SU1671714A1 - Bell-type furnace - Google Patents

Abstract

The invention relates to devices for the heat treatment of metal, preferably loose coils, and can be used in the metallurgical and other industries. The goal is to increase the productivity of the furnace. For this, the cover of the bell-s muffle is made of conical and reverse conical sections mating to each other, and the convector rings have the form of inverted truncated cones, on the lower and upper parts of which are made shells and conical flaps. The furnace provides heating of fluffed coils due to the passage of coolant flows between the coils of the coils with equal speed, which ensures convective heating and an increase in furnace productivity. 2 Il.

Description

The invention relates to devices for the heat treatment of metal, preferably fluffed coils, and can be used in the metallurgical and other industries.

The aim of the invention is to increase the productivity of the furnace.

Figure 1 shows a furnace, a general view in longitudinal section; Figure 2 shows a convector ring.

The bell furnace contains a stand 1, a fan 2 with a guide device 3 and a heating cap 4 with heaters 5. At stand 1 a stand 6 for rolls 7 is installed. The furnace also contains a muffle 8, the lid of which contains a conical section 9, coupled with a section 10, made in the form of an inverse cone, the convector rings 11 are made in the form of inverse cones 12, on the lower and upper

the edges of which are shell 13 and 14, respectively.

At the lower edges of the convector rings 11 there are conical flaps 15. The rings 11 are provided with stiffening elements 16.

Cap furnace works as follows.

The first roll 7 is installed on the stand 6. The first conical ring 11 is mounted on top so that the inner turn of the roll 7 fits tightly to the sidewall 14. A second roll 7 is installed on the first ring 11, and the outer turns of the roll 7 should fit tightly to the sidewall 14. In this way, a stack of rolls is carried out. After that, the foot set muffle 8, which section 10 enters the central hole of the upper roll 7.

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A heating cap 4 is installed, the heaters 5 are turned on. The muffle 8 is heated by the radiation of the heaters. The fan 2 and the coolant are turned on and the heat from the walls of the muffle 8 is circulated in the muffle space of the hot air heater. During the upward flow of the coolant, a part of the gas is separated by the flaps 15 and enters the gap between the lower surface of the ring 11 and the upper end of the roll 7. Under the action of the vacuum generated by the fan 2, this flow of the coolant is divided into several downward flows with equal speed passing through the gaps between the coils of coils 7, giving heat to the coils of the coil and thereby heating it. Due to the close fit of the shells 13 and 14 to the inner and outer coils of the rolls, direct heat transfer to the suction side of the fan 2 is eliminated through the gaps between the rolls and convector rings. For the upper roll 7, the muffle cap 8 serves as a convector ring.

When the coolant enters the inter-turn gaps, its quantity gradually decreases, but at the same time the channel section through which the coolant enters the gaps located closer to the internal opening of the coil, i.e., decreases. the speed of the heat transfer medium is constant in all the inter-turn gaps. In this way, the heating efficiency of the charge improves, the heating time decreases and, consequently, the heating output decreases. When the height of the foot of the rolls 7 is changed, the height of the stand 6 is changed so that there is no gap between the section 10 of the muffle cover 8 and the upper end of the roll 7.

The implementation of convector rings in the form of inverse cones and the presence on the lid of the muffle area, made in the form of a reverse cone, provides equal speed

downstream coolant flow between coils, as the amount of coolant decreases (removal of a portion of coolant to the peripheral channels of the coils) and the channel cross section between the upper ends of the coils and the bottom (guide) surfaces of the convector decreases. rings. The presence of conical flaps of convector rings and the conical part

The muffle cap allows you to guarantee a part of the heat transfer fluid from the total flow and direct it to the appropriate roll. The presence of shells on the upper and lower edges of the convector rings, as well as

the muffle lid section made in the form of a reverse cone ensures that the flow of the heat transfer fluid first passes through the interturn clearances of the rolls and then to the fan’s suction side, since they exclude

passing streams over the ends of the rolls directly to the low pressure zone of the fan.

Consequently, the heating of fluffed coils is ensured by passing

coolant flows between turns of the rolls with equal speed, i.e. convective heating occurs, which increases the heating rate and, consequently, increases the productivity of the furnace.

Claims (1)

Invention Formula A bell furnace for heating fluffed coils, containing a stand, a muffle, a heating hood, a fan with a guiding device and convector rings, characterized in that, in order to increase productivity, the upper end of the muffle is made of adjacent direct and reverse conical sections, and convector rings are made in the form of inverse truncated cones, limited by peripheral and central shells and placed around the periphery of the flaps. S v Sl 1216