Well casing grip assurance system

• US 4,676,312 A
• Filed: 12/04/1986
• Issued: 06/30/1987
• Est. Priority Date: 12/04/1986
• Status: Expired due to Term

• Current Assignee: Frank's Casing Crew and Rental Tools Incorporated (Frank's International N.V.)
• Original Assignee: Donald E. Mosing
• Inventors: Mosing, Donald E., Webre, Charles M.
• Primary Examiner(s): Novosad, Stephen J.
• Assistant Examiner(s): Letchford, John F.
• Application Number:
  US06/937,894
• Time in Patent Office: 208 Days
• Field of Search: 166/77, 166/381, 166/385, 175/162, 175/203, 254/29 R, 254/29 A, 254/30, 254/31, 173/149
• US Class Current: 166/77.53
• CPC Class Codes: E21B 19/07 Slip-type elevators

Abstract

A casing grip assurance interlock system connected with the elevator and the spider of a well casing installation apparatus including positioning valves respectively actuated by the elevator and the spider to permit actuating fluid pressure to be admitted to either the elevator or the spider only when the other of the elevator or spider is positioned to firmly grip the well casing.

Claims

1. In apparatus for assuring that at least one of the elevator or the spider of well casing installation apparatus is fully closed in gripping connection about a well casing before the other of said elevator or said spider may be released from fully closed gripping connection about said well casing, the continuation comprising:

(a) two-position elevator valve means connected to admit fluid pressure into said elevator and to optionally direct said fluid pressure to open and to close said elevator;

(b) two-position spider valve means connected to admit fluid pressure into said spider and to optionally direct said fluid pressure to open and to close said spider;

(c) two-position spider position valve means connected to said elevator valve means, said spider position valve means being mechanically connected to said spider for passing said fluid pressure to said elevator valve means only when said spider is fully closed into gripping position; and

(d) two-position elevator position valve means connected to said spider valve means, said elevator position valve means being mechanically connected to said elevator for passing fluid pressure to said spider valve means only when said elevator is fully closed into gripping position.

2. The combination of claim 1 wherein said fluid pressure is air pressure.

3. The combination of claim 1 wherein said fluid pressure is hydraulic pressure.

4. The combination of claim 1 wherein all said valve means are electrically actuated by electrical solenoids with said position valve means being mechanically connected with electrical limit switch means.

5. In apparatus for installing casing in a well bore including a drilling rig having a traveling block and a supportive rig floor, a casing gripping fluid actuated casing elevator assembly carried by the traveling block and a casing gripping fluid actuated casing spider assembly mounted on the rig floor, the elevator assembly and the spider assembly each having a piston in a pressurable closing chamber to actuate slips into gripping engagement with casing when the closing chamber is pressurized, and a pressurable opening chamber also containing a piston to move the slips into release from the casing when the opening chamber is pressurized, the improvement of casing grip control apparatus for assuring correct and appropriate gripping of the elevator assembly and the spider assembly onto well casing comprising:

(a) a first two-position control valve respectively connected into the closing chamber and the opening chamber of said elevator assembly;

(b) a second two-position control valve respectively connected into the closing chamber and the opening chamber of said spider assembly;

(c) each said first and said second control valves being optionally actuated to admit fluid pressure alternately into a closing chamber and an opening chamber while venting the other chamber to atmosphere;

(d) a third two-position control valve connected to be in a first open position when said spider is in fully closed gripping position and in a second closed position when said spider is other than fully closed;

(e) a forth two-position control valve means connected to be in a first open position when said elevator is in fully closed gripping position and a second closed position when said elevator is other than fully closed;

(f) said third control valve being connected to pass fluid pressure from a pressure source to said first control valve only when said third control valve is in first open position; and

(g) said fourth control valve connected to pass fluid pressure from a pressure source to said second control valve only when said fourth control valve is in first open position.

6. The combination of claim 5 wherein said fluid pressure is air pressure.

7. The combination of claim 6 wherein all said valve means are electrically actuated by electrical solenoids with said position valve means being mechanically connected with electrical limit switch means.

8. The combination of claim 5 wherein said fluid pressure is hydraulic pressure.

9. The combination of claim 8 wherein all said valve means are electrically actuated by electrical solenoids with said position valve means being mechanically connected with electrical limit switch means.

10. In a method of assuring at least one of the elevator or the spider of well casing installation apparatus is fully closed in gripping connection about a well casing before the other of said elevator or said spider may be released from said fully closed gripping connection about said well casing, the steps comprising:

(a) supplying fluid pressure to a two-position elevator valve connected to admit fluid pressure into said elevator and optionally directing said fluid pressure to open and to close said elevator;

(b) supplying fluid pressure to a two-position spider valve connected to admit fluid pressure into said spider and to optionally direct said fluid pressure to open and to close said spider;

(c) passing fluid pressure from a two-position spider position valve to said elevator valve, said spider position valve being mechanically connected to said spider for passing said fluid pressure to said elevator valve only when said spider is fully closed into gripping position; and

(d) passing fluid pressure from a two-position elevator position valve to said spider valve, said elevator position valve being mechanically connected to said elevator for passing fluid pressure to said spider valve only when said elevator valve is fully closed into gripping position.

11. The method of claim 10 wherein said fluid pressure is air pressure.

12. The method of claim 10 wherein said fluid pressure is hydraulic pressure.