PIPING GUIDE

1) WHAT IS WPS ?

ITS AN ABBREVIATION FOR WELDING PROCEDURE SPECIFICATION IS A SPECIFICATION FOR ALL THE PIPING MATERIALS AND FILLER MATERIAL WHICH WILL BE USED IN A PLANT TO ASME CODE AND ANSI B31.

2) ANSI CODE :

a) POWER PLANT PIPING - B31.1b) CHEMICAL PLANT PIPING - B31.3

3) FOUR TYPES OF GASKET :

a) ASBESTOS GASKETb) RING GASKET ( RING, OCTAGONAL, OVAL )c) SPIRAL WOUND ( METAL )d) TITANIUM GASKET

4) E – 7016 is a type of welding rod. What does under lined number indicate ?

Tensile strength is – 70 ksi (70,000 psi )5) What is FF elevation ?

Elevation of pipe flange face which is connected to equipment nozzle.

6) Five Types of Non Destructive Examination :a) Liquid Penentrant Testb) Magnetic Particle Testc) Radiographic Testd) Ultrosonic Teste) Visual Test

7) Three Types of Destructive Examination :a) Impact Testb) Bend Testc) Tensile Test

8) What is Expansion Joint ?Joint that is fabricated to allow lines expansion or contraction due to fluids temp. change.

9) What is JIS equivalent of ASTM A53 Gr B :

STPG 42

10) what is punch list ?

List of unfinished work or unmatched item according to DRWG and spec. before Hydrotest.

11) Explain color coding ?

Marking of piping bulk materials to identify the Material.

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12) What is Steam Trap ?

Trap Water which is Formed when the steam is condensate.

13) What is the use of Lateral :

Limit fluids Resistance and minimize choak of pipe due to foreign material.

14) What does holiday detector detect :

Pin holes in Coating and Wrapping.

15) What is the role of Venturi ?

Fluid amount check.

16) What is the Reason for installing a loop in piping ?

To ease Expansion and contraction of pipe due to fluid temp. change.

17) What is cathodic protection ?

Way of protecting metal against corrosion by passing a small electric current between the metal surface and the surrounding ground or water.

18) What is the break flange ?

For Maintenance of Vertical pump, Exchanger, Drums and other equipment.

19) What is the Insulation Kit ?

To Isolate between Above ground and Under ground.

20) Type of Supports :

Spring support, Hanger support, Dummy support, Shoe, Anchor, Guide and Pick up.

21) Welding Rods to be used according to AWS code :

a) A312 TP 316L – GTAW ER 316L SMAW – E316Lb) A312 TP321 - GTAW ER 347 SMAW – E347c) A335 P22 - GTAW ER 90S – B3 SMAW - E9016 B3

22) What Backing gas should be used when welding stainless steel or Alloy steel and what shall be the purity of this Gas ?

Argon – 99.9 %.

23) Control valve : - Is usually choosen to be smaller than line size to avoid throttling and consequent rapid wear of the Seat.

24) Design of any processing plant is usually accomplished in three phases :

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a) Conceptual Design – are made when sketchy or minimal information is used to prepare an abstract arrangement of a plot plan or an equipment and piping layout.

b) Preliminary or study phase – design are made with unchecked or uncertified data to design a facility in sufficient detail so that the document produced can be used for detail design.

c) Detail phase – All design are finalized, the design used such checked data as steel and concrete, drawings, hydraulic and certified vendors drawings for equipment valves and instruments.

25) Open system : Is one in which the content of a line are discharged and not recovered.

26) Closed system : Is one which the contents of relief system or steam trap condensates are recovered.

27) Steam Turbine : Are used where there is a readily available source of steam and are also used to drive stand by process pumps in critical service in the event of an electrical

power failure and emergency standby equipment such as fire water pumps and electrical generators.

28) Turbine : Is a machine for deriving mechanical power (rotating shaft ) from the expansion of a gas or vapor (usually air or steam in industrial

plants).

29) NPSH : Net Positive Suction Head.

30) Diaphragm : These forms of diaphragm valve are popular for regulating the flow of slurries and corrosive fluids and for vacuum.

31) Safety relief valve : Relieves excess pressure of either gas or liquid which may suddenly develop a vapor phase due to rapid and uncontrolled heating from chemical reaction in liquid laden vessel.

32) Butterfly valve : Used for liquid, slurries, powders and vacuum. The usual resilient plastic seat has a temperature limitation but tight closure at high temperature.

33) Check valve : Designed to permit flow of liquid or gas in a one direction and close if flow reverses.

