3799182 is referenced by 39 patents and cites 5 patents.

The invention comprises an add-on valve which includes, generally, a holding chamber which is adapted to be fixedly secured to a pipe, a gate valve assembly which is adapted to be removably affixed to the holding chamber, a saw chamber assembly including a saw for sawing an opening into the pipe, a pipe plug assembly including a closure which is operable to block the flow of fluid in the pipe, an insertion chamber assembly for inserting the pipe plug assembly into the holding chamber, and a completion bonnet for completing the assembly of the add-on valve.

Title
Add-on stopper valve for existing piping
Application Number
05/248,660
Publication Number
3799182
Application Date
April 28, 1972
Publication Date
March 26, 1974
Inventor
Long George M
Agent
Dominik Knechtel Godula & Demeur
Assignee
Institute of Gas Technology
IPC
F16e 41/04
B23b 41/08
F16L 41/04
F16L 41/00
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