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Weld let and Sockolet are basically self-reinforced fittings.

Weld let is USED for BUTT weld branch connection where standard tee is not available due to SIZE restrictions and the PIPING is of critical / high-pressure service. Sockolet is used for socket welding branch connection, which require reinforcing PAD.

Weld let and Sockolet are basically self-reinforced fittings.

Weld let is used for Butt weld branch connection where standard tee is not available due to size restrictions and the piping is of critical / high-pressure service. Sockolet is used for socket welding branch connection, which require reinforcing pad.

IBR: Indian BOILER Regulation Act.

STEAM LINES with conditions listed bellow comes under IBR purview: –

• Lines for which design PRESSURE is 3.5 kg/sq. cm and above.
• Line size above 10” having design pressure 1.0 kg/sq. cm and above.
• Boiler feed water lines to steam generator, CONDENSATE lines to steam generator and flash drum.

IBR: Indian Boiler Regulation Act.

Steam lines with conditions listed bellow comes under IBR purview: –

The THUMB rule is that the minimum distance between adjacent butt WELDS is 1D. If not, it is never closer than 1-1/2″. This is supposedly to prevent the overlap of HAZe. Minimum spacing of circumferential welds between centerlines shall not be less than 4 times the pipe wall thickness or 25 MM WHICHEVER is greater.

The thumb rule is that the minimum distance between adjacent butt welds is 1D. If not, it is never closer than 1-1/2″. This is supposedly to prevent the overlap of HAZe. Minimum spacing of circumferential welds between centerlines shall not be less than 4 times the pipe wall thickness or 25 mm whichever is greater.

Piping which is recognized as providing the most UNIFORM application of heat to the process, as well as maintaining the most uniform processing temperatures where STEAM tracing is not capable of maintaining the temperature of fluid constant. Usually used for MOLTEN sulphur, POLYMERS service.

Piping which is recognized as providing the most uniform application of heat to the process, as well as maintaining the most uniform processing temperatures where steam tracing is not capable of maintaining the temperature of fluid constant. Usually used for molten sulphur, Polymers service.

HPV – For REMOVING Air during Hydrotest.

LPD – For DRAINING water after CONDUCTING Hydrotest.

HPV – For removing Air during Hydrotest.

LPD – For draining water after conducting Hydrotest.

There is the chance of ICE FORMATION during normal operation and since ice FLOWS from the bottom of the pipe it will BLOCK the BRANCH pipe connection.

There is the chance of ice formation during normal operation and since ice flows from the bottom of the pipe it will block the branch pipe connection.

When fluid is Gas, AIR or Steam and CRYOGENIC SERVICE – Topside.

When Fluid is LIQUID – Bottom Side.

When fluid is Gas, Air or Steam and Cryogenic Service – Topside.

When Fluid is Liquid – Bottom Side.

ASTM A53 pipes are MAINLY USED for utility services whereas A106 Gr. B pipes are used for high PRESSURE & high temperature services.

ASTM A53 pipes are mainly used for utility services whereas A106 Gr. B pipes are used for high Pressure & high temperature services.

Above 18” ERW pipes are used. Below 18” SEAMLESS pipes are used. Seamless pipes can SUSTAIN higher temperature & PRESSURE.

Above 18” ERW pipes are used. Below 18” seamless pipes are used. Seamless pipes can sustain higher temperature & pressure.

Use depends UPON the AVAILABILITY of PIPES. NOTHING functional DIFFERENCE.

Use depends upon the availability of pipes. Nothing functional difference.

No. Air pockets may form if CONCENTRIC reducer is used at pump suction, which results in CAVITATION and cause DAMAGE to Pump. To avoid this problem, ECCENTRIC Reducer with flat side up (FSU) is used in Pump Suction.

No. Air pockets may form if concentric reducer is used at pump suction, which results in Cavitation and cause damage to Pump. To avoid this problem, Eccentric Reducer with flat side up (FSU) is used in Pump Suction.

