JP3008388B2 - Continuous heat treatment equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous heat treatment apparatus,
More specifically, quenching, normalizing, annealing, etc.
These heat treatments other than the quenching treatment are also referred to as other heat treatments).

[0002]

2. Description of the Related Art Conventionally, as a continuous heat treatment apparatus for performing quenching treatment and other heat treatment on an article to be heat treated while also serving as a heating furnace, a high-temperature furnace on the upstream side and a low-temperature furnace on the downstream side are transported in two vertical stages. A first elevator having two stages, an oil quenching tank disposed below the high-temperature furnace and the transfer device, is connected between the transfer device and the low-temperature furnace. A vehicle equipped with a two-stage second elevator is used.

In the conventional continuous heat treatment apparatus described above, when quenching is performed on a heat-treated product, 1) the heat-treated product is subjected to a predetermined heat treatment in a high-temperature furnace → 2) the heat-treated product is raised from the high-temperature furnace. Load the lower part of the first elevator → 3) Lower the first elevator and load the heat-treated product into the oil quenching tank → 4) Raise the first elevator and move the heat-treated product to the first Transfer from the lower part of the elevator to the lower part of the transfer device → 5) Transfer the article to be heat-treated at the lower part of the transfer device → 6) Transfer the object to be heat-treated from the lower part of the transfer device to the lower part of the second elevator that is in the ascending state → 7) Loading the article to be heat-treated into the low-temperature furnace from the lower stage of the second elevator → 8) Predetermining heat treatment of the article to be heat-treated in the low-temperature furnace, and quenching the article to be heat-treated by the above procedure. Things.

In the conventional continuous heat treatment apparatus, when performing another heat treatment on the heat-treated product, 1) the heat-treated product is subjected to a predetermined heat treatment in a high-temperature furnace → 2) the heat-treated product is lowered from the high-temperature furnace. 3) Transfer the article to be heat-treated from the upper section of the first elevator to the upper section of the transfer device → 3) Ascend the first elevator, and 4) transfer the article to be heat-treated to the upper section of the transfer apparatus. Transfer at the upper stage → 5) Transfer the article to be heat-treated from the upper stage of the transfer device to the upper stage of the second elevator ascending → 6) Lower the second elevator and move the object to be heat-treated from the upper stage of the second elevator. 7) The heat-treated product is subjected to a predetermined heat treatment in the low-temperature furnace, and another heat treatment is performed on the heat-treated product in the above procedure.

[0005] However, in the conventional continuous heat treatment apparatus described above, oil smoke generated when the article to be heat treated discharged from the high-temperature furnace to the lower stage of the first elevator is charged into the oil quenching tank is generated by the first elevator. The oil smoke scatters and adheres to the upper stage and further to the upper stage of the transfer device, and has a disadvantage that the attached oil smoke has an adverse effect on the heat-treated product to be subjected to other heat treatment via these upper stages. The disadvantage is that frequent cleaning operations are required to remove the dust.

[0006]

The problem to be solved by the present invention occurs violently during the quenching process of the article to be heat-treated, and scatters to the upper stage of the first elevator and further to the upper stage of the transfer device. The attached oil fume has an adverse effect on the heat-treated product to be subjected to other heat treatments via these upper stages, and a troublesome cleaning operation for removing the attached oil fume is frequently required.

[0007]

SUMMARY OF THE INVENTION The present invention is directed to a continuous heat treatment apparatus for performing both quenching and other heat treatments, and comprises a two-stage upper and lower stage provided on a furnace exterior side of a high-temperature furnace. A first elevator, a two-stage upper and lower second elevator provided on the furnace exterior entrance side of the low-temperature furnace, and a two-stage upper and lower transfer device interposed between the first elevator and the second elevator. A shelf plate is laid on an upper stage of the first elevator in which an oil quenching tank is disposed below, and the first elevator is sealed with a hood having an opening and closing door in two upper and lower stages, A projecting piece is provided on the inner surface of the
When the elevator is raised, the upper edge of the shelf comes into contact with the upper projection, and when the first elevator is lowered, the lower edge of the shelf comes into contact with the lower projection. According to the present invention.

An important point in the present invention is that an upper and lower two-stage first elevator having a shelf board laid thereon is sealed by a hood having an upper and lower two-stage opening / closing door, and the first elevator is lifted and lowered when the first elevator is moved up and down. The shelf plate is in a place where it comes into contact with projecting pieces provided in two upper and lower stages on the inner side surface of the hood to separate the upper stage and the lower stage of the first elevator.

[0009]

The quenching process itself and the other heat treatment process of the article to be heat-treated by the continuous heat treatment apparatus according to the present invention are performed by opening and closing the upper and lower two-stage doors mounted on the hood that seals the first elevator. Is the same as that of the conventional continuous heat treatment apparatus described above, but in the continuous heat treatment apparatus according to the present invention, when performing the quenching treatment on the heat-treated product, the first elevator is lowered to lower the heat-treated product. Is charged into the quenching tank, the shelf of the first elevator abuts against the lower projecting piece of the hood to separate the upper and lower stages of the first elevator, and the first elevator is lifted to raise the first elevator. When the article to be heat-treated is loaded from the quenching tank, the shelf of the first elevator comes into contact with the upper projecting piece of the hood to separate the upper and lower stages of the first elevator.

[0010] Therefore, according to the present invention, it is possible to suppress oil fumes that are violently generated during the quenching treatment of the heat-treated product from scattering and adhering to the upper stage of the first elevator and further to the upper stage of the transport device. As a result, it is possible to remarkably reduce the adverse effect of the oil smoke on the heat-treated product subjected to other heat treatments via these upper stages and the troublesome cleaning work for removing the oil smoke.

