JP6320182B2 - Heat treatment basket - Google Patents

Description

  The present invention relates to an improvement in a heat treatment basket that can be used as a container for a plurality of workpieces when heat-treating a plurality of workpieces in a batch-type heat treatment furnace.

  Various metal products are subjected to heat treatment for obtaining desired mechanical properties as necessary. The heat treatment furnace used at this time is roughly divided into a batch type and a continuous type. Although the batch-type heat treatment furnace is inferior in productivity to the continuous heat treatment furnace, there is an advantage that it is easy to set optimum heat treatment conditions for each of various metal products.

When heat treatment is performed in a batch-type heat treatment furnace, for example, a plurality of workpieces (metal products to be heat-treated) are heated and rapidly cooled in a flow as shown in FIGS.
That is, first, as shown to (A), the basket 1 (for example, refer patent document 1) which accommodated the some workpiece | work is introduce | transduced in the introduction chamber 2. As shown in FIG. Next, as shown in (B), the door 4 of the heating chamber 3 existing on the side of the introduction chamber 2 is opened, and the basket 1 is placed in the heating chamber 3. Next, as shown in (C), the door 4 of the heating chamber 3 is closed, and the workpieces accommodated in the basket 1 are set in the heating chamber 3 to be higher than the transformation points of the workpieces. Heat to temperature. Thereafter, as shown in (D), the door 4 of the heating chamber 3 is opened, and the basket 1 is taken out from the heating chamber 3. Then, the basket 1 is placed on an elevator 5 that has been raised into the introduction chamber 2. Next, as shown in (E), the elevator 5 is lowered and the basket 1 is submerged in the coolant (oil) 7 in the cooling tank 6 existing below the introduction chamber 2. Thereby, each said workpiece | work accommodated in this basket 1 is rapidly cooled (quenching) by immersing each said workpiece | work in the said cooling fluid 7. FIG.

  In the heat treatment performed in the batch-type heat treatment furnace as described above, the basket 1 is removed from the heating chamber 3 and submerged in the coolant 7 to some extent (for example, 25 to 30 seconds). Time). Further, there is no heating source in the introduction chamber 2 through which the basket 1 passes. Furthermore, the basket 1 generally used from the past is a stainless steel bowl-shaped container having an open upper end, and has a small heat capacity, and therefore has poor heat retention performance for each workpiece. For this reason, in the meantime, the temperature of each of these workpieces gradually decreases. In particular, when each of these workpieces has a small mass or thickness, i.e., has a small amount of heat held by itself, the amount of temperature decrease during that time increases, so the temperature drops below the transformation point, There is a possibility that proper quenching cannot be performed (quenching is incomplete). For this reason, conventionally, workpieces that may cause such inconvenience have been heat treated in a continuous heat treatment furnace that can be quickly cooled immediately after heating without being heat treated in a batch heat treatment furnace. It was.

  However, batch-type heat treatment furnaces have characteristics such as easier setting of optimum heat treatment conditions for each type of metal product compared to continuous heat treatment furnaces. However, it is desirable that heat treatment can be performed in a batch heat treatment furnace as necessary.

JP 2000-273527 A

  In view of the circumstances as described above, the present invention realizes a heat treatment basket capable of preventing incomplete quenching of a workpiece when performing heat treatment of a workpiece having a small mass or thickness in a batch heat treatment furnace. Invented as much as possible.

The heat treatment basket of the present invention is placed in a heating chamber together with the workpiece, which is a metal product to be heat-treated, heated to a predetermined temperature in the heating chamber, and then taken out of the heating chamber. And immersed in the coolant.
In particular, the heat treatment basket according to the present invention has a storage portion that can store the workpiece, and is a heat insulating member that is disposed at a position that surrounds the periphery of the storage portion with respect to the horizontal direction, and a position that sandwiches the storage portion from above and below. A material (a heat retaining member separate from a basket portion as a container and a partition provided as necessary to partition the internal space of the basket portion) is provided.
In addition, as this heat insulating material, it can employ | adopt metal things, such as steel, which can suppress that the temperature of the said workpiece | work falls by the heat | fever stored in self by being heated in the said heating chamber.

When the heat treatment basket according to the present invention is implemented, for example, as in the invention described in claim 2, a plurality of main baskets stacked in the vertical direction and the whole of the plurality of main baskets are arranged on both sides in the vertical direction. And a pair of sub-baskets arranged at positions sandwiched between the two. And each said main basket shall have the said accommodating part, respectively, and shall hold | maintain the said heat insulating material in the position surrounding the circumference | surroundings of this accommodating part regarding a horizontal direction. In addition, it is assumed that each of the sub-baskets holds the heat insulating material at a position where it overlaps in the vertical direction with respect to the storage portion of each of the main baskets.
When carrying out the invention described in claim 2 as described above, for example, as in the invention described in claim 3, in addition to the position where the entirety of the plurality of main baskets is sandwiched from both sides in the vertical direction, The sub-basket can be arranged at a position sandwiched between at least one pair of adjacent main baskets.

