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GMR Bajoli Holi Hydro Electric Project (180MW)Techno-Commercial Bid Document
ICB No. - GBHHPL/ICB-002/LOT 3
3 x 60 MW BAJOLI HOLI HE Project
Technical DescriptionFrancis Turbine
2TFV00-0000-00718586
Revision -
Technical DescriptionFrancis Turbine
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Technical DescriptionFrancis Turbine
2TFV00-0000-00718586
Revision -
TABLEOF CONTENTS
1 Scope of Supply...................................................................................................................................... 4
1.1 Supply limits with civil work.................................................................................................................... 4
2 General Information............................................................................................................................... 5
2.1 Design Parameters................................................................................................................................ 5
2.1.1 Main Data........................................................................................................................................... 5
2.1.2 Operating Conditions.......................................................................................................................... 52.1.3 Output and Efficiency.......................................................................................................................... 5
2.1.4 Hydraulic Engineering Codes:............................................................................................................5
2.2 Design and Construction Requirements................................................................................................5
2.2.1 General............................................................................................................................................... 5
2.2.2 Applicable Standards and Codes........................................................................................................6
2.2.3 Allowable Stresses and Load Cases...................................................................................................7
2.2.4 Surface Finish..................................................................................................................................... 7
2.2.5 Painting and Surface Treatment.........................................................................................................8
3 Equipment Description........................................................................................................................... 8
3.1 Runner................................................................................................................................................... 8
3.2 Shafts.................................................................................................................................................... 9
3.2.1 Turbine Shaft...................................................................................................................................... 9
3.2.2 Couplings............................................................................................................................................ 9
3.3 Inlet Parts............................................................................................................................................... 9
3.3.1 Spiral Case with inlet pipe.................................................................................................................10
3.3.2 Stay Ring and Support Ring..............................................................................................................11
3.3.3 Pit Liner............................................................................................................................................. 11
3.4 Distributor............................................................................................................................................. 11
3.4.1 Wicket Gate with Bearing..................................................................................................................12
3.4.2 Wicket Gate Mechanism with Operating Ring................................................................................... 12
3.4.3 Servomotor....................................................................................................................................... 14
3.4.4 Head Cover....................................................................................................................................... 14
3.5 Bottom Ring ........................................................................................................................................ 153.6 Shaft Seal............................................................................................................................................ 16
3.6.1 Operating Seal (hydrostatic).............................................................................................................17
3.6.2 Standstill Seal................................................................................................................................... 18
3.7 Draft Tube............................................................................................................................................ 18
3.8 Bearing................................................................................................................................................ 19
3.8.1 Guide bearing................................................................................................................................... 19
3.9 Accessories.......................................................................................................................................... 20
3.10 Installation Device.............................................................................................................................. 20
4 Materials................................................................................................................................................ 20
5 Spare Parts............................................................................................................................................ 21
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GMR Bajoli Holi Hydro Electric Project (180MW)Techno-Commercial Bid Document
ICB No. - GBHHPL/ICB-002/LOT 3
3 x 60 MW BAJOLI HOLI HE Project
Technical DescriptionFrancis Turbine
2TFV00-0000-00718586
Revision -
6 Instruments and Control Equipment...................................................................................................21
7 Transportation, Erection and Commissioning...................................................................................21
8 Tests....................................................................................................................................................... 22
8.1 Shop Assembly and Tests....................................................................................................................22
8.2 Field Tests............................................................................................................................................ 22
8.3 Field Efficiency Tests........................................................................................................................... 23
9 Training.................................................................................................................................................. 23
10 Operation and Maintenance............................................................................................................... 23
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ICB No. - GBHHPL/ICB-002/LOT 3
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Technical DescriptionFrancis Turbine
2TFV00-0000-00718586
Revision -
1 Scope of Supply
This proposal document provides an overview to the works and services performed by Voith
Hydro. Particular emphasis is given to those aspects of the product scope which demonstrate
the superiority of many of the special features incorporated into todays design.
The turbines will be complete with spiral case, stay ring, pit liner, head cover, Guide Vanes with
operating mechanism, bottom ring, draft tube, runner, shaft, shaft seal, guide bearing, andaccessories.
