Piping Basis
Transcript of Piping Basis
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DESIGN BASIS REPORT
FOR
PIPING
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REVISION STATUS SHEET
REV. DETAILS / DESCRIPTION DATE
A Preliminary issue for comments 24 – 07 - 01
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PIPING DESIGN BASIS
1.0 SCOPE
2.0 CODES & STANDARDS
3.0 DESIGN CRITERIA
4.0 MATERIALS
5.0 VALVING
6.0 GENERAL
7.0 THERMAL INSULATION
8.0 PAINTING
9.0 PROCESS DESIGN CRITETIA FOR PIPING
ANNEXURE - A PIPING MATERIAL SELECTION ANNEXURE - B MATERIAL SELECTION CHART ANNEXURE - C VALVE DATA SHEETS
ANNEXURE - D SCHEDULE OF THICKNESS FOR THERMAL INSULATION
ANNEXURE - E DESIGN PROCEDURES FOR PIPE SUPPORTS ANNEXURE - F STRESS ANALYSIS DESIGN CRITERIA ANNEXURE - G MAJOR REQUIREMENTS OF IBR
ANNEXURE - H ACCESSIBILITY REQUIREMENTS OF VALVES & INSTRUMENTS
ANNEXURE - I RECOMMENDED VELOCITY RANGE FOR
VARIOUS FLUIDS
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1.0 SCOPE: 1.1 This specification describes the basis for the overall design of steam, water & utility
piping of the power plant. It is intended to establish designs confirming to codes and accepted practices currently applicable to piping systems.
2.0 CODES & STANDARDS: 2.1 The main design codes and standards, which shall be considered as minimum
requirements are listed below. Latest version of these shall be followed. ANSI / ASME B31.1 - Power Piping ANSI B16.5 - Steel Pipe Flanges and Flanged Fitting
ANSI B16.9 Factory - made wrought steel butt-welding Fitting
ANSI B16.10 - Face-to-Face & End-to-End Dimensions of
Ferrous Valves
ANSI B16.11 - Forged Steel Fittings, Socket Welding and Threaded
ANSI B16.34 - Valves - Flanged and butt-welding ends
ANSI B16.20 - Ring Joint gaskets and grooves for Steel pipe Flanges
ANSI B16.25 - Butt Welding Ends ANSI B36.10 - Welded and seamless wrought steel pipe ANSI B36.19 - Stainless Steel Pipe ANSI B16. 21 - Non Metallic Flat Gaskets for Pipes Flanges ANSI B 18.2.1 - Square and Hexagonal Bolts ANSI B 18.2.2 - Square and Hexagonal Bolts API 590 - Spectacle Blind for Sizes up to 24” EJMA - Expansion Joints
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API 594 - Wafer type Check Valves API 598 - Valve Inspection Test API 601 - Metallic Gaskets for Piping API 602 - Compact Carbon Steel Gate Valves API 609 - Butterfly Valve 150 Psig AWWA C 504 - Rubber Seated Butterfly Valves BS 5146 - Inspection and Testing of Steel Valves BS 5155 - Cast iron & Carbon Steel Butterfly Valves BS 5351 - Steel Ball Valves BS 5352 - Forged Steel Globe & Check Valves MSS SP 6 - Standard finishes for contact surfaces MSS SP 25 - Standard marking system for Valves, Fittings & Flanges
MSS SP 43 - Wrought Stainless Steel Butt welded Fittings
Mild Steel Tubes - IS-1239 (I) - IS-1239 (II) - Steel Fittings
IS-3589 - Seamless or Electrically welded steel pipes for Water, Gas, & Sewage (168.3 to 2032 mm Outside diameter)
MSS-SP-58 - Pipe Hanger & Supports Materials Design & Manufacture
In addition to the above the following specifications shall form part of this project. Technical Specification for Hot Insulation Technical specification for Shop & Field Painting
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Piping Material Specification Valve Material Specification Fabrication and Erection of Piping Inspection, Flushing, & Testing of Piping Pre commissioning & chemical cleaning Non- Destructive examination 2.2 Boiler Code Piping: a) 1995 ASME boiler and pressure vessel code Sec. I and Sec. VIII apply to certain
integral portions of steam, feed water and blow-off piping associated with boilers and steam generating equipment, as defined by that code.
b) Certain portions of external piping shall meet the requirements of ANSI B31.1,
(1992) Power Piping Code, as defined by that code. c) Steam and Feed water piping coming under the purview of the Indian Boiler
Regulations shall be designed in accordance with that code. Annexure-G lays down the major requirements of Indian Boiler Regulations. Nevertheless, requirements spelt out in respective ASME / ANSI codes shall be adhered to, as a minimum.
3.0 DESIGN CRITERIA: 3.1 Operating Conditions: 3.1.1 Design conditions of pressure and temperature will be the most severe conditions
expected to co-exist under long-term operating conditions. These usual operations include all functions such as throttling, blowing and bypassing likely to be used for operation and control.
3.1.2 Temporary Conditions: Usual operating conditions do not include more severe temporary conditions, such as
those abnormal operations like turbine over speed / over pressure conditions, as long as the duration and parameters do not exceed the values defined in the respective codes.
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3.2 Design Temperature: Design temperature is the most severe sustained fluid temperature, subject to
conditions of section 3.1 above. Design temperature will be usually the maximum fluid temperature.
3.3 Design Pressure: The Design pressure of piping shall be the most severe condition of internal or
external fluid pressure, subject to conditions of Section 3.1 above arrived at in conjunction with the following considerations.
