US3746329A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Piston type shock absorbing and static load supporting drill string apparatus
Assignee: LYNX TOOL COMPANY Inc A TEXAS CORP
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Filing: 1971-11-05
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Granted: 1973-07-17
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Expires: 1991-11-05
Abstract
Abstract Apparatus is disclosed for use in a drill string during rotary well drilling for supporting the static loads and for absorbing the shock loading imposed upon a drill bit. An improved separation element in the form of solid piston prevents migration of a shock absorbing gas into a liquid contained in the apparatus. The piston configuration and its annular seal arrangement solve a previously experienced gas migration problem. As a consequence, gas molecules are effectively excluded from regions where they otherwise interfere with normal operation of any components of the apparatus.
Inventors
- 👤 E Galle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:14
CPC Classifications
F; F16; F16F; F16F9/00; F16F9/06; F16F9/066; F16F9/067; E; E21; E21B; E21B17/00; E21B17/02; E21B17/04; E21B17/07
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
140 words
Improved shock absorbing and static load supporting apparatus for use in a drill string, said apparatus comprising: a tubular body adapted to be secured to a drill string member; a mandrel reciprocably mounted to the tubular body for rotation therewith, and having an end portion adapted to be secured to another drill string member; the body and mandrel having passage means for a drilling fluid; a gas and liquid cavity formed between the body and the mandrel with the body forming one end of said cavity and the mandrel forming the other end of said cavity; an improved separation means dividing said cavity into gas and liquid regions; valve means connected with said gas region for the introduction of a pressurized gas; said separation means comprising a fluid impervious floating piston that equalizes pressure between the gas and liquid regions.
Claim 2
Dependent Claim
140 words
Improved shock absorbing and static load supporting apparatus for use in a drill string, said apparatus comprising: a tubular body adapted to be secured to a drill string member; a mandrel reciprocably mounted to the tubular body for rotation therewith, and having an end portion adapted to be secured to another drill string member; the body and mandrel having passage means for a drilling fluid; a gas and liquid cavity formed between the body and the mandrel with the body forming one end of said cavity and the mandrel forming the other end of said cavity; an improved separation means dividing said cavity into gas and liquid regions; valve means connected with said gas region for the introduction of a pressurized gas; said separation means comprising a fluid impervious floating piston that equalizes pressure between the gas and liquid regions.
Claim 3
Dependent Claim
24 words
The apparatus defined by claim 1 in which the piston is annular, with sealing rings extending therefrom to opposed cylindrical surfaces in said body.
Claim 4
Dependent Claim
18 words
The apparatus defined by claim 2 wherein said piston is a metal and said sealing elements are resilient.
Claim 5
Dependent Claim
58 words
The apparatus defined by claim 2 wherein said piston comprises an enlarged annular region connected with an elongated region, the enlarged region having interior and exterior annular grooves containing resilient sealing rings, the elongated region having an annular groove facing a mating surface of the body, with a resilient ring therein, and passage means through the elongated region.
Claim 6
Dependent Claim
25 words
The apparatus defined by claim 4 wherein backup rings are disposed in the grooves beside the sealing rings in the enlarged region of the piston.
Claim 7
Dependent Claim
30 words
The apparatus defined by claim 2 which further comprises vent means to transmit the hydrostatic pressure of the drilling fluid in a well bore to the fluids in said cavity.
Claim 8
Dependent Claim
34 words
The apparatus defined by claim 6 which further comprises a separator and pressure means connected with said vent means to prevent drilling fluid from reaching said liquid region of the gas and liquid cavity.
Claim 9
Dependent Claim
51 words
The apparatus defined by claim 3 wherein a retainer ring is secured in said body beneath said piston, said ring having on one side an annular groove facing said piston with apertures extending from said groove through said piston, and said piston having an annular protrusion to mate with said groove.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-16 | 1977-01-15 | 1977-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-16 | 1981-01-15 | 1981-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-16 | 1985-01-15 | 1985-07-17 | $7700.00 | Window Closed / Lapsed |