Downhole tool utilizing well fluid compression

Patent · Tue May 20 04:00:00 EDT 1986

OSTI ID:5475447

Wray, G Q

A method is described of operating a downhole tool string, the method comprising the steps of: (a) providing in the tool string an operating element, a power piston operatively associated with the operating element, and upper and lower longitudinally spaced packer means; (b) lowering the tool string into a well bore; (c) sealing the upper and lower packer means between the tool string and the well bore, and thereby defining a sealed well annulus zone between the upper and lower packer means; (d) communicating a lower pressure side of the power piston means with the sealed well annulus zone through a compression passage; (e) applying an actuating pressure to a high pressure side of the power piston means; (f) moving the power piston means in response to a difference between the actuating pressure and well fluid pressure within the sealed well annulus zone, and thereby operating the operating element; (g) compressing well fluid within the sealed well annulus zone as the power piston means is moved to operate the operating element and thereby storing in fluid compression a portion of the energy applied to move the power piston means; (h) subsequently decreasing a pressure applied to the high pressure side of the power piston means; and (i) expanding the compressed well fluid in the sealed well annulus zone, and thereby returning the power piston to an original position thereof.

• Assignee: Halliburton Co., Duncan, OK
• Patent Number(s): US 4589485
• OSTI ID: 5475447
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
03 NATURAL GAS
030300 -- Natural Gas-- Drilling
Production
& Processing
42 ENGINEERING
420206 -- Engineering-- Mining & Drilling Equipment & Facilities-- (1980-1989)
COMPRESSION
CONTROL
CONTROL EQUIPMENT
DRILL PIPES
DRILLING EQUIPMENT
DRILLING FLUIDS
EQUIPMENT
EXPANSION
FLUIDS
HOISTING
HYDRAULIC CONTROL DEVICES
MATERIALS HANDLING
NATURAL GAS WELLS
OIL WELLS
OPERATION
PACKINGS
PIPES
PISTONS
PRESSURE CONTROL
SEALS
WELLS