Gate valve with lock ring

摘要

A packingless gate valve is disclosed which includes a housing having opposed similar housing halves with pipe nipples extending therefrom and with resilient sleeve units installed on respective lock rings mounted in recessed portions of the housing halves. The sleeves act to compressibly engage each other in the valve open condition and engage opposite sides of the gate in the valve closed condition. Each sleeve unit has a radially outwardly extending flange on the inner and outer axial ends with these flanges being located in indented regions between each lock ring and the respective housing half. An encircling thin stiffening ring of harder material is bonded to the axially outer surface of the flange on the inner end of each sleeve, each stiffening ring being shaped with a right angle bend so as to provide both axially and radially facing surfaces for each sleeve body. Each stiffening ring is engaged with the respective lock ring along the entire length of the stiffening ring. The particular configuration and position of the sleeve units with the lock rings and stiffening rings has been found to function advantageously in maintaining proper operation of the gate valve. The gate valve construction of the present invention results in no leakage to the outside when the valve is fully open and no leakage to the outside or past the gate internally when the valve is fully closed.