04898244 is referenced by 28 patents and cites 5 patents.

A downhole pump and perforating gun are run simultaneously down a well on a tubing string and the gun is fired under underbalanced conditions. A slip joint reduces vertical mechanical shock transmitted through the tubing string to the pump on firing; centralizers minimize whiplash vibration and a lateral shock absorber absorbs radial shock.

Title
Installation of downhole pumps in wells
Application Number
7/235891
Publication Number
4898244
Application Date
August 12, 1988
Publication Date
February 6, 1990
Inventor
Hugo M Barcia
18 Bremen Drive, West Hill, Skene, Aberdeenshire
GB
John L Schneider
Beech Wood Place, West Hill, Skene, Aberdeenshire
GB
Agent
Florence U Reynolds
IPC
E21B 43/00
E21B 43/116
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