Supports, stiffeners and other packing material necessary for transportation and erection are
included.
Special tools and devices required for installation, disassembly and maintenance of the
equipment will be supplied as well as piping, instrumentation, cabling and wiring.
The scope comprises design, manufacture, shop testing, transportation, erection at site, site
testing, commissioning and reliability run of the unit.
The documentation of supplied equipment contains assembly drawings, calculations, as-built
drawings and operation & maintenance manuals.
1.1 Supply limits with civil work
Aligning, fixing and bracing of turbine structures and parts which will be embedded and/or
grouted in the secondary, and the following concrete stages, is included in the turbine scope of
supply.
Concrete and grouting material for embedment of all components, i.e. supply, placement,
monitoring and verification of the concreting process is responsibility of the civil works
contractor.
Piping to be embedded in the concrete for pressure measurement and Winter-Kennedy-
connections are included.
Intake and draft tube embedded drainage pipes and all associated valves, the installation
and pressure testing before embedment, are included.
Gratings to cover floor trenches will be provided and installed by the civil works contractor.
The supports for the piping to be laid in the trenches are included.
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GMR Bajoli Holi Hydro Electric Project (180MW)Techno-Commercial Bid Document
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Technical DescriptionFrancis Turbine
2TFV00-0000-00718586
Revision -
2 General Information
2.1 Design Parameters
2.1.1 Main Data
For main data see Guaranteed Technical Particulars.
2.1.2 Operating Conditions
For operating conditions data see Guaranteed Technical Particulars.
2.1.3 Output and Efficiency
For turbine output and efficiency data see Guaranteed Technical Particulars.
2.1.4 Hydraulic Engineering Codes:
International Code for Hydraulic Turbines, Storage Pumps and Pump-Turbines - Model
Acceptance Test, IEC Publication 60193 (1999)
Field acceptance tests to determine the hydraulic performance of hydraulic turbines,
storage pumps and pump-turbines; IEC Publication 60041 (1991)
Cavitation Pitting Evaluation in Hydraulic Turbines, Storage Pumps and Pump-Turbines;
IEC Publication 609 (1977)
2.2 Design and Construction Requirements
2.2.1 General
The turbines will be of the Francis type with vertical shaft arrangement. The turbine is designedto run safe and stable considering multiple daily start-stop-cycles.
The turbines are rotating counter clockwise when seeing from above. The turbine shaft is
directly coupled to the generator shaft.
The power unit will be equipped with three guide bearings, one close to the runner on the head
cover, other below the generator and third on top of the generator.
The thrust bearing, for carrying the weight of the rotating parts of the turbine and the generator
as well as the hydraulic thrust, will be furnished as part of the generator.
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The uniform water inlet to guide apparatus is performed by a full spiral case with stay ring and
stay vanes. The water discharge from runner to tail race is done by an elbow-type draft tube
with steel lining up to the length of 5 m from runner center line. Thereafter, its shape will be
formed in the concrete as per the suppliers drawing.
The flow is regulated by Guide Vanes operated by two servomotors supported on the civil
structure of the turbine pit. Reliable operation including Safe closing of the Guide Vanes shall be
achieved by a nitrogen/oil pressure accumulator.
The turbine will be designed and constructed to provide clearances for axial movement of its
rotating parts as required by the generator design for inspection, adjustment and dismantling of
the thrust bearing.
The maximum turbine internal pressure resulting from pressure surge and water hammer for
emergency closing of the units against the maximum flow at maximum head water level will be
calculated. The design pressure for spiral case, stay ring, head cover, distributor and other
pressure parts will be equal to the calculated maximum internal pressure.
For the arrangement of the turbine please refer to the power house layout drawings
For further technical data refer to Guaranteed Technical Particulars.
Design modifications(if any) and improvements/optimization wherever required shall be
discussed and carried out during detail engineering of machines by Voith after necessary
approval from customer.
2.2.2 Applicable Standards and Codes
The standards, codes and manuals cited throughout this technical description are used to
establish the level of safety, precision, quality, class of materials, acceptability, tolerances etc.,
to which the work is to be performed. Where these are cited, the latest revision or edition will
prevail. Other standards, codes and manuals that will provide an equivalent level of safety,
precision, quality, class of materials, acceptability, tolerances, etc. may be substituted.
