Frequently Asked Questions

How do you change the shear pin in a model FC Gate Valve?

We thought it best to answer this question with the attached PDF. The PDF Diagrams the process.

What is the most efficient way to heat up a valve that has frozen?

Most use a steam cleaner and spray the valve with the hot steam water until valve operates properly. It is also possible to inject the “artic thaw antifreeze” into the lower fitting until it comes out the top bleeder fitting. Only authorized capable service technicians should perform this task.

Why is my 7 1/16" valve harder to operate than others?

A full bore 7 1/16″ valve is a large bore valve with a large area of resistance. One man will be able to operate a manual unassisted valve, but it will be difficult and require a high torque. The valves vary from valve to valve and operation to operation, all depending on many factors aligning within the valve. All measures are taken to provide the easiest operating and durable valve possible. Ball screws are available to reduce the torque and number of turns required to open and close the valve.

While in service, why will my valve not fully open or close and not accomplish the full number of turns required to open and close the valve; but the turns will vary from point to point?

When there has been no physical damage to the valve or its internals, (with physical damage, usually the valve is locked up and will not turn at all, or the position is constant) it is very common that during operations and use of the valve where a media has flowed through the valve, freezing temperatures will be created within the valve causing any condensation to create freeze plugs to not allow the valve to open or close fully, and the number of turns accomplished will vary during operation and the ice thaws or moves. The valve is thawed quickest with the use of a steam cleaner to warm the valve.

When pressuring up my valve, why do I momentarily see moisture droplets from the body-bonnet-bonnet seal ring area?

After years of field service applications and inhouse controlled testing, it is determined that anytime a valve assemble becomes exposed to condensation or wet conditions such as weather, rain, test media water, etc; it is very common that once the valve is under pressure, droplets of moisture might escape from the bonnet – body bolted area once a higher pressure is obtained, giving the appearance that the valve may have a bonnet seal ring leak, where actually no loss of pressure or leak exist.

Does it matter which way you have the valve facing, due to pressure or flow?

Depends on the model of valve.

Directional: Yes
Model M, Expanding Gate

Bidirectional: No
Any Slab Gate, Model FC, Model MSG

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