Patent US3928090A successfully refreshed from Google Patents.
US3928090A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat treatment of steel
Assignee: British Steel Corp
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Filing: 1973-03-08
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Granted: 1975-12-23
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Expires: 1993-03-08
Abstract
Abstract A steel body at red heat or higher temperature is heat treated by sequentially carrying it through a descaling unit, where scale is removed by water jets at an impact force above 2.5 kg/cm2, and then into an accelerated cooling process such as a quench rig where it is cooled rapidly down through its transformation temperature. If the temperature is below transformation after descaling the steel body is reheated without new scale formation before passing to accelerated cooling. Cooling water and surface quality are thereby improved.
Inventors
- 👤 Keith Randerson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 09:53
CPC Classifications
C; C21; C21D; C21D1/00; C21D1/82; B; B21; B21B; B21B45/00; B21B45/04; B21B45/08; C21D1/62
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
77 words
A METHOD OF HEAT TREATING A STEEL BODY HAVING SURFACE SCALE COMPRISING APPLYING A STREAM OF WATER AT AN IMPACT FORCE OF AT LEAST 2.5 KG/CM2 OVER SUBSTANTIALLY THE WHOLE OF THE SURFACE OF THE BODY WHILE IT IS RED HEAT OR HIGHER TEMPERATURE TO REMOVE THE SCALE AND SUBSEQUENTLY SUBJECTING THE BODY WITHOUT SUBSTANTIAL FURTHER SCALE FORMATION TO A CONVENTIONAL ACCELERATED COOLING PROCESS FROM A TEMPERATURE ABOVE ITS CHANGE POINT TO A LOWER TEMPERATURE THROUGH TRANSFORMATION
Claim 2
Independent Claim
77 words
A METHOD OF HEAT TREATING A STEEL BODY HAVING SURFACE SCALE COMPRISING APPLYING A STREAM OF WATER AT AN IMPACT FORCE OF AT LEAST 2.5 KG/CM2 OVER SUBSTANTIALLY THE WHOLE OF THE SURFACE OF THE BODY WHILE IT IS RED HEAT OR HIGHER TEMPERATURE TO REMOVE THE SCALE AND SUBSEQUENTLY SUBJECTING THE BODY WITHOUT SUBSTANTIAL FURTHER SCALE FORMATION TO A CONVENTIONAL ACCELERATED COOLING PROCESS FROM A TEMPERATURE ABOVE ITS CHANGE POINT TO A LOWER TEMPERATURE THROUGH TRANSFORMATION
Claim 3
Dependent Claim
25 words
A method as claimed in claim 1 wherein the stream of water is provided from a nozzle or nozzles past which the body is moved.
Claim 4
Dependent Claim
14 words
A method as claimed in claim 1 wherein the body is a steel plate.
Claim 5
Dependent Claim
22 words
A method as claimed in claim 1 wherein the impact force of the stream of water is from 3 to 6 kg/cm2.
Claim 6
Dependent Claim
29 words
A method as claimed in claim 1 wherein the water is supplied at a rate of at least 2 gm on every square centimeter of surface to be descaled.
Claim 7
Dependent Claim
29 words
A method as claimed in claim 1 wherein the stream of water is applied over the surface scale while the body is at a temperature of at least 900*C.
Claim 8
Dependent Claim
33 words
A method as claimed in claim 1 wherein the stream of water is applied over the surface scale while the body is at a temperature above the upper change point of the body.
Claim 9
Dependent Claim
25 words
A method as claimed in claim 1 wherein after removal of the surface scale the body is passed directly to said conventional accelerated cooling process.
Claim 10
Dependent Claim
38 words
A method as claimed in claim 8 wherein the first stages of transformation are allowed to occur while descaling the body and cooling through transformation is completed in the conventional accelerated cooling process, cooling being continuous through transformation.
Claim 11
Dependent Claim
45 words
A method as claimed in claim 1 wherein after removal of the surface scale and before subjecting the body to the conventional accelerated cooling process the body is reheated to a temperature above the upper change point in a manner which will minimise scale formation.
Claim 12
Dependent Claim
20 words
A method as claimed in claim 10 wherein the body is reheated in a reducing flame or by infra-red radiation.
Claim 13
Dependent Claim
17 words
A method as claimed in claim 1 wherein the conventional accelerated cooling process is a quenching process.
Claim 14
Dependent Claim
17 words
A method as claimed in claim 12 wherein the quenching medium is water, oil, oil/water or brine.
References Cited (Backward Citations)
US3629015A
Cited
US3756869A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-22 | 1979-06-23 | 1979-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-22 | 1983-06-23 | 1983-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-22 | 1987-06-23 | 1987-12-23 | $7700.00 | Window Closed / Lapsed |