Patent · US Expired

Hydraulic catworks system

US4253354A · kind A · utility

2Cited by
4References
9Claims
0Family size

Inventor

Key dates

Filing dateSep 12, 1979
Grant dateMar 3, 1981
Priority date
Expiry dateSep 12, 1999

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B19/162
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A hydraulic catworks system for use on a well drilling rig for making up and breaking out a drill string which includes a hydraulic makeup piston and cylinder assembly for actuating a makeup line connected to the makeup tongs, and a breakout piston and cylinder assembly connected to a breakout line for actuating the breakout tongs. A makeup hydraulic control valve controls hydraulic fluid to first and second lines connected to the makeup assembly with the first line connected for extending the makeup line and the second line connected for retracting the makeup line. A breakout hydraulic control valve controls fluid to third and fourth lines with the third line connected for extending the breakout line and the fourth line connected for retracting the breakout line. Manual air control means are provided for selectively actuating the makeup and breakout control valves. A variable pressure control is connected to the second line for controlling the makeup torque. Preferably, the makeup and breakout assemblies are vertically connected to the legs of the drilling rig and rollers are positioned horizontally with the makeup and breakout tongs and connected to the breakout and makeup lines.…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.