How to Identify and Measure Fittings
Pipe size is an industry designation, not the actual size. View information about how to measure threaded and unthreaded pipe and pipe fittings.
More
Low-Pressure Steel Threaded Pipe Flanges
Use these flanges for low-pressure applications in noncorrosive environments. Bolt two flanges of the same size together with a gasket (sold separately) to create an access point within a line.
- For Use With: Air, Natural Gas, Oil, Steam, Water
- Pressure Class: 150
- Specifications Met:
NPT: ASME B16.5, ASTM A105, MSS SP-25
BSPT: ASTM A105 - Fittings: Use Class 125 or 150 iron and steel
- Pipe Nipples and Pipe: Use Schedule 40 steel
Bolt Hole | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Pipe Size  | Flange OD | For Bolt Dia. | Dia. | No. of | Bolt Circle Dia. | Max. Pressure | Max. Steam Pressure | Material | Each | |
NPT | ||||||||||
| 3 1/2 | 8 1/2" | 5/8" | 3/4" | 8 | 7" | 285 psi @ 72° F | 230 psi @ 300° F | Steel | 000000000 | 0000000 |
FM-Approved Low-Pressure Cast Iron Unthreaded Pipe Flanges
- For Use With: Air, Diesel Fuel, Gasoline, Natural Gas, Oil, Steam, Water
- Pressure Class: 125
- Specifications Met: ASME B1.20.1, ASME B16.1, ASTM A126, FM Approved
- Pipe Nipples and Pipe: Use Schedule 40 steel
- Fittings: Use Class 125 or 150 iron and steel
FM-approved for fire protection applications, these flanges are cast iron, so they're brittle and can be quickly opened by hitting them with a sledge hammer. Bolt them together with a gasket (not included) to create an access point within a low-pressure pipe line. All are cap flanges, which are also known as blind flanges. Use them in noncorrosive environments.
Bolt Hole | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Pipe Size | Flange OD | For Bolt Dia. | Dia. | No. of | Bolt Circle Dia. | Max. Pressure | Max. Steam Pressure | Each | |
| 3 1/2 | 8 1/2" | 5/8" | 3/4" | 8 | 7" | 200 psi @ 72° F | 165 psi @ 300° F | 0000000 | 0000000 |
Water- and Steam-Resistant EPDM Pipe Gaskets with Bolt Holes
Made of EPDM rubber, these gaskets resist water, steam, and salt water. Commonly called full-face gaskets, they cover the entire face of flat-surface pipe flanges and align with the bolt holes.
Gaskets for ANSI class flanges are sized so all gasket specifications meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges. Gaskets for ANSI Class 300 flanges are compatible with medium-pressure pipe flanges.
| For Pipe Size | ID | OD | No. of Bolt Holes | Max. Pressure, psi | Temperature Range, °F | Hardness | Hardness Rating | Color | Each | |
1/16" Thick. | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
For ANSI Class 150 | ||||||||||
| 3 1/2 | 4" | 8 1/2" | 8 | 800 | -20° to 220° | Durometer 60A | Medium Hard | Black | 00000000 | 00000 |
For ANSI Class 300 | ||||||||||
| 3 1/2 | 4" | 9" | 8 | 800 | -20° to 220° | Durometer 60A | Medium Hard | Black | 00000000 | 0000 |
1/8" Thick. | ||||||||||
For ANSI Class 150 | ||||||||||
| 3 1/2 | 4" | 8 1/2" | 8 | 800 | -20° to 220° | Durometer 60A | Medium Hard | Black | 00000000 | 00000 |
For ANSI Class 300 | ||||||||||
| 3 1/2 | 4" | 9" | 8 | 800 | -20° to 220° | Durometer 60A | Medium Hard | Black | 00000000 | 00000 |
Water-Resistant Aramid/SBR Pipe Gaskets with Bolt Holes
Aramid fibers are blended with SBR rubber for resistance to water, inert gases, and abrasion. Commonly called full-face gaskets, these cover the entire face of flat-surface pipe flanges and align with the bolt holes. All gasket specifications are sized to meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges. Gaskets for ANSI Class 300 flanges are compatible with medium-pressure pipe flanges.
Oil-Resistant Compressible Buna-N Pipe Gaskets with Bolt Holes
Made of Buna-N rubber, these gaskets compress to ensure a tight seal. They resist oil, water, and salts. Commonly called full-face gaskets, they cover the entire face of flat-surface pipe flanges and align with the bolt holes.
