt supply to drive
the electronics and motor in the ART. Therefore in a basic
perforating string, with no selective perforating system, if the
shooting line shorts to ground after perforating with a negative
gun, the ART may not function correctly. This is because any motor
voltage or current sent from surface will be shorted to ground.
To overcome this and remove the potential problem of a shorted
perforating line, a number of solutions have been developed by
Guardian. These are known as VSSs (Voltage Sensing Switch) or VPMs
(Voltage Protection Modules). Generally, the difference is that a
VSS is designed to enable another piece of equipment (e.g., ART,
GBS) to operate under specific circumstances (eg. A shorted firing
line) whereas a VPM is designed to protect a piece of equipment
from voltages or currents within a toolstring; however, due to the
wide variety of applications of these products, this distinction
does not always hold true!
1. VPM-F - The VPM-F is run below the ART and completely blocks
the flow of negative current and voltage and so isolates the ART
control signal from any short below the ART and VPM sub. However,
in this arrangement, only positive polarity perforating can be
employed. The VPM-F can also be user-configured to block positive
voltages for other applications.
2. VPM-B The VPM-B is deployed when an ART is operated with the
DynaEnergetics RF Safe detonating system. The VPM-B passes the low
level signals through to the DynaEnergetics detonating switch, but
when subjected to a higher voltage, will cause the rupturing of a
fuse which disconnects the tools below. This enables the ART to be
powered by preventing the ART supply voltage being dissipated
through the DynaEnergetics system. Selective
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
perforating is available with this tool. Once the fuse has been
ruptured, it is not possible to reconnect the gun string without
coming out of the hole (see also VSS-H).
3. VSS-B - The VSS-B is designed to be deployed when selective
(+ve and ve) perforating is required using standard, resistorised
detonators. The VSS is run below the ART and uses various voltage
sensing elements and protection circuitry to allow the engineer to
shoot on both positive and negative polarity, whilst also acting as
a high impedance device when looking up from the top of the
perforating string. Therefore if a short appears in the gun below
the VSS, the ART will function normally as the VSS prevents the ART
from 'seeing' the short-circuit below it. When shooting using
positive polarity, only the forward bias of a diode (0.7 volts) has
to be broken down before the tool will pass current to the
detonator. However when shooting on negative polarity, additional
protection circuitry has to be broken down, requiring approximately
-130volts before the circuit will allow current to pass to the
detonator.
4. VSS-D - The VSS-D is designed to be used when selective
perforating is required using a voltage-sensitive RF Safe detonator
(e.g., HES RED detonating system). The VSS-D is similar to a VSS-B
but has a lower current-carrying capability and a lower voltage
leakage at temperature.
5. VSS-H - The VSS-H is deployed when an ART is operated with
the DynaEnergetics RF Safe detonating system. It operates in a
similar manner to the VPM-B, but contains a sophisticated switching
element rather than a fuse. This means that the VSS-H can be
deployed below a tractor/VPM-G to allow multiple Safe/Fire
switching cycles of the VPM and the firing of a ballistics device
between each VPM cycle.
6. VPM-G The VPM-G is designed as a safety device to be deployed
when running ballistics devices below a high voltage downhole
tractor. The device contains multiple switches, which, under
surface control, positively ground the gun firing line so that even
if the tractor malfunctions, the guns cannot be fired. Once the gun
is on depth, the VPM is operated to connect the firing line so that
the ballistics device can be triggered. The VPM-G contains an
integral VSS-B, D or H as required.
2.19 What procedures do I need to be aware of before initiating
an ART release?
Use of the ART to release a stuck toolstring should only be
contemplated once all normal tool retrieval techniques have been
exhausted. The logging engineer should follow Service Company
fishing protocols and discuss the various fishing options with the
company man and office based personnel wherever possible. There are
several conditions that might affect the decision to release the
ART, such as: -
Have the guns been fired? It is unlikely that an operator would
want to drop armed and loaded guns? What is the standard
operational procedure for the Service Company or Operator during
fishing operations?
Perhaps they insist on a cut and thread for all fishing
operations? Where in the well the string is stuck - open-hole,
across critical safety valves or the BOPs (rig or wireline)? Is
there a nuclear device, chemical cutter or any other hazardous
device tool below the ART? Is the correct fishing grapple and
associated equipment available to fish the toolstring?
