Hydraulic shock absorber with nitrogen stabilizer
US5133419A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 16, 1991 |
| Grant date | Jul 28, 1992 |
| Priority date | — |
| Expiry date | Jan 16, 2011 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16F9/36
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A shock absorber device for inclusion in a tool string to provide rapid shock dissipation for shock forces traveling up or down the string. The device includes a tubular mandrel and an outer casing that forms an annular chamber therearound. At least one annular piston and one or more metering sleeves are formed integral with the outer casing and function to divide the annular chamber into a plurality of annular chambers that are filled with either nitrogen gas or silicone oil under selected pressures. Thus, the mandrel supports the lower tool string resiliently due to the fluid supported annular pistons such that any shock wave traveling along the tool string will be rapidly dissipated at the fluid piston interfaces.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.