SU924128A1 - Bell-type furnace - Google Patents

Description

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

Known electric bell-type furnaces, consisting of a stand, a heating hood with electric heating elements placed on it! and a central electric heater, a muffle with a central dead-end pipe. Cooling is provided by the fan air of the outer side surface of the muffle after removing the heating cap from it. The use of an air cooling cap with a fan allows speeding up the cooling of the charge by 10-15% (1].

However, its design is very cumbersome, difficult to manufacture and ineffective.

Known bell-type furnace, consisting of a stand, heating cap, muffle, dushanuyu installation, which is a pipe with holes for watering the outer surface of the muffle with water and a pipe for feeding the cooler [2].

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However, the cooling time of the charge in the case of the use of the perfume units is also very long.

Known bell furnace, containing a stand, a heating cap, a muffle with a central stub tube, a pipe for supplying a cooler [3].

In this furnace, the process of cooling metal coils from the side of their inner side surface takes place. in case of failure of the cooling device, which leads to the ingress of water into the central tube of the muffle (when using a muffle of this design), the operating conditions of the muffle significantly deteriorate due to thermal shock, its tightness is disturbed.

The purpose of the invention is to reduce the irregularity of the temperature field over the cross section of the charge, reducing the duration of the cooling of the charge under

_ bell-type muffle. ovens.

 This goal is achieved by

that the bell furnace is equipped with a muffle installed in a dead-end pipe

coaxially to the pipeline with an additional pipe with a plugged end

, and with the support ring on the other end,

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924128

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wherein the support ring is placed on the muffle and has radial ribs forming channels between the inner surface of the support ring and the muffle, which are connected to the pipe cavity; the lower end of the pipeline is separated from the bottom of the pipe at a distance of 0.2-1.0 in diameter of the pipe.

Figure 1 shows the bell furnace, General view; figure 2 - section A — A in figure 1.

The bell furnace consists of stand 1, a muffle 2 with a central dead-end pipe 3, installed on stand 1, a cooling pipe 4, resting freely on the cover of the muffle 2, pipe 5, placed in the cooling pipe 4 and connected to the cooler supply system. The pipe 5 ends with a nozzle b in the bottom of the cooling pipe 4. The upper part of the cooling pipe 4 is open, provided with support flanges 7 having support ribs 8 forming between the inner surface of the flanges Τ 'and the outer surface of the muffle cover 2 radial guide channels 9 for cooling overflow from cooling tube 4 on the outer side surface of the muffle 2.

The distance between the lower end of the cooler supply pipe and the bottom of the cooling pipe is chosen equal to 0.2-1.0 (where ϋ _t p is the internal

diameter of the cooling tube, b - distance).

When N <0.2 E _t p in terms of operation of the cooling device may be a risk of ignition of the cooling tube and the coolant feed pipe. When> E _t p increases the uneven cooling of the height of the foot rolls, because in the process of cooling the most lagging behind are the lower rolls of the foot. The total cross-sectional area of the radial channels formed by the outer surface of the muffle cap, the ribs and the inner surface of the flange of the cooling tube (5c must be larger and equal to the cross-sectional area of the cooler supply pipe (5 _П ), that is, 5 _X $ §η · Otherwise In this case, the excess part will be removed through the open top opening of the cooling tube.

Kolpakova oven works as follows.

After the end of the heating process and holding the metal, the heating cap is removed and transferred to another stand. Into the internal cavity of the dead-end pipe 3. muffle 2, lower the cooling pipe .4 up to the stop by its flanges 7 on the muffle cover 2. Into the cavity of the cooling pipe 4 enter the pipeline 5 connected to the water supply system; The nozzle b of the pipeline 5 is placed at the bottom of the cooling pipe 4. Water flows through the pipe 5 through the nozzle b into the cooling pipe 4, takes heat from its walls, overflows through the upper open edge and directs the cooling of the outer side surface 9 muffle 2.

The presence of a cooling tube in the inner cavity of the foot of the coils allows for bilateral cooling of the coils of metal, increasing the heat exchange surface, reducing the unevenness of the temperature field during cooling of the coils of metal.

Claims (2)

Claim A bell furnace containing a heating cap, a muffle with a central dead-end pipe, a pipeline for supplying a cooler installed in a dead-end pipe, characterized in that, in order to reduce the uneven temperature field in the cross section of the charge and reduce the cooling time, it is equipped with a dead-end pipe the muffle is coaxial to the pipeline with a pipe plugged at one end and with a support ring on the other end, while the support ring is placed on the muffle and has radial ribs that form between Internal surface of the support ring and muffle channels. 2. Bake pop. 1, which differs from I in that the lower end of the pipeline is separated from the bottom of the additional pipe at a distance of 0.2–1.0 in diameter of the pipe.