SE447069B - SET TO REDUCE LOCAL TEMPERATURE INNOVATIVES ON THE HEAT COLLECTOR - Google Patents

Description

10 15 20 25 30 35 , ..-- ,, - ~ __. p _.____.- 447 069 once install heat equalization stations, often heat insulated and also heat storage, where the substance is stopped for temperature turn equalization. The result has not been satisfactory then temperature loss and residual temperature irregularities still caused poor measurement tolerances in the finished rolling as well capacity reduction in the rolling mill. Nor has the supply stations with heat supply results when both areas with colder spots and adjacent heat added to the affected areas. Temperature irregularities have still remained even if the colder spots were eliminated.

The rolling mill's various pairs have also been provided with an increasing number advanced control equipment. However, it remains to be seen current kiln and rolling technology constitute temperature irregularities in the steel blank today a considerable quality apartment.

SUMMARY OF THE INVENTION: With this invention, the limited cooler portions can in a steel blank for rolling, which remains after heating in, for example, a reheating oven, equalized to the desired temperature level.

The temperature equalization takes place through a local heat supply directed at the colder parts of the steel blank.

Heating and rolling can thereby take place with increasing degree of freedom and with an improved quality as a result.

The invention will be described in more detail in claims, in subsequent sections and in exemplary embodiments and with help of attached figures, of which figure 1 shows a plan of a rolling mill for wide sheet metal and figure 2 how a substance abuts a water cooler carrier pipes.

DETAILED DESCRIPTION OF THE INVENTION: The temperature equalization is achieved by turning the steel blank on suitable place in the rolling, usually before the plastic processing, very limited heat in the place there the steel blank has a temperature unevenness. The difficulty of locate and control this heating during rolling or when the steel blank is in motion means that the proposed invention is especially applicable to the heated substance before rolling 1> ooR lo fl ßïlï fl 10 15 20 25 30 35 f ... ß .. - .. nww-à ... 447 069 placed in a fixed position, so that the colder parts lie in the middle of the permanently installed heat source. In this waiting position, the cold portions of the steel blank are heated from one side for the time required for the desired temperature increase must be achieved. Proposed method is associated with heating of steel blanks in a so-called reheating furnace in particular applicable in the position which the substance naturally acquires when it taken out of the oven and placed on the hot rolling path, which leads to the rolling mill.

The local heat supply can be generated in many ways.

Examples are induction heating, gas and oil. burner and electric heat radiation. Preferred is induction- heating as this can easily be concentrated to just those areas that need to be heated without surrounding lots significantly affected. The induction heating can also be controlled to be further specified to the right areas.

It can also be used freely in the room without surrounding environment is affected. To avoid energy losses through radiation from the hot steel blank during the heating The site can also be insulated against the surroundings.

EXAMPLE: Steel blanks, 4, with a length of ll meters and a transverse sections with an average width of 1200 mm and a thickness of 220 mm are heated in an oil-fired oven, 1, to about 12500C. Maximum heating the time amounts to 300 tons / hour. In the oven room, steel the substance, 4, from both the top and bottom with a large number oil burners. This is accomplished by the subject, 4, under the transport through the oven room rests on a total of 11 pieces water-cooled carrier pipes, 2. To avoid one as much as possible excessive temperature drop in the steel blank, 4, above the support pipes, 2, these are provided with heat-insulating material, 3, and intermediate metallic material, 13. Nevertheless the temperature drop in the substance, 4, becomes noticeable and leads to unfavorable temperature gradients for rolling, 14.

At the outlet end of the oven, 1, the heated substance will be naturally laid down in a fixed position on a so-called hot roller, 5, for further transport to the rolling mill.

QÜÄLITY 10 15 V, --.-. ..._._..._..__ 447 069 4 At the closing point on the hot roller, 5, heat the steel blank, 4, for a short time by means of a heat source, 6, which are inductors located in the roller coaster, 5, so that they heat the substance, 4, only on that side and on those places where the carrier tubes, 2, in the oven, 1, caused unfavorable temperature gradients, 14. The inductors are fed from a for purpose specially dimensioned power plant, 7 and can regulated individually. Through this well-suited heat supplement, both in quantity and area, together with subsequent rolling in universal rolling mill, 9, allows residual variations in temperature of the rolled blank on arrival at the finished pair, ll, are negligible.

After the inductive heating, the coals are separated the blank surface in a spray box, 8. In universal rolling mill, 9, coil box, 10, and finished pairs, 11, the blank is rolled out into a long strip, which after cooling rolls together into a strip roll in one reel, 12. pooR QUÅUW

Claims (1)

-._..- <-..._, _.._..._..... 447 069 PATENT REQUIREMENTS Method of reducing temperature irregularities of a steel blank (4) during hot rolling, characterized in that the steel blank (4) is heated after regular heating with permanently mounted induction heaters towards the places of the blank (4) where the temperature deviates unfavorably and that the blank (4) then lies still in a fixed place on the hot coil (5) directly after the ordinary heating furnace (1). ..-.....-. - _ _ _ ._ _ .. * r POOR QUALmf