- Design pressure of the equipment to which it is connected. - Set pressure of safety valve which protects the system. However, Piping systems operating under vacuum / likely to be operated under
vacuum shall be designed for full vacuum, also. 3.4 Design Life: Piping system shall be designed for 7000 cycle based on the plant life of 30 years,
such that it operates without replacement and with normal maintenance, and shall withstand the fluctuations in operating parameters and cycling, normally expected.
3.5 Piping Flexibility: All piping must be designed for thermal expansion under start-up, operating and shut
down conditions such that the actual stresses shall be well within the allowable limits of the pipe material and the forces / moments on the equipment shall be within the limits defined by the equipment supplier.
Provisions for expansion or contraction shall normally be made with bends, offsets
and expansion loops. Expansion joints may be used on large diameter piping, relief systems or where they are acceptable process wise and economically justified.
Stress analysis shall be done for piping meeting the conditions specified in the stress
analysis design criteria attached as Annexure-F. 3.6 Piping Supports: All piping shall be adequately supported, guided or anchored so as to prevent undue
vibration, deflection or loads on connected equipment & piping and leakage at joints. Piping at valves and equipment such as heat exchangers and pumps, requiring periodic maintenance, shall be supported in such a way so that the piping can be detached with a minimum temporary supports.
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The Design and Selection of supports shall be based on Design procedures for pipe
supports attached as Annexure-E. 4.0 MATERIALS: 4.1 Piping Material Selection: Piping material selection attached as Annexure-A includes line service, pipe material,
type of construction and ANSI Rating. Piping Material Selection for this project is attached as Annexure-A. The basis for material selection is as per Material Selection Chart attached as Annexure - B.
4.2 Corrosion Allowance: 4.2.1 Unless otherwise specified in piping material specification, minimum corrosion
allowance, as shown below, shall be provided for all non-IBR piping systems. Carbon Steel 1.5mm Ferritic Alloys 1.5mm Austenitic Steel 0mm Non - Ferrous 0mm 4.2.2 For IBR piping, refer to the requirements under the IBR regulations. 4.3 Wall Thickness and Reinforcement: 4.3.1 Reinforcement requirement for nozzles / stubs or other welded branch connections
shall be as per Section 104.3 of ANSI B31.1 and shall additionally meet the requirements of IBR for piping systems under the purview of IBR.
4.4 Line and Connection Size: Minimum line size shall be 1” for long runs in the offsite area. Exceptions are there
for instrument piping, which may be minimum 1/4”. Vents and Drains shall be 3/4” min. Pipe sizes 1-1/4”, 2-1/2” and all other odd sizes such as 5” and 7” shall not be used unless required to match the connections to Mechanical equipment.
4.5 Bends & Mitres: 4.5.1 Long radius welding elbows shall be used for changes in direction of piping. For
steam and feed water piping coming under the purview of the Indian Boiler Regulation bend radii shall be as per that regulations. Short radius bends shall only be used where space does not permit the use of long radius elbows and bends.
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4.5.2 Welded mitre bends, with a maximum included angle of 22.5° per segment, may be used in utility piping systems, for sizes NB 350 and over, where the pressure and temperature does not exceed 10 kg/cm2 and 120°C respectively. In other services &
Higher-pressure conditions, the welded mitre bends may be used, provided they meet process requirements.
5.0 VALVING: 5.1 Valves: 5.1.1 Design, fabrication and testing of valves shall generally conform to ANSI B16.34
(1981). Butterfly valves shall conform to AWWA C504. 5.1.2 All valves requiring attention during normal operation shall be accessible either from
grade, platform or Ladders. 5.1.3 All valves shall be suitable for installation in horizontal as well as vertical pipeline. 5.1.4 All globe valves shall be capable of being closed against the design pressure. Where
globe valve has been specified for regulation purpose, the disc shall be tapered plug type and suitable for controlling throughout its lift.
5.1.5 All gate and globe valves shall have bonnet back seating arrangement to facilitate
easy replacement of packing with the valves in service. 5.1.6 All gate, globe and check valves shall be designed for reconditioning seating surfaces
and replacement of stem and disc without removing the valve body from the line. 5.1.7 Manual gear operators shall be provided to open / close the valve against the
maximum differential pressure across the valve such that the effort required to operate does not exceed 25 kgf.
However, unless otherwise stated in P&ID, geared operators shall be provided as below:
- Gate and Globe valves ANSI #150 with size 12” & larger ANSI #300 with size 8” & larger - Ball valves ANSI #150 with size 8” & larger ANSI #300 with size 6” & larger - Butterfly valves ANSI #150 with size 8” & larger 5.1.8 All gate and globe valves of size 50 mm and below in vacuum services shall have
extra deep gland packing without any provision for water gland sealing.
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5.1.9 All gate and globe valves of size 80 mm NB and above in vacuum services shall have
adequately deep gland packing and shall be equipped with lantern rings to admit pressurised water for gland sealing.
5.1.10 Integral bypass valves shall be provided for all gate valves as classified below. Size
and location of bypass valve shall be as per MSS-SP-45.
a) Under pressure class of 600 lbs and above, where the sizes are 100 mm NB and above
b) Under pressure class of 300 lbs and 400 lbs where the sizes are 250 mm NB and
above. 5.1.11 Valve Data Sheets attached as Annexure - C gives a basis of valve selection for the
different systems 5.1.12 Valved drains, vents shall be installed at low and high points in piping systems, if
required for operation, maintenance or for draining purposes. 5.1.13 Drains & vents required purely for hydraulic or pneumatic test purposes are to be
shown on the isometric drawings and added to the P&ID’S by the Piping erection contractor.