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
Having established that the ART is to be released, follow the
manual guidelines on the ART operation, a brief description is
given in section 2.15 below. Once the ART motor has been activated,
indication that the tool has been released may be given in a number
of ways:
Current limit LED lights (when released, the tool is likely to
short circuit at the lower head); Current drops to zero; Current
meter shows a kick; Tension on surface kicks; Tools above the ART
can be retrieved from well;
In order to pull-off from the ART, it is necessary to exert a
minimum over-pull of approximately 100lbs at the ART to free the
upper section. This may translate to substantially more at surface
in a highly deviated and doglegged well due to cable drag along the
wells trajectory.
2.20 What fishing grapple do I require for the ART-C?
1 fishing head fitted to ART-C
Figure 2-6 - ART-C (1 OTIS) Fishing Head
ART-C Fishing Grapple P/N: 116-00272
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
2.21 What fishing grapple do I require for the ART-H/T?
1 3/16 fishing head fitted to ART-H/T/I
Figure 2-7 - ART-H 1 3/16 OTIS Fishing Head
ART-H Fishing Grapple P/N: 116-00084
Figure 2-8 - ART-H Fishing Head Assembly
ART-H Fishing Head Assembley P/N: 116-00086
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
What is the maximum ART load before, during and after
release?
Before Release: The maximum working load of the ART-C is 2
tonnes, whereas the ART-H/I/T is rated to 3 tonnes.
During Release: The recommended maximum load during the release
operation of the ART and the stuck toolstring is 400 lbs. The ART
will operate satisfactorily above this limit (up to the maximum
safe working load), however release at very high loads may result
in some damage to the fishing head/dogs.
After Release: Once the upper section of the ART has been
removed from the well, there are no specific restrictions on
fishing operations, except that the maximum fishing load should be
limited to no more than 10 tonnes. Once the upper section of the
ART is removed from the well, a standard 1 or 1 3/16 OTIS fishing
head remains; depending on ART type. Fishing operations can then
commence depending upon the service and oil companies fishing
protocol.
Figure 2-9 - ART-H Schematic - Before Release
Figure 2-10 - ART-H Schematic- After Release
2.22 How do I release an ART?
1. Disconnect all surface panels and power supplies from the
logging cable. Connect the ACP to the wireline cable at surface
using the BNC connector.
2. Set ACP selector switch to Safety position and switch on.
After about 5 to 7 seconds, the current meter should read 10 to
12mA.
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
3. Check indication on ACP front panel LEDs (current meter which
should read no more than 12mA plus any other current drawn by the
toolstring). These will initially scroll RED and after a short
delay, will indicate which ART(s) are connected and responding to
the panel by a continuous GREEN LED.
4. The cable can be slacked off completely, however there the
maximum tension at the tool head should not exceed 400 lbs.
5. Select which ART tool is to be released by means of the ACP
selector switch, 1 to 7.
6. The selected tool LED will flash GREEN for a short period
whilst it is being addressed and will then turn steady orange. At
this point the ARM button is enabled.
7. Press the GREEN ARM button on the ACP. After a short delay
the ARM LED will illuminate continuous RED indicating acceptance of
the arming command. At this stage it is possible to abort tool
release by switching the selector switch back to safety or
switching off the panel.
8. To release the tool press the RED RELEASE button. After a
short delay the corresponding tool LED and the MOTOR RUN will light
continuous red. A tool current between 40mA and 120mA indicates
operation of the release motor; this current is dependent on well
pressure and temperature. Indicators to suggest that the tool has
been released are given in section 2.12.
2.23 What happens if there is a cable insulation or continuity
problem can I still release?
A total failure of insulation anywhere in the wireline cable or
tool head will prevent operation of the ART. If the ACP panel is
connected and powered up, a cable problem may be indicated if none
of the LEDs is green with the switch in the Safety position, and
the line current is substantially more than 12mA (check display).
If cable insulation appears to have been lost, check line
resistance using both polarities of an ohmmeter. Powering up any
logging tools, correlation or downhole tractors in the toolstring
can also be used to confirm potential cable problems. Similarly, if
cable continuity is lost, the ACP will not be able to communicate
with the downhole ART and so a release will not be possible.
Figure 2-11 - Section of ART-H Fishing Head and Grapple
System
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
2.24 Can I reverse the ART motor and reset the ART after
release?
Having followed the correct sequence of events and activated the
ART release button, once the ART motor is running (and until the
tool actually releases) the release process may be aborted by
switching off the ACP. This will reset the downhole tool
electronics but it will not reverse the motor to put the release
mechanism back in its original position. Therefore once released,
the ART motor cannot be reversed under surface control in order to
reset the tool downhole. 2.25 Why cant I reverse the ART motor?
