Replacement Gasket for Bulkhead Fitting

The gasket is part of the bulkhead fitting

Bulkhead fittings create an opening through the wall of a tank for an inlet, outlet, drain, vent or connection to equipment. A gasket is included with the fitting, but it can also be purchased separately when replacement is required.

Once the fitting is installed with the appropriate gasket for the application, it can be connected to a valve, threaded fitting, Camlock fitting, hose or piping.

Agrico Plastics offers polypropylene and PVC bulkhead fittings in different sizes and with different gasket options. The fitting material and gasket material must be selected according to the application and the liquid being stored.

Our Tanks section also presents different plastic tank configurations for storage and transportation and the factors to consider when building an installation for the actual application.

EPDM and Viton replacement gaskets for bulkhead fittings

A leaking bulkhead fitting does not necessarily need to be replaced completely. Depending on the condition of the fitting and the cause of the leak, replacing only the gasket may restore the assembly.

Agrico Plastics offers EPDM and Viton replacement gaskets for different bulkhead fittings installed on plastic tanks.

The gasket located between the bulkhead fitting and the tank wall provides the seal. Over time, a gasket may become damaged, deformed or need replacement.

Fitting diameter alone is not enough to choose the gasket

This is probably the most important point to verify before ordering.

Do not select a gasket only because it is identified as 2", 3" or 4". The nominal diameter refers to the fitting connection, but different bulkhead fitting models of the same nominal diameter may use different gaskets.

Gaskets differ depending on whether they are used with standard threaded, heavy-duty or bolted bulkhead fittings. The corresponding gaskets are not necessarily interchangeable.

Identify the exact bulkhead fitting on which the gasket will be installed and confirm that the replacement gasket is compatible with that specific model.

EPDM or Viton: what is the difference for your fitting?

The choice between EPDM and Viton should not be based simply on the assumption that one material is “better” than the other. Compatibility with the stored product and with the fitting should determine the choice.

A leak does not automatically mean the gasket is defective

When a bulkhead fitting leaks, immediately replacing the gasket without inspecting the installation may not solve the problem.

The leak may be related to the condition of the gasket, the position of the fitting, the surface on which it is installed or the tightening of the assembly.

Overtightening is particularly important to avoid. Excessive tightening can compress or pinch the gasket and cause a leak instead of eliminating it. An overtightened fitting can also create stress on the tank wall, which may eventually crack.

When a bulkhead fitting must be tightened without a torque wrench, the manufacturer recommends hand-tightening the nut and then adding approximately 1/4 to 1/2 turn. Excessive tightening can affect gasket positioning and place unnecessary stress on the tank wall.

Before replacing the gasket, inspect the fitting

When a fitting is removed, take the opportunity to inspect the general condition of the components.

A new gasket will not necessarily correct a damaged fitting or an installation that no longer allows the gasket to seat properly against the tank wall.

Do not assume that a gasket from another fitting of the same nominal diameter will be compatible. The shape and dimensions of the gasket must correspond to the fitting for which it was designed.

If you do not know the bulkhead fitting model, a photo of the installed fitting, gasket and complete assembly can help identify the required replacement part.

Frequently asked questions

Can I replace only the gasket on my bulkhead fitting?

Yes. Replacement gaskets are available for several bulkhead fittings. However, verify that the fitting itself is in good condition and select the gasket designed for the exact fitting model.

Can I choose the gasket based only on the fitting diameter?

No. Nominal diameter is not always enough. Several bulkhead fitting models can exist in the same nominal diameter and may use different gaskets. Identify the fitting model before ordering.

What is the difference between an EPDM and a Viton gasket?

EPDM and Viton are different sealing materials with different chemical compatibility characteristics. Selection should be based on the stored liquid and the fitting being used, rather than simply preferring one material over the other.

Should I tighten a leaking bulkhead fitting more?

Not necessarily. Excessive tightening can pinch the gasket and cause a leak. First inspect the gasket, its position and the fitting installation before tightening further. Also verify that the fitting has been tightened in the proper direction. It should first be hand-tightened, then tightened slightly more than a quarter turn, without exceeding approximately one-half additional turn when no specific torque requirement is provided.

Can I replace an EPDM gasket with a Viton gasket?

Yes, but only if a compatible Viton gasket is available for the fitting model and the material is suitable for the liquid being used. The fitting diameter alone does not confirm compatibility.