Gaskets for ANSI class flanges are sized so all gasket specifications meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges. Gaskets for ANSI Class 300 flanges are compatible with medium-pressure pipe flanges.
Oil-Resistant Aramid/Buna-N Pipe Gaskets with Bolt Holes
These blended aramid fiber/Buna-N rubber gaskets resist oil, water, and aliphatic hydrocarbons such as ethylene. Commonly called full-face gaskets, they cover the entire face of flat-surface pipe flanges and align with the bolt holes.
Gaskets for ANSI class flanges are sized so all gasket specifications meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges. Gaskets for ANSI Class 300 flanges are compatible with medium-pressure pipe flanges.
Adhesive-back gaskets stay in place to make installation easier.
Oil-Resistant Aramid/Buna-N Pipe Gaskets with Bolt Holes and Fasteners
Each gasket comes with enough bolts and nuts to create a connection between two steel pipe flanges. Commonly called full-face gaskets, they cover the entire face of flat-surface pipe flanges and align with the bolt holes. They’re made from blended aramid fiber/Buna-N rubber and resist oil, water, and aliphatic hydrocarbons such as ethylene.
Gaskets for ANSI class flanges are sized so all gasket specifications meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges. Gaskets for ANSI Class 300 flanges are compatible with medium-pressure pipe flanges.
Ultra-Chemical-Resistant Compressible PTFE Pipe Gaskets with Bolt Holes
Also known as Gore GR, these soft expanded PTFE gaskets are more compressible than pure PTFE to ensure a tight seal. They are chemically inert (except to molten alkali metal and fluorine compounds). Commonly called full-face gaskets, they cover the entire face of flat-surface pipe flanges and align with the bolt holes. All gasket specifications are sized to meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges. Gaskets for ANSI Class 300 flanges are compatible with medium-pressure pipe flanges.
Ultra-Chemical-Resistant Food Industry
Compressible PTFE Pipe Gaskets with Bolt Holes
Made of FDA-listed material for use with food and beverage, these soft expanded PTFE gaskets compress to ensure a tight seal. They are chemically inert (except to molten alkali metal and fluorine compounds). Commonly called full-face gaskets, they cover the entire face of flat-surface pipe flanges and align with the bolt holes. All gasket specifications are sized to meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges. Gaskets for ANSI Class 300 flanges are compatible with medium-pressure pipe flanges.
| For Pipe Size | ID | OD | No. of Bolt Holes | Temperature Range, °F | Color | Specifications Met | Each | |
1/16" Thick. | ||||||||
|---|---|---|---|---|---|---|---|---|
For ANSI Class 150 | ||||||||
| 3 1/2 | 4" | 8 1/2" | 8 | -450° to 350° | White | FDA Compliant 21 CFR 177.1550, USP Class VI | 0000000 | 000000 |
1/8" Thick. | ||||||||
For ANSI Class 150 | ||||||||
| 3 1/2 | 4" | 8 1/2" | 8 | -450° to 350° | White | FDA Compliant 21 CFR 177.1550, USP Class VI | 0000000 | 00000 |
Ultra-Chemical-Resistant Compressible PTFE Pipe
Gaskets with Bolt Holes for Low Stress-to-Seal Flanges
Form a seal even under the low torque needed for fiberglass flanges. Also known as Gore UPG, these gaskets are made from soft expanded PTFE. They fill gaps in pitted and corroded flanges and make up for uneven bolt load resulting from vibration and incorrect installation. They’re chemically inert (except to molten alkali metal and fluorine compounds). Commonly called full-face gaskets, they cover the entire face of flat-surface pipe flanges and align with the bolt holes. All gasket specifications are sized to meet ANSI standards. They’re compatible with ANSI Class 150 low-pressure pipe flanges.
1/16" Thick. | |||||||
|---|---|---|---|---|---|---|---|
| For Pipe Size | ID | OD | No. of Bolt Holes | Temperature Range, °F | Color | Each | |
For ANSI Class 150 | |||||||
| 3 1/2 | 4" | 8 1/2" | 8 | -450° to 600° | White | 00000000 | 000000 |
Ultra-Chemical-Resistant PTFE Pipe Gaskets with Bolt Holes
Made of pure PTFE, these gaskets have a slippery surface that prevents sticking. They are chemically inert (except to molten alkali metal and fluorine compounds). Commonly called full-face gaskets, these cover the entire face of flat-surface pipe flanges and align with the bolt holes. All gasket specifications are sized to meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges.