The motor used in the ART is bi-directional, requiring a
positive voltage to go clockwise and a negative voltage to turn
anti-clockwise. However, the downhole ART electronics and motor
control is designed to respond to a fixed set of negative pulses
and commands from the surface ACP and to only output a negative
voltage motor signal, so no matter what polarity signal is sent
from the surface, the motor will only rotate in one direction and
cannot be reversed. Therefore, in order to reverse the ART motor,
the ART has to be disassembled and the motor fly-leads disconnected
and attached to a positive voltage and current from an external
power supply.
2.26 Can I release an ART at surface?
Guardian strongly recommends not performing demonstration or
confidence boosting test releases of the ART-H or ART-C at surface.
The setup required is complex and it is far more likely that a tool
will not release successfully due to a problem with the setup than
with the tool itself. If the ART is run through its complete
release sequence on surface, which requires the tool to be
pressurised, as a confidence-boosting exercise then the tool will
have to be disassembled and rebuilt. This then leaves the question,
will the tool operate successfully having been rebuilt? The ARTs
have a 100% record since 1997 when deployed within their operating
envelope and for this reason we do not recommend surface release
testing of the ART.
Pre-job functional testing as described within the Operations
and Maintenance Manual confirms tool operation all the way through
to motor run. Over the years this has proved a highly effective
pre-job test. If a full release test is required however, it should
be performed in the following manner.
1. The entire operation needs to take place in a pressure vessel
capable of pressurising the tool to around 5000psi (all ARTs and
MRTs require well pressure to operate fully) and into which cable
connections can be introduced.
2. The pressure vessel requires a nitrogen accumulator to ensure
that pressure remains above 1000psi with a volume increase in the
pressurised fluid volume of 21cuin (350cc).
3. If the pressure vessel is vertical or sub-vertical it
requires sufficient length to be able to attach weight bars to
provide an axial load to the ARTs lower head of a minimum of
200lbs. (The tool may release with lesser weight but this is the
minimum guaranteed to release the tool).
4. If the pressure vessel is horizontal then a spring/piston
mechanism must be designed, built and attached the ARTs lower head
such that when the vessel is under pressure, the piston moves to
the bottom of the vessel, elongating the springs and putting a load
of at least 200lbs on the ARTs lower head.
5. Once the ART is installed into a suitable pressure vessel,
the operational release instructions from the manual should be
followed.
Following release, the Lower Feed-through Assembly in an
ART-H/T/F/J (p/n 303-00057) will be severed and will require
replacement.
2.27 Can I run and release the ART upside down?
The ART is supplied with either client specified upper and lower
connections or more typically with GO-A female upper head and GO A
male lower head. Due to this arrangement it is difficult, though
not impossible, to run the ART upside down depending on the pin and
head arrangement of the tools run above and below the ART. Due to
the direct feed-through wire design of the ART, it is however
possible to operate the ART upside down and to activate a release
using the surface control panel (ACP).
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Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
2.28 How often should I service the ART?
Correct guidelines for the full maintenance of the ART-C & H
are outlined in the respective maintenance and operations manual.
The preventative maintenance scheme suggested for use with all
Guardian equipment is divided into three phases.
Pre/Post-Job Maintenance
The pre/post-job maintenance covers tool operational checks,
wellsite calibrations, primary pressure seal maintenance and
general condition.
Routine Tool Maintenance (RTM)
Routine Tool Maintenance procedures are designed to be carried
out every 6 jobs or two months if the equipment has been used
infrequently. More frequent maintenance is recommended if the
equipment is used in hot or high pressure environments. This should
be scheduled according to maintenance policy. RTM is divided into
electrical and mechanical tasks - RTM(E) and RTM(M). It covers all
seal maintenance and the correct operation of sensors.
Tool Verification Check (TVC)
The Tool Verification Check is a set of in-depth tests and
measurements designed to ensure that the tool is operating
correctly within specification. The TVC should be carried out every
12 - 15 jobs or 6 months as appropriate. For more information on
the RTM and TVC maintenance, please refer to the respective
manual.
2.29 How much weight do I need below the ART to enable a
successful release?
