20 1/2" OD Flanges | McMaster-Carr

Filter by

Pipe Size

Pressure Class

300

3000

Pipe Schedule

Fitting Connection

Material

For Use With

Fitting Type

Flange OD

Specifications Met

Bolt Hole Diameter

For Fitting Schedule

Number of Bolt Holes

Shape

Cap and Plug

Straight

Pipe Material

Steel

Maximum Steam Pressure @ Temperature

300 psi @ 300° F

Flanged Connection Surface

Raised

Fitting Material

Steel

Maximum Pressure @ Temperature

Bolt Circle Diameter

Fabrication

Bolt Diameter

U.S.–Mexico–Canada Agreement (USMCA) Qualifying

Yes

DFARS Specialty Metals

Exempt

Export Control Classification Number (ECCN)

REACH

RoHS

2 Products

About Pipe and Fittings

Measure your pipe and fittings to identify their pipe size, thread size, schedule, and thread type. Then, find compatible components.

High-Pressure Steel Unthreaded Pipe Flanges

Forged for extra strength, these heavy duty flanges can withstand high-pressure applications. Bolt two flat-surface flanges or two raised-surface flanges of the same size together with a gasket (sold separately) to create an access point in a pipe line.

Slip-on weld flanges have no internal stop; slide a pipe through the flange and weld on both sides.

Cap flanges are also known as blind flanges.

Slip-On Weld Flanges

Front

Raised Surface on Back

For Use With: Air, Hydraulic Fluid, Natural Gas, Oil, Steam, Water
Pressure Class: See table
Specifications Met: ASTM A105, ASME B16.5
Certification: Material Certificate with Traceable Lot Number and Test Report
Pipe Nipples and Pipe: Use Schedule 80 steel
Fittings: Use Class 3000 and Schedule 80 steel

			Bolt Hole
Pipe Size	Flange OD	For Bolt Dia.	Dia.	No. of	Bolt Circle Dia.	Max. Pressure	Max. Steam Pressure	Material		Each
Pressure Class 300
12	20 1/2"	1 1/4"	1 1/4"	16	17 3/4"	600 psi @ 72° F	300 psi @ 300° F	Steel	6806K414	0000000

Caps

Front

Raised Surface on Back

For Use With: Air, Hydraulic Fluid, Natural Gas, Oil, Steam, Water
Pressure Class: See table
Specifications Met: ASTM A105, ASME B16.5
Certification: Material Certificate with Traceable Lot Number and Test Report
Pipe Nipples and Pipe: Use Schedule 80 steel
Fittings: Use Class 3000 and Schedule 80 steel

			Bolt Hole
Pipe Size	Flange OD	For Bolt Dia.	Dia.	No. of	Bolt Circle Dia.	Max. Pressure	Max. Steam Pressure	Material		Each
Pressure Class 300
12	20 1/2"	1 1/4"	1 1/4"	16	17 3/4"	600 psi @ 72° F	300 psi @ 300° F	Steel	6806K421	0000000