Specific standards, codes and manuals are referred in the appropriate parts of this specification
documents. Following is a list of references to sources for some general codes and manuals
cited in the specification documents.
IEC and ISO are the leading Standards.
ANSI - American National Standard Institute
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ASTM - American Society for Testing and Materials
ASME - American Society of Mechanical Engineers
AWS - American Welding Society
AISC - American Institute of Steel Construction
ISA - Instrument Society of America
VDE - Verband Deutscher Elektrotechniker
DIN - Deutsche Institut fr Normung
IS - Indian Standards
ISO - International Standardization Organization IEC - International Electro-technical Comission
NEMA - National Electrical Manufacturers Association
IEEE - The Institute of Electrical and Electronic Engineers, Inc.
In addition to the application of many international accepted standards Voith turbines are
subject to several internal standards, which are more detailed and more specific for hydraulic
machines than contemptible general standards.
2.2.3 Allowable Stresses and Load Cases
The turbines will be able to withstand all stresses arising in continuous operation or occurringoccasionally without being endangered or damaged.
The turbine components will be sized in accordance with the proven internal Turbine Design
Guidelines, on which our component design and dimensioning is based. This internal standard
defines precisely the allowable stresses for different load cases and takes into consideration the
availability of finite element calculations.
The Voith Hydro standard for allowable stresses and the definition of the loading cases are
summarized in document Turbine Design Guidelines / Allowable Stress Levels.
2.2.4 Surface Finish
All surfaces of the turbine water passage area will provide a smooth-contoured hydraulic
surface.
The surface finish roughness will be indicated on the component drawings and Voith standards
will be at least in accordance with ISO 4287, Roughness comparison specimens.
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Revision -
2.2.5 Painting and Surface Treatment
All equipment furnished and installed will be completely painted for final use, with the exception
of those parts or surfaces that are specifically designated as unpainted.
Surfaces to be painted will receive the preparatory treatment and coating according to Voith
Hydro Technical Group - GA General Application for Paints, Coatings and related materials in
Hydro Power Plants. (Attached along with offer)
All paint materials, supplies and articles furnished will be standard products of recognized
reputed manufacturers.
The paint used for touch-up in the field will be of the same quality and colour as used in shop
painting. The touch-up painting will be done with material corresponding to each coat shown in
the painting schedule.
3 Equipment Description
3.1 Runner
The runner will be a weld fabrication of high strength stainless steel composed of 13%
chromium and 4% nickel and will consist of the crown, the blades, the band, the runner cone
and the labyrinth rings. The runner cone will be an integral part with the runner crown. The
rotating labyrinth rings will be integral parts of the runner when supplied.
Numerically controlled machining of runner entrance and discharge creates perfect hydraulic
passage. Runner inspection and quality control regarding hydraulic surface are according to
IEC 60193. The surface finish of the hydraulic passages will be ground smooth to minimize the
hydraulic friction losses.
The runner will be designed to allow axial movement.
The runner will have a bolted flange connection for attaching to the shaft.
The runner will be statically balanced according to ISO1940-1 class G6, 3. The finished runner
is supplied in one piece from the manufacturing works.
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Technical DescriptionFrancis Turbine
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Revision -
Fig.1- Typical 3D view of Runner
3.2 Shafts
3.2.1 Turbine Shaft
The shaft will be of forged steel and will be provided with flanges on both ends suitable for the
attachment with the generator shaft at one end and turbine runner at the other end.
The turbine shaft will be designed to operate safely without excessive vibration and at maximum
torque without exceeding the allowable stresses.
3.2.2 Couplings
The coupling between runner, turbine shaft and generator will be preferably of friction type with
pre-stressed bolts which is inline with specification requirement. However, based on detailed
calculations of transmittable friction torque, final decision regarding type of coupling shall be
discussed and agreed during detailed engineering. Based on final coupling type, shaft
alignment shall be decided and also discussed during detailed engineering.
3.3 Inlet Parts
The complete spiral comprises the inlet pipe, the spiral case and the stay ring.
