GB2068098A - Induction heating of concrete castings - Google Patents
Induction heating of concrete castings Download PDFInfo
- Publication number
- GB2068098A GB2068098A GB7902371A GB7902371A GB2068098A GB 2068098 A GB2068098 A GB 2068098A GB 7902371 A GB7902371 A GB 7902371A GB 7902371 A GB7902371 A GB 7902371A GB 2068098 A GB2068098 A GB 2068098A
- Authority
- GB
- United Kingdom
- Prior art keywords
- coil
- bed
- concrete
- casting
- castings
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 238000005266 casting Methods 0.000 title claims abstract description 51
- 239000004567 concrete Substances 0.000 title claims abstract description 34
- 238000010438 heat treatment Methods 0.000 title claims description 13
- 230000006698 induction Effects 0.000 title claims description 5
- 238000000034 method Methods 0.000 claims abstract description 15
- 239000003302 ferromagnetic material Substances 0.000 claims abstract description 7
- 230000003014 reinforcing effect Effects 0.000 claims abstract description 7
- 230000005674 electromagnetic induction Effects 0.000 claims abstract description 3
- 230000005291 magnetic effect Effects 0.000 claims description 6
- 230000002787 reinforcement Effects 0.000 claims description 6
- 229910000831 Steel Inorganic materials 0.000 claims description 4
- 230000001133 acceleration Effects 0.000 claims description 4
- 230000005672 electromagnetic field Effects 0.000 claims description 4
- 239000010959 steel Substances 0.000 claims description 4
- 230000033228 biological regulation Effects 0.000 claims description 2
- 230000005294 ferromagnetic effect Effects 0.000 claims description 2
- 150000002505 iron Chemical class 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 claims description 2
- 239000000463 material Substances 0.000 claims description 2
- 239000011513 prestressed concrete Substances 0.000 claims description 2
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B3/00—Drying solid materials or objects by processes involving the application of heat
- F26B3/32—Drying solid materials or objects by processes involving the application of heat by development of heat within the materials or objects to be dried, e.g. by fermentation or other microbiological action
- F26B3/34—Drying solid materials or objects by processes involving the application of heat by development of heat within the materials or objects to be dried, e.g. by fermentation or other microbiological action by using electrical effects
- F26B3/347—Electromagnetic heating, e.g. induction heating or heating using microwave energy
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B11/00—Apparatus or processes for treating or working the shaped or preshaped articles
- B28B11/24—Apparatus or processes for treating or working the shaped or preshaped articles for curing, setting or hardening
- B28B11/245—Curing concrete articles
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Microbiology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Molecular Biology (AREA)
- Biomedical Technology (AREA)
- Biotechnology (AREA)
- Electromagnetism (AREA)
- Health & Medical Sciences (AREA)
- Physics & Mathematics (AREA)
- General Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- General Induction Heating (AREA)
Abstract
Method and apparatus for accelerating the curing of concrete utilising electro-magnetic induction in order to generate heat. Specifically, an electrical coil or coil arrangement is suspended over and arranged to traverse a concrete casting bed in a prescribed manner covering concrete casting or castings thereon. Secondary heat- generating means associated with the casting or castings may comprise ferro- magnetic material of the bed itself and/or of reinforcing wires or rods of the castings. The latter will usually be electrically short-circuited together and RF coil-energising frequencies may be used to increase efficiency.
Description
SPECIFICATION
Induction heating of concrete castings
The invention relates to concrete curing. In particular it concerns acceleration of concrete curing in order to speed up production.
We have made a previous proposal to achieve accelerated curing, in relation particularly to reinforced, pre-stressed concrete beams, by the passage of electrical current along reinforcing wires or rods thereof. Other proposals of which we are aware involve the use of a steel bed onto which the beams are cast and associated heating pipes or electrical elements usually below the bed.
It is an object of this invention to facilitate acceleration of concrete curing without the need for such bed heating systems and/or without direct passage of electrical current through any reinforcing wires of the concrete casting.
