Class 300 Pipe Flanges | McMaster-Carr

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681 Products

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.

Medium-Pressure Steel Threaded Pipe Flanges

With better strength than our low-pressure steel flanges, these are for use in medium-pressure applications.

Medium-Pressure Iron and
Steel Threaded Pipe Fittings

For use in noncorrosive environments, these fittings have better strength than our low-pressure iron and steel pipe fittings.

Medium-Pressure Galvanized
Steel Threaded Pipe Flanges

Also known as Pressure Class 300 flanges, these medium-pressure flanges have a galvanized finish for fair corrosion resistance.

Medium-Pressure Galvanized Iron
and Steel Threaded Pipe Fittings

A galvanized finish gives these fittings fair corrosion resistance. They have the strength to handle medium-pressure applications.

High-Pressure Steel Unthreaded Pipe Flanges

Forged for extra strength, these heavy duty unthreaded flanges can withstand high-pressure applications.

Thick-Wall Butt-Weld Steel Unthreaded Pipe Fittings

With thicker, stronger walls than our standard-wall butt-weld pipe fittings, these fittings stand up to your high strength applications.

High-Pressure Socket-Connect
Steel Unthreaded Pipe Fittings

Socket-connect fittings are easier to weld than butt-weld fittings because the fitting doesn't need to align perfectly to the pipe. Slide the pipe into the socket and weld.

Steel Bleed Rings

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

Stainless Steel Pipe and Pipe Fittings

High-Pressure Stainless Steel
Unthreaded Pipe Flanges

Use these heavy duty forged flanges for high-pressure applications.

Thick-Wall Butt-Weld Stainless
Steel Unthreaded Pipe Fittings

Butt-weld fittings allow for a smooth, flush connection that provides maximum flow.

Stainless Steel Bleed Rings

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

High-Pressure Stainless
Steel Threaded Pipe Flanges

Also known as ANSI flanges.

Flow-Control Flange Unions

Measure, throttle, and regulate the flow of liquids and gases in your line by adding an orifice plate to these unions.