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3 x 60 MW BAJOLI HOLI HE Project
Technical DescriptionFrancis Turbine
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Revision -
Although the spiral will be embedded in concrete, it will be designed to withstand, without any
support from concrete, the internal design pressure, given by the water hammer calculation. The
design stresses for this condition will not exceed the maximum allowable stresses.
The spiral case together with the inlet pipe and the stay ring will be pressure tested at site prior
to concrete embedment. Bulkhead for inlet pipe and stay ring will be supplied.
Embedment will be done with partial internal pressure (approx. 50 % of Minimum static head).
The spiral case will be dewatered by a piping system leading from the inlet pipe to the draft
tube. The piping will be opened and closed by a manual operated valve.
3.3.1 Spiral Case with inlet pipe
The spiral case will be factory welded to the stay ring assembly as far as practicable and
suitable for transportation.
The spiral case will be made as a welded steel plate construction. The spiral case will be
designed for fabrication in radial sections. Field joints will be kept to a necessary minimum in
order to allow transportation of the maximum possible assembly. The use of longitudinal jointsbetween spiral case plates will be avoided as far as practicable. Where longitudinal joints are
necessary, their location will be carefully selected to facilitate welding and weld examination.
The connection joint between the spiral case and the inlet pipe will be field welded. Sufficient
adjustment allowance will be provided to align the segments before field welding.
All necessary stiffener rings, pads or brackets and connections for the application of jacks and
tie rods during field erection will be supplied. These appendices will be designed to support and
position the spiral case during all conditions of installation and concreting. The spiral case will
rest on solid foundation and bracing during embedment.
Onewatertight man door will be located for convenient access to the interior of the spiral case.
The inner surface of the man door will conform to the contour of the spiral case interior.
Four pressure taps with pipe connection will be installed on the inlet section of the spiral case,
suitably located and arranged for head measurements and for connection to the spiral case
pressure gauge.
The pressure taps with pipe connection will be installed at points where conditions are most
favorable for measurement of flow. The type, number, construction and location are as to meet
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Revision -
the requirements of the Winter-Kennedy method of determining discharge, for use in index
tests.
A spiral case drain connecting the lowest point of the spiral case extension with the draft tube
will be provided. The piping will be flanged on-site to the prepared spiral case drainage
connection.
3.3.2 Stay Ring and Support Ring
The stay ring will consist of the upper and the lower ring shaped deck, connected by the stayvanes forming a rigid tie across the throat of the spiral case. The streamlined stay vanes will be
of suitable number. The stay vanes will be shaped and positioned to guide the water to the
Guide Vanes.
The stay ring will be made of steel; either integrally cast or fabricated of plate and/or cast
components welded together.
It will also withstand the tension due to the internal design pressure of the spiral case.
At the bottom of the stay ring a support ring will be arranged in order to provide support during
erection and to transmit the forces into the concrete structure.
3.3.3 Pit Liner
The pit liner will be made as a welded steel plate construction. Field joints where necessary, will
be kept to a minimum in order to allow transportation within transport limits. The connection joint
between the pit liner and the stay ring will be field welded.
The pit liner serves as steel cladding of the turbine pit.
It will have recesses for two servomotors for driving of wicket gate mechanism of the distributor.
3.4 Distributor
The distributor will consist of a suitable number of moveable Guide Vanes, each consisting of a
streamlined body with stems supported through the bearings on to the head cover and the
bottom ring. The Guide Vanes will control and guide the water to the runner. The gates will be
linked via levers and links to the operating ring which will be operated by 2 oil-servomotors. The
anchorage of the servomotors is supported in the turbine pit. A gate locking device provided in
one position will ensure the position of the Guide Vanes for maintenance purposes .
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Technical DescriptionFrancis Turbine
2TFV00-0000-00718586
Revision -
3.4.1 Wicket Gate with Bearing
The Guide Vanes will be high strength chrome-nickel (13% chrome, 4% nickel) stainless steel
castings with integral stems. Each gate is supported in 3 self-lubricating guide bearings, one
located in the bottom ring in a removable cartridge and 2 in a removable cartridge block in the
head cover together with the trunnion seals. The cartridges allow a fast disassembly during
maintenance services.