Ultra-Chemical-Resistant High-Strength PTFE Pipe Gaskets with Bolt Holes
A fiberglass filler in these PTFE gaskets provides strength to prevent them from thinning out when compressed. They resist hydrocarbons, solvents, refrigerants, and moderate concentrations of acids. Commonly called full-face gaskets, they cover the entire face of flat-surface pipe flanges and align with the bolt holes. All gasket specifications are sized to meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges.
| For Pipe Size | ID | OD | Thick. | No. of Bolt Holes | Max. Pressure, psi | Temperature Range, °F | Color | Each | |
For ANSI Class 150 | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 3 1/2 | 4" | 8 1/2" | 1/16" | 8 | 800 | -450° to 500° | Blue | 0000000 | 000000 |
Chemical-Resistant Viton® Fluoroelastomer Pipe Gaskets with Bolt Holes
These gaskets resist boric acid, citric acid, isopropyl alcohol, fuel, oil, and transmission fluid. Commonly called full-face gaskets, they cover the entire face of flat-surface pipe flanges and align with the bolt holes.
Gaskets for ANSI class flanges are sized so all gasket specifications meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges.
High-Temperature Graphite Pipe Gaskets with Bolt Holes
Able to withstand temperatures up to 750° F, these graphite gaskets have a stainless steel insert for strength to handle pressure up to 1,000 psi. Commonly called full-face gaskets, they cover the entire face of flat-surface pipe flanges and align with the bolt holes.
All gaskets are sized to meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges.
| For Pipe Size | ID | OD | Thick. | No. of Bolt Holes | Max. Pressure, psi | Temperature Range, °F | Color | Each | |
For ANSI Class 150 | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 3 1/2 | 4" | 8 1/2" | 1/16" | 8 | 1,000 | -325° to 750° | Gray | 00000000 | 000000 |
High-Temperature Silicone Pipe Gaskets with Bolt Holes
Resistant to water and salts, these silicone rubber gaskets can handle temperatures up to 450° F. Commonly called full-face gaskets, they cover the entire face of flat-surface pipe flanges and align with the bolt holes. Gaskets are compatible with low-pressure pipe flanges; all gasket specifications are sized to meet ANSI standards.
High-Temperature Oil-Resistant Carbon/Buna-N Pipe Gaskets with Bolt Holes
Carbon is blended with Buna-N rubber for gaskets that are unaffected by oil and temperatures up to 650° F. Commonly called full-face gaskets, they cover the entire face of flat-surface pipe flanges and align with the bolt holes. Gaskets are compatible with low-pressure pipe flanges; all gasket specifications are sized to meet ANSI standards.
| For Pipe Size | ID | OD | Thick. | No. of Bolt Holes | Max. Pressure, psi | Temperature Range, °F | Color | Each | |
For ANSI Class 150 | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 3 1/2 | 4" | 8 1/2" | 1/16" | 8 | 2,000 | -100° to 650° | Black | 0000000 | 000000 |
High-Temperature Metallic Pipe Gaskets
a Flat-Surface
Pipe Flange
Also known as spiral-wound gaskets, these have a 1/8” thick carbon steel outer ring and a 304 stainless steel sealing element with a graphite-based filler. The metal construction provides structural strength. These gaskets can be used with both flat-surface and raised-surfaces pipe flanges; they fit the surface inside the bolt holes and do not interfere with the bolt connection.
Gaskets for ANSI class flanges are sized so all gasket specifications meet ANSI standards. Gaskets for ANSI Class 600 flanges are compatible with high-pressure pipe flanges.
Sealing Element | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| For Pipe Size | ID | OD | Thick. | OD | Wd. | Max. Pressure | Temperature Range, °F | Material | Sealing Element Material | Sealing Element Filler Material | Specifications Met | Each | |
| 3 1/2 | 4 1/8" | 6 3/8" | 1/8" | 5 1/4" | 0.175" | Not Rated | -50° to 840° | Carbon Steel | 304 Stainless Steel | Graphite | ASME B16.20 | 000000000 | 000000 |
Long-Life High-Temperature Metallic Pipe Gaskets
a Flat-Surface
Pipe Flange
A space between the outer ring and the sealing element prevents the element from being squeezed inward and contaminating the process line. Also known as spiral-wound gaskets, these have a 1/8” thick carbon steel outer ring and a 304 stainless steel sealing element with a graphite-based filler. The metal construction of these gaskets provides structural strength. They compensate for flange movement caused by vibration and pressure. These gaskets can be used on both flat-surface and raised-surface pipe flanges; they fit inside the bolt holes and do not interfere with the bolt connections. All gasket specifications are sized to meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges. Gaskets for ANSI Class 300 flanges are compatible with medium-pressure pipe flanges.
