Circulating pump

Abstract

A circulating pump having a pump housing made of non-metallic materials, such as plastic, composite or other moldable materials. The use of a non-metallic housing facilitates the use of features which are difficult or expensive to obtain with a metal cast housing. A U-bolt or other clamping member couples the pump housing between the pump motor and a metallic tubular manifold to place the housing in compression between the motor and manifold to virtually eliminate tensile and bending stresses in the pump housing and, thereby, reduce the possibility of structural degradation from exposure of the non-metallic housing to fluids. The manifold has a shaped portion having a planar surface thereon that abuts the housing and provides a surface for one or more sealing members between the manifold and the housing. The metallic manifold allows the circulating pump to be installed in a metallic piping system utilizing conventional installation materials and methods. A check valve can be installed in the housing to eliminate the need for multiple connections and in a manner that allows the check valve to be field serviceable without removing the pump from the piping system. A method for making the tubular manifold is also presented.