To this end, we now propose that electro-magnetic induction be used to generate heat via secondary means associated with concrete casting or castings, usually as material of the bed and/or reinforcing wires or rods.
We preferto achieve this end by a coil or coil arrangement suspended above the concrete casting, and traversable over the casting in a prescribed manner, usually in a repeated pattern, the coil or coil arrangement being supplied with varying, usually alternating, electric current. As applied to concrete beam casting, a preferred coil or coil arrangement effectively spans a bed on which a plurality of beams are cast and reversibly traverses the bed linearly from end to end, though the beams may be at right angles to the direction of traverse. A typical bed of 50 metres length and 2 metres width may have a coil or coil arrangement also with a 2 metre dimension and traversable along the length of the bed.
The coil or coil arrangement may be of spiral wound type and will, of course, usually incorporate laminated iron coring which may be of a geometry that particularly enhances or promotes induction heating as desired.
For heating of a steel bed as such and by reason of eddy current generation and magnetic hysteresis losses, it is feasible to use mains frequencies, i.e. 50 or 60 cycles per second, though higher frequencies may well be preferred. The amount of heat generated in any discrete reinforcement wires or rods in such a way is likely to be small but can be made great by short circuiting those wires or rods together to make a closed loop or loops. Efficiency of operation, at least in relation to heating of reinforcement wires or rods, may be improved at higher frequencies, say RF frequencies, by increased concentration of induced current flow at skin portions thereof. Regulation of current flow may be provided for by particular values of, or variable electrical components in interconnections of the wires or rods.
1. A method of accelerating concrete curing wherein an electrical coil or coil arrangement is located in the vicinity of concrete casting or castings, and heat is generated by supplying varying electrical current to the coil or coil arrangement to induce an electro-magnetic field in the vicinity of the concrete casting or castings with which is associated heat generating means energised by said field.
2. A method according to claim 1, wherein the coil or coil arrangement is traversed over the concrete casting or castings.
3. A method according to claim 1 or claim 2, wherein the coil or coil arrangement is caused to couple its electro-magnetic field into ferromagnetic material constituting heat generating means.
4. Apparatus for accelerating concrete curing comprising a concrete casting bed, an electrical coil or coil arrangement as a primary means for generating a varying magnetic field when energised with a varying electrical current, and means for suspending the coil or coil arrangement above positions of concrete casting or castings on the bed so that said varying electrical magnetic field will energise heat generating means associated with said casting or castings.
5. Apparatus according to claim 4, comprising means whereby the suspended coil or coil arrangement is traversable over the casting bed in a prescribed way.
6. Apparatus according to claim 4 or claim 5, wherein said heat generating means comprises ferromagnetic material.
7. Method or apparatus according to claim 3 or claim 6, wherein said ferromagnetic meterial is of a or the casting bed.
8. Method or apparatus according to claim 3, 6 or 7, wherein said ferromagnetic material comprises reinforcement wires or rods of the casting or castings.
9. Method or apparatus according to claim 8, wherein said wires or rods are intercoupled electrically in a closed loop or loops.
10. Method or apparatus according to any preceding claim, wherein alternating RF electrical current is used.
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (10)
1. A method of accelerating concrete curing wherein an electrical coil or coil arrangement is located in the vicinity of concrete casting or castings, and heat is generated by supplying varying electrical current to the coil or coil arrangement to induce an electro-magnetic field in the vicinity of the concrete casting or castings with which is associated heat generating means energised by said field.
2. A method according to claim 1, wherein the coil or coil arrangement is traversed over the concrete casting or castings.
3. A method according to claim 1 or claim 2, wherein the coil or coil arrangement is caused to couple its electro-magnetic field into ferromagnetic material constituting heat generating means.
4. Apparatus for accelerating concrete curing comprising a concrete casting bed, an electrical coil or coil arrangement as a primary means for generating a varying magnetic field when energised with a varying electrical current, and means for suspending the coil or coil arrangement above positions of concrete casting or castings on the bed so that said varying electrical magnetic field will energise heat generating means associated with said casting or castings.