Sealing Element | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| For Pipe Size | ID | OD | Thick. | OD | Wd. | Max. Pressure | Temperature Range, °F | Material | Sealing Element Material | Sealing Element Filler Material | Each | |
For ANSI Class 150 | ||||||||||||
| 3 1/2 | 4 1/8" | 6 3/8" | 1/8" | 4.859" | 0.175" | Not Rated | -40° to 850° | Carbon Steel | 304 Stainless Steel | Graphite | 0000000 | 000000 |
For ANSI Class 300 | ||||||||||||
| 3 1/2 | 4 1/8" | 6 1/2" | 1/8" | 4.859" | 0.175" | Not Rated | -40° to 850° | Carbon Steel | 304 Stainless Steel | Graphite | 0000000 | 00000 |
High-Temperature Silicone Pipe Gaskets
In addition to withstanding temperatures up to 450° F, these silicone rubber gaskets resist water and salts. Also known as ring gaskets, use them with raised-surface pipe flanges; they fit the surface inside the bolt holes and do not interfere with the bolt connection. Gaskets are compatible with low-pressure pipe flanges; all gasket specifications are sized to meet ANSI standards.
Ultra-Chemical-Resistant Compressible PTFE Pipe Gaskets
Also called Gore GR ring gaskets, these gaskets are made of soft expanded PTFE, which is more compressible than pure PTFE to ensure a tight seal. They are chemically inert (except to molten alkali metal and fluorine compounds). Use them with raised-surface pipe flanges; they fit the surface inside the bolt holes and do not interfere with the bolt connection. All gasket specifications are sized to meet ANSI standards. Gaskets for ANSI Class 300 flanges are compatible with medium-pressure pipe flanges.
Ultra-Chemical-Resistant Food Industry Compressible PTFE Pipe Gaskets
These soft expanded PTFE gaskets are made of FDA-listed material for use with food and beverage. They are chemically inert (except to molten alkali metal and fluorine compounds) and are compressible to ensure a tight seal. Also known as ring gaskets, use them with raised-surface pipe flanges; they fit the surface inside the bolt holes and do not interfere with the bolt connection. All gasket specifications are sized to meet ANSI standards. Gaskets for ANSI Class 300 flanges are compatible with medium-pressure pipe flanges.
Chemical-Resistant Viton® Fluoroelastomer Pipe Gaskets
Resistant to boric acid, citric acid, isopropyl alcohol, fuel, oil, and transmission fluid, these gaskets are also known as ring gaskets. They are for use on raised-surface pipe flanges; they fit the surface inside the bolt holes and do not interfere with the bolt connection.
Gaskets for ANSI class flanges are sized so all gasket specifications meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges.
Water- and Steam-Resistant EPDM Pipe Gaskets
Resistant to water, steam, and salt water, these gaskets are EPDM rubber. Commonly called ring gaskets, use them with raised-surface pipe flanges; they fit the surface inside the bolt holes and do not interfere with the bolt connection.
Gaskets for ANSI class flanges are sized so all gasket specifications meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges. Gaskets for ANSI Class 300 flanges are compatible with medium-pressure pipe flanges.
Adhesive-back gaskets stay in place to make installation easier.
| For Pipe Size | ID | OD | Max. Pressure, psi | Temperature Range, °F | Hardness | Hardness Rating | Color | Each | |
1/16" Thick. | |||||||||
|---|---|---|---|---|---|---|---|---|---|
For ANSI Class 150 | |||||||||
| 3 1/2 | 4" | 6 3/8" | 800 | -20° to 220° | Durometer 60A | Medium Hard | Black | 00000000 | 00000 |
1/8" Thick. | |||||||||
For ANSI Class 150 | |||||||||
| 3 1/2 | 4" | 6 3/8" | 800 | -20° to 220° | Durometer 60A | Medium Hard | Black | 0000000 | 0000 |
For ANSI Class 300 | |||||||||
| 3 1/2 | 4" | 6 1/2" | 800 | -20° to 220° | Durometer 60A | Medium Hard | Black | 00000000 | 0000 |
Adhesive | 1/16" Thick. | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| For Pipe Size | ID | OD | Max. Pressure, psi | Temperature Range, °F | Hardness | Hardness Rating | Color | Type | Max. Temperature, ° F | Each | |
For ANSI Class 150 | |||||||||||
| 3 1/2 | 4" | 6 3/8" | 800 | -20° to 220° | Durometer 60A | Medium Hard | Black | Acrylic | 105º | 0000000 | 00000 |
For ANSI Class 300 | |||||||||||
| 3 1/2 | 4" | 6 1/2" | 800 | -20° to 220° | Durometer 60A | Medium Hard | Black | Acrylic | 105º | 0000000 | 0000 |
Water- and Abrasion-Resistant SBR Pipe Gaskets
The all-SBR rubber construction of these gaskets provides better abrasion resistance than blended aramid/SBR gaskets. Also known as ring gaskets, use them with raised-surface pipe flanges; they fit the surface inside the bolt holes and do not interfere with the bolt connection. Gaskets are compatible with low-pressure pipe flanges; all gasket specifications are sized to meet ANSI standards.
