GATE VALVE HAVING LOW-FRICTION COATING OVER SUBSTRATE AND METHOD FOR MAKING SAME

摘要

A gate valve has a body, the body having a cavity and a flow passage intersecting the cavity. A seat fabricated from a ceramic and/or hardfacing alloy matrix composite substrate is mounted to the body at the intersection of the flow passage and the cavity. A gate fabricated from a ceramic and/or hardfacing alloy matrix composite substrate is installed at the cavity and has an engaging face that slidingly engages the seat while the gate is being moved between open and closed positions. The engaging faces of the gate and seats are coated with a low-friction material to facilitate sliding. The ceramic and/or hardfacing alloy matrix composite substrate construction of the gate and seats with low friction engaging surfaces enhances the gate valve's bearing stress capacity.