API 6D Handwheel Expanding Through Conduit Gate Valve
Design standardAPI 6D ASME B16.34
Structual lengthFlanged endsAPI 6D ASME B16.10
Flanged endsASME B16.5 MSS SP44
Butt-welding endsASME B16.25
Test &inspectionAPI 6D API598
1. With equal pressure throughout the valve(and the gate in closed position), and initial seal is formed with the raised PTFE ring on the faces of the seats. (The seat-inserts clean both sides of the gate each time the valve is opened or closed)
2. As line pressure is applied to the valve. It acts on the gate, forcing it against the PTFE ring on the downstream seat, compressing it until the seat against the steel seat. Thus, a double seal is formed...First, a PTFE-to-metal seal; Then, metal-to-metal. The seat is also forced firmly into its recess. The O-ring prevents any downstream flow at this point.
3. Upstream seal is provided when valve cavity pressure is bled off. This is caused by the force of line pressure acting against the upstream seat moving the seat against the gate and providing a tight PTFE-to metal seal at this point. At the same time. The O-ring forms a tight seal with the seal recess.
4. Valve automatically relieves itself of excessive valve cavity pressure. When valve cavity pressure exceeds line pressure...From such causes as thermal expansion...The upstream seat is forced back into its recess and the excess pressure in the valve cavity is bled between the seat and the gate into the line.
|Ordinary type||Antisulphur type|
Contact us if you need more details on Through Conduit Gate Valve. We are ready to answer your questions on packaging, logistics, certification or any other aspects about Gate Valve、Api Gate Valve. If these products fail to match your need, please contact us and we would like to provide relevant information.
Product Categories : Slab Gate Valve