| 摘要 |
A downhole well tool, such as a subsurface safety valve, has a two part body 36, 38 which is assembled to form an annular chamber 10 to which hydraulic control fluid is supplied from the surface via port 16 to control the valve. The chamber 10 is formed with a thin internal wall which can be easily penetrated so that control fluid can be supplied to a replacement valve landed in the tool. |
