Cap/Plug Flanges | McMaster-Carr

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For Use With

Acetic Acid (White Vinegar) (5% Concentration)

Acetic Acid (White Vinegar) (10% Concentration)

Acetic Acid (White Vinegar) (75% Concentration)

Specifications Met

Shape

For Fitting Schedule

Tube OD

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Maximum Pressure @ Temperature

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Export Control Classification Number (ECCN)

2A992

2B999

EAR99

DFARS Specialty Metals

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311 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.

Low-Pressure Stainless Steel
Unthreaded Pipe Flanges

Bolt two same-size flanges together with a gasket to create an access point within a pipe line.

High-Pressure Stainless Steel
Unthreaded Pipe Flanges

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

High-Pressure Stainless Steel
Unthreaded SAE Pipe Flanges

Also known as Code 61 SAE hydraulic flanges.

Low-Pressure Steel Unthreaded Pipe Flanges

Bolt two flanges of the same size together with a gasket to create an access point in a pipe line.

Low-Pressure Steel Unthreaded
Pipe Flanges for Low Temperatures

Even in temperatures as low as -46°, these A350 LF2 steel flanges won’t become brittle, so they absorb impact better than other low-pressure steel flanges.

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.

High-Pressure Steel Unthreaded Pipe Flanges

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

High-Pressure Steel Unthreaded SAE Pipe Flanges

Also known as Code 61 SAE hydraulic flanges.

Extreme-Pressure Steel Unthreaded Pipe Flanges

For excellent strength in extreme-pressure applications, choose these heavy duty Pressure Class 1500 flanges.

Aluminum Unthreaded Pipe Flanges

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

Low-Pressure Aluminum Threaded Pipe Fittings

In addition to being lightweight, these aluminum fittings offer good corrosion resistance. Use them in low-pressure flow applications.

Brass and Bronze Unthreaded Pipe Flanges

Bolt these flanges to another same-size flange with a gasket to create an access point within a pipe line. They are also known as Silbraze flanges.

Plastic Pipe and Pipe Fittings

Thick-Wall Plastic Pipe Flanges for Water

Bolt two same-size flanges together with a gasket to create an access point within a line. They are also known as Pressure Class 150 flanges. They have thick, strong walls to handle heavy duty industrial plumbing and water supply applications, such as water processing, waste water treatment, and irrigation.

CPVC Pipe Flanges for Hot Water

Bolt two same-size flanges together with a gasket to create an access point within a line. They are also known as Pressure Class 150 flanges. Use in high-temperature plumbing and water supply applications up to 200° F.

UV-Resistant Polypropylene
Pipe Flanges for Chemicals

Use these polypropylene flanges in outdoor environments—they resist the damaging effects of ultraviolet light. They have the chemical resistance to stand up to acids, solvents, and other harsh substances. Bolt two same-size flanges together with a gasket to create an access point within a line. Flanges are also known as Pressure Class 150 flanges.

Fiberglass Pipe Flanges for Corrosive Chemicals

Flanges have excellent corrosion resistance to handle a wide range of acids and other highly-corrosive chemicals. Use in metal surface treating applications, plating solution lines, and other chemical process applications. They are reinforced with fiberglass layers for better strength and durability than any of our other pipe flanges for chemicals. Bolt two same-size flanges together with a gasket to create an access point within a line.

Plastic Pipe Fittings for Gasoline

Use these plastic fittings to connect gasoline fuel lines to machines and equipment. They have excellent corrosion resistance as well as high strength and impact resistance.

Tube Fittings for Metal Tubing

Quick-Clamp High-Vacuum
Fittings for Stainless Steel Tubing

Also known as KF, QF, and NW fittings, these fittings are for high-vacuum applications, such as vacuum coating and heat treating, leak testing, and analyzing gases.

Ultra-High-Vacuum Flanges and
Fittings for Stainless Steel Tubing

Create access points in ultra-high-vacuum lines or chambers by bolting two same-size flanges together with a copper gasket between them. The flanges’ sharp edges dig into the copper gasket and form an extremely tight seal, which means they handle higher vacuum pressures than other high-vacuum fittings with rubber gaskets.

Quick-Clamp High-Vacuum
Fittings for Aluminum Tubing

For use in high-vacuum systems, these fittings use a metal reinforced O-ring to create an airtight seal. Also known as KF, QF, and NW fittings, they’re used for high-vacuum applications such as vacuum coating and heat treating, leak testing, and analyzing gases.