Ch 02 Piping and Pipeline Maintenance

Ch 2 Piping & Pipeline Maintenance

2.1. Pipeline Components

Pig Straight

Bend/ Elbow

Block Valve

Flange

Kuliah MS4102 Perawatan Mesin 1

Pig launcher Pig

receiver

Straight pipe

Pig receiver

Tee




NPS & Schedule

Standard

Welded & Seamless Wrought Steel Pipe ASME B36.10M

St i l St l Pi ASME B36 19M


Stainless Steel Pipe ASME B36.19M

Specification for Line Pipe API SPEC 5L

Seamless carbon steel pipe for high temperature service ASTM A 106

Spiral welded steel or iron pipe ASTM A 211

Seamless austenitic steel pipe for high-temperature service ASTM A 376






Digunakan sebagai sambunganpada belokan pipa dengan radius kecil Short radius elbow adalah 1D

Elbow

kecil. Short radius elbow adalah 1D. Long radius elbow adalah 1,5D.

Pipe Bend


Digunakan sebagai sambunganpada belokan pipa dengan radius besar (Radius > 3D).

p


FITTINGS: Mitter Bend, Tee Joint



FITTINGS: Coupling, Cap, Plug



FITTINGS: Bushing, Cross, Reducer



FLANGE



FLANGE



FLANGE



VALVE: Rotary Motion

BALL VALVE CHECKVALVEBALL VALVE CHECKVALVE


BUTTERFLYVALVE

PLUG VALVE


VALVE: Sliding Motion

GATE VALVEGATE VALVE

NEEDLE VALVE


GLOBE VALVE


VALVE: Flexible Valve

DIAPHAGRM VALVE


PINCH VALVE


2.2. Maintenance Elements

Gas and liquid pipelines have similar maintenance objectives and programs:

“The primar p rposes of an pipeline maintenance program is“The primary purposes of any pipeline maintenance program, is to maximize throughput and prolong the life of a pipeline system while ensuring public safety and respecting the environment.”

Two types of maintenance activities:

1. Routine maintenance: planned activities and don’t involve an i id t


incident.2. Emergency activities usually result from incident: rupture,

leak pipeline segment or piping replacement.

There are also situations that overlap those of routine maintenance that can be lead to emergency maintenance.


Maintenance activities include the followings:

• Right-of-way (ROW) and facilities environment protection.• ROW and site maintenance• Pipeline depth of cover maintenancep p• Aerial inspection/patrol and leack detection• ROW erosion control and stabilization• Cathodic protection monitoring and maintenance• Pipeline integrity assessment (corrosion and structural)• Pipeline repair and modifications• Pipeline encroachment assessment


• Pipeline encroachment assessment• Facilities identification, signs and markers• Aesthetics and landscaping• Equipment (i.e. valves, metering) operational test and

routine maintenance.


Maintenance activities that are not routine in nature, but are performed as a consequence of undertaking the routine maintenance, include:

• Trenching and excavationTrenching and excavation

• Locating pipelines

• Pipeline realignment/relocation

• Foreign crossing

• Hot tapping and stub installation

• Pigging


gg g

• Welding, including Welders qualification

Maintenance and repair welding

Cutting


Maintenance activities that are not routine in nature, but are performed as a consequence of undertaking the routine maintenance, include:

• Safety management, including:Safety management, including: Indent Safe working practices Safety gearing Safe work permit Confined space entry Fire protection Material amd hazardous material handing and disposal


Material amd hazardous material handing and disposal Personal protective gearing Incidence recording and reporting

• Record keeping

• Training


2.3. Pipeline Maintenance Code Requirment

Standards Pipeline regulations (EUB, 2003) or acts and codes will

i th t t i t i th i i li di trequire the operators to maintain their pipeline according to prescribed standards. For example: routine maintenance includes inspection of all pipeline ROWs at least once annually.

These inspections are recommended in order to reduce potential third-party interference on such pipeline.

G d l i i ti l t ll i li i t


Good planning is essenstial to all pipeline maintenance and repair work work is done safely, on schedule and with minimum environment impact.

Scheduling and preparation are important for timely maintenance and safe work operation.


