| 摘要 |
1297297 Shearing PIPE-LINE DEVELOPMENT CO 30 Nov 1970 [24 Feb 1970] 56685/70 Heading B3W [Also in Division F2] Apparatus for opening a pipe-line comprises a fluid tight housing 11 for securing to the exterior of a pipe 12, a shearing tool 13 mounted in the housing and supported for movement radially of the pipe and externally operable actuator means for forcing the shear tool 13 through the wall of the pipe. As shown the housing 11 (in two halves) is secured to the pipe 12 by welding, the pipe having first been reinforced by welding thereto, rings 31, 32 in the vicinity of where the shearing is to take place. Actuating means in the form of double acting piston 63 in cylinder 14 and having the shear 13 attached thereto is then secured to the housing 11. The shear 13 has two cutting edges 47, 48 and by admitting fluid under pressure above piston 63 the shear 13 is forced downwards to shear away a portion of the pipe between rings 31, 32 depositing the sheared away portion in the lower half of housing 11 from where it can be subsequently removed. The shear 13 preferably houses a plug 15 which can be forced by fluid pressure admitted behind it into contact with one of the sheared faces of the pipe. Two such plugs may be provided if desired. Subsequently the plug and shear tool can be removed leaving the water tight housing in situ. The pipe can be initially weakened at the shear faces e.g. by cutting partially into the pipe surface and the water tightness of the housing 11 can be tested before the shearing operation by drilling a hole in the portion of pipe to be sheared away. |
