Patent · US Expired

Double acting shock absorbers for drill strings

US4194582A · kind A · utility

32Cited by
5References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 28, 1978
Grant dateMar 25, 1980
Priority date
Expiry dateJun 28, 1998

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B17/07
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A telescopic shock absorber for incorporation in a drill string connected to a rotary bit for drilling a bore hole in earth formations, the shock absorber including a single spring assembly which is compressed downwardly when sufficient downwardly directed drilling weight is transmitted from the drill string through the shock absorber to the drill bit, and which is compressed upwardly when the internal drilling fluid pressure in the shock absorber fully overcomes the downwardly directed drilling weight, assuring that the spring assembly is in its compressed condition when the shock absorber is telescoped or extended, enabling it to absorb shocks and vibrations incident to the drilling operation and under both conditions.

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