SU899688A1 - Convector ring - Google Patents

Description

(54) CONVECTOR RING

one

The invention relates to metallurgical heat engineering, and more specifically to equipment of bell-type furnaces for heat treatment of metal in coils.

Known convector ring containing cast or welded discs with radial or spiral channels formed by the plane of the disc, the side surface of the ribs of the rings.

Convector rings installed between the rolls of the foot provide intensive heating of the set-up of bell-type furnaces due to convective heat transfer by circulating protective gas from the muffle to the end surfaces of the rolls C.

However, the efficiency of heat transfer from the circulating gas to the end surfaces of the coils depends on the design of the rings and does not exceed, as a rule, 15-20 W / m.

It is also known convector hoof containing corrugated t2l discs.

This design of the convector ring is difficult to manufacture, inconvenient to operate, and does not provide a high heat transfer coefficient from the circulating gas to the end surfaces of the coils.

Closest to the invention by its technical nature is a convection ring containing disks interconnected by partitions forming the SZ channels.

The efficiency of this convector ring is low, determined by convective heat transfer from gas to the ends of the coils, and limited by the ability of devices to circulate shielding gas. In addition, the circulating shielding gas draws heat from the muffle, informs the heated metal only a fraction (l 45-t 75%) of heat generated by heating devices located outside the working space.

Claims (3)

The purpose of the invention is to intensify the heating of the charge, increase the productivity of bell-type furnaces and reduce the specific energy consumption for heating the metal. This goal is achieved by the fact that the convector ring containing discs interconnected by radial partitions forming the channels is provided with electric heating elements installed in the channels. Fig, 1 shows a convector ring, a general view; in fig. 2 shows section A-A in FIG. 1. The convector ring consists of two disks 1 and 2, parallel to each other with radial partitions 3 and channels 4 that form from the central aperture to the periphery, in which electrically heated elements 6 are placed on insulated cases 5, interconnected with each other. plug connection to an AC power source. Convector ring is made as follows. In the radial channels 4, formed by partitions 3 of the cast lower disc 2 are laid the inserts 5, embedded in a heat-resistant electrically insulating material (for example, from ceramics). Electrical inserts 5 (wire or ribbon) are placed on the inserts 5. All this construction is covered with a cast disk 1 and welded to the partitions 3 of the lower disc 2. When loading coppack furnaces, the convector ring is placed in a stop between the ends of the rolls in normal order. A roll stack is sealed with a muffle and heat insulating cap without heating devices. After that, the leads of the electric heaters 6 of the convection rings are connected to an AC source of 38 O / 22 O (each ring is connected separately). Metal heating is carried out. Electric energy, transforming into a convector ring into heat (t TOO-ZOO C) is transmitted by the radiation and thermal conductivity of thorium metal coils, carried out intensive heating of the charge in the direction of its greatest thermal conductivity, and by convective, due to the heating of the circulating protective gas 8 84, 4 co-vector peg. Placing electric heating elements in the convector gauge channels allows the heat source to be as close as possible to the metal to be heated, to increase the intensity of heat exchange between the energy source and the metal, as well as the energy source and the circulating protective gas, which ultimately leads to a performance of the cavity cavity and economy. thermal energy. Placing sources of heat energy directly in the roll stack allows you to significantly increase the efficiency of the bell furnace (up to 9O%), reduce the heat loss of the furnace, bring the specific energy consumption for metal heating to a value close to the theoretically possible, increase the uniformity and speed of heating metal rolls. By adjusting the power of the electric heaters for various convector rings, it is possible to achieve a very high heating uniformity both in the height of the foot and in the radial direction of the metal rolls, which increases the furnace productivity by 15%. Claims of the invention A convector ring containing discs interconnected by partitions forming channels, characterized in that, in order to intensify the heating of the charge and increase the productivity of bell furnaces, it is equipped with electric heating elements installed in the channels. Sources of information taken into consideration during the examination 1.Anterman V.I. and others. Bell furnaces. M., Metallurgists, 1965, p. 123, fig. Xi -7. 2. US Patent N 3069148, cl. 266-5, 1973. 3. Japanese patent number 279928, cl. C 21 (10A.710.3), 1975.