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FKI Safety Valves Contribution on Various Fields

Fukui Seisakusho Safety Valve

Fukui Seiakusho Safety Valve

Since its inception in 1936, Fukui Seisakusho has been dedicated to meeting a wide variety of market needs and has supported the world's manufacturing industries as one of the leading manufacturers of safety valves.


Fukui Seisakusho , as a company participating in " Security ", contributes its best efforts to manufacturing without any commitment.
Innovation continues and reliability turns out to be the main strength of Fukui ( FKI ).

Classification of Safety Valves

There are Three Types of Safety Valves in the FUKUI Production Line.

Spring loaded pressure relief valves

Fukui Seiakusho Safety Valve

Spring-loaded Pressure-relief Valves

In general, these safety valves refer to spring loaded pressure relief valves , it is the most common type (see figure to the left).


The spring load is designed to press the " Disc " against the inlet pressure.

Depending on the type of fluid, such as steam, gas or liquid, Fukui offers a bellows model to eliminate the back pressure effect.

Pilot Operated Pressure Relief Valves

Fukui Seiakusho Safety Valve

Pilot-operated Pressure-relief Valves

Pilot operated pressure relief valves are comprised of a fitted pilot and main valve. Although spring loaded pressure relief valves adopt spring force against inlet pressure, reactivation pressure and reset pressure of pilot operated pressure relief valves are controlled by Pilot Equipped which acts almost the same as spring loaded pressure relief valves. There is no adjustment function on the main valve.

Pilot operated pressure relief valves have greater size variations compared to the spring type used in severe conditions such as high pressure.

Deadweight Pressure Relief Valves

Fukui Seiakusho Safety Valve

Dead-Weight Pressure-relief Valves

In case the design pressure of the vessel is set to very low pressure, the deadweight pressure relief valve adjusts the relief pressure only by the weight of the disc.


The vacuum relief valve has adopted this functional feature that absorbs the pressure when the inside of the pressure vessel falls into a negative pressure.

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