To collect samples for laboratory analysis, dedicated sample connections are required; sample points shall not be located in dead ends of piping.
6.0 GENERAL: 6.1 General Layout Requirements: Pipes of sizes 80 mm NPS and above shall be shop fabricated as per the drawings and
pipes of sizes 50 mm NPS and below shall, in general, be field routed. 6.2 Accessibility: For accessibility requirement of Valves & Instruments for the plant refer Annexure-H
of this specification. 6.3 Pipe Routing: 6.3.1 All Piping entering and leaving a plot area shall be grouped together as far as
practicable. Inside plot piping shall be routed on overhead pipe bridges wherever possible.
6.3.2 Piping with Instrument connections shall be routed to ensure accessibility, if
necessary Platforms / Walkways shall be provided.
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6.3.3 Fire fighting water lines, if installed above ground shall not run along pipe bridges
and pipe racks but as practical along roads. 6.3.4 The elevations of overhead piping shall be as specified by the site requirements but
never be less than - 6.8 M over Railroads / Railways - 6.0 M over Main roads - 6.0 M for crane access - 4.0 M for truck access - 3.0 M for fork – lift truck access - 2.2 M over Walkways inside buildings and Platforms.
6.3.5 The minimum horizontal clearance shall be 0.75 M for access ways and walkways,
however the minimum clearance shall be 0.9 M for frequently used main passages. 6.3.6 Buried Piping shall be considered for
- Drainage or Sewerage. - Fire water lines.
6.3.7 Buried piping shall have a minimum cover of soil: - Fire water lines (main) - 0.9 M - Road crossings for lines 24” & smaller - 0.6 M
6.3.8 The load on the pipes should be equalized for lines crossings railroads / railways and traffic roads by means of pipe sleeves or a culvert. The pipes shall be kept centrally in the sleeves by distance pieces welded to the pipe or fixed to the sheeting if the line is insulated.
6.3.9 As far as practical, piping shall run at the different elevations designated for north-south and east-west banks and shall change elevation at change in direction.
6.3.10 Sleeves or holes through walls, floors of buildings shall have a size permitting the
passage of a flange of the relevant pipe size to facilitate the installation of fabricated piping and to permit insulation work.
6.4 Relief System / Blow down system Piping:
Relief valve discharging steam, air directly to atmosphere shall be equipped with drain or suitably piped to prevent accumulation of liquid at valve outlet. Relief valve discharge piping shall be taken to safe location as per following
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- 3 M above top platform of column or structure - 25 M horizontally away from Boiler. - 50 M horizontally away from Boiler, if more than more one-relief system of
different set pressures is discharging into one common riser of vent stack.
Inlet and outlet piping of pressure relief valve shall be adequately supported to take care of the thrust induced by the relief valve during popping.
6.5 Offsite and Yard Piping: In general, the Pipes shall be laid at grade level on sleepers at 300mm higher from
grade level. Pipes at crossing of roads shall be by pipe-way bridges in general. Pipes sleeves may be considered where one or two pipes are to cross the road.
6.6 Expansion and Contraction: Piping systems shall have sufficiently flexibility to allow for thermal expansion and
contraction so as to prevent
- Failure of piping components owing to over stress leakage at joints. - Excessive thrusts and moments on connected equipment anchor points etc. - Forces on equipment connection nozzles, in case where the forces exceed normal
conservative values.
Loops and offsets shall provide for flexibility in piping systems, especially for noxious or hazardous fluids, Expansion joints shall be considered when limited space will not give sufficient flexibility. Expansion joints shall be used only with adequate guided and anchors. Loops and offsets shall be used in preference to bellow type expansion joints wherever possible. Bellow type joints shall not be subjected to torsional loads. Horizontal piping expansion loops on pipe bridges shall have vertical offset to stay clear of adjacent piping and any thermally expanded piping shall be anchored at the plot limit. Calculations shall establish stresses, forces and moments. Pipe stress / flexibility analysis shall be executed with program: CEASAR II from COADE
7.0 THERMAL INSULATION: 7.1 Thermal insulation shall be provided for all piping and equipment with surface
operating temperatures of 60°C or above for one or more of the following reasons:
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a) Conserve heat
b) Maintain temperature for process control c) Provide for personnel protection. 7.2 Design basis for selecting insulation thickness shall be as below: Ambient Temperature : 40°C Cladding Temperature : 60°C (max) Wind Velocity : 0.5 m / sec. Emissivity of Cladding : 0.15 Hot Surface Temperature : Fluid Design Temperature 7.3 Insulation material for hot insulation shall be as below:
i) For sizes (including insulation thickness) up to 350 mm, Rock wool preformed pipe sections of density 144 kg/m3 conforming to IS: 9842
ii) For sizes 400 mm and above: In order to meet the sizes above
400mm, (Including insulation thickness) lightly resin bonded mattress confirming to ASTM C547 class III shall be applied in addition to the Rock wool preformed pipe sections.
iii) The physical requirement of bulk density and chloride content, thermal conductivity and PH value of the material shall be as follows:
Bulk Density : 140 kg / cubic. Meters Chloride content : 20 PPM Thermal conductivity: 0.43 m W/cm deg. C for mean temp 50 deg. C
0.52 m W/cm deg. C for mean temp 100 deg. C 0.62 m W/cm deg. C for mean temp 150 deg. C 0.68 m W/cm deg. C for mean temp 200 deg. C 0.80 m W/cm deg. C for mean temp 250 deg. C 0.90 m W/cm deg. C for mean temp 300 deg. C
7.4 Aluminum cladding shall be used as a weather protection over insulation unless
otherwise specified and shall conform to ASTM - B - 209 - 1060 Temper H-14. 7.5 Schedule of thickness for Thermal Insulation is attached as Annexure - D. 8.0 PAINTING: 8.1 Painting of pipe work shall be as per the painting specification. The procedures for
painting of insulated and non-insulated pipes, the colour codes, the method of painting, etc. shall comply with the guidelines specified in the painting specification.