Scheduling and preparation cover the following:• Maintenance schedule preparation• Availability of tool and equipment in good and safe

working condition• Avalability of necessary resources for the job• Previous on-the-job training of personnel to ensure

work safety and efficiency• Availability of safety and fire-fighting equipment, all in

good working condition.• Necessary environmental protection measures


y p• Permit to work.


FrequencyTable 2-1 provides a summary of routine maintenance activities that are required to be performed on a pipeline as per code requirements.

TABLE 2 1 R ti M i t S h d l f M j Pi li El t

MaintenanceActivity

MaintenanceSchedule/Frequency

Requirement/Remarks

ROW inspection Annual

CSA Z662 : (2003) Sour gas (> 10 MolesH2S/k-mole NG) required monthly/bimonthly

HVP/sour condensate: bimonthly/weeklydepending on class location

TABLE 2-1 Routine Maintenance Schedule of Major Pipeline Elements


p g

Pipeline patrol/leak detection/corrosion (gas)

Monthly (gas) Industry norm, B31 requires periodic/as required---leak and corrosion survey report kept while line in service

Biweekly (liquids) :LPG/NH3 lines<1 week in common areas

ASME B31.4 (1998)


MaintenanceActivity


Requirement/Remarks

Class 1,2 : Annual

TABLE 2-1 Routine Maintenance Schedule of Major Pipeline Elements (cont’d)

Pipeline patrol(gas lines)

ASME B31.8 (1999)Class 3: 6 months

Class 4:3 months

CP monitoringAnnual, not to exceed 15 months

ASME B31.1 (1999)

CP : Pipe to soil potential and

Monthly, Soil survey once per year

Industry norm


rectifier readingsper year

Internal corrosion monitoring

< 6 monthsASME B31.4 (1998): if line internally coated, pigged, dehydrated/corrosion inhibition, corrosion coupon used

Exposed pipe: External monitoring;

< 3 years ASME B31.4 (1998)


MaintenanceActivity


Requirement/Remarks

EncroachmentP i di l

TABLE 2-1 Routine Maintenance Schedule of Major Pipeline Elements (cont’d)

c oac e tassessment

Periodic or annual

Class location assessment (Gas line)

Annual ASME B 31.8 (1999)

Valve inspection/operation

AnnualASME B31.4 and B31.8, partial operation required

Valve testing Annual


g

Remote control shutdown devices

Annual B 31 : For functionally test

Relief valves (liquid) < 5 YearsASME B31.4 (1999): LPG/CO2/NH3 Line/Storage


2.4. ROW and Site Maintenance

Definition:

A strip of land usually about 10 t 50 id ( fi )10 to 50 m wide (see figure), containing the pipeline and usual appurtenances (Pipeline 101, 2002).

The ROW:


• Enables personnel to gain access for inspection, maintenance, testing or emergencies.

• Maintain an unobstructed view for frequent aerial surveillence• Identifies an area that restricts certain activities to protect the

landowner and pipeline itself.


Reason for ROW Maintenance

• Maintaining the integrity of the ROW is a critical component of the ongoing O&M.

• On going inspection and servicing the ROW are essential processes that focus on protecting the integrity of pipelineprocesses that focus on protecting the integrity of pipeline, environment and public safety.

• Help ensure the continued safe, efficient operation of the pipeline and security of the supply for pipeline customers.

ROW Maintenance Requirements


ROW Maintenance Requirements

Three main areas of concern in ROW maintenance.• Vegetation management • Erosion and soil stability (settlement/heave, etc.)• Landowner concerns


Environmental Protection

The objectives are:

• Ensure compliance with landowners and all regulatory requirements

• Ensure compliance with the owners’ approved environmental plans, procedures, drawings and standards.

• Ensure the lands to their original condition soon after completion of construction

• Identification of environmental issues affecting pipeline operation as well as impact on adjacent land


operation as well as impact on adjacent land

• Measure actual major environmenta; effects such as slope movement, settlement/heaving to confirm any impact on design and operation.


Environmental Protection (cont’d)

Post-construction monitoring will generally focus on the following:

• Reclamation

• Re-vegetationg

• Erosion control drainage systems

• ROW and slope stability

• Stream (small river) crossings

• Wildlife impact assessment

• Heritage resources


• Impact on evnvironmentally sensitive areas such as water supply reservoirs.


Signs and Markers

Pipeline and facilities are marked (see figure) in accordance with the requirements of the original design as accurate as possible –and as close to their location– to reduce the possibility of damage or interference resulting from third partypossibility of damage or interference resulting from third-party activity.

They also assist in the performance of survey and patrolling requirement.

To maintain a pipeline ROW, pipeline companies usually mark the ROW and the site boundaries with either or all or the following:


following:• Markers post/pole/fences• Pipeline warning signs• Aerial markers• Owner facilities’ directional sign• Owner facilities sign




Surveillance Program

A continuing surveillance program is usually conducted to monitor for unusual operating and maintenance conditions.The surveillance programs cover the following:

a Patrols at regular intervala. Patrols at regular intervalUnsafe conditions along the pipeline ROW may consist of:• Exposed or damaged pipe• Leaks• Pipeline breaks• Construction activity• Soil erosion and vegetative cover• Shallow pipe


Shallow pipe• Encroachment• Atmospheric corrosion• Poor condition of pipeline signs and markers• Missing pipeline signs and markers• Dead, damaged or altered vegetations


Surveillance Program (cont’d)

b. Gas/liquid leakage detection surveysc. Valve inspectionsd. Pressure regulating, relieving and limiting inspectionse Failure investigationse. Failure investigationsf. Corrosion controlg. Pipe inspections



Site Maintenance Requirement

Facilities sites, such as metering or valve, are generally graded and in most instances graveled. Chain link security fencing is install around most facilities.



Maintenance of site may include removal of grss and shrubs, trees, etc. and snow removal is undertaken from some access roads and facilities where frequent access is required during the winter month.

Access roads: Inspection roads need to be maintained to pensure redy and available access for maintennce.

Depth of cover is expected to be maintained over the lifetime of the pipeline (regularity complaince: EUB, 2003 & ASME code).

Pipeline excavation: A pipeline may be excavated to check for corrosion, to cross one pipeline with another, to make


ddition to a pipeline system or to make repairs. Consult the safe and efficient procedure of excavation.


Pipeline Patrol (cont’d)

A detailed list of what is noted while air-patrolling the pipeline ROW is provided in Table 2-2.

Patrol by helicopter or fixed-wing aircraft is normlly conducted on monthly basison monthly basis.

In emergency situations, winter and spring runoff condition, a helicopter provides a rapid response for a detailed check.

During the air patrol, obseevation generally includes review on the condition of:• Hills/mountain• River crossing


• Shifts in soil stabilization• Signs of erosion• Valve sites, meter stations• Pump/compressor site.

Other methods for pipeline ROW monitoring are walking, driving all terrain vehicles and satellite imagery.


Geotechnical Problems Signs of foreign activity• Soil erosion • Third-party damage

• Sand blowouts • Drainage

• Cave-ins/subsidence • Digging

TABLE 2-2 Details of Air Patrol Observation

• Hill Slides or hill sloughing • Irrigation

• Sink holes/settlements • Seismic activity

• River diversion/scouring • Dug-outs

• Canal seepage/drainage • Farmers’ deep tillage

• Fallen tress, which might indicate a new slide or the beginning of a new slide

• Survey flags/stakes• New power lines and cables

• Floating swamp weights • New subdivisions/buildings

• Exposed pipe/loss of cover• Seismic activity/soil slides

• Local forest and timber activities (e.g., skidders crossingthe line, sspecially in muskeg or wet areas)


• Presence of heavy equipment

Evidence of leaks• Soil discoloration Any maintenance to be done on the R.O.W

• Water bubbling

• Dead vegetation

• Isolated Patch of Wet Ground


2.5. Pipeline Pigging

Main purpose:• Cleaning & inspecting

Other purpose:Other purpose:• Hydrastatic testing

• Air/nitrogen removal

• Petroleum product batch separation

• Pipeline commissioning

• Pre-inpsection and certification of


newly built pipelines

• Integrity assessment

• Decommissioning of an environmentally unsafe pipeline to inert condition.






