Pig trap closure
US4237936A · kind A · utility
22Cited by
7References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 30, 1978 |
| Grant date | Dec 9, 1980 |
| Priority date | — |
| Expiry date | May 30, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01M3/005
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A pig trap closure is disclosed which includes a collar adapted to be attached to the end of a pipe, a door for opening and closing the end of the pipe, means for clamping the door to the collar and sealing means for preventing communication between the interior of the pipe and the atmosphere when the door is clamped to the collar. A testing valve is provided for indicating the presence of pressurized fluid in the pipe and means connects the testing valve to a handle used to unclamp the door for preventing movement of the handle until after the presence of pressurized fluid within the pipe has been checked by the testing valve.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.