To affect a successful release of an ART-H/J/F/T around 100 lbs
is required to pull off the top section of the ART from the fishing
assembly. It is therefore recommended to have at least 200 lbs of
weight beneath the toolstring when operating the ART, although
generally it will release with far less than this. In situations
where the toolstring is stuck, this is not an issue. However, when
the client wishes to intentionally drop an element or section of
the toolstring in a well, if the toolstring is not anchored in any
way (that is, it is not stuck) and is therefore floating, a
successful release cannot be guaranteed with less than 200 lbs. An
ART-C/G requires around 50-70lbs and an MRT up to 400lbs.
2.30 How long does it take to re-build an ART-C/H tool?
The time taken to rebuild an ART is dependent on experience and
prior knowledge of the ART mechanical assembly, with the ART-H/T
being more involved than the ART-C. A trained technician should
complete the operation within approximately 3 to 4 hours; however,
the first re-build for someone who is not familiar with the tool
may take up to 8 - 10 hours.
2.31 Do I need special training to service an ART?
No specific special training is required to service the ART.
Guardian provides complete and detailed manuals on the maintenance
and operation of the ART range of tools. These manuals include
complete instructions on how to disassemble and re-assemble the
tools, with detailed, exploded, 3D assembly diagrams, electronic
and mechanical drawings, spare parts lists and O ring lists.
However, we do offer and recommend a training course at Guardian or
on-site training at our clients location. Guardian cannot be held
responsible for tools that are incorrectly maintained or
serviced.
2.32 Is Guardian able to provide ART maintenance training?
Yes. Guardian will provide technician and engineer service
training. This can be run at Guardians facility in the UK or at the
clients office. Please contact our sales office on [email protected]
for a quotation.
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Safety By DesignSafety By DesignSafety By DesignSafety By
Design
Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
2.33 Does Guardian provide ART servicing and tool repair?
Yes. Guardian provides a full maintenance and tool repair
facility at its manufacturing and design base in the UK. On
reception of the tool, trained technicians will evaluate what work
is required, the cost of which is then quoted by the sales and
marketing group. Note that no work will be carried out on the tool
until the customer has been advised and agreed the costs. Guardian
has a policy statement in place to turnaround all repairs within a
10 working-day period.
2.34 What tools do I require to re-build an ART-H/T tool?
Complete sets of the few special service tools specific to each
type of ART, and Redress Kits comprising parts required for
servicing, are available from Guardian. The maintenance sections of
each manual detail other recommended hand tools.
2.35 What spares do I require to rebuild an ART tool?
Due to the robust design of the ARTs, minimal parts are required
to rebuild a tool after release. Spare part usage will therefore
depend on specific well conditions. The user should check the
condition of the feed-through wires, exposed O rings and the
condition of the fishing grapple after fishing. For complete
information on the operation and maintenance procedures for the ART
(see Question 2.28), please refer to the relevant ART manual
(Section 7). The manuals also contain full listings of Recommended
Spares.
2.36 What maintenance products are recommended for the re-build
of an ART tool?
The following table provides a list of products recommended for
use in servicing and maintaining the range of ART tools.
Product Part Number Size Application Lubriplate 930AA 302-00001
14oz Tin Lubrication of mechanical parts only or where lubricant
will not be in
close proximity to electronics boards or components. Should not
be used where gasses given off at temperature could come into
contact with electronics systems.
Lubriplate 930AA 302-00001 100ml Tube
Lubriplate 1444 302-00031 14oz Tube Lubrication of threads and
seals general application. Liquid O-ring 101 302-00030 1 lb. Tin
Lubrication of threads and seals general application (Preferred).
Silicone Grease 302-00002 100gr
Tube Pressure and fluid inlet ports where high retention under
temperature is required. e.g., PWH Pressure Inlet Port, ART
Pressure Balance Port. Do not use on threads. May be used on o-ring
seals.
Loctite 242 302-00004 10ml Tube
Used to lock fasteners (> M4 Thread) which may require future
release. Not recommended for use on any fastener < M4 thread. Do
not use on plastic components.
Loctite 601 302-00005 10ml Tube
Used to lock small metallic components permanently in place. Not
normally used during maintenance. Do not use on plastic
components.
DC200/50 302-00035 1 l. Tub Oil filling of pressure tool buffer
tubes and pressure balanced tools. e.g., PWH buffer tube.
Paratherm NF 302-00036 1 l. Tub Oil filling of pressure tool
buffer tubes and pressure balanced tools. e.g., PWH buffer tube.
(Preferred)
RTV 302-00016 100ml Tube
Used to secure massive components against vibration &
shock.