34) Gate valve : Use for water , gas, steam, slurries line suitable for throttling and full flow use.

35) Globe valve : Use for regulating flow should be from seat stem side, assist closure and to prevent the disc chattering against the seat in the throttling position.

36) Carbon steel : Lose strength at high temperature, electric resistance welder (ERW) pipe is not considered satisfactory for service about 750*F and furnace butt welded (FBW) pipe above about 650*F.

37) Steam Tracing : To prevent fluid from congealing, forming hydrates, condensing, interfering with operation or causing any damage to piping, equipment and instrument.

38) Expansion Joint : To accommodate movement in piping due to temperature changes and

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also used to absorb vibration.

39) Control Station : Is an arrangement of piping in which a control valve is used to reduced and regulate the pressure or rate of flow of steam, gas or liquid.

40) In Horizontal runs: The taps are located at the tops of the flanges in gas, steam and vapors lines, an approximately horizontal position avoids vapors locks in liquid lines.

41) Vents: Are needed to let gas usually air in and out of service. Basically remove the air pocket from the line.

42) Break Flange : Piping connected to channel head nozzle should be furnished with break flange to facilitate the removal of the channel head.

43) Separators : Used to collect droplets from a gaseous stream. ( Ex : To collects oil droplets from a compressed air, or condensates droplets from wet steam.

44) Temporary strainers: Used for start – up operations on the suction side of pumps and compressors, after start – up the screen usually is removed.

45) Thermal Stresses: Changes in temperature of piping due either to change in temperature of the environment or of the conveyed fluid cause changes in length of the piping.

46) Steam Traps: The purpose of fitting traps is to obtain fast heating of system and equipment by freeing the steam lines of condensates and air.

47) Heater: Heats a process stream by condensing steam.

48) Condenser: Condenses vapors by Transferring heat to cooling water, atmospheric air or other media.

49) Chiller: Cools a process stream to very low temperature by evaporating a refrigerant.

50) Two kinds of steam turbine: a) Back pressure Turbine : Are driven by high pressure steam and do not require surface condenser. b) Condensing Turbine : Are usually driven by low pressure steam. 51) Gas Turbines: Are used in various application including gas transmission gas lift, liquid pumping , gas re injection and process compressor.

52) Inter coolers: Are primarily used to reduce the operating temperature with in a compressor circuit which allows the use a smaller machine with fewer cylinders.

53) Compressor Machine: Are used to increase the pressure of a gas by mechanically reducing its volume with in its case.

54) Condensate pump: The condensate pump is usually vertical removes the condensates from the hot well in the surface condense. Condensates form during liquification in the condenser and is collected in the hotwell.

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55) Drums: Collects liquids from vapors circuits and pump it to other process groups, disposal or product storage. Used in process plant as intermediate containers that received liquid from distillation and condensing equipment.

56) Coolers : Cools a process stream by transferring heat to cooling water, atmosphere and other media.

57) Heat Exchanger : The principal application of a heat exchanger is to maintain a heat balance through the addition or removal source or between stream of two different operating temperature.

58) Reactor : Are used in processing facilities to contain catalyst that promote chemical reaction of feeds. Reactor are generally vertical steel hallow vessels and often operate under very high temperature and pressure.

59) Tower : Are cylindrical steel vessel that are used for distillation of materials in the production of such products as gasoline, diesel and heating oil.

60) Non- Destructive : Knowing the internal defect of weld without changing the appearance of the material.

61) Inconel : A High Nickel Alloy containing chromium and Iron, resistant to Oxidation and Corrosion.

62) Knock out Drum : A stream of gas containing drops of liquid is passed through a knock out drum in order to slow down the flow and allow the liquid to separate and collect.

63) Pump Suction : Eccentric reducers are used in lines 2 ½” and larger and arranged to avoid creating a vapor space and creating a pocket which would need to be drained.

64) Valves are used for these purposes : a) process control during operation.b) Controlling services and utilities, steam, water, and air, gas, and

Oil.c) isolating equipment or instruments for maintenance.d) Discharging gas, vapor and liquid.e) Draining piping and equipment – on shutdown.

f) Emergency shutdown in the event of plant mishap or fire.

65) Venturi meter : Instrument for measuring of gas or liquid measuring the decreased pressure so caused.

66) Slip on flange : Has poor resistance to shock and vibration easier to align than the welding neck flange, calculated strength under internal pressure are about one third that of the corresponding the weld neck flange.

67) Weld Neck Flange : Suitable where extreme temperature shear impact and vibratory stresses apply primarily use for vessel and equipment nozzle.

