This type of valve is in almost universal use at present.

Spring force is sometimes used to recover the position of valve.

"You mean a type of valve which would allow gas to be introduced into the line?"

With a prayer, he opened a second set of valves.

The pressure created by the spring acts on the opening of the valve.

However, two important facts were established by the use of such valves.

A blow rocked him, and he shot back against the side of the valve.

It is a well-known production base of water film and valves.

Sadly today, the making of valves is a dying art.

To her right was a series of valves, dominated by another huge wheel on the wall.