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9.0 PROCESS DESIGN CRITERIA FOR PIPING 9.1 General: The complete CPP piping shall mainly consist of following systems; viz. Boiler
feed pump suction piping, boiler feed pump discharge piping, boiler feed pump recirculating piping, main steam piping, auxiliary steam piping, extraction steam piping, condensate piping, Raw Water piping, DM Plant piping, fire water piping, boiler blow down, vents, drains, etc. and low pressure utility piping.
9.2 Boiler Feed Pump Suction Piping: A common suction line from deaerator/ feed water storage tank shall be provided
with branching off lines to individual boiler feed pumps. The common suction line of BFP’s shall be designed for rated flow of the operating BFP’s + minimum recirculation flow of the standby BFP and the branch off line shall be designed for the rated flow of the pump.
9.3 Boiler Feed Pump Discharge Piping: The discharge of boiler feed pumps shall be connected to the common discharge
header. From the discharge header feed water piping shall be routed to the steam generator through, hp heater and feed water control stations. The feed water control station shall have 1 x 100% and 1 x 40% control valves having flexibility in operating the Boiler at varying load conditions. Feed water required for super heater attemperation of the steam generators and other desuperheaters for auxiliary steam in the power plant shall be tapped from the discharge headers of BFP’s.
9.4 Boiler Feed Pump Recirculation Piping: Separate recirculation line for each boiler feed pump shall be provided from the
non-return-cum modulating recirulation valves (Automatic Recirculation Valves) with necessary isolation valves and pressure break down orifices and shall be connected to the deaerator. Though the pressure reduction is achieved mainly through the recirculation valve, the upstream of the pressure break down orifice located near deaerator shall be kept 3 to 4 kg/cm2 above the deaerator pressure so as to avoid flashing of water in the recirculation line thereby avoiding water hammer and vibrations in the recirculation lines.
9.5 Main Steam Piping, Auxiliary Steam Piping and Extraction Steam Piping: The main steam lines constitute the most important piping in a power plant and the
main steam piping from the boiler is connected to the turbine with adequate expansion loop(s) to take care of the thermal expansions & to obtain adequate flexibility so as not to exceed allowable reactions on boiler & turbine connections.
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Three separate extraction piping will be provided from the turbine to the H.P. Heater, Deaerator and L.P. Heater to supply the steam. In order to meet the transient condition, separate tap off will be provided from the main steam line to the Deaerator extraction line through the Desuper Heater. Another tap off will be provided in the main steam line to meet the steam requirement of turbine gland steam ejector system.
Desuperheater spray requirement for auxiliary steam Desuperheaters and
superheater attemperators will be met by tap offs from the feed water pump discharge header. On all pressure part tapping joints, 2 root valves shall be provided in series.
9.6 Condensate Pump Suction Piping: The common suction line from condenser hot well shall be connected to individual
condensate extraction pumps through branch lines and expansion joints. The piping shall be sized for the maximum flow to the condenser under various modes of plant operation.
9.7 Condensate Pump Discharge Piping: The discharge from the condensate pumps shall be connected and fed to the
deaerator through ejector, gland steam condenser, drain cooler and L.P heater. A tapping shall be provided for supplying spray water to turbine exhaust hood to control the temperature. At the condensate outlet of GSC a minimum recirculation line shall be taken and this will be directly connected to condenser to control the level of the condenser.
9.8 Boiler Blow Down, Vents, Drains Etc. Blow down piping shall connect the drains from boiler drum, super heaters, bottom
ring headers, etc. with the blow down tank. Pressure breakdown orifices shall be provided before the blow down tank nozzle. Some high-pressure steam line drains from different piping and equipment are connected to flash tank while others shall be let off to the plant drains.
9.9 Low Pressure Utility Piping: The low-pressure utility piping shall cover the following services.
1. Make-up water 2. Instrument air 3. Service air 4. D.M.water 5. Fuel oil-HSD 6. Service and potable water 7. Cooling water 8. Auxiliary cooling water
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9. Raw water
9.9.1 Make up Water Piping: Makeup water for the power plant shall be supplied from raw water reservoir. From
the raw water reservoir, raw water shall be pumped for cooling tower make up, the DM plant requirement, air-conditioning ventilation system and service/drinking water.
9.9.2 Instrument Air: The instrument air shall be supplied through pipes from the common compressor
house located in the power plant. The header shall be run throughout the power plant to meet all instrument requirements. Tapping for control valves in the deaerator area, feed water control station etc., and for other instruments shall be made from the header at all the nearest points.
9.9.3 Service Air: The service air shall be supplied from the compressor house through service air
pipes. The header shall be routed through out the power plant. Tappings shall be made from this header for various plant locations in Boiler area. STG building, coal handling plant area as per the distribution list given in Compressed Air DBR.
9.9.4 DM Water: The DM water piping from DM plant to the DM water storage tank and from the
storage tank to deaereator and other areas of requirement such as initial filling for condenser hot well, H.P. and L.P. Dosing system will be routed through suitably sized pipeline.