3.4.2 Wicket Gate Mechanism with Operating Ring
The wicket gate mechanism will consist of the gate levers, gate links, operating ring and gate
servomotors with anchorage.
The gate lever will consist of the inner and the outer lever. The inner gate lever will be firmly
attached and dowelled to the wicket gate stem. A shear pin between the outer and the inner
lever will transfer the torque for all considered operation loads. The gate links will connect the
outer gate levers with the operating ring. The operating ring is actuated by two servomotors and
will distribute the forces and movements to all of the Guide Vanes simultaneously.
In order to protect the linkage and the gates the shear pin will break in case of excessive forcesdue to foreign material jamming between the gates when closing the distributor. A friction brake
will prevent the wicket gate from swinging freely when the shear pin is broken. The gate lever
movement will be limited by means of gate stops to prevent contact between wicket gates and
runner.
All gate mechanism bearings will be self-lubricating bushings.
The position of the operating ring will be monitored by limit switches. For visual check a position
scale will be installed on the operation ring and the head cover.
Each gate link is provided with one limit / proximity switch, to indicate occurrence of shear pinbreakage.
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Revision -
Fig. 2- Typical cross-sectional view of wicket gate mechanism
Fig. 3- 3D model of a typical gate lever
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Technical DescriptionFrancis Turbine
2TFV00-0000-00718586
Revision -
Fig.4- Typical plan view of distributor
3.4.3 Servomotor
The servomotors will provide the necessary forces to maintain the distributor in different opening
positions as required by the turbine regulating system during operation and to safely close the
distributor under any operating condition of head and load.
One number of linear transducer shall be mounted on one of the servomotor to get feedback of
servomotor guide vane movement.
Double-acting, oil-pressure operated hydraulic servomotors will be supplied, provided with
connections for the oil piping.
The servomotor support will be integrated with the pit liner. The reaction from the servomotor
will be transmitted to the surrounding concrete.
3.4.4 Head Cover
The head covers will be fabricated from steel plates. It will be of rigid construction, substantially
ribbed and designed to minimize deflections and vibration and to prevent distortion and
interference with the Guide Vanes and the gate operating mechanism under the maximum water
pressure and other forces acting including those from turbine guide bearing.
The head cover will be bolted to the machined flange of the stay ring upper deck using a
stationary seal which will seal against the stay ring upper deck.
The head cover will support the turbine guide bearing and shaft seal.
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Provisions will be made for lifting the head cover in one piece from the turbine pit through the
generator stator bore by the power house crane.
Thrust relief pipes are attached to the head cover in order to minimize the hydraulic thrust on
the runner.
Sufficient clearance for moving the runner axially will be provided.
The head cover will contain the removable cartridges for the bearings and seals of the upperwicket gate stems.
Suitable drainage passages along the nose vane will be provided in the head cover to permit
leakage water from the seals to the drainage system. Additionally, a headcover drainage pump
with all accessories will be supplied to remove any water collecting in the lower part of the head
cover.
The head cover will also be equipped with a stationary wearing ring as a counter-part to the
upper runner labyrinth seal.In the area adjacent to the wicket gate end surfaces, stainless steel
facing plates will be provided on the head cover.
3.5 Bottom Ring
The bottom ring will be fabricated from steel plates
The bottom ring will be flanged to the lower deck of the stay ring. The bottom ring will contain
the cartridges for the bearing and seal of the lower wicket gate stems. The bottom ring will be of
enough strength and stiffness, that the maximum deflection will not interfere with the Guide
Vanes or reduce the gaps of bearings to inappropriate values.
The bottom ring will also be equipped with a stationary wearing ring as a counter-part to the
lower runner labyrinth seal.
In the area adjacent to the wicket gate end surfaces, stainless steel facing plates will be
provided on the bottom ring.
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3.6 Shaft Seal
The shaft sealing system will comprise the operating seal and the standstill seal, intended to
prevent water from entering to the turbine pit, through the shaft / cover clearance.