68) Support types are defined as follows : a) Anchor – a support fixing the piping completely.

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b) Guide – a support restricting the movement perpendicular to pipe axis, but the axial movement is allowed.

c) Hanger – a support hanging the piping.d) Spring – a resilient support which allows vertical movement.e) Resting support – a simple support bearing the pipe weight only.f) Directional stop – a support restricting the movement of a certain

direction.g) 3 – way restraint- a support restricting the movements of three

directions, but permitting the rotation.h) Pick up support : a support resting small diameter pipe using large

diameter pipe instead of steel structure.

69) Seal Welds : may be used only to prevent leakage of threaded joints and not to be considered as contributing any strength to the joints.

70) Threaded joints checklist : a) What is the maximum diameter piping allowed in hazardous service ? ( 1.1/2” ) b) What is the minimum sized piping that can be installed on pipe racks ?

( 1” ) 71) How many threads can be visible after seal welding threaded joints ? Zero. Seal welding must cover all threads.

72) What is the gap requirement for socket welds for new construction? 1.5 mm to 3.0 mm gap prior to welding.

73) What is the best way to assure consistent gap is maintained? Use of gap –o- let rings.

74) What is the minimum fillet weld size for a socket welded connection? 1-1/4t but not less than 3.2 mm.

75) What are common failures in the quality system during fit up that leads to hydro test failures? Failure to properly clean, de burr and degrease fittings and piping prior to welding. Oil residue from cutting causes through weld porosity and leakage during hydro tests.

76) Welded branch connections ( check lists ) : a) Follow spec. branch connection tables and standard drawings to determine

required construction.b) Have the tell- tale holes for air testing been drilled, tapped, de burred and oil

removed by cleaning ( sand blasting ).c) Has the branch to header weld been welded flush. NDT performed, accepted prior

to fit up of reinforcement pad.d) Has the repad been properly cold worked and radiused to meet the piping OD and

assure good fit up. No hammer marks.e) Do not allow flange tack welding above the branch connection until the repad fit is

acceptable. Maximum gap is 1.6 mm.f) A 6 mm gap maximum is allowed between repad and branch for root opening.g) Follow preheat tables and W – 011 requirements for GTAW & SMAW process on

welding. 77) Supports – Check lists :

a) What critical over looked requirement on support installation causes the most

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Rework ?

Fit up, elevation and slope per AFC drawings, this checked by survey or level( string line ) in accordance with PIPS and procedures.

b) What is an expansion loop?

Expansion loop is the piping arrangement, which allows the movement of the pipeDuring operation with high temperature and pressure and during the shut down , piping will come down to cool condition. During the both period, with the help of Expansion Loop, the pipes are Expand / contract accordingly.

78) What is a guide? It will control the horizontal movements of the pipe.

79) When should shims be installed? To correct movement and correct misalignment and provide full bearing of support as needed.

80) Give Examples of unique support details that allow piping freedom of movement for thermal expansion : a) Teflon slides, wear pads, spring hangers, hydraulic snubbers, Expansion joints.

81) Clearances :a) 50 mm rule between all piping and supports.b) 24” clearance from supports, dead legs, drain and vents.c) 300 mm from grade @ all piping.d) Fittings, butt welds, etc, adjacent to hangers, clamps, supports, etc must be

spaced to allow freedom of piping movement. Alternatively, flush grind and NDT can be allowed as long as weld location will not restrict piping movement.

82) Serrated Finish : Is used with asbestos and other gaskets. The regular smooth finish is used with gaskets made from hard materials and with spiral wound gaskets. Cold water finish is normally used without gaskets.

83) Gaskets : Are used to make a fluid resistant seal between two surfaces.

84) Choice of gasket is decided by : a) Temperature, pressure and corrosive nature of the conveyed fluid.b) Whether maintenance or operation requires repeated uncoupling.c) Code requirements that may apply.d) Cost.

85) Drip legs : Often made from pipe and fittings, the drip leg is an inexpensive means of collecting condensate. Removal of condensates from steam lines.

86) Hanger Support : Device which suspends piping ( usually a single line ) from structural steel, or steel and concrete. Hanger are usually adjustable for height.

87) Saddle : a welded attachment for pipe requiring insulation and subject to longitudinal or rolling movement ( resulting from temperature changes )

88) Piping and Instrument diagram : This drawing is commonly referred to as the P & ID. Its object is to indicate all process and service lines, instrument and controls, equipment, and data necessary for the design group. The process flow diagram is the

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primary source of information for developing the P&ID’S.