9.9.5 HSD: Fuel oil pipeline shall be routed from the storage tank to boiler through transfer
pumps. 9.9.6 Potable Water: Potable water pipe lines shall be routed separately throughout the power plant. The
material of potable water pipe shall be carbon steel conforming to IS: 1239 black and galvanized.
9.9.7 Cooling Water:
The cooling water system shall be supplying cooling water to the condensers of the steam turbine generators of the power plant.
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The common supply header and return header shall be buried along the T.G.
building for the turbine condenser. The buried piping shall be provided with suitable external coating and wrapping.
Motor operated butterfly valves shall be installed at the discharge of each CW
pump. Gear operated butterfly isolation valves shall be installed on the return header at the cooling tower inlet. CW pump suction piping shall have rubber expansion bellows.
The butterfly valves shall conform to API 609 or AWWA C504 standards and
flanged type and shall be of cast steel body and disc with nitrile rubber seating. 9.9.8. Auxiliary Cooling Water: The auxiliary cooling water header shall be routed along with the main cooling
water piping. From the header branch lines for lube oil coolers, generator air coolers, ash handling system compressors and plant air compressor and sample coolers etc. The return piping shall be routed to cooling tower inlet header. The material of construction shall be same as that of cooling water piping.
All piping to the coolers shall be provided with isolation valves of gate type at inlet
and globe valve, at outlet. 9.9.9. Raw Water: Raw water piping shall be routed from the existing raw water Reservoir (UMI) to
the proposed CPP raw water reservoir. The Raw water piping shall be buried at 1.5 m below the ground. The material of
piping shall be carbon steel as per IS: 3589 ERW pipes. The buried piping shall be provided with suitable external coating and wrapping.
9.10 Fire Water Piping: Firewater piping shall involve piping for the fire hydrant system and high velocity
water spray systems. Fire hydrant piping shall be routed from the fire water pumps to various hydrant
valve locations, the yard piping mainly being buried piping with suitable wrapping and coating. The hydrant piping shall be ring main type (close loop system) so that leakage/breakage at one location would not render the total system non-operational. Suitable isolation valves, drains connected at all low points shall be provided.
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9.11 Optimum Line Sizing: Following parameters for each service have been considered to arrive at optimum
line size:
a) Type of fluid, its properties under design condition. b) Design flow rate c) Recommended velocity d) Pressure at source and receiver ie., available pressure drop through the lines
including fittings, valves and specialities such as strainers, flow elements etc. For pumps, in addition to friction losses, static head is also considered while
estimating total pressure head required. Annexure - I, gives the recommended velocity range, for various fluids.
ANNEXURE - A
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PIPING MATERIAL SELECTION
System Design
Temperature
Design Pressure
Flange / Valve
Pipe Material
Construction
° C BAR(a) Rating(ANSI)
LIVE STEAM 500 66.89 900 ASTM- A335 Gr.P22
SEAMLESS
LP EXTRACTION STEAM 157.5 2.13 150 ASTM-A106 Gr.B
SEAMLESS
IP EXTRACTION STEAM 202.7 6.2 150 ASTM-A106 Gr.B
SEAMLESS
HP EXTRACTION STEAM 330.5 18.52 300 ASTM-A106 Gr.B
SEAMLESS
BOILER FEED WATER PUMP SUCTION
145.5 6.0 150 ASTM-A106 Gr.B
SEAMLESS
BOILER FEED WATER PUMP DISCHARGE
202.0 125.2 900 ASTM-A106 Gr.B
SEAMLESS
CONDENSATE PUMP DISCHARGE (AFTER LEVEL CONTROL STATION)
116.2 8.3 150 ASTM-A106 Gr.B
SEAMLESS
LP HEATER DRAIN 119.4 2.0 150 ASTM-A106 Gr.B
SEAMLESS
HP HEATER DRAIN (BEFORE C.V STATION)
155.1 17.5 300 ASTM-A106 Gr.B
SEAMLESS
HP HEATER DRAIN (AFTER C.V STATION)
155.1 13.0 150 ASTM-A106 Gr.B
SEAMLESS
DEAERATOR OVERFLOW & BLOW
145.5 6.0 150 ASTM-A106 Gr.B
SEAMLESS
LINES TO DRAIN MANIFOLD 330.5/202.7, 151.5
18.52/6.20, 2.13
300/150 ASTM-A106 Gr.B
SEAMLESS
COOLING WATER SUPPLY 50 5 150 IS: 1239 IS: 3589
ERW ERW
COOLING WATER DISCHARGE 50 5 150 IS: 1239 IS: 3589
ERW ERW
INSTRUMENT AIR 50 10 150 IS: 1239 GALV IS: 3589 GALV
ERW ERW
SERVICE AIR 50 10 150 IS: 1239 ERW
DEMINERALISED WATER 50 14 150 ASTM-A312, TP-304
SEAMLESS
RAW WATER 50 4.8 150 IS: 1239 IS: 3589
ERW ERW
POTABLE WATER 50 4.8 150 IS: 1239 GALV IS: 3589 GALV
ERW ERW
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ANNEXURE - B
MATERIAL SELECTION CHART
MATERIAL CARBON CONTENT DESIGN % TEMPERATURE °C
