US4093839A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus and method for inductively heating metallic tubing having an upset portion
Assignee: Park Ohio Holdings Corp
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Filing: 1976-04-02
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Granted: 1978-06-06
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Expires: 1996-04-02
Abstract
Abstract There is disclosed herein apparatus and method for heating metallic tubing having a thickened portion, by passing the same through an induction heater energized with power at a relatively high frequency whereby the temperature of the body of the tubing rises at a faster rate than the temperature of the said thickened portion and passing the said tubing through an induction heater energized with power at a relatively low frequency to cause the temperature of said thickened portion of the tubing to rise at a faster rate than the temperature of the body of the tubing, the ratio of the power applied at said low frequency relative to the power applied at said high frequency being such that said body and said thickened portion attain substantially the same predetermined final temperature upon exiting from said apparatus.
Inventors
- 👤 Louis J. Moliterno
- 👤 Reuel E. Jennings
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:12
CPC Classifications
C; C21; C21D; C21D9/00; C21D9/08; H; H05; H05B; H05B6/00; H05B6/02; H05B6/10; H05B6/101; H05B6/103; H05B6/104; Y; Y02; Y02P; Y02P10/00; Y02P10/25
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
137 words
Apparatus for progressively inductively heating metallic tubing having at least one relatively thickened portion, comprising at least one induction heating coil energized with power at a relatively high frequency which will cause the temperature of the body of the tubing to rise at a faster rate than the temperature of said thickened portion, and at least one induction heating coil energized with power at a relatively low frequency which will cause the temperature of said thickened portion of the tubing to rise at a faster rate than the temperature of the body of the tubing, means to adjust the ratio of the power applied at said low frequency relative to the power applied at the high frequency so that said body and said thickened portion attain substantially the same predetermined final temperature upon exiting from said apparatus.
Claim 2
Dependent Claim
137 words
Apparatus for progressively inductively heating metallic tubing having at least one relatively thickened portion, comprising at least one induction heating coil energized with power at a relatively high frequency which will cause the temperature of the body of the tubing to rise at a faster rate than the temperature of said thickened portion, and at least one induction heating coil energized with power at a relatively low frequency which will cause the temperature of said thickened portion of the tubing to rise at a faster rate than the temperature of the body of the tubing, means to adjust the ratio of the power applied at said low frequency relative to the power applied at the high frequency so that said body and said thickened portion attain substantially the same predetermined final temperature upon exiting from said apparatus.
Claim 3
Dependent Claim
19 words
The apparatus of claim 1 including means for continuously passing said tubing through all of said induction heating coils.
Claim 4
Dependent Claim
16 words
The apparatus of claim 1 wherein there is a quenching means following the last induction coil.
Claim 5
Dependent Claim
146 words
Method for progressively inductively heating sections of metallic tubing, each section having at least one relatively thickened portion, comprising passing said tubing through at least one induction heating coil energized with power at a relatively high frequency causing the temperature of the body of the tubing to rise at a faster rate than the temperature of said thickened portion, and passing said tubing through at least one induction heating coil energized with power at a relatively low frequency causing the temperature of said thickened portion of the tubing to rise at a faster rate than the temperature of the body, the ratio of the power applied at said low frequency relative to the power applied at said high frequency being such that said body and said thickened portion of each section attain substantially the same predetermined final temperature upon exiting from the last of said coils.
Claim 6
Dependent Claim
146 words
Method for progressively inductively heating sections of metallic tubing, each section having at least one relatively thickened portion, comprising passing said tubing through at least one induction heating coil energized with power at a relatively high frequency causing the temperature of the body of the tubing to rise at a faster rate than the temperature of said thickened portion, and passing said tubing through at least one induction heating coil energized with power at a relatively low frequency causing the temperature of said thickened portion of the tubing to rise at a faster rate than the temperature of the body, the ratio of the power applied at said low frequency relative to the power applied at said high frequency being such that said body and said thickened portion of each section attain substantially the same predetermined final temperature upon exiting from the last of said coils.
Claim 7
Dependent Claim
31 words
The method of claim 4 wherein the body outside diameters and wall thicknesses and the outside diameters and wall thicknesses of said thickened portions of all tubing sections are respectively identical.
Claim 8
Dependent Claim
24 words
The method of claim 5 wherein said sections of metallic tubing are passed through said heating coils consecutively in close proximity to each other.
Claim 9
Dependent Claim
38 words
The method of claim 6 wherein each section of said tubing is separated from each consecutive section of tubing by a distance equal to at least one quarter the length of the longest of said induction heating coils.
Claim 10
Dependent Claim
18 words
The method of claim 4 wherein each section of heated tubing is quenched following the final heating step.
Claim 11
Dependent Claim
127 words
Apparatus for progressively heating metallic tubing having at least one relatively thickened portion, comprising at least one heating means which will cause the temperature of the body of the tubing to rise at a faster rate than the temperature of said thickened portion, and at least one induction heating coil energized with power at a frequency which will cause the temperature of said thickened portion of the tubing to rise at a faster rate than the temperature of the body of the tubing, means to adjust the ratio of the power applied to said induction coil relative to the heating rate applied by said first heating means so that said body and said thickened portion attain substantially the same predetermined final temperature upon exiting from said apparatus.
Claim 12
Dependent Claim
127 words
Apparatus for progressively heating metallic tubing having at least one relatively thickened portion, comprising at least one heating means which will cause the temperature of the body of the tubing to rise at a faster rate than the temperature of said thickened portion, and at least one induction heating coil energized with power at a frequency which will cause the temperature of said thickened portion of the tubing to rise at a faster rate than the temperature of the body of the tubing, means to adjust the ratio of the power applied to said induction coil relative to the heating rate applied by said first heating means so that said body and said thickened portion attain substantially the same predetermined final temperature upon exiting from said apparatus.
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) | 1981-06-05 | 1981-12-05 | 1982-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-06-05 | 1985-12-05 | 1986-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-06-05 | 1989-12-05 | 1990-06-06 | $7700.00 | Window Closed / Lapsed |