Fig.5- Typical 3D-Modell of shaft seal
1 - Maintenance Seal 4 - Water Collecting Ring
2 - Sliding Ring 5 - Retaining Ring
3 - Seal Ring 6 - Splash Ring
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1 - Water collecting pan
2 - Support ring
3 - Holding/retaining ring
4 - Compression spring
5 - Indicating pin6 - Seal ring
7 - Seal ring inserts
(synth. material impregnated
with molybdenum)
8 - Sliding ring
9 - Shaft
10 - Stand still seal
3.6.1 Operating Seal (hydrostatic)
A water sealing system of the self-compensated hydrostatic axial type will be designed around
the shaft, positioned below the lower guide bearing, to limit the water leakage between the head
cover and the shaft.
The hydrostatic operating seal consist basically on a seal support ring, a static seal ring with a
synthetic seal ring insert and a metallic sliding ring(fixed to the turbine shaft). The static seal
insert will axially seal against the sliding ring. Filtered water will be fed into the seal ring insert
chamber between the two seal surfaces and creates a water film which acts as a hydrostatic
bearing separating the rotating sliding ring and the stationary seal ring. There is no physical
contact between the two rings and therefore theoretically no wear. Flushing purified water will
prevent any sand from entering the shaft seal surfaces, so that the wear rate for the seal ring is
very low.
The seal ring is pressed against the sliding ring by a number of stainless steel springs which
also ensure the seal function if the unit is at standstill and the lubrication water supply is
switched off. The seal is able to move axially it can easily follow any relative movement between
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Fig.6-Typical schematic view of shaft seal
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the stationary and the rotating parts of the turbine. The diameter of the seal ring is designed to
equalize forces from the water pressure acting on the seal ring, therefore the seal is not
sensitive to changing water pressures. The seal support will be bolted to the head cover.
The design will allow the inspection and replacement of the sealing components.
A wear indication for the seal ring insert shall be provided to supervise the wear, without the
disassembling of any part of the sealing housing.
3.6.2 Standstill Seal
The standstill seal will be installed between the water passage and the Operating seal. It is
intended to protect the operating seal during extended periods of standstill.
The standstill seal consists of an inflatable rubber profile which applies to the shaft when
pressurized, thus sealing off the water passage. When being relieved, the water pressure of the
water passage pushes back the sealing lips from the shaft.
The seal must be applied only when the turbine is stopped. It is applied manually by operating
the control valve. A limit switch on the operating valve prevents the turbine from being started,when the standstill seal is applied. The operating valve will be secured with a padlock.
The air to inflate the standstill seal will be taken from the compressed air system. If necessary a
pressure reducing valve will be provided to reduce the air pressure to a value applicable for the
standstill seal.
3.7 Draft Tube
The draft tube will be of the elbow type. The draft tube will consist of the draft tube cone and the
draft tube liner. The draft tube cone will be bolted to the bottom ring at upper side and to the
draft tube liner at lower side.
The draft tube lining will be a welded steel plate assembly. To facilitate transportation it may be
sectionalized for field welding. Because of its rigid design with outside stiffening rings and ribs
and concrete reinforcements the draft tube will withstand safely pressure variations and
pulsations under all operation conditions.
The draft tube liner will have a suitable number of pads and connections for the application of
jacks or leveling screws and tie rods during field erection. The draft tube will have a steel lining
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ICB No. - GBHHPL/ICB-002/LOT 3
3 x 60 MW BAJOLI HOLI HE Project
Technical DescriptionFrancis Turbine
2TFV00-0000-00718586
Revision -
until 5 m distance from turbine center line. From there the draft tube will be shaped in concrete
according to the requirements given by the hydraulic neat line.
The draft tube will rest on solid foundation and bracing during embedment. Fixations will be
designed to support and position the draft tube during all conditions of installation and
concreting.
The cone will be split in two parts with dismantling joint to facilitate runner removal from bottom.
The draft tube cone will also provide access to the draft tube inside via a man-door to enable
inspection and maintenance service. The inner surface of the man door cover will conform tothe interior contour of the draft tube liner. A test cock will be provided below the sill of the door.
The upper portion of the draft tube cone directly below the runner will be made from stainless
steel with an extension of approx. 500 mm.
A steel drain box will be provided in the liner at the lowest point of the draft tube, protected by a
suitable and removable inlet grating. A connection for the spiral case drain pipe will be provided.
A connection for the thrust relief pipe will be provided.
