an inner valve element an outer valve element spaced apart from the inner valve element a valve stem on which both the inner valve element and the outer valve element are located a portion of the valve stem between the inner valve element and the outer valve element is threaded and a protective element located within the valve housing and covering the threaded portion of the valve stem methods of using such valve assemblies are also disclosed application_number US 201514874705 A description fig1 shows a valve assembly 10 in cross section the valve assembly includes a valve body housing 12 an inlet opening 14 and an outlet opening 16 an inlet 18 portion of the valve body housing 12 is threaded to facilitate fastening the housing to a transfer pipe not shown carrying liquid to be passed through the valve assembly 10 the outlet portion 20 of the valve body housing 12 is threaded to facilitate fastening or securing the valve body housing to outlet elbow 22 which provides a pathway for liquid passing through the valve assembly 10 from the inlet opening 14 through the outlet opening 16 into space 24 and out of the elbow opening 26 the outlet elbow.