摘要 |
A gate valve having a body made in two parts, namely a main part having flow passages and at least one body extension that accommodates movement of the gate between open and closed positions. The extension is generally rectangular as viewed from one end of the valve, and has outwardly bulged end walls as viewed from one side of the valve. The end walls are concave as viewed from the inside of the body. Also a method of manufacturing such a valve involving fabrication of a box-like structure with welding applied in a particular manner, after which hydraulic pressure is applied internally to pressure form the end walls of the structure to the desired configuration. |