One set of pressure taps with pipe connection will be installed.
3.8 Bearing
3.8.1 Guide bearing
The turbine guide bearing will support the turbine shaft and will be designed for radial forces
originated from the turbine runner. The radial forces will be transferred via bearing housing,
head cover and stay ring into the civil structure.
The turbine guide bearing will be of the segmented, adjustable, multiple-shoe, self-lubricated
type. The shaft is running on the bearing pads. The segments are machined in a way to self
adjust to the optimum position with respect to load and circumferential speed.
The bearing elements are lined with a high-grade anti-friction Babbitt metal securely anchored
to the bearing backing.
The guide bearing will be located above the shaft seal and will be as near as possible to the
runner and will consist of a bearing support or housing and removable bearing elements.
It will permit axial movement of the shaft.
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GMR Bajoli Holi Hydro Electric Project (180MW)Techno-Commercial Bid Document
ICB No. - GBHHPL/ICB-002/LOT 3
3 x 60 MW BAJOLI HOLI HE Project
Technical DescriptionFrancis Turbine
2TFV00-0000-00718586
Revision -
The oil circulation will be of the self-lubrication type by the action of the shaft rotation. An oil
reservoir of sufficient capacity to contain all the oil required by the bearing lubrication system is
provided around the bearing. The bearing reservoir is an integral part of the bearing housing.
Cooling of bearing oil will be done by an internal coolers placed in oil reservoir
3.9 Accessories
Working, operating and inspection walkways and platforms complete with non-slip type floor
plates, stairs, ladders and hand railings will be furnished where necessary or desirable in theturbine pit. All pit walkways, platforms, stairways and equipment will be easily removable.
A circular crane will be supplied inside the turbine pit, for assembly and disassembly of turbine
components. This crane will be located below the generator lower bracket and will be integrated
by a manual chain hoist, a manual trolley and a steel structure that allows the movement of the
hoist over the entire turbine pit area.
A runner trolley will be supplied to facilitate runner removal from bottom side.
An inspection platform will be furnished to facilitate inspection and maintenance of the runner.
The platform will extend over the cross-sectional area of the draft tube where it is installed. It willbe made of prefabricated, light weight components in suitable sections so as to be easily
transported into the draft tube. Provisions will be provided on the draft tube cone for supporting
the maintenance platform.
Parts for pressure tests will be included in the scope of supply as far as required for field tests.
Oil for first filling of the governor pressure oil systems and for the turbine bearings with 10% as
extra will be supplied.
3.10 Installation Device
All special tools required for normal operation and maintenance will be supplied. It shall be as
per tender specifications(PTS-Turbine and accessories). However, those which are common
with other part specifications shall not be doubled.
4 Materials
For all major parts, material are listed in turbine datasheet submitted with bid. The materials
might be subject to changes according to market availabilities. Equivalent materials may be
used. All used materials will be of accepted national or international standards and of proven
reliability for the intended purpose.
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ICB No. - GBHHPL/ICB-002/LOT 3
3 x 60 MW BAJOLI HOLI HE Project
Technical DescriptionFrancis Turbine
2TFV00-0000-00718586
Revision -
5 Spare Parts
All spare parts to be supplied will be identical to the ones originally installed, of the same
material and manufacture process. All spare parts will be packed not to be damaged during
storage. All boxes will be marked for identification.
All applicable spare parts as listed under mandatory spare parts of tender document shall be
included in scope.
6 Instruments and Control Equipment
The turbine will be provided with supervisory instrumentation and protective devices, as
necessary for complete operation with a high degree of safety, reliability and continuity of
service. All necessary electrical wiring and piping materials within the turbine and in the turbine
gallery from the pick-up points to the instrumentation board or terminal blocks outside the
turbine pit will be provided.
Cabling will be neatly arranged and designed to allow the maintenance of the turbines without a
major disconnecting work.
7 Transportation, Erection and Commissioning
The transportation of the turbine equipment is in the scope of the turbine supplier.
The customer has to provide storage areas and erection bays with sufficient space as per
requirements.
Concrete support outlines for the draft tube liners, spiral case, pit liner and any other concrete
supporting structures required will be communicated by the turbine supplier and provided by
others in the first stage concrete to suit the turbine design. The turbine supplier will furnish and
install all supporting columns, jacks, leveling screws, tie rods and turn-buckles.