SEAMLESS PIPES ASTM A106 Gr.B 0.30 Max. 427 ASTM A335 Gr.P1 0.10 - 0.20 468 ASTM A335 Gr.P11 0.15 Max. 570 ASTM A335 Gr.P22 0.15 Max. 600 ASTM A312 Gr.TP304 0.08 Max. -200 to 500 ASTM A312 Gr.TP304L 0.035 Max. -200 to 500 WELDED PIPES ASTM A672 Gr.B60 0.30 Max. -46 to 300 API 5L Gr.B (ERW ; E = 0.85) 0.20 Max. 230 ASTM A312 Gr.TP304 0.08 Max. -200 to 500 ASTM A312 Gr.TP304L 0.035 Max. -200 to 500 FITTINGS ASTM A234 Gr.WPB 0.30 Max. 427 ASTM A234 Gr.WP1 0.10 - 0.20 468 ASTM A234 Gr.WP11 0.15 Max. 570 ASTM A234 Gr.WP22 0.15 Max. 600 ASTM A403 Gr.WP304 0.08 Max. -200 to 500 ASTM A403 Gr.WP304L 0.035 Max. -200 to 500 FORGINGS ASTM A105 0.35 Max. 427 ASTM A182 Gr.F1 0.28 Max. 468 ASTM A182 Gr.F11 Cl.1 0.10 - 0.20 570 ASTM A182 Gr.F22 Cl.1 0.15 Max. 600 ASTM A182 Gr.F304 0.08 Max. -200 to 500 ASTM A182 Gr.F304L 0.035 Max. -200 to 500
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MATERIAL CARBON CONTENT DESIGN % TEMPERATURE °C
CASTINGS ASTM A216 Gr.WCB 0.30 Max. 427 ASTM A217 Gr.WC1 0.25 Max. 468 ASTM A217 Gr.WC6 0.20 Max. 570 ASTM A217 Gr.WC9 0.18 Max. 600 ASTM A351 Gr.CF8 0.08 Max. -105 to 538 BOLTS ASTM A193 Gr.B7 0.37 - 0.49 427 ASTM A193 Gr.B16 0.36 - 0.44 566 NUTS ASTM A194 Gr.2H 0.4 Min. 427 ASTM A194 Gr.7 0.37 - 0.49 566 PLATES ASTM A515 Gr.60 0.30 Max. 450 ASTM A516 Gr.60 0.30 Max. -46 to 300 ASTM A387 Gr.11 Cl.1 0.10 -0.20 570 ASTM A387 Gr.22 Cl.1 0.15 Max. 600 ASTM A240 Gr.304 0.08 Max. -200 to 500 ASTM A240 Gr.304L 0.035 Max. -200 to 500
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ANNEXURE - C
VALVE DATA SHEETS
SL. SYSTEM SIZE TYPE OF END ANSI MATERIAL NO. VALVES CONNECITON RATING OF HOUSING 1 LP EXTRACTION Above 50 NB Gate Valve BW 150# A216 Gr.WCB STEAM Check Valve BW 150# A216 Gr.WCB 50 NB & Below Gate Valve SW 800# A105 Globe Valve SW 800# A105 2 IP EXTRACTION Above 50 NB Gate Valve BW 300# A216 Gr.WCB STEAM Check Valve BW 300# A216 Gr.WCB 50 NB & Below Gate Valve SW 800# A105 Globe Valve SW 800# A105 3 HP
EXTRACTION Above 50 NB Gate Valve BW 600# A216 Gr.WCB
STEAM Check Valve BW 600# A216 Gr.WCB 50 NB & Below Gate Valve SW 800# A105 Globe Valve SW 800# A105 4 BFP SUCTION Above 50 NB Gate Valve BW 150# A216 Gr.WCB 50 NB & Below Globe Valve SW 800# A105 5 BFP DISCHARGE Above 50 NB Gate Valve BW 900# A216 Gr.WCB Check Valve BW 900# A216 Gr.WCB 50 NB & Below Globe Valve SW 1500# A105 6 CONDENSATE Above 50 NB Gate Valve BW 150# A216 Gr.WCB WATER Check Valve BW 150# A216 Gr.WCB Globe Valve BW 150# A216 Gr.WCB 50 NB & Below Gate Valve SW 800# A105 Globe Valve SW 800# A105 7 LP HEATER
DRAIN Above 50 NB Gate Valve BW 150# A216 Gr.WCB
Globe Valve BW 150# A216 Gr.WCB 50 NB & Below Gate Valve SW 800# A105 Globe Valve SW 800# A105
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VALVE DATA SHEETS
SL. SYSTEM SIZE TYPE OF END ANSI MATERIAL NO. VALVES CONNECITON RATING OF HOUSING 8 HP HEATER
DRAIN Above 50 NB Gate Valve BW 300# A216 Gr.WCB
Globe Valve BW 300# A216 Gr.WCB 50 NB &
Below Gate Valve SW 800# A105
Globe Valve SW 800# A105 9 COOLING
WATER Above 50 NB Butterfly
Valve FL 150# A216 Gr.WCB
50 NB & Below
Globe Valve FL 800# A105
10 DEMINERALISED
WATER Above 50 NB Diaphragm
Valve FL 150# A351 Gr.CF8
50 NB & Below
Globe Valve SW 150# A182 Gr.F304
11 CHEMICAL
DOSING
Below 50 NB Ball valve SW 150# Polyethylene
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ANNEXURE - D
SCHEDULE OF THICKNESS FOR THERMAL INSULATION
TEMP. Up to 101 151 201 251 301 351 401 451 501 °C 100 to to to to to to to to to 150 200 250 300 350 400 450 500 550 Pipe Dia Insulation Thickness (mm) 15 mm (1/2”) 25 25 25 35 45 50 60 70 85 95 20 mm (3/4”) 25 25 30 35 45 55 65 75 90 100 25 mm (1”) 25 25 30 40 45 60 70 80 90 105 32 mm (1 ¼”) 25 25 30 40 50 60 70 85 95 110 40 mm (1 ½”) 25 25 30 40 50 60 75 85 100 115 50 mm (2”) 25 25 30 45 55 65 80 90 105 120 65 mm (2 ½”) 25 25 35 45 55 70 80 95 110 125 80 mm (3”) 25 25 35 45 60 70 85 100 115 130 100 mm (4”) 25 25 35 50 60 75 90 105 120 140 125 mm (5”) 25 25 35 50 65 75 90 110 125 145 150 mm (6”) 25 25 35 50 65 80 95 115 130 150 200 mm (8”) 25 25 40 50 65 85 100 120 140 160 250 mm (10”) 25 25 40 55 70 85 105 125 145 165 300 mm (12”) 25 25 40 55 70 90 105 125 150 170 350 mm (14”) 25 25 40 55 70 90 110 130 150 175 400 mm (16”) 25 25 40 55 75 90 110 130 155 180 450 mm (18") 25 25 40 55 75 90 110 135 155 180 500 mm (20") 25 25 40 55 75 95 115 135 160 185 550 mm (22") 25 25 40 55 75 95 115 135 160 185 600 mm (24”) 25 25 40 55 75 95 115 140 165 190
ANNEXURE - E
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DESIGN PROCEDURES FOR PIPE SUPPORTS
• The design loads for hangers & supports shall include the weight of pipe, the weight of
insulation and the weight of medium transported or the medium used for testing, whichever is heavier. All components of hanger or support assembly shall be designed for the above design load and the self-weight of hanger/support assembly.