5. Apparatus according to claim 4, comprising means whereby the suspended coil or coil arrangement is traversable over the casting bed in a prescribed way.
6. Apparatus according to claim 4 or claim 5, wherein said heat generating means comprises ferromagnetic material.
7. Method or apparatus according to claim 3 or claim 6, wherein said ferromagnetic meterial is of a or the casting bed.
8. Method or apparatus according to claim 3, 6 or 7, wherein said ferromagnetic material comprises reinforcement wires or rods of the casting or castings.
9. Method or apparatus according to claim 8, wherein said wires or rods are intercoupled electrically in a closed loop or loops.
10. Method or apparatus according to any preceding claim, wherein alternating RF electrical current is used.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB7902371A GB2068098A (en) | 1979-01-23 | 1979-01-23 | Induction heating of concrete castings |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB7902371A GB2068098A (en) | 1979-01-23 | 1979-01-23 | Induction heating of concrete castings |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB2068098A true GB2068098A (en) | 1981-08-05 |
Family
ID=10502679
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB7902371A Withdrawn GB2068098A (en) | 1979-01-23 | 1979-01-23 | Induction heating of concrete castings |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2068098A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009027813A3 (en) * | 2007-08-31 | 2009-06-18 | Danish Concrete Technology Hol | Process for curing and drying reinforced concrete |
| CN112157794A (en) * | 2020-10-26 | 2021-01-01 | 中国电建集团成都勘测设计研究院有限公司 | Concrete self-curing device and using method thereof |
-
1979
- 1979-01-23 GB GB7902371A patent/GB2068098A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009027813A3 (en) * | 2007-08-31 | 2009-06-18 | Danish Concrete Technology Hol | Process for curing and drying reinforced concrete |
| CN112157794A (en) * | 2020-10-26 | 2021-01-01 | 中国电建集团成都勘测设计研究院有限公司 | Concrete self-curing device and using method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US2902572A (en) | Induction heating of metal strip | |
| CA1083653A (en) | Electromagnetic centrifuging inductor for rotating a molten metal about its casting axis | |
| US4321444A (en) | Induction heating apparatus | |
| DE60214711T2 (en) | Magnetic heater | |
| US3424886A (en) | Induction heating | |
| GB2068098A (en) | Induction heating of concrete castings | |
| US3041434A (en) | Method of and apparatus for inductively heating metal | |
| US4484615A (en) | Electro-magnetic stirring | |
| US2970830A (en) | Varying the falling speed of a stream of molten metal | |
| JPS60127056A (en) | Casting device with electromagnetic pump used for casting liquefied metal | |
| US1383963A (en) | Heat treatment of tramway and other rails | |
| JP4441435B2 (en) | Linear moving magnetic field type electromagnetic stirrer | |
| US4454909A (en) | Mold stator for electromagnetic stirring | |
| US3691339A (en) | Multi-phase induction heating device | |
| JPS5542109A (en) | Surface defect preventing method of continuously cast slab | |
| ATE12597T1 (en) | METHOD OF ELECTROMAGNETIC STIRRING IN METAL CONTINUOUS CASTING. | |
| JPS60130452A (en) | Molten metal casting equipment with electromagnetic pump | |
| US1743956A (en) | Induction furnace | |
| JPH11216552A (en) | Electromagnetic meniscus control device of continuous casting and control method therefor | |
| JPS63317630A (en) | Induction heater | |
| JPH0642982B2 (en) | Metal flow control method in continuous casting mold | |
| US4435820A (en) | Channel induction furnaces | |
| JPS56152928A (en) | Residual stress relieving device of h-beam | |
| SU1171537A1 (en) | Method of local heating of articles and device for effecting same | |
| JPS5791855A (en) | Electromagnetic stirrer in continuous casting facility |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |