Patent US4517506A successfully refreshed from Google Patents.
US3753464A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Arrangement for inhibiting the unthreading of casing string during well completions
Assignee: Individual
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Filing: 1971-07-07
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Granted: 1973-08-21
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Expires: 1991-07-07
Abstract
Abstract A plurality of sections of tubular members is arranged in endto-end relationship with couplings between the sections of tubular members for connecting them together. The sections of tubular members and couplings are provided with left-hand threads to inhibit the unthreading of the tubular sections during well completions. The casing string may include so-called auxiliary equipment for aiding in floating it into position in the well bore and guide equipment which is also provided left-hand threads.
Inventors
- 👤 B Wilhelm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 15:45
CPC Classifications
E; E21; E21B; E21B17/00; E21B17/02; E21B17/08; E21B17/14; E21B21/00; E21B21/10
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
66 words
An arrangement for inhibiting the unthreading of casing string including: a. a plurality sections section of tubular members in end-to-end relationship to form a casing string for a well; b. coupling means for engaging the ends of adjacent tubular members together; and c. said sections and coupling means each having left-hand threads for engaging the couplings and sections together to maintain said sections in end-to-end relationship.
Claim 2
Dependent Claim
66 words
An arrangement for inhibiting the unthreading of casing string including: a. a plurality sections section of tubular members in end-to-end relationship to form a casing string for a well; b. coupling means for engaging the ends of adjacent tubular members together; and c. said sections and coupling means each having left-hand threads for engaging the couplings and sections together to maintain said sections in end-to-end relationship.
Claim 3
Dependent Claim
39 words
The invention of claim 1 wherein the casing string incorporates a float collar and a guide shoe for guiding the casing string into the well and wherein the guide shoe is connected to the casing string with left-hand threads.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-20 | 1977-02-19 | 1977-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-20 | 1981-02-19 | 1981-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-20 | 1985-02-19 | 1985-08-21 | $7700.00 | Window Closed / Lapsed |