Type of Pigs:



Utility pigs: Used to clean the pipe, seperate contents and dewater the line. This includes:

• Cleaning pigs: Purpose is to remove solids and debris that ccumulated on the pipe walls over time.

• Sealing pigs: Purspose is to perform hydrostatic testingSealing pigs: Purspose is to perform hydrostatic testing, dewatering and removal of condensat.Typical pigs of this type are referred to as sphere, solid cas and mandrel pigs.


Cleaning pig in a pipeline


Mandrel Pig


Brush PigScraper Pig


Spherical Pigs


Components of an HAPPhydraulically activated power pig


In-line inspection (ILI) tools includes: • ILI or smart pigs: Main purpose is to determine metal-loss

and corrosion; they provide pipe geometry, temperature, photographic inspection, crack and leak detection, and mappingmapping.

When in operation, ILI pig can: Be located in pipeline via GPS or simple transmitters Perform function using ultrasound and specialized computer

software.


Typical ILI or smart pigs


• Geometry pigs/tools include:• Caliper pig• x, y, z geometry (inertial guidance) tool• Metal loss ILI tools• Conventional magnetic flux

Hi h l ti ti fl l k (MFL)• High-resolution magnetic flux leakage (MFL)• Transverse field inspection (TFI)• Ultrasonic


Caliper Pig MFL


Gel pigs: Made of static gelled liquids. Some gels are made from various chemicals. Their typical uses are product separation, removal of stuck pigs, line filing and hydro testing.

There four types:There four types: Dehydrating gel Hydrocanbon gel Debris pick-up gel Batching or separator gel.



2.6. Pipeline Repair

Integrity Assessment:

The failures are causes by various mechanismes such as• Corrosion (external & internal)( )• Stress corrosion cracking (SCC)• Third-party damage/contacts• Soil movement/instability• Material defect• Construction practice• Operating problems.

The consequences may be group two categories:


The consequences may be group two categories:• Business consequences: loss of revenue, products,

organization reputation and prestige• Safety consequences: fatalities, injuries, pollution, explotion,

fire, property damage, environmental impact, etc.


Public concern for safety and environmental impact are the basis for the industry to initiate and implement an integrity managemenet programs.

Pipeline integrity inspection is the basis for collecting integrity data thro gh a risk assessment techniq e hile prioriti ing anddata through a risk assessment technique, while prioritizing and determining the appropriate repair techniques RBI.

Pipeline integrity inspection has developed from a mere gauging of the internal size of a pipeline (hence, pipeline inspection gauge, PIG) to usage of modern development of high-resolution tools. This includes:• Magnetic flux leakage (MFL)


• Magnetic flux leakage (MFL)• Inertial (x, y, z geometry)• Ultrasonic• Crack detection tools• Etc.


Inspection Technologies:

There are several techniques available to assess the integrity of pipelines as follows:

• Visual inspection• Depth of cover survey• Depth of cover survey• External NDT

Radiography Magnetic particle testing Dye penetrant Ultrasonic inspection

• Cathodic protection monitoring


• Coating disbondment and damage survey• Hydrostatic testing• Use of geometry ILI tools

Caliper pig x, y, z geometry (inertial guidance) tool


Inspection Technologies (cont’d):

• Use of metal loss ILI tools Conventional magnetic flux High-resolution magnetic flux leakage (MFL) Transverse field inspection (TFI)Transverse field inspection (TFI) Ultrasonic

• Use of stress corrosion cracking (SCC) tool

ILI and SCC tools are mostly used as inspection for various tasks, including the following, (Uzelac, 2000):

Metal loss Wall thickness measurement


Cracking Geometry measurement Bend measurement Curvature monitoring Pipe movements and profiling


Defect Assessment:

It is the operator’s and the industry’s standard that dictates which defects need to be repaired and to what extent. Such defects are summarized below (Hewing, 1999)

