Tubular plastic hydrant

Abstract

In a hydrant assembly, the combination comprising an outer tubular member having a first flow port; an inner tubular member having a closure thereon to close the port in relative axially advanced position of the closure, and to open the port in relative axially retracted position of the closure that allows fluid flow through the port to an outlet, control means to control relative movement of the inner and outer members. The closure means may include a bullet, an O-ring or the like carried by said bullet, the bullet telescopically carried by said inner member. A bore carried by the outer tubular member is in sliding sealing relationship to said O-ring. Once hydrant is closed (off position) the bullet will continue to advance into the bore as pressure in the outer tubular member increases when residual water freezes. Because of advancement of the bullet, pressure in the outer tubular member will never exceed supply line pressure thus preventing damage to the outer tubular member. A second port may be located sidewardly of the outer tubular member to pass fluid in relatively advanced position of the closure to relieve fluid pressure in space formed between the inner and outer members, the inner member being elongated and extending lengthwise in the outer tubular member. Since the pressure in the outer tubular member never exceeds the supply pressure, the outer tubular member can be made of plastic to reduce costs.