Portable workover rig with extendable mast substructure, platform mounted drawworks and adjustable wellhead anchor

Patent · Tue Sep 22 04:00:00 EDT 1981

OSTI ID:5865960

Elliston, T L

A portable workover rig for handling a pipe string in a well casing includes a base platform and a collapsible mast which is movable from a reclining transport position to an erect elevated position of use. The mast is supported for free-standing operation by a carriage assembly including a cantilever support base mounted on the base platform for pivotal movement from the transport position to the position of use. The carriage assembly includes lift arms coupled in parallel relation intermediate the cantilever support base and the rig support platform for maintaining the cantilever support base in parallel alignment with the base platform. Hoisting and snubbing operations are performed by drawworks including a linear hydraulic actuator carried on the base platform, a traveling block supported for vertical movement along the mast by hoist and snub cables, and traveling sheaves carried by the actuator through a stroke pathway which is oriented transversely with respect to the mast. A vertically adjustable stack assembly is provided for accommodating the varying elevations of existing wellhead flange connections and for anchoring the rig platform to the wellhead casing. A powered drill sub assembly includes upstanding stab receptacles anchored to the top side of the traveling block and stab elements supported for vertical reciprocal movement between retracted and extended positions to permit displacement of the power sub relative to the traveling block during makeup and breakout operations.

• Assignee: Hydra Rig Inc
• Patent Number(s): US 4290495
• OSTI ID: 5865960
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
03 NATURAL GAS
030200 -- Natural Gas-- Reserves
Geology
& Exploration
42 ENGINEERING
420206 -- Engineering-- Mining & Drilling Equipment & Facilities-- (1980-1989)
ANCHORS
BOREHOLES
CAVITIES
DESIGN
DRILL PIPES
DRILLING EQUIPMENT
DRILLING RIGS
EQUIPMENT
MECHANICAL STRUCTURES
PIPES
SUPPORTS
TRANSPORT
WELLHEADS
WELLS