In the present invention, not only oil fumes that are violently generated during the quenching treatment of the article to be heat-treated are prevented from scattering and adhering to the upper stage of the first elevator and further to the upper stage of the transporting device, and also to prevent high temperature. In order to prevent the danger of fire that may occur when the heat-treated article is charged into the quenching tank, a non-combustible gas supply pipe is connected to a space enclosed by the hood of the first elevator. When the high-temperature article to be heat-treated is charged into the quenching tank, the amount of non-combustible gas, for example, N ₂ gas, DX gas, NX gas, or residual oxygen gas is reduced into the space through the non-combustible gas supply pipe. It is preferable to supply combustion exhaust gas or the like.

Further, in the present invention, some of the oily fumes which are violently generated during the quenching treatment of the heat-treated product and which may leak to the transfer device are subjected to another heat treatment via the transfer device. In order to prevent adverse effects on the heat-treated product, the transfer device is sealed with surrounding means, for example, a hood or an air curtain, and the sealed space is connected to a smoke collection facility to reduce leaked oil smoke. It is preferable to discharge the gas to the outside of the system by using the smoke collecting facility.

[0013]

FIG. 1 is a plan view schematically showing an embodiment of the present invention.
FIG. 2 is a partially enlarged longitudinal sectional view showing one embodiment of FIG.

In FIG. 1, a high-temperature furnace 11 is arranged on the upstream side, and a low-temperature furnace 12 is arranged on the downstream side. An upper and lower two-stage first elevator 21 is provided at the furnace exterior side of the high temperature furnace 11, and an upper and lower two-stage second elevator 22 is provided at the furnace exterior side of the low temperature furnace 12. Between the first elevator 21 and the second elevator 22, two upper and lower transfer devices 23 are interposed. The first elevator 21 is sealed with a hood 31, and the transport device 23 is also sealed with a hood 32, and the hood 32 is connected to a smoke collection facility 41.

In FIG. 2, an oil quenching tank 51 is arranged below the upper and lower first elevators 21, and the first elevator 21 extends over the oil quenching tank 51 and the discharge side of the high-temperature furnace 11. It is sealed with a hood 31.

The hood 31 has an up and down 2
Step opening / closing doors 61 and 62 are provided.
Protrusions 71 and 72 are provided on the inner side surface of the hood 31 slightly lower than 62 in two vertical stages, and a noncombustible gas supply pipe 42 is provided in the hood 31 further below the protruding piece 72. The non-combustible gas supply pipe 42 is connected to a non-combustible gas supply source 43.

In the upper stage of the first elevator 21 in the upper and lower stages, the upper edge of the first elevator 21 comes into contact with the upper projecting piece 71 when the first elevator 21 rises, and the lower edge of the first elevator 21 descends when the first elevator 21 descends. A shelf plate 81 abutting on the lower projecting piece 72 is laid. FIG. 2 shows a state when the first elevator 21 is ascending, and in this state, the first elevator 21
The upper part is a hood 31, an opening / closing door 61, a projecting piece 71 and a shelf 8
1 is defined from the lower stage. The details of the operation are as described above.

[0018]

As is clear from the above, according to the present invention described above, the oil smoke which is violently generated during the quenching treatment of the article to be heat-treated is scattered to the upper stage of the first elevator and further to the upper stage of the transfer device. As a result, it is possible to significantly reduce the adverse effect of the soot on the heat-treated product subjected to other heat treatment via these upper stages and the troublesome cleaning work for removing the soot. There is an effect that can be.

[Brief description of the drawings]

FIG. 1 is a plan view schematically showing an embodiment of the present invention.

FIG. 2 is a partially enlarged longitudinal sectional view showing one embodiment of FIG. 1;

[Explanation of symbols]

11 ... high temperature furnace, 12 ... low temperature furnace, 21 ... first
Elevator, 22 ... Second elevator, 23 ... Conveying device, 31, 32 ... Hood, 51 ... Oil quenching tank, 61,62 ... Opening door, 71,72 ... Protrusion Piece,
81 ・ ・ ・ Shelves

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C21D 1/18 C21D 1/63 F27B 9/00-9/40

Claims (3)

(57) [Claims] 1. A continuous heat treatment apparatus for performing both quenching treatment and other heat treatment, comprising: a first elevator having two stages, upper and lower, provided on a furnace exterior side of a high-temperature furnace; It has an upper and lower two-stage second elevator installed on the entrance side, and an upper and lower two-stage transfer device interposed between the first elevator and the second elevator, and an oil quenching tank is disposed below. A shelf board is laid on the upper stage of the first elevator,
The first elevator is hermetically sealed by a hood having an opening / closing door in two upper and lower stages, and a protruding piece is provided on the inner surface of the hood in two upper and lower stages. A continuous heat treatment apparatus wherein an edge portion abuts on the upper projecting piece, and a lower edge portion of the shelf comes into contact with the lower projecting piece when the first elevator is lowered. 2. A non-combustible gas supply pipe is provided in a space enclosed by a hood of a first elevator, and the non-combustible gas supply pipe is inserted into the space during a quenching process of a heat-treated article placed in a lower stage of the first elevator. 2. The continuous heat treatment apparatus according to claim 1, wherein the non-flammable gas is supplied through a non-flammable gas supply pipe. 3. The apparatus according to claim 1, wherein the upper and lower transfer devices are sealed by surrounding means, and the hood is connected to a smoke collecting facility.
Or the continuous heat treatment apparatus according to 2.