Loctite 638 302-00039 50ml As for Loctite 601 but where gaps
exist between parts. Sn96 303-00018 250gr Solder used for standard
temperature (350F/177C) boards. 24 SWG.
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Safety By DesignSafety By DesignSafety By DesignSafety By
Design
Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
Table 2-1 - Recommended Maintenance Products
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Safety By DesignSafety By DesignSafety By DesignSafety By
Design
Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
3 ART Specifications
Please see the applicable data sheets for product
specifications. These can be viewed and downloaded via our website
www.ggtg.net or by contacting [email protected].
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Safety By DesignSafety By DesignSafety By DesignSafety By
Design
Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
4 ART Applications and Release Case Studies
Client A:
An ART-H was deployed during a perforating operation (2 7/8 HSD
guns run on mono-cable) to a total depth of 18,600 feet and with a
max deviation of 65. Due to the depth and deviation of the well,
the service company was concerned that safety would be compromised
if the toolstring became stuck, as the engineer would have limited
ability to pull off the weak point as the maximum safe load on the
cable would be exceeded. This problem was compounded by the
deviation of the well and the ability of the winch-man to work down
enough cable tension to the head in order to be able to break the
weak point. The deployment of the ART therefore provided the
service company with the additional contingency and safe option of
pulling off from the gun-string using the electro-mechanical
release system in the event of a stuck tool.
Client B:
The oil operator requested the use of an ART during perforating
operations in under-balanced gas wells due to historical problems
of swelling and burst guns. Although specialist gas guns were
employed, the potential for gun swelling remained with the
possibility of the guns becoming stuck in the BOP stack or when
entering the wireline entry guide. The use of an ART-H therefore
allowed the operator the opportunity to drop the guns if they
became stuck after perforating.
Client C:
A European service company which routinely ran ARTs on downhole
tractor operations for other clients, made a presentation on the
benefits of running ARTs to the major middle eastern operator which
had just awarded it a new contract. At the time the operator was
not interested in running the ART but the service company policy
was to run them anyway. During a plug-setting operation in a
horizontal well, the tractor was run with ARTs above and below. The
shear stud failed to part and stuck the setting tool and tractor in
the well. Jars had been run below the tractor and were triggered
several hundred times without success over an eight hour period.
The service company then suggested activating the release tool,
although they were unsure if it would release having been subjected
to the severe jarring. The operator agreed and the release tool run
below the tractor was activated. The tractor was retrieved and the
setting tool abandoned, saving the operator either the cost of a
tractor or the cost of a fishing trip a minimum of $250,000. The
operator now insists on running ARTs with all tractor
operations.
Client D:
Running a plug and setting tool below a tractor into a
long-reach horizontal well on the Norwegian CS, the plug became
lodged just above setting height. A decision was taken to set the
plug at this depth and retrieve the setting string which contained
an ART above the tractor. The plug partially set and the setting
string could not be removed. Following substantial jarring, the
release tool was triggered and the cable and head retrieved from
the well. The tractor and setting tool were then fished on
drill-pipe. Releasing the ART significantly reduced the risk of
parting the cable at surface and an extended or impossible fishing
operation.
Client E:
An ART-C was deployed in a 1 11/16 production logging operation
due to the requirement of logging through a Y tool. Due to the
excess debris in the well during pumping and the potential for the
fullbore flowmeter to become clogged, the ART-C would allow the
engineer the ability to release from the stuck toolstring and pass
through the Y tool.
Client F:
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Safety By DesignSafety By DesignSafety By DesignSafety By
Design
Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
The ART-H has been deployed on numerous horizontal well tractor
operations in the North Sea. Due to the horizontal well operations,
the ability to be able to pull-off from the weak-point is severely
compromised. Applications for the ART-H have included perforating,
plug setting and production-logging operations. The addressable
nature and design of the ART-H enables the tool to be deployed
above and below the tractor. This allows the tractor to be
retrieved from a stuck toolstring, or in the situation where a
tractor becomes stuck, to allow the wireline and head to be
retrieved without having to try and break the weak point.
