Class 125 Pipe Flanges | McMaster-Carr

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256 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.

Metal Pipe and Pipe Fittings

Low-Pressure Steel Threaded Pipe Flanges

These flanges are for low-pressure applications in noncorrosive environments.

FM-Approved Low-Pressure
Cast Iron Threaded Pipe Flanges

Suitable for use in fire-protection applications, these flanges are brittle and can be quickly opened with the strike of a sledge hammer.

Low-Pressure Galvanized
Steel Threaded Pipe Flanges

The galvanized finish on these Pressure Class 150 flanges provides fair corrosion resistance.

FM-Approved Low-Pressure Cast
Iron Unthreaded Pipe Flanges

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.

Steel Bleed Rings

Access the inside of lines, so you can vent pressure, drain liquid, or take samples. Made of steel, these bleed rings should be used in dry environments to prevent rusting.

Stainless Steel Bleed Rings

Create an access point in systems where corrosion is a concern. Made of stainless steel, these bleed rings resist rusting.

Aluminum Unthreaded Pipe Flanges

Use these unthreaded flanges in low-pressure applications. Also known as Pressure Class 125 flanges.

Low-Pressure Aluminum Threaded Pipe Flanges

Also known as Pressure Class 125 flanges, these are for use in low-pressure applications. Flanges are aluminum, which is lightweight with good corrosion resistance.

Low-Pressure Brass and
Bronze Threaded Pipe Flanges

Also known as Pressure Class 150 flanges, these brass flanges are designed for low-pressure applications.

Expansion Joint Reducers with Flanged Ends

Connect different pipe sizes in your line while adding a point of flexibility between them. These expansion joints absorb movement between two connected pipes to reduce stress, vibration, and noise.

Hex Head Screw and Nut Kits for Pipe Flanges

Stainless Steel Hex Screw
and Nut Kits for Pipe Flanges

Join standard-sized stainless steel and aluminum pipe flanges in corrosive conditions.

Steel Hex Screw and Nut Kits for Pipe Flanges

Connect standard-sized steel and cast iron pipe flanges. These kits come with the right size and number of screws and nuts for the bolt holes in each pipe size.

Stainless Steel Heavy Hex Screw
and Nut Kits for Pipe Flanges

Connect standard-size stainless steel pipe flanges with these kits—they come with screws and nuts in the right size and number to match the bolt holes. The screw heads are 10% wider than a standard hex head, so they spread force over a larger area, and you can tighten with more torque.

Steel Heavy Hex Screw and
Nut Kits for Pipe Flanges

Join standard-sized steel and cast iron pipe flanges—these kits come with the screws and nuts in the right size and number to match the bolt holes. The screw heads and nuts are 10% wider than standard hex fasteners, so they spread force over a larger area, and you can tighten with more torque.

Metal Pipe and Pipe Fittings

Low-Pressure Steel Threaded Pipe Flanges

FM-Approved Low-PressureCast Iron Threaded Pipe Flanges

Low-Pressure GalvanizedSteel Threaded Pipe Flanges

FM-Approved Low-Pressure CastIron Unthreaded Pipe Flanges

Steel Bleed Rings

Stainless Steel Bleed Rings

Aluminum Unthreaded Pipe Flanges

Low-Pressure Aluminum Threaded Pipe Flanges

Low-Pressure Brass andBronze Threaded Pipe Flanges

Expansion Joint Reducers with Flanged Ends

Expansion Joint Reducers with Flanged Ends

Hex Head Screw and Nut Kits for Pipe Flanges

Stainless Steel Hex Screwand Nut Kits for Pipe Flanges

Steel Hex Screw and Nut Kits for Pipe Flanges

Stainless Steel Heavy Hex Screwand Nut Kits for Pipe Flanges

Steel Heavy Hex Screw andNut Kits for Pipe Flanges

FM-Approved Low-Pressure
Cast Iron Threaded Pipe Flanges

Low-Pressure Galvanized
Steel Threaded Pipe Flanges

FM-Approved Low-Pressure Cast
Iron Unthreaded Pipe Flanges

Low-Pressure Brass and
Bronze Threaded Pipe Flanges

Stainless Steel Hex Screw
and Nut Kits for Pipe Flanges

Stainless Steel Heavy Hex Screw
and Nut Kits for Pipe Flanges

Steel Heavy Hex Screw and
Nut Kits for Pipe Flanges