89) Dry Steam : Is a gas , consisting of water vapor only. Placed in contact with water at the same temperature, dry steam will not condense, nor will more steam form – liquid and vapor are in equilibrium.

90) Wet Steam : Consists of water vapor and suspended water particles at the same temperature as the vapor. Heating ability ( quality ) varies with the percentage of dry steam in the mixture ( the water particles contain to latent heat of vaporization ) Like dry steam, Wet steam is in equilibrium with water at the same temperature.

91) Super heated steam : If heat is added to a quantity of dry steam, the temperature of the steam will rise and the number of degrees rise in temperature is the degrees of super heat. Thus Super heat is sensible heat – that is it can be measured by a thermometer.

92) Condensate : What it is & How it forms : Steam in a line will give up heat to the piping and surroundings, and will Gradually become wetter, its temperature remaining the same. The change of state of part of the vapor to liquid gives heat to the piping without lowering the temperature in the line. The water that forms is termed ‘condensate’ of the line initially contains super heated steam, heat loss to the piping and surroundings will first cause the steam to lose sensible heat until the steam temperature drops to that of dry steam at the line pressure.

93) Steam Traps : Are designed to react to changes in temperature, pressure or density. Temperature sensitive ( or Thermostatic ) traps – are of two types : The first Type operates by the movement of a liquid filled bellows, and the second uses a bimetal element. Both types are open when cold and readily discharge air and condensate at start up. As these traps are actuated by temperature differential, they are economic at steam pressure greater than 6 PSIG.

Impulse traps: are also refered to as ‘thermo dynamic’ and controlled disc. These traps are most suitable to applications where the pressure down stream of The trap is less than half the up stream pressure. Water hammer does not affect Operation. They suitable for steam pressure over 8 PSIG.

Density Sensitive Traps are made in float and bucket designs. The float trap is able to discharge air unless fitted with a temperature sensitive vent ( the temperature limitation of the vent should be checked ).

Floats traps some times may fail from severe water hammer.

Inverted bucket trap is probably the most used type. The trap is open when cold, but will not discharge large quantities of air at start – up unless the bucket is fitted with a temperature sensitive vent. The action in discharging condensate is rapid Inverted bucket traps will operate at pressure down to ¼ psig.

94) what are the common type of valves and its function? Gate Valve – on / off service Globe valve – throttling service Check valve – non return valve

95) Where will you place the level gauge of a kettle type re boiler?

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After the weir.

96) What is insulated flange? A flange said that is electrically insulated, composed of insulating gasket, Washer and sleeve.

97) An Inspection & Test Plan? A mandatory item in the quality plan that guides and assures quality in a Specific type of work in basic sequence of QC activity steps. 98) A Quality Control Procedure? A document that details the specific steps needed to fulfill the QC activity in the ITP.

99) Quality control form? A written documentation detailing a specific activity in the ITP & QC procedure

100) What is a specification ? A specification is a guide line to assure that minimum Quality standards are met.

101) What types of inspection action points are found in the ITP? Hold, Witness, Surveillance, Review.

102) What is the differences between the 4 types of inspection points? Detail answer and ensure a clear under standing by candidate.

103) What is a P& ID? Piping and instrument diagram will show the piping layout and detailed notes relating to piping and instrumentation.

104) What is SIS? Safety Instruction Sheet that gives full design details related to a piping system or Line.

105) What is a piping system? Describes the specific service or fluid.

106) What is the piping line class designation? A specific name in alphanumeric designation describes features of a piping system.

107) Show example of a line designation from isometric drawing? ICS1P3 = 150# class, Carbon Steel, 1/16” CA, General hydro carbon.

108) What is an isometric drawing? A detailed piping system / line drawing with reference to construction and material Requirements

109) What things are found in a piping isometric drawing? Line conditions, references to drawings, materials of construction, elevations, Orientation, piping and drawing details and notes, revision control and approval Status.

110) What is a Material list or Material Take off Sheet ( MTO )? Details of materials used in construction of piping, using with isometrics.

111) What is a PIP? Process Industry Practice details requirements for fabrication an Industry Practice.

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These are often the basis for SA standards.

112) Material Inspection :a) How do you verify the material? and mention several items to check.