Client G:
An operator needed production logging and particular fluid
identification data from a well with increasing water cut. The
operator was very reluctant to run the operation due to known
tubing damage and debris in the well. The main concern was that the
fullbore flowmeter or centraliser would become stuck if debris
built up in the roller arms (spinner) or bowspring (centraliser)
and prevented them from closing properly, thereby increasing the
risk of a stuck toolstring. The service company suggested deploying
two 1 11/16 ART-Cs, one below the logging head, and a second below
the radioactive fluid density (Cesium 137) tool. An ART-C was
positioned below the nuclear tool in order to increase the chances
of retrieving the source if the tool stuck. The ARTs gave the
operator sufficient confidence to run the operation and the service
company generated over $35,000 total revenue. A specially modified
telemetry cartridge was used in this application to allow negative
voltage to be applied to the lower of the two ARTs.
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Safety By DesignSafety By DesignSafety By DesignSafety By
Design
Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
5 Voltage Protection Modules (VPM)
5.1 Why run a VPM in the toolstring?
Voltage Protection Modules (VPMs) are an essential safety tool
in the current wireline, tractoring or coiled tubing market, as
they provide protection against excessive line current or voltages
from damaging, destroying or detonating sensitive toolstring
components. VPMs are deployed to protect production-logging tools
or provide additional ballistic safety when running perforating or
setting tool operations on wireline.
In its simplest form, the VPM-A/B/F is designed to perform a
designated task depending on the type of operation and client
requirement. The VPM can therefore be configured to block or pass
current in either polarity (VPM-F) or alternatively limit the
voltage that the tool will pass to a set value, using various
voltage sensing elements (VPM-A/B). The VPM-F is used as an
additional safety device when running ARTs, as the tool can be
configured to block the negative (-) 82 volt control signal from
reaching the perforating guns or setting tool. The VPM-A/B can be
used in either conventional wireline operations or during tractor
jobs in order to limit the voltages reaching sensitive elements of
the toolstring.
With the increase in horizontal well drilling, the VPM has found
a particular niche in downhole tractors operations by blocking the
associated high voltage and currents from reaching production
logging, perforating or setting strings. To achieve this, the VPM-G
uses a surface control panel (VCP) and a set of downhole rotating
cam/switches to control the connection of the lower head of the VPM
to the toolstring above. It is therefore possible for the engineer
to initiate a surface controlled physical connect and disconnect of
the firing line whilst tractoring. VPMs therefore provide an
additional and completely independent protective safety system
during tractor operations. One of the key strengths of the VPM-G is
that whilst it operates in conjunction with the ballistics system
and tractor, its control system is independent of both.
The VPM (using the voltage sensing switch, see section 5.5) also
allows the continued operation of an ART if the perforating line
becomes shorted after perforating. The VPM acts as a high impedance
device when looking up from the top of the perforating string and
prevents the ART from 'seeing' any potential shorts in the firing
line below it. The VPM and ART range of safety products therefore
provide the ultimate in operational safety, by operating as
complimentary electrical and mechanical tools. In this context, the
VPM acts as an electrical safety device during perforating and
production logging operations, whereas the ART provides the
mechanical system enabling the controlled release of stuck downhole
tools.
5.2 For what applications would I use a VPM in my
toolstring?
Protection of logging tools from over-voltage; Isolation of
perforating or setting equipment from excessive line voltages;
Equipment protection during well-tractor operations; Additional
safety during standard wireline (or coiled-tubing) perforating
operations;
-
Safety By DesignSafety By DesignSafety By DesignSafety By
Design
Guardian Engineering Centre, Merlin House, Brunel Court,
Guardian Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Guardian
Engineering Centre, Merlin House, Brunel Court, Village Farm
Industrial Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial
Estate, Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate,
Pyle, Wales, CF33 6BL, UKVillage Farm Industrial Estate, Pyle,
Wales, CF33 6BL, UK
Tel:Tel:Tel:Tel: +44 1656 742100. Fax: +44 1656 742251. +44 1656
742100. Fax: +44 1656 742251. +44 1656 742100. Fax: +44 1656
742251. +44 1656 742100. Fax: +44 1656 742251. [email protected]
[email protected] [email protected]
[email protected] www.ggtg.net
Registered in the UK No. 6526912
5.3 Where do I position the VPM in the toolstring?
Operation VPM Tool Position
Wireline Data Acquisition VPM-A/B/G all run above logging or
data acquisition tools.
Coiled Tubing VPM-A/B/F/G all run above logging, perforating
guns or setting tools.
Tractor Operations VPM-A/B is run above the tractor. VPM-G must
be run below the tractor and ART, since the VPM-G is used to
disconnect the lower head (firing line) from the tractor.
Perforating operations All VPMs should be run above perforating
guns or setting tools. Note that Shock absorbers should be run as
standard between guns and VPM