Gate valve

The gate valve with a flanged connection is the main closing device of wellheads and christmas trees. The main valve is manually operated: it can be closed by rotating the handwheel clockwise. The gate valve has a full opening bore. The gate valve has a parallel, unvided vertical spindle type closing surface. The spindle and the spindle nut moving the closing plate are situated within the housing. The part of the vertical spindle above the closing plate has a conical shape and it ensures metallic packing by fitting into the conical part of the top cap. When not under pressure, the seat rings are preloaded by a rubber spring. A special PTFE ring pressed into the seat ring ensures the packing between the seat ring and the closing plate. One line pressure increases the preloading of the seat ring, thus promoting the closing towards the housing`s opening. If the packing box is damaged, it can be replaced without the removal of the gate valve.