• Corrosion• Corrosion• General: Pitting, Erosion• Gouge (possibly caused by mechanically induced damage)• Mechanical damage (dent with a gouge)• Dents: Smooth (localized distortio), Kinked (rapid change of

contour)• Cracks (planar two-dimensional defects with fracture)


• Cracks (planar two-dimensional defects with fracture)• Laps/livers/lamination (manufacturing defects)• Spalling (severe abrasion)/arc strikes.• SCC (stress corrosion cracking)• Perforations (causing rupture/leaks)


Repair and Rehabilitation

Repair techniques include the following:• Temporary/leaks clamps• Grinding/dressing

W ld d iti• Weld deposition• Patch repair• Snug-fit sleeves/PetroSleeve®

• Stand off sleeves• Hot-tapping • Stopple and bypass


• Epoxy sleeve repairs• Clock spring repairs• Other composite repairs

The application of the above repair technques are summarized in Table 2-3.


Type Superficial Moderate Severe Extreme

TABLE 2-3 Summary of Repair Applications

Grinding/dressing X X

Weld deposition X X

Full ercirclement X X

Hot tap X X


Hot tap X X

Cutout X


Temporary Clamp

Patch repair


Hot tap Bend epoxy repais sleeves


Repair and Rehabilitation

Repair techniques include the following:• Temporary/leaks clamps• Grinding/dressing

W ld d iti• Weld deposition• Patch repair• Snug-fit sleeves/PetroSleeve®

• Stand off sleeves• Hot-tapping • Stopple and bypass


• Epoxy sleeve repairs• Clock spring repairs• Other composite repairs

The application of the above repair technques are summarized in Table 2-3.


Integrity Management Programs

Managing pipeline system integrity in a proactice manner is essential for all owners and operators of hazardous liquid or natural gas pipelines.

In the late 1990s and to date the United State Department of In the late 1990s and to date, the United State Department of Transportation (DOT) has taken initiative to ensure that U.S. Liquid pipeline companies have integrity management programs in place that define processes that a company utilizes for the purpose of improving pipeline safety and striving for incident-free operation.

API Standard 1160 Managing System Integrity for Hazardous


API Standard 1160, Managing System Integrity for Hazardous Liquid Pipelines, First Edition, November 2001, was developed to assiste operators to comply with newly established federal rules in US regarding pipeline integrity management in high-consequence areas (HCAs) (Jaske, 2002).


The guiding principles used to establidh API 1160 can be applicable to all pipeline systems and are as follows:

• Integrity is built in from the beginning• Use traned people and defined processes to operate

maintained facilitiesmaintained facilities.• IM programs must be flexible• Integrate information• Risk assessment is key and continuous• Understand and utilize new technology• Third-party evaulation of IM systems.



An IM program, as defined by U.S. DOT, is a documented set of policies, processes and procedures that includes, at a minimum, addressing the following elements:

• A process for determining which pipeline segments could affetc an HCAaffetc an HCA

• A Baseline Assessmnt Plan• A process for continual integrity assessment and evaluation• An analytical process that integrates all availablr information

about pipeline integrity assessment method and data analysis• A process to identify and evaluate preventive and mitigative

measures to protect HCAs


measures to protect HCAs• Method to measure the integrity management program’s

effectiveness• A process for review of integrity assessment result and dat

analysis by qualified individual.


The key to any IM Programs is to establish a Baseline Assessment Plan with the following elements addressed:

• Identify all pipeline segments that could affect HCAs• Specify the integrity assessment method(s) for these segments

(acceptable methods include internal inspection hydrostatic(acceptable methods include internal inspection, hydrostatic pressure testing or equivalent methodology)

• Prioritize, based on risk assessment• Provide a schedule for assessment• Explain the technical basis for integrity assessment method(s)

selection and risk factors used in scheduling the assessments.



References

Mo Mphitpour, Jason Szabo and Thomas Van Hardeveld, “Pipeline Operation & Maintenance: A Practical Approach”,

kASME, New York, 2005.


Ch 02 Piping and Pipeline Maintenance

Documents

piping pipeline maintenance2

pipeline system

mkuliah ms4102 perawatan

piping replacement

structural pipeline

leak pipeline segment

emergency maintenance

routine maintenance