Eccentric reducers = Pump suction to AVOID Cavitation, to maintain elevation (BOP) in rack.

CONCENTRIC reducers = Pump DISCHARGE, vertical PIPELINE ETC.

Eccentric reducers = Pump suction to avoid Cavitation, to maintain elevation (BOP) in rack.

Concentric reducers = Pump discharge, vertical pipeline etc.

Long radius elbow are used for small pressure drop WHEREAS short radius elbow are used for high pressure drops. For CATALYST FLOWS vary long radius ELBOWS are used.

Long radius elbow are used for small pressure drop whereas short radius elbow are used for high pressure drops. For catalyst flows vary long radius elbows are used.

1D (Where “D” is the DIAMETER of the PIPE.)

1D (Where “D” is the diameter of the pipe.)

1.5D (Where “D” is the DIAMETER of the PIPE.)

1.5D (Where “D” is the diameter of the pipe.)

From the size 14” and onwards NB = OD of PIPE.

From the size 14” and onwards NB = OD of pipe.

Pipe is identified by NB and THICKNESS is defined by Schedule whereas Tube is identified by OD & its thickness as BWG (BIRMINGHAM WIRE gauge or 1/100 inch).

Pipe is identified by NB and thickness is defined by Schedule whereas Tube is identified by OD & its thickness as BWG (Birmingham wire gauge or 1/100 inch).

Galvanized steel MATERIALS shall be used for drinking WATER, instrument air and NI LINES (LP).

Galvanized steel materials shall be used for drinking water, instrument air and NI lines (LP).

Stainless steel materials shall be USED for CORROSIVE FLUID.

Stainless steel materials shall be used for corrosive fluid.

Alloy STEEL MATERIALS shall be USED for temperature above 426 C°.

Alloy steel materials shall be used for temperature above 426 C°.

Carbon STEEL MATERIALS shall be USED for temperature up to 425C°.

Carbon steel materials shall be used for temperature up to 425C°.

PIPE FITTINGS are classified based on end connection as: –

• Socket weld fittings.
• Screwed end fittings.
• Beveled end or BUTT weld fittings.
• Spigot socket fittings.
• BUTTRESS end fittings.

Pipe fittings are classified based on end connection as: –

C. °C or below – 28°Flanged joints USING low STRENGTH CARBON steel SHALL not be used above 200.

C. °C or below – 28°Flanged joints using low strength carbon steel shall not be used above 200.

Rating spiral WOUND GASKET on flanges other#ASME B16.5 does not RECOMMEND the use of 150 than WELDING neck and lapped joint type.

Rating spiral wound gasket on flanges other#ASME B16.5 does not recommend the use of 150 than welding neck and lapped joint type.

125-250 AARH FINISH.

125-250 AARH finish.

Spiral WOUND gaskets are PROVIDED with carbon STEEL EXTERNAL ring called centering ring.

Spiral wound gaskets are provided with carbon steel external ring called centering ring.

For very HIGH temperature SERVICES, GRAPHITE filler is USED.

For very high temperature services, graphite filler is used.

The most commonly used MATERIAL for SPIRAL wound metallic GASKET WINDING is: –

• Austenitic stainless steel 304 with asbestos filler.
• Austenitic stainless steel 316 with asbestos filler.
• Austenitic stainless steel 321 with asbestos filler.

The most commonly used material for spiral wound metallic gasket winding is: –

The selection of material of construction for GASKET winding DEPENDS upon: –

• The corrosive NATURE and concentration of fluid being carried.
• The operating temperature of the fluid.
• The relative cost of alternate winding material.

The selection of material of construction for Gasket winding depends upon: –

SPIRAL WOUND METALLIC GASKET.

Spiral Wound Metallic Gasket.

COMPRESSED ASBESTOS FIBRE.

Compressed Asbestos Fibre.