All parts will be firmly secured in position to ensure that no movement takes place during
placing of concrete and grout.The speed of concreting will be max. 0.5 m/h of elevation unless otherwise specified on the
respective equipment drawing. The depth of liquid state of concrete for calculation of buoyant
forces depends on the curing time of the cement at the prevailing temperatures.
The shipping sections of draft tube liners, spiral case and pit liner will be assembled as required/
applicable. All the necessary bracings and stiffeners inside the draft tube required to maintain
the shape and locations of the parts during concreting and curing will be supplied and installed.
After curing of the concrete all such provisions will be removed and disposed of.
Before installing the removable part, all parts will be thoroughly cleaned of rust and protective
coatings, and all burrs and nicks will be removed.
Sub-assemblies will be carefully fitted together.
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3 x 60 MW BAJOLI HOLI HE Project
Technical DescriptionFrancis Turbine
2TFV00-0000-00718586
Revision -
The turbine manufacturer will indicate the largest and heaviest turbine components to be
shipped / handled at site.
During erection of each turbine and all its auxiliaries, the turbine supplier will test the turbine,
governor and accessories in accordance with the requirements of the IEC and other agreed
standards.
Prior to taking each unit into commercial operation, commissioning tests will be performed on
each completed turbine unit.
The tests will be coordinated with the tests of the governor, generator and other equipment.
The wire testing and function testing of signals between the turbine equipment at one side andthe control- and protection equipment at the other side will be directed by the responsible party
for field testing and commissioning of the control systems. The party responsible for the field
testing and commissioning of the turbine equipment will participate in these tests as necessary
to thoroughly test the wiring and functions of all signals related to the turbine equipment.
The turbine supplier will provide all necessary labor and instruments to perform the tests.
8 Tests
8.1 Shop Assembly and Tests
The turbines will be assembled in the shop to verify the design, construction, machining for
proper alignment, fits and clearances to the extent practical. Parts will be properly match-
marked, identified and doweled to assure correct assembly and alignment in the field.
Critical dimensions and small clearances of the assemblies will be measured and recorded on a
shop inspection sheet.
8.2 Field Tests
The pre-commissioning tests will include, but not be limited to:
Pressure tests on all pressure oil piping (in connection with the governor equipment) and all
pressure piping systems will be hydrostatic tested at a pressure of 1.5 times higher than the
maximum operating pressure after installation for a minimum of 1.5 hours ( if already not
tested at works).
Measurement of mechanical clearances, levels, strokes and other measurements
Functional tests of all auxiliaries and protective devices
Operation of governor hydraulic units.
Functional operation of the gate operating mechanism in the dry condition
Operational tests of turbine bearings
Start - stop sequences test in the dry
The commissioning tests will include, but not be limited to:
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GMR Bajoli Holi Hydro Electric Project (180MW)Techno-Commercial Bid Document
ICB No. - GBHHPL/ICB-002/LOT 3
3 x 60 MW BAJOLI HOLI HE Project
Technical DescriptionFrancis Turbine
2TFV00-0000-00718586
Revision -
Alignment and rotation checks in the dry
Mechanical run
Governor operation
Guide Vane function test
Timing tests including measurement of guide vane openings
Initial no-load wet run to ensure satisfactory operation of auxiliary equipment
Bearings test run
Checking of interlocks and indications
Tripping tests for turbine Load rejection and load acceptance tests
8.3 Field Efficiency Tests
A thermodynamic test at one turbine will be carried out to conduct the efficiency and capacity of
the turbine as per the IEC 60041.
The power output and efficiency tests on the turbine will be made at net effective head as near
as practicable to the rated head if actual conditions allow. The turbine capacity will be
determined from electrical measurements of generator output corrected for generator losses.
The generator losses will be determined from generator efficiency curves and verified by
measurement of air cooler and bearing heat loads.
9 Training
The operators personnel will receive instruction in operating the equipment while the
commissioning of the first unit is performed ( as per contract documents).
10 Operation and Maintenance
Operation manuals and maintenance manuals will be provided before commissioning phase.