Mill Certificate, heat number, color coding and PMI, schedule, rating, Carbon equivalentValue for PREHEAT, diameter, class, grade.

b) How do you identify fitting and flanges?Correct ratings, sizes, class, schedules as marked on fittings & mill certificates.

c) How do you check piping for the correct schedule?Use a Vernier Caliper and ensure piping is within tolerances.

d) What are the tolerances for physical piping straightness and defects?Check the ASTM or API piping specification.

e) What is standard mill tolerance for piping?87 ½ % ( all ) to 115% ( greater than 2” ), 120% ( 2” & less ) of nominal

f) How to check Valves of the correct rating and material.CMTRs & trim during Valve testing ( Visual inspection )

113) Name the different types of mating flanges? RFWNF, RFSO, RTJ and FF.

114) What kind of the inspection required during Gasket installation? Check the Gasket material as per the drawing and specification, size, rating and visual Inspection of surface damages.

115) What is the difference between torqueing of CS and SS bolting? Yield strength is greater in Carbon and torque values are greater.

116) Explain ‘Spectacle’ plate : Used for Service and shutdown ( isolation ) for maintenance purposes.

117) What is Jack Screws and when are they required? They are located at flanged connections to facilitate maintenance and removal of flange and Orifice plates to facilitate maintenance.

118) What item to be checked during orifice flange fabrication? Flush Grinding of butt welds of the orifice flange inside and seal welding of orifice tapping Pipes.

119) What are the NDT methods are required during orifice flange installations? Visual and PT / MT.

120) What is cold spring? Application of Mechanical Stress ( bending, twisting, pulling ) upon a piping segment to Achieve bolting and on to another segment.

121) Is cold spring acceptable? No.

122) Flange connects to a pump or other equipment, is there any physical tolerance involved? Yes, Manufacturer tolerance.

123) Check list for Reinstatement :

# Check that correct bolts and gaskets are installed at all reinstated joints completed and Recorded.

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# Check that all process blinds and spades have been correctly installed as indicated on the P& ID.

# Check that spectacle blinds are in the correct position.

# Check that correct valves have been installed in the correct ‘Flow’ position.

# Check that specified block valves have locking devices correctly installed.

# Check that all valves are functioning properly and that spindle has been coated with copa-slip are equal there specified.

# Check that relief valve have been correctly installed.

# Check that all pump suction strainers have been correctly installed.

# check that correct flow through filters, and strainers, traps, check valves and globe valves.

# Release for final equipment alignment.

# Hydro test completed.

124) HYDRO TEST PACKAGE REVIEW :1) P&ID for correct revision.2) Isometric Drawing for correct revision.3) Isometric Drawing confirm to P&ID.4) Boundaries of hydro test, filling / draining / vent point and ensure all

necessary P&ID ‘s / Isometric are in the package.5) Ensure all line listed in test package are identified and test pressure is

correct as per LDT.6) Check blind lists of sizes, thickness and rating.7) Check exception list.

125) THE CONTENTS OF TEST PACKAGES ARE : 1) Marked up P&ID and isometric drawings showing the location and type of pipe supports, the boundaries of the test, valve position and the location of vents, drains, temporary blinds ( size and thickness ), the water fill point and pressure gauges. 2) The test medium and pressure.

3) A piping line list.

126) SOME APPLICABLE LINE CHECK PUNCH : Check point: Description : 1) Completion of Welding Inspection Report Inspection class,NDE,PWHT,WPS2) Appearance of welds Crack, under cut, overlap, arc strike, fillet size etc.3) Distance Between weld Closeness4) Orifice flange, Orifice run, Nozzle orientation. Orientation of tapping, smoothness of inside surface.5) Position of welding earth No structure and temporary support.6) Deformation of material. Dent, deforming by construction work.

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7) Weep hole. On pad, support, PSV vent.8) Branch and Nozzle Orientation , location.9) Verticality, Horizontality and slope. As per isometric drawing.10) Piping connection to Equipment nozzle. Any extra force or movement is prohibited. 11) Support and shoe. Type, location, removal, clearance12) Gasket. Type, material, size, gasket no.13) Valve. Type, material, size, flow direction.14) Bolt & nuts. Type, material, size, length, tightness15) Blank plate. Type, material, size, blind no.16) Jack screw. Type, material, size.17) Drain and vent. Location, size, orientation.18) Piping line class break. Material, location, rating class as shown in P&ID. TABLE FOR GASKET :

GASKET MATERIAL EXAMPLE USE MAX. TEMP. DEG.FSynthetic rubbers Water, Air 250Vegetables Fiber Oil 250Solid Teflon Chemicals 500Compressed Asbestos Most 750Carbon Steel High Pressure Fluid 750Stainless Steel HP.Fluid / Corrosive 1200Spiral Wound Chemicalsa) Teflon Most 750b) Cs / Asbestos Corrosive 1200c) SS / Asbestos Chemicals 500d) SS / Ceramics Hot Gases 1900

PIPE SIZE MAX. SPAN ( M ) DEFLECTION ( MM )

12” 12 38” 11 36” 10 3.34” 8.6 3.33” 8 4.32” 6.7 4.6

1-1/2” 5.4 4.61” 4.5 4.8¾” 4.5 4.6½” 4 4.3

NOTE : This is calculated as following condition. ASTM A 53 SCH. 40. Full water, continuous beam.