• Design and manufacture of hanger components including springs shall generally confirm
to MSS - SP58, MSS-SP69 and MSS-SP89. • The materials used in the construction of hangers, supports and accessories shall be the
most suitable for the service intended. • Material of lugs and welded attachment to pipes and pipe clamps shall be compatible
with parent pipe. However, welded pipe attachments shall be minimised. • The hangers shall be provided with suitable linkages to permit swing. The angle of
inclination shall not exceed 4° from the vertical plane. • The diameter of hanger rods for piping, 50mm NPS and smaller, shall not be less than
10mm. • Bolted pipe clamps, used with rod hangers, for pipe 50 mm NPS and smaller, shall have
a minimum thickness of 6mm. • Springs, for spring hangers, shall be of helical compression type and shall be provided
with means to prevent misalignment, buckling and eccentric loading and with stops to prevent excessive travel.
• Where variable spring hangers are specified, the units selected shall have support
variation of not more than 25% through its total travel range. • Constant spring hangers shall be specified where pipe thermal vertical movements
exceed 40 mm. • Constant support hangers shall have a field load adjustment range of +10% of the
operating load specified. The total travel of the unit selected shall be the calculated travel of plus 20% to take care of possible discrepancies. Constant support hangers shall have support variation of not more than 6% throughout the total travel range.
• All rigid / spring hangers shall provide a means of vertical adjustment after erection.
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• The threads on threaded parts such as hanger rods, nuts and turnbuckles shall conform to applicable codes for the coarse-thread series with a “medium” class fit or equivalent.
• All anchors shall be designed for rigid fastening to the structure either directly or through
a bracket. Anchors and guides shall be capable of withstanding the moments and forces imposed by thermal expansion.
• Pipe supports shall be designed such that a minimum amount of heat will be transferred
to the structure. • Stainless steel shim plates are required between stainless steel pipe and carbon steel
supports. • The maximum allowable deflection of supports due to the design loads in the direction of
the restraints shall be 3mm. • Shear lugs shall be provided for friction type clamped support on riser pipes. Friction
type clamped supports shall not be normally used on a vertical riser for critical systems. • The hanger shall be offset 1/2 of the thermal movement in cold position if swing angle of
the rod is in excess of 5 degrees, but not exceeding 10 degrees. • Suitable locking devices shall be used at all threaded connections of the hanger
assembly. • Each half assembly of a riser support shall be capable of supporting the entire load. • Overall rod length shall not be greater than 6m without proper evaluation.
Rigid Restraints: • Restraints fabricated out of structural steel shall have a clearance of 1.5mm in direction
of the restrained movement except in the downward direction. • Anchors shall only be used where full constraint of piping against three deflections and
three rotations are required. • Dependence on friction straps or bolted joints shall be avoided, to the extent possible,
especially in pipes, where design temperature exceeds 120°.
ANNEXURE - F
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STRESS ANALYSIS DESIGN CRITERIA
∗ General: This criteria is established for piping flexibility analysis to be performed during piping
design work for the plant. ∗ Application code & Specification : Stress analysis of piping systems shall be performed in compliance with ANSI B31.1 ∗ Temperature : Installation temperature = 30° C Design temperature : Design temperature is the most severe sustained fluid
temperature subject to conditions of section 3.1 above. ∗ Computer Software : The computer pipe stress analysis shall be carried out using CAESAR - II ver. 3.24
computer software. ∗ Basis for computer pipe stress analysis : Detail pipe stress analysis shall be required for the following :
Pipe Diameter Design Temperature (mm) (in) Carbon steel (deg. C)
& Ferritic alloys Austenitic Steel
(deg. C) 80 3 > 440 > 390
100 4 > 300 > 260 150 6 > 260 > 200 200 8 > 230 > 160 250 10 > 190 > 130 300 12 > 160 > 120 350 14 > 140 > 100 400 16 > 130 > 90 450 18 > 120 > 80
500 & above 20 > 100 > 80
• All following piping connected to reciprocating / rotary equipments. (i) Pipe diameters of 80mm to 200mm with design temp. greater than 60° (ii) Pipe diameter 250 mm & larger
• Steam lines connected to turbine. • Feed water pump suction and discharge lines.
