Valve Seat and Seat Ring Basics

Compressor valves come in an array of shapes and sizes, but all of them have one thing in common: the valve seat. And with the valve seat, there typically is a valve seat ring. Working in conjunction with each other, as well as with other parts of a valve, the seat and seat ring create an airtight environment that facilitates the proper function of a valve.


Valve Seat

The valve seat is a surface inside the body of a valve that comes into contact with the disk, which is a moveable component that restricts and allows flow through the valve. It has several important purposes, including the following:

  • Preventing compressed or combustion gasses from getting into the manifold.
  • Permitting a particular amount of heat to travel through the valve to the cylinder head.
  • Maintaining the proper seal of a mounted valve.
  • Reducing wear-resistance by resisting pressure and high heat.

Valve Seat Ring

The valve seat ring creates a shutoff surface. Typically held in place by pressure, a seat ring may also be threaded and screwed into the valve body. The seat ring is a crucial part for maintaining the strength of the seal within the valve and facilitating a seal that is free of leaks.

As crucial as they are, the valve seat and seat ring do not work alone. Other important compressor valve components include:

  • Gaskets –These aid in creating airtight seals within valves. These are especially useful for filling out imperfections in machined parts that would otherwise compromise the air tightness of the valve.
  • Springs – These facilitate rapid opening and closing of the valve to allow and restrict flow through the valve. Springs can be crafted from a variety of materials to accommodate different operating environments, including stainless steel, copper and others.
  • Valve plates – these, working in concert with other valve parts, regulate flow of air or fluid in a valve.


Periodic inspection of all compressor valve parts, including the seat and the ring, is recommended to ensure your machines remain in good working order.



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Industries we serve

Natural Gas Industry

The processing and refining of Natural Gas into a marketable products, by separating gas into pipeline-quality natural gas and a stream of mixed natural gas liquids and the transportation of natural gas to through a series of reciprocating compressor stations and pipes, and from there to end users.

Blow Molding Industry

This industry manufactures blow molding machinery. Injection stretch blow molding process has two main different methods, a single-stage and two-stage process; these are the methods by which hollow plastic parts are formed.

Medical Technology Industry

The medical technology industry is an important part of the healthcare sector. It includes most medical devices which aid the prevention, diagnosis and treatment of diseases and illnesses. Established centers of this industry include the United States and Western Europe.