US3755010A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tandem scan hardening of pipe
Assignee: Park Ohio Holdings Corp
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Filing: 1971-09-08
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Granted: 1973-08-28
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Expires: 1991-09-08
Abstract
Abstract There is disclosed herein two induction scan hardening and tempering lines wherein pipe is moved axially one way through an induction coil and quench for hardening and in the opposite direction through the coil for tempering, as phases of predetermined cycles. A single supply conveyor sequentially conveys new pipes to a position adjacent to the hardening lines, and transfer means alternately deposit a pipe first on one hardening line and then the other. Automatic control means control the cycles in such manner as to cause the cycles to overlap whereby fully treated pipe is discharged at intervals substantially less than the time consumed by a single cycle.
Inventors
- 👤 L Moliterno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:15
CPC Classifications
C; C21; C21D; C21D9/00; C21D9/08; C21D1/00; C21D1/34; C21D1/42; Y; Y02; Y02P; Y02P10/00; Y02P10/25
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
43 words
The method as set forth in claim 1: the step of sensing the presence of a pipe being treated at either hardening line and shifting a new pipe from the load position laterally, only to a hardening line prepared to receive the pipe.
Claim 2
Dependent Claim
33 words
The method as set forth in claim 1: the hardening of the pipe including the step of quenching both the interior and exterior of the pipe as it passes from the induction coil.
Claim 3
Independent Claim
136 words
The method of tandem scan hardening and tempering of pipe in two parallel pipe hardening lines, each line including an induction coil and quench means; the step of conveying a first pipe at a predetermined speed through a first of the two hardening lines in a forward direction to harden the pipe; the step of moving the first pipe rearwardly through the same hardening line to temper the pipe; the step of delivering a second pipe to the second hardening line before completion of the hardening of the first pipe at the first hardening line; the step of delivering a third pipe to the first hardening line and transferring the first pipe away from the first hardening line before completion of the hardening of the second pipe in said second hardening line, in a continuous cycle.
Claim 4
Independent Claim
182 words
A method of treatment of successive pipes by scan hardening and tempering thereof in like manner in two pipe treating lines having the entrance ends thereof disposed adjacent to each other, each line including an induction coil and quench means, the method comprising: the steps of sequentially conveying pipes to a load position adjacent to the entrance ends of the pipe treating lines; the step of conveying a first pipe from the load position through a first of the pipe treating lines in a forward direction to harden the pipe; the step of moving the first pipe rearwardly through the same pipe treating line to temper the pipe; the step of delivering a second pipe to the second pipe treating line for like treatment before completion of treatment of the first pipe at the first pipe treating line; and the step of transferring the first pipe away from the first pipe treating line and delivering a third pipe to the first pipe treating line before completion of treatment of the second pipe in the second pipe treating line, in continuous overlapping cycles.
Claim 5
Dependent Claim
44 words
The method as set forth in claim 5 including the step of sensing the presence of a pipe being treated at either pipe treating line and causing a new pipe to be shifted from the load position Into an empty pipe treating line only.
Claim 6
Independent Claim
242 words
The method of treatment of large diameter steel pipe by tandem scan hardening and tempering in two pipe treating lines having the entrance ends thereof disposed adjacent to each other, each line including an induction coil and quench means; the step of sequentially moving pipes to a load position adjacent to the entrance ends of the pipe treating lines; the step of shifting alternate pipes from the load position to the respective pipe treating lines; the sequential steps at each pipe treating line of conveying each pipe forwardly through the coil and progressively heating the pipe to quenching temperature, conveying the pipe through the quench means and quenching the pipe to harden the pipe, conveying the pipe back through the coil for tempering the pipe, and conveying the pipe away from the pipe treating line, while maintaining the speed of new pipe conveyed to the load position, and the speed of hardened pipe moving back through the coil for tempering, substantially greater than the speed of the pipe through the coil and quench means during hardening of the pipe whereby the second pipe is delivered to the second pipe treating line before completion of treatment of the first pipe, and the first pipe is transferred away from the first pipe treating line and the third pipe is delivered to the first pipe treating line before completion of treatment of the second pipe in the second pipe treating line, in continuous overlapping cycles.
Claim 7
Dependent Claim
85 words
The method of treatment of large diameter steel pipe as set forth in claim 7 wherein the pipe is conveyed axially through each pipe treating line with the pipe being tilted downwardly at its forward end and including the step of maintaining the pipe in the extreme forward position after quenching for a predetermined time to allow quench liquid to drain therefrom, the relative speeds of the pipes causing hardening of a new pipe to begin before completion of drainage of the prior delivered pipe.
Claim 8
Dependent Claim
40 words
The method of treatment of large diameter steel pipe as set forth in claim 7 wherein the relative speeds of the pipes causes hardening of a new pipe to begin before completion of the hardening of the prior delivered pipe.
References Cited (Backward Citations)
US3407099A
Cited
US3623716A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-27 | 1977-02-26 | 1977-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-27 | 1981-02-26 | 1981-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-27 | 1985-02-26 | 1985-08-28 | $7700.00 | Window Closed / Lapsed |