| For Pipe Size | ID | OD | Thick. | Max. Pressure, psi | Temperature Range, °F | Hardness | Hardness Rating | Color | Pkg. Qty. | Pkg. | |
For ANSI Class 150 | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 3 1/2 | 4" | 6 3/8" | 1/8" | 800 | -20° to 170° | Durometer 75A | Hard | Red | 6 | 0000000 | 000000 |
Water-Resistant Aramid/SBR Pipe Gaskets
Aramid fibers and SBR rubber are blended for resistance to abrasion, water, and inert gases. Also known as ring gaskets, use these gaskets with raised-surface pipe flanges; they fit the surface inside the bolt holes and do not interfere with the bolt connection. All gasket specifications are sized to meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges. Gaskets for ANSI Class 300 flanges are compatible with medium-pressure pipe flanges.
Water- and Refrigerant-Resistant Neoprene Pipe Gaskets
These neoprene gaskets resist water, refrigerants, and salts. Commonly called ring gaskets, use them with raised-surface pipe flanges; they fit the surface inside the bolt holes and do not interfere with the bolt connection. They are compatible with low-pressure pipe flanges; all gasket specifications are sized to meet ANSI standards.
| For Pipe Size | ID | OD | Thick. | Max. Pressure, psi | Temperature Range, °F | Hardness | Hardness Rating | Color | Pkg. Qty. | Pkg. | |
For ANSI Class 150 | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 3 1/2 | 4" | 6 3/8" | 1/8" | 1,000 | -20° to 170° | Durometer 60A | Medium Hard | Black | 6 | 00000000 | 000000 |
Oil-Resistant Aramid/Buna-N Pipe Gaskets
In addition to oil, these blended aramid fiber/Buna-N rubber gaskets resist water and aliphatic hydrocarbons such as ethylene. Also known as ring gaskets, use them with raised-surface pipe flanges; they fit the surface inside the bolt holes and do not interfere with the bolt connection.
Gaskets for ANSI class flanges are sized so all gasket specifications meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges. Gaskets for ANSI Class 300 flanges are compatible with medium-pressure pipe flanges.
Adhesive-back gaskets stay in place to make installation easier.
Oil-Resistant Aramid/Buna-N Pipe Gaskets with Fasteners
Furnished with enough nuts and bolts to create a connection between two steel pipe flanges. These gaskets, also known as ring gaskets, are for use on raised-surface pipe flanges; they fit the surface inside the bolt holes and do not interfere with the bolt connection. They’re made from blended aramid fiber/Buna-N rubber and resist oil, water, and aliphatic hydrocarbons such as ethylene. Gaskets are compatible with low-pressure pipe flanges; all gasket specifications are sized to meet ANSI standards.
| For Pipe Size | ID | OD | Thick. | Bolt Screw Size | Bolt Lg. | Max. Pressure, psi | Temperature Range, °F | Color | Each | |
For ANSI Class 150 | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 3 1/2 | 4" | 6 3/8" | 1/16" | 5/8" | 3" | 725 | -40° to 450° | Green | 0000000 | 000000 |
Oil-Resistant Compressible Buna-N Pipe Gaskets
These compressible Buna-N rubber gaskets ensure a tight seal. They resist oil, water, and salts. Also known as ring gaskets, use them with raised-surface pipe flanges; they fit the surface inside the bolt holes and do not interfere with the bolt connection. All gasket specifications are sized to meet ANSI standards. Gaskets for ANSI Class 150 flanges are compatible with low-pressure pipe flanges.