Crown block dead line anchor
OwnerWalter Welshinventor
Life of this patent
Estimating the term…
Abstract
The line system on a drilling rig is arranged to place the dead line clamp at the upper end of the derrick. A dead line anchor sheave is preferably located to accept wraps of the dead line to insure reduced load on the dead line clamp. The anchor sheave is preferably lockable to prevent rotation and releasable to rotate the anchor sheave for line feeding from a reserve line reel for maintenance operation. A load sensor is optionally provided to sense dead line load for sensing associated hook loads on the traveling block. An motor is provided, as an option, to rotate the anchor sheave for line feeding maintenance operations.
Claims17
A dead line load reducing apparatus comprising:
- a) a drilling rig derrick with a crown block, traveling block, draw works, and a line system extending from a reserve reel, through a dead line clamp to the crown block, reeved about the sheaves of sheave cluster of the crown block and traveling block and from the crown block to a line drum on the draw works;
- b) an anchor sheave on the crown block, on an axle carrying the crown sheave cluster, to accept at least two turns of the dead line;
- and
- c) a dead line clamp on structure supporting the crown block situated to receive the line extending from the anchor sheave to the reserve reel.
A dead line load reducing apparatus comprising:
- a) a drilling rig derrick with a crown block, traveling block, draw works, and a line system extending from a reserve line reel, through a dead line clamp to the crown block, reeved about the sheaves of the crown block and traveling block and from the crown block to a line drum on the draw works;
- b) an anchor sheave situated near the crown block, to accept at least two turns of the dead line;
- and
- c) a dead line clamp, on structure supporting the crown block, situated to receive the line extending from the anchor sheave to the reserve reel.
A dead line load reducing apparatus comprising:
- a) a drilling rig derrick with a crown block, traveling block, draw works, and a line system extending from a reserve reel, through a dead line clamp to the crown block, reeved about the sheaves of sheave cluster of the crown block and traveling block and from the crown block to a line drum on the draw works;
- and
- b) an anchor sheave on the crown block to accept at least two wraps of the dead line.
Dependencies are inferred from the claim text.