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Table – 1Guide for selection of Welding Electrodes and Filler Metal Rods.Base metal ( ASTM / ASME )Product Forms

Welding Metal ( AWS )

PLATE PIPE FORGING

TUBE CASTING ELECTRODE( SMAW )

FILLER METAL( GTAW )

CARBON STEELA516 GR. 70A515 GR. 70

A285 GR. B

A106 GR.BAPI 5L – BA53 GR.B

A105 A179 A216- WCB E - 7018 ER – 70S-2

LOW ALLOY STEELA387 GR.1 A335 – P1 A182-F1 A213-T1 A217-WC1 E-7018-A1 ER-80S-GA387 GR.12 A335 – P12 A182-F12 A213-T12 A217-WC4 E-8018-B2 ER-80S-B2A387 GR.11 A335 – P11 A182-F11 A213-T11 A217-WC6 E-8018-B2 ER-80S-B2A387 GR.22 A335 – P22 A182-F22 A213-T22 A217-WC9 E-9018-B3 ER-90S-B3

STAINLESS STEELA240-304L A312-

TP304LA182-F304L

A213-TP304L

A351-CF3 E 308L-16 ER-308L

A240-316L A312-TP316L

A182-316L

A213-TP316L

A351-CF3M E 316L-16 ER-316L

904 L A790 A789 FOX CN 20 / 25M

SAF 2205 A790 A789 E2209-17 ER-2209SPECIALITY ALLOYS

316L U.G. 316L U.G. 316L U.G. 316L U.G. - Thermanit 19 / 15H

310MoL 310MoL 310MoL 310MoL E310LMo Thermanit 25 / 22H

Alloy 20 Inconel 112 Inconel 625Incoloy 800HT

Incoloy 800HT

Incoloy 800HT

Inconel 117 Inconel 617

HK-40 HK-40 E310 H ER-310H25-35-CbMod.

25-35-CbMod.

Inconel 117 Inconel 617

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SPECIFICATIONS FOR CARBON STEEL SYSTEMSL.NO. COMMODITY B31.3

1 Pipe ASTM A53 / API 5L2 Pipe – Low Temperature ASTM A333 Gr63 Pipe – High Temperature ASTM A1064 Bolting ASTM A193 B7 / ASTM A3205 Nut ASTM A194 2H6 Fittings ASTM A234 WPB7 Fittings – Low Temperature ASTM A420 WPL68 Fittings – High Temperature ASTM A234 WPB

ASTM A216 WCB9 Valves ASTM A105 / API 60010 Valves – Low Temperature ASTM A350 LF2 / ASTM A352 LCB11 Valves – High Temperature ASTM A216 WCB12 Flanges ASTM A105/ ASTM A181/ ASME B16.513 Flanges – Low Temperature ASTM A350 LF2 / ASTM A352 LCB14 Flanges – High Temperature ASTM A105/ ASTM A181/ ASTM A216 WCB

THE CHECK LIST FOR PIPING WORK COMPLETION NEEDS TO BE CONFIRMED BEFORE THE PRESSURE TEST CAN COMMENCE :CHECK LIST IS AS FOLLOWS :

1) Piping should be Correct Dimension, Location and Orientation.2) Welding Completed.3) NDE Completed.4) PWHT and Hardness Test Completed.5) Valve, in line item and line Equipment Completed.6) Support and Hanger installation Completed.7) Material Thickness Verification / Color Code8) P&ID Walk through in accordance with Isometric drawings.9) All instruments are disconnected or not.

BEFORE THE TESTING COMMENCES SOME OF THE GENERAL REQUIREMENT TO BE CHECK AND REVIEW.

1) Test Pressure to be used shall not less than 1.5 times the design pressure.2) Water to be used shall be fresh water and free from sediments. The Maximum Chloride content

shall be less than 30 ppm.

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3) For Pneumatic testing, the test medium shall be Air or any other non-flammable gas and the test pressure shall be 110 % of the design pressure. For pneumatic test, the soap solution spray shall be used during leakage detection.

4) The Temporary supports are to be examined to ensure that they will adequately support the line during testing.

