Claims
- 1. A plug release plunger for a plug container connected to a well, comprising:
- a body having a first cavity, a second cavity and a channel communicating with said first and second cavities;
- a mandrel connected to said body and including means for connecting to the plug container;
- a retaining arm slidably disposed through said body, including said first cavity thereof, and said mandrel;
- a locking dog disposed in said first cavity adjacent said retaining arm and said mandrel;
- a support sleeve disposed in said first cavity so that said support sleeve longitudinally retains said locking dog adjacent said mandrel;
- a first piston disposed in said second cavity for radially fixing said locking dog within said first cavity to lock said retaining arm in extended position when said first piston is in a first position radially outwardly of said locking dog and for radially freeing said locking dog to unlock said retaining arm for moving to a retracted position when said first piston is in a second position;
- a spring disposed in said second cavity coaxially about said support sleeve for biasing said first piston towards said first position;
- a second piston disposed in said second cavity coaxially about said support sleeve for compressing said spring in response to pressure exerted on said second piston through said channel so that said second piston acts solely to insure that said first piston holds said locking dog in position locking said retaining arm in extended position; and
- handle means, connected to said first piston and extending through and outside said body, for manually moving said first piston to said second position, and wherein said body further includes a port for communicating fluid pressure to move said first piston to said second position, so that said first piston is moved to said second position by either manual or fluid pressure actuation.
Parent Case Info
This is a divisional of copending application Ser. No. 07/516,638 filed on Apr. 30, 1990.
US Referenced Citations (16)
Foreign Referenced Citations (3)
Number |
Date |
Country |
896839 |
May 1944 |
FRX |
0001284 |
Jan 1977 |
JPX |
421807 |
Aug 1974 |
SUX |
Non-Patent Literature Citations (3)
Entry |
LaFleur Petroleum Services brochure which begins "Now . . . a Safe, Sure and Proven Cementing Head that Permits Positive Plug Drop with Continuous Cement Flow", believed to be published more than one year prior to Apr. 27, 1990. |
LaFleur Petroleum Services brochure with front page containing the word "FASDROP", believed to be published more than one year prior to Apr. 27, 1990. |
Halliburton Company Technical Data Sheet C-1152, "Remote Control For Release of Cementing Plug", dated Nov., 1965. |
Divisions (1)
|
Number |
Date |
Country |
Parent |
516638 |
Apr 1990 |
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