| US 7,467,676 B2 | ||
| Method and device for preventing pipeskidding | ||
| Tor Egil Mong, Vigrestad (Norway); and Tommy Johnsen, Hafrsfjord (Norway) | ||
| Assigned to Malm Orstad AS, Voll (Norway); and Kokstad Invest AS, Bergen (Norway) | ||
| Filed on Dec. 18, 2007, as Appl. No. 11/958,909. | ||
| Application 11/958909 is a continuation of application No. 10/498276, granted, now 7,337,861, previously published as PCT/NO02/00454, filed on Nov. 29, 2002. | ||
| Claims priority of application No. 20015913 (NO), filed on Dec. 03, 2001. | ||
| Prior Publication US 2008/0093091 A1, Apr. 24, 2008 | ||
| Int. Cl. E21B 18/06 (2006.01) | ||
| U.S. Cl. 175—423 [248/49; 248/65; 166/77.4; 166/77.52] | 9 Claims |
| 1. A method of preventing a pipe string clampingly arranged in a slips from slipping out of said slips in the event of said
pipe string slipping in said slips, said method comprising the steps of:
a) connecting a pipe clamp to a slips manipulator, said slips manipulator having an arm frame;
b) connecting said arm frame to said slips;
c) hydraulically clamping said pipe clamp to said pipe string at a position above said slips, such that said pipe string does
not move relative to said pipe clamp;
d) in the event of said pipe string slipping in said slips, said arm frame allowing said clamp together to displace downward
with said pipe string until said pipe clamp stops in said slips.
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