ANNEXURE - G
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MAJOR REQUIREMENTS OF IBR
Vessels (Reg. 2 (c) of IBR): Any closed vessel exceeding 22.75 litres (five gallons) in capacity, which is used
exclusively for generating steam under pressure and include any mounting or other fittings attached to such vessels, which is wholly or partly under pressure when steam is shut off.
Piping: Steam Pipe (Reg. 2 (k) of IBR): Any pipe through which steam passes if 1. Steam pressure exceeds 3.5 kg/cm2 above atmosphere, OR 2. Pipe size exceeds 254 mm internal dia.
Note: Following are not under IBR - Steam Tracing - Heating coils or - Tubes of Tanks, heat exchangers Feed Pipe (Reg. 2 (k) of IBR): Any pipe or connected fitting wholly or partly under pressure through which feed-
water passes directly to a boiler. Material Certificates: 1. Any item part of steam piping i.e. pipes, valves, fittings, traps, safety valves must
have material certificates, countersigned by the local boiler inspector. 2. For imported items - certificates issued by an authority empowered by the Central
Boilers Board (as listed in the Appendix C of IBR) or under the Law in force in a foreign country in respect of boilers manufactured in that country may be accepted.
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Drawings: 1. Prior to fabrication of any items i.e. Boiler, fabricated pipe work which are
coming under the purview of the boiler drawings shall be submitted before construction to the Chief Boiler Inspector of the State where the plants / equipment / Pipe line will be installed.
2. The Chief Inspector shall after examination of the drawings and particulars shall
inform the proposers whether he is satisfied with the design and fitness of the parts for the intended pressure and if not, what modification is necessary therein with respect to design, material etc.
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ANNEXURE - H
ACCESSIBILITY REQUIREMENTS FOR VALVES & INSTRUMENTS Valves, Instrument, Equipment to be operated
Centreline of item to be operated, located less than 3.6m above grade, 2.75m above floor or platform or 1.8m above wing platform
Centreline of item to be operated, located more than 3.6m above grade, 2.75m above floor or platform or 1.8m above wing platform
Exchanger heads Nil Platform Operating valves 2” &
llFixed ladder Fixed ladder
Operating valves 3” & above Platform Platform Motor operated valve Platform Platform Control valves Platform Platform Relief valves 2” & smaller Fixed ladder Fixed Ladder Relief valves 3” & above Platform Platform Block valves 2” & smaller Portable ladder Portable ladder Block valve 3” & above Platform (Note-1) Platform (Note-1) Battery limit valves Platform Platform Pressure instrument Fixed ladder if above 2.2m
h i hFixed ladder
Temperature instrument Fixed ladder if above 2.2m h i h
Fixed ladder Sample points Platform Platform Gauge glasses Fixed ladder Fixed ladder Level controllers Platform Platform Man ways / Manholes Platform Platform Hand holes / Inspection h l
Platform Platform Nozzles No access reqd. (Note-2) No access reqd. Vessel vents Portable ladder Fixed ladder Line drains & vents Portable ladder Portable ladder Orifice flanges Portable ladder Portable ladder Note: 1) Center line of Block valves located above 2.0 meter from the operating floor
which are required for normal operation shall be provided with portable platform or chain for operation of valves.
2) Temporary arrangement for access should be feasible.
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ANNEXURE - I
RECOMMENDED VELOCITY RANGE FOR VARIOUS FLUIDS A. STEAM
Pipe Size
Average velocity in meter/second
Below 50 NB
50 to 100 NB 100 NB & up
1.Saturated steam up to 7.0 kg/cm2 (g)
15-20 20-35 25-45
2.Saturated steam over 7.0 kg/cm2 (g)
15-25 20-35 30-50
3.Superheated steam up to 7.0 kg/cm2(g)
20-30 25-40 30-50
4.Superheated steam from 7.1 to 3.5 kg/cm2 (g)
20-35 30-45 35-55
5 Superheated steam from 35.1 to 70 kg/cm2 (g)
20-35 30-50 40-60
6. Superheated steam from 70 kg/cm2 (g)
20-35 30-50 45-70
7.Turbine by pass steam
200 For all Line sizes
8.Exhaust steamline from the line to atmosphere
20 For all Line sizes
9.Vacuum lines
60 For all Line sizes
A Issued for Approval
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B. Water
Average Velocity
Meter / second
Firewater lines 0.6. to 0.9
Feed water suction lines 1.0 to 2.5
Feed water discharge lines 2.5 to 5.0
Auxiliary cooling water (suction) 0.6 to 1.5
Auxiliary cooling water (discharge) 0.9 to 2.5
Condensate delivery lines 0.9 to 2.2
Condensate suction lines 0.4 to 0.7
Main cooling water lines (discharge) 0.9 to 2.5
Main cooling water lines (suction) 0.6 to 1.2
Viscous fuel oil 0.6 to 0.9
Gases 25 to 30
C. Oil and gas lines
Average Velocity
Meter/second
Lubricating oil and fuel oil suction
Lines (depending on viscosity) 0.5
Fuel oil supply lines (pre-heated) 3.0