US4472207A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for manufacturing blank material suitable for oil drilling non-magnetic stabilizer
Assignee: KOBE SEIKO SHO 3-18 WAKINOHAMA-CHO 1-CHOME CHUO-KU KOBE 651 JAPAN KK
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Filing: 1983-03-25
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Granted: 1984-09-18
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Expires: 2003-03-25
Abstract
Abstract A method of manufacturing a blank for an oil drilling stabilizer, which includes the steps of hot-working a stock of non-magnetic steel into a rod-like shape work item with a bulging large-diameter portion at a median point between opposite ends thereof; subjecting the resulting rod-like work item to an ordinary heat treatment solution and a machining operation to obtain a semi-finished work item of a shape substantially conforming with the desired shape; and then subjecting the semi-finished work item to cold axial compressive working in a die cavity of a complementary shape and within a work hardening temperature range.
Inventors
- 👤 Shushi Kinoshita
- 👤 Shinpei Denoh
- 👤 Yoshio Kitamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:01
CPC Classifications
E; E21; E21B; E21B17/00; E21B17/10; E21B17/1078; B; B23; B23P; B23P15/00; C; C21; C21D; C21D8/00; C21D8/06
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
101 words
A method of manufacturing a blank for an oil drilling stabilizer, which comprises: hot working a stock of non-magnetic steel into a rod-like work item form with a bulging large-diameter portion at a median point thereof and between opposite ends thereof; subjecting said rod-like work item to a solution heat treatment and a machining operation to obtain a semi-finished work item with a shape substantially conforming with a shape of a desired product; and subjecting said semi-finished work item to cold axial compressive working in a die cavity of a substantially complementary shape and within a predetermined work hardening temperature range.
Claim 2
Independent Claim
101 words
A method of manufacturing a blank for an oil drilling stabilizer, which comprises: hot working a stock of non-magnetic steel into a rod-like work item form with a bulging large-diameter portion at a median point thereof and between opposite ends thereof; subjecting said rod-like work item to a solution heat treatment and a machining operation to obtain a semi-finished work item with a shape substantially conforming with a shape of a desired product; and subjecting said semi-finished work item to cold axial compressive working in a die cavity of a substantially complementary shape and within a predetermined work hardening temperature range.
Claim 3
Dependent Claim
18 words
The method as set forth in claim 1, wherein said work hardening temperature range is below 350° C.
Claim 4
Dependent Claim
21 words
The method as set forth in claim 2, wherein said work hardening temperature range is from room temperature to 350° C.
Claim 5
Dependent Claim
18 words
A method as set forth in claim 3, wherein said work hardening temperature range is from 150°-350° C.
Claim 6
Dependent Claim
24 words
The method as set forth in claim 1, wherein said hot working step further comprises hot working at a heating temperature of 800°-1200° C.
Claim 7
Independent Claim
25 words
The method as set forth in claims 1 or 5, wherein said step of hot working further comprises hot working a rate greater than 30%.
Claim 8
Dependent Claim
40 words
The method as set forth in claim 1, wherein said step of subjecting said rod-like work item to said solution heat treatment further comprises subjecting said work item to a solution heat treatment within a temperature range is 1000°-1150° C.
Claim 9
Independent Claim
115 words
A method of manufacturing an oil drilling stabilizer, which comprises: hot-working a stock of non-magnetic steel into a rod-like work item form with a bulging large-diameter portion at a median point thereof and between opposite ends thereof; subjecting said rod-like work item to a solution heat treatment and a machining operation to obtain a semi-finished work item with a shape substantially conforming with a shape of a desired product; subjecting said semi-finished work item to cold axial compressive working in a die cavity of a substantially complementary shape and within a predetermined work hardening temperature range; subjecting said work item to stress relief annealing; and subsequently subjecting said work item to a finish machining operation.
Claim 10
Independent Claim
115 words
A method of manufacturing an oil drilling stabilizer, which comprises: hot-working a stock of non-magnetic steel into a rod-like work item form with a bulging large-diameter portion at a median point thereof and between opposite ends thereof; subjecting said rod-like work item to a solution heat treatment and a machining operation to obtain a semi-finished work item with a shape substantially conforming with a shape of a desired product; subjecting said semi-finished work item to cold axial compressive working in a die cavity of a substantially complementary shape and within a predetermined work hardening temperature range; subjecting said work item to stress relief annealing; and subsequently subjecting said work item to a finish machining operation.
Claim 11
Dependent Claim
27 words
The method as set forth in claim 8, wherein said step of stress relief annealing further comprises stress relief annealing at a temperature range of 200°-350° C.
Claim 12
Dependent Claim
26 words
The method as set forth in claim 8, wherein said step of cold axial compressive working further comprises compressive working a temperature range below 350° C.
Claim 13
Dependent Claim
31 words
The method as set forth in claim 10, wherein said step of cold axial compressive working further comprises compressive working at a temperature range of from room temperature to 350° C.
Claim 14
Dependent Claim
27 words
The method as set forth in claim 11, wherein said step of cold axial compressive working further comprises compressive working at a temperature range of 150°-350° C.
Claim 15
Dependent Claim
25 words
The method as set forth in claim 8, wherein said step of hot working further comprises hot working at a heating temperature of 800°-1200° C.
Claim 16
Independent Claim
26 words
The method as set forth in claims 8 or 13, wherein said step of hot working further comprises hot working a rate of greater than 30%.
Claim 17
Dependent Claim
40 words
The method as set forth in claim 8, wherein said step of subjecting said rodlike work item to said solution heat treatment further comprises subjecting said work item to a solution heat treatment within a temperature range of 1000°-1150° C.
Claim 18
Dependent Claim
30 words
The method as set forth in claim 1, wherein said blank for oil drilling stabilizer further comprises a blank having a 0.2% yield strength greater than 70 kg/mm 2 .
Claim 19
Dependent Claim
28 words
The method as set forth in claim 1, wherein said blank for oil drilling stabilizer further comprises a blank having a specific magnetic permeability of less than 1.01.
Claim 20
Dependent Claim
28 words
The method as set forth in claim 8, wherein said oil drilling stabilizer further comprises a blank having a 0.2% yield strength greater than 70 kg/mm 2 .
Claim 21
Dependent Claim
26 words
The method as set forth in claim 8, wherein said oil drilling stabilizer further comprises a stabilizer having a specific magnetic permeability of less than 1.01.
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) | 1987-09-18 | 1988-03-19 | 1988-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-18 | 1992-03-19 | 1992-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-18 | 1996-03-19 | 1996-09-18 | $7700.00 | Window Closed / Lapsed |