TEST SEQUENCES ARE :1) Filling Test System Completely with water or Air.2) Fill the water from the down side.3) Open all vent valves during Water filling.4) Applying pressure gradually until the specified test pressure is reached.5) Holding time is 10 minutes minimum. The test pressure is attained until all welds and connection

have been examined. ( shall not over pressurize the system )6) After the test, the system was drained to minimize standing water in the line. Air blowing to be

performed to remove the remaining water.

VALVE INSPECTION AND TESTING : ( API 598 )

The following tests and examinations are specified in this standard.a) Shell Test.b) Back Seat Test.c) Low Pressure Closure Test.d) High Pressure Closure Test.e) Visual Examination of Castings.

SAMPLE OF PUNCH LIST ITEM :

1) To install permanent gasket after test.2) Apply Molykoat to all bolts.3) Bolt Length not correct.4) Apply Grease to all Valve spindles.5) Re install cap with Teflon tape.

VALVE INSTALLATION GUIDE :

a) The height of the hand wheel of normal operating valve shall not be more than 1800 mm above operating level. As alternative permanent plat form may be provided.

b) Maintenance valves more than 2000 mm above operating level for NPS 2” and larger shall be provided with chain operating with client approval.

Valve should not be positioned with their stem pointing down ward below horizontal with following exceptions :

a) No horizontally positioned stems in low temperature service.b) Butterfly valves shall not be installed with the spindle in the vertical position for services

where collection of dirt in the lower shaft bearing could occur.c) Gate valves installed around safety / relief valves and in flare lines shall be positioned

with the stem pointing horizontally.

127) What is Fractionation ?

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A Distillation Process Where in several distillates such as Wax Distillates, Gas oil, Heating oil, Naphtha and Fuel Gases are formed. Usual feed is the Crude oil.

128) What is Distillation?

A Process Wherein the lighters fluid is separated from the heavier fluid.

129) What type of support for horizontal vessel?

Saddle support.

130) What type of support for Vertical vessel?

Skirt support.

131) What is the minimum class rating for a Control Valve?300 lbs.

132) What is the minimum class rating of bypass valve?

300 lbs.

133) What is the minimum class rating for an orifice flange?

300 lbs.

134) What is the common material use for pipe, fittings, valves, flanges, gasket & bolts?

Pipe – A53, API 5LFittings – A234 Gr.BValves – ANSI B16.5Flanges – A105 Gr.11Gasket – ANSI – B16.5Bolts & Nuts – ANSI B1.1

135) What is the position of the reducer in the suction side of pump and its purpose?

It must be position top flat not to create bubbles of Air that will corrode the surface of the blade.

136) What is a Flare?

A system that disposes the plants waste gases.

137) What is HAZOP?

Hazop is hazards in the installation of Equipment and operability of the equipment.

138) What is the minimum spacing of platform ?

2.1 meters.

139) What is the minimum horizontal spacing for personnel?

1 meter.

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140) What is the minimum vertical spacing for personnel ?

2.1 meters.

141) What are the common basic functions of Instruments?

1) to sense 2) to transmit 3) to indicate 4) to record 5) to control.

142) Thermal Stresses : Changes in temperature of piping, due either to change in temperature

Of the environment or of the conveyed fluid, cause changes in length of the piping. This expansion or contraction in turn causes strains in piping, supports and attached equipment.

143) Flexibility in piping : To reduce strains in piping caused by substantial thermal movement, flexible and Expansion joints may be used. How ever the use of these joints may be minimized by Arranging piping in a flexible manner. Pipe can flex in a direction perpendicular to its Length, thus the longer an offset , or the deeper a loop, the more flexibility is gained.

144) Where to place the valves :

a) Preferably place valves in lines from headers ( on pipe racks ) in horizontal rather than vertical runs, so that lines can drain when the valves are closed.b) To avoid spooling unnecessary length of pipe, mount valves directly onto flanged equipment .c) A relief valve that discharges into a header should be placed higher than the header in order to drain into it.d) Locate heavy valves near suitable supports points. Flanges should be not closer than 12 inches to nearest support, so that installation is not hampered.

145) Utility station : Usually comprises four service lines carrying Steam, Utility Air, Service Water and Nitrogen.

146) Two Basic types of spring support :a) Variable Load.b) Constant Load.

147) Relief Headers :

Headers should be sized to handle adequately the large amounts of Vapor and liquid that may be discharged during major mishap. Relief Headers taken to knock out drums, receivers or incinerators are normally sloped.