Based on the type of construction, GASKETS are classified as: –

• Full FACE.
• SPIRAL wound metallic.
• Ring type.
• METAL jacketed.
• Inside BOLT circle.

Based on the type of construction, gaskets are classified as: –

Concentric serration are insisted for face finish where the FLUID being CARRIED has very low DENSITY and can find leakage PATH through CAVITY.

Concentric serration are insisted for face finish where the fluid being carried has very low density and can find leakage path through cavity.

The SERRATION on flanges is SPECIFIED by the number, which is the ARITHMETIC Average Rough Height (AARH).

The serration on flanges is specified by the number, which is the Arithmetic Average Rough Height (AARH).

• CONCENTRIC
• SPIRAL (PHONOGRAPHIC)

The smooth finish flange is PROVIDED when metallic GASKET is provided and SERRATED finish flange is provided when non-metallic gasket is provided.

The smooth finish flange is provided when metallic gasket is provided and serrated finish flange is provided when non-metallic gasket is provided.

Flanges are CLASSIFIED based on FACE finish as: –

• Smooth finish.
• SERRATED finish.

Flanges are classified based on face finish as: –

Flanges are classified based on facing as: –

• Flat FACE. (FF)
• Raised face. (R/F)
• Tongue and GROOVE. (T/G)
• MALE and female. (M/F)
• RING type JOINT. (RTJ)

Flanges are classified based on facing as: –

Flanges are classified BASED on PRESSURE temperature ratings as: –

• #A. 150
• #B. 300
• #C. 400
• #D. 600
• #E. 900
• #F. 1500
• #G. 2500

Pressure temperature rating carts in the standard ASME B16.5 specify the non-shock working GAUGE pressure to which the flange can be subjected to at a particular temperature.

Flanges are classified based on pressure temperature ratings as: –

Pressure temperature rating carts in the standard ASME B16.5 specify the non-shock working gauge pressure to which the flange can be subjected to at a particular temperature.

Flanges can be classified based on pipe ATTACHMENT as: –

Slip – on. : – The Slip-on type flanges are attached by welding inside as well as outside. These flanges are of forged construction.

Socket Weld. : – The Socket Weld flanges are welded on ONE side only. These are used for small BORE lines only.

Screwed. : – The Screwed-on flanges are used on pipelines where welding cannot be carried out.

Lap Joint. : – The Lap Joint flanges are used with stub ends. The stub ends are welded with pipes & flanges are kept loose over the same.

Welding Neck. : – The Welding neck flanges are attached by butt welding to the pipe. These are used mainly for CRITICAL services where the weld joints need radiographic inspection.

Blind. : – The Blind flanges are used to close the ends which need to be reopened.

Reducing. : – The reducing flanges are used to connect between larger and smaller sizes without using a reducer. In case of reducing flanges, the thickness of FLANGE should be that of the higher diameter.

Integral. : – Integral flanges are those, which are cast along with the piping component or equipment.

Flanges can be classified based on pipe attachment as: –

Slip – on. : – The Slip-on type flanges are attached by welding inside as well as outside. These flanges are of forged construction.

Socket Weld. : – The Socket Weld flanges are welded on one side only. These are used for small bore lines only.

Screwed. : – The Screwed-on flanges are used on pipelines where welding cannot be carried out.

Lap Joint. : – The Lap Joint flanges are used with stub ends. The stub ends are welded with pipes & flanges are kept loose over the same.

Welding Neck. : – The Welding neck flanges are attached by butt welding to the pipe. These are used mainly for critical services where the weld joints need radiographic inspection.

Blind. : – The Blind flanges are used to close the ends which need to be reopened.

Reducing. : – The reducing flanges are used to connect between larger and smaller sizes without using a reducer. In case of reducing flanges, the thickness of flange should be that of the higher diameter.

Integral. : – Integral flanges are those, which are cast along with the piping component or equipment.