148) Steam Pressure for Tracing :

Steam pressures in the range of 10 to 200 psig are used. Some times steam will be available at a suitable pressure for the tracing system.

149) Correct Pre heating temperature :a) A335 P9 ( all thk )………… 177*C over.b) A335 P11 ( all thk ) ………..149*C over.c) A53 Gr. B ( thk < 25 mm )…10 *C over.

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d) A106 Gr. B ( thk > 25 mm ) 79 *C over.

150) While GTAW welding at what wind speed do you have to install wind protection.

0.5 m / sec.

151) Chemical composition of Incoloy material :

Fe – Cr – Ni.

152) Strongest material at low temperature service :

A312 – TP304 ( C-0.8 / tensile strength 75 ksi / yield strength 30 ksi )

153) What should be the Internal Gap of the socket weld joint and what is the reason for leaving the gap? 1.6 mm minimum ( to avoid crack caused by thermal expansion when socket joint welding.)

154) Defects that cannot be detected with Visual Examination : Internal Porosity, Slag Inclusion, Lack of Fusion, Burn through, Tungsten Inclusion.

155) The difference between electrode E – 308 and E – 308L :E – 308L contains less Carbon than E – 308.

156) Four main parts of Spiral wound Gasket :Filler, Outer Ring, Inner Ring and Hoop.

157) RAISED FACE :Is 1/16” high for 150 and 300 lbs flanges, and ¼” high for all other pressure classes.250 psi cast iron flanges and flanged fittings also have the 1/16” raised face.

158) FLAT FACE :Most common uses are for mating with non – steel flanges on bodies of pumps, etc. and for mating 125 psi cast iron valve and fittings. Flat faced flanges are used with a GasketWhose outer diameter equals that of the flange- this reduces the danger of cracking a cast iron, bronze or plastic flange when the assembly is tightened.

159) RING JOINT FACING :Most efficient for high temperature and high pressure service. Ring joint facing is not prone to damage in handling as the surfaces in contact with the gasket are recessed. Use of facing of this type may increase as hollow metal O- ring gain acceptance for processChemical seals.

160) THREE ADVANTAGES OF USING STUD BOLTS ARE :a) the stud bolt is more easily removed if corroded.b) Confusion with other bolts at the site is avoided.c) Stud bolts in the less frequently used sizes and materials can be readily made

from round stock.

161) TWO PRINCIPAL TYPES OF FINISH ( FLANGE RAISED FACE ) ARE :a) serratedb) smooth.

162) SMOOTH FINISH :

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Is usually specially ordered and is available in two qualities. The smoother surface is termed “ cold water “ finish. The regular smooth finish shows no tool marks to the naked eye.

163) ORIFICE PLATE :Is a flat disc with a precisely made hole at its center, it offers a well defined obstruction to flow when inserted in a line. The resistance of the orifice sets up a pressure difference in the fluid either side of the plate, which can be used to measure the rate of flow.

164) JOINT USING FLANGE OF DIFFERENT RATINGS :Where flanges of different rating are bolted together, the rating of the joint shall not exceed that of the lower flange. Bolting torque shall be limited so that excessive loads will not be imposed on the lower rated flange in obtaining a tight joint.

165) NORMAL LOCATION FOR THE PRESSURE TEST GAUGE :Basically required Two nos. pressure gauges. One in the top side, and the other in the down side. Test pressure should be monitored only in the Top side pressure Gauge. Every 10 meter height, 1 barg head pressure to be added with the top side pressure readings.To control the accuracy of the readings, the pressure gauge range should be 1.5 times to 3.0 times of the test pressure. It is mandatory to use only the calibrated gauges.

166) ACCEPTANCE CRITERIA FOR INSPECTION OF 6” DIA, SCH. 40 BUTT WELDJOINT:a) Bevel Angle ………………………. 37.5* deg.( tolerance 2.5* )b) Root Gap…………………………... 1.6mm ( tolerance 0.8mm )c) Internal Alignment ( Hi- Lo )……… 1.6mm below.d) Root Face…………………………...1.6mm ( tolerance 0.8mm )

167) TWO REASONS FOR HAVING VENT HOLE ON REINFORCING PAD OF BRANCH CONNECTION :

a) To reveal leakage in the weld between branch and header.b) To allow venting during welding and heat treatment.

168) CROMIUM CONTENT OF THE FOLLOWING METAL :a) A335 Gr.P5………………0.5%b) A335 Gr.P9………………0.9%c) A335 Gr.P11……………..1 ¼ %d) A335 Gr.P22…………….. 2 ¼ %Page

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