  In the case of the heat treatment basket of the present invention configured as described above, the temperature of the workpiece decreases in the batch type heat treatment furnace until it is taken out of the heating chamber and placed in the coolant. It is suppressed by the heat insulation effect by the heat insulation material. In particular, in the case of the present invention, since the heat insulating material is disposed at a position surrounding the periphery of the accommodating portion of the workpiece in the horizontal direction and a position sandwiching the accommodating portion from both the upper and lower sides, The effect can be increased. Therefore, even when the mass or thickness of the workpiece is small, the workpiece can be put into the coolant while maintaining the heating temperature in the heating chamber. As a result, it is possible to prevent incomplete quenching of the workpiece.

Sectional drawing of the basket for heat processing which accommodated the some workpiece | work corresponding to the aa cross section of FIG. 2, which shows one example of embodiment of this invention. The top view which looked at the subbasket from the upper part of FIG. The top view which looked at the main basket which accommodated the workpiece | work from the upper direction of FIG. The schematic diagram which showed the condition which processes a heating and rapid cooling with respect to the some workpiece | work accommodated in the basket in a batch type heat processing furnace in order of a process.

  An example of an embodiment of the present invention will be described with reference to FIGS. The heat treatment basket 19 of this example can be used as a container for each work when heat treatment is performed on a plurality of works in a batch heat treatment furnace as shown in FIG.

  In such a heat treatment basket 19 of this example, as shown in FIG. 1, a plurality (eight) of main baskets 8, 8 and a plurality (three) of sub-baskets 9, 9 are stacked in the vertical direction. It consists of Specifically, a pair of main baskets 8, 8 adjacent to each other in the vertical direction at a position where the whole of the plurality of main baskets 8, 8 stacked in the vertical direction is sandwiched from both sides in the vertical direction and at the center in the vertical direction. The sub-baskets 9 are arranged one by one at a total of three positions including the positions sandwiched between them.

Each of the main baskets 8 and 8 includes a main basket element 10 and a plurality of heat insulating materials 11 and 11.
Of these, the main basket element 10 is a shallow bowl-shaped container made of a heat-resistant metal such as stainless steel or titanium and having an open top, as shown in FIG. Is a rectangle. Such a main basket element 10 has a rectangular bottom portion 12 and a peripheral wall portion 13 provided so as to extend upward from the outer peripheral edge portion of the bottom portion 12. The bottom portion 12 and the peripheral wall portion 13 are configured by appropriately combining a metal having a heat resistance as described above, a frame material, a wire mesh, a punching metal, and the like (a liquid such as a cooling liquid can pass through). A grid-like frame structure, a network structure, a porous structure, etc.). In addition, the said surrounding wall part 13 may be not a wall shape but a vertical grid | lattice form (The circumferential direction space | interval of a pillar is arbitrary). Further, the peripheral wall portion 13 can be formed in a plate shape having no liquid passage structure.

  Further, as shown in FIG. 3, a housing portion 14 is provided in the center of the main basket element 10. In the case of the illustrated example, the accommodating portion 14 is divided into two by a partition 15a provided in the center portion in the longitudinal direction (left-right direction in FIG. 3), and partitions 15b and 15b provided at both end portions in the longitudinal direction. Thus, a part of the boundary with the surrounding portion is partitioned. Each of these partitions 15a and 15b is configured so as to have a simple plate shape or a liquid passing structure by using the same metal as the bottom portion 12 and the peripheral wall portion 13.

  In addition, an appropriate number of the heat insulating materials 11 and 11 are arranged on the outer periphery of the main basket element 10 that surrounds the storage portion 14 in the horizontal direction. In the case of this example, these heat insulating materials 11 and 11 are steel round bars or square bars.

  A plurality of workpieces 16 and 16 are accommodated in the accommodating portion 14 during use. 1 and 3, each of these workpieces 16 and 16 is conceptually shown. Actually, a smaller appropriate number of workpieces are located at the positions of the workpieces 16 and 16 shown in FIGS. 1 and 3. They are arranged so that they are not closely aligned (there may be some contact portions, but a moderate gap is formed in the remaining portions). The reason for adopting such an arrangement mode is to prevent the phenomenon that the workpieces 16, 16 blow up when they are put into the coolant. In the case of this example, for the same reason, the heat insulating materials 11 are also arranged so as not to be closely aligned.

Each of the sub-baskets 9 and 9 includes a sub-basket element 17 and a plurality of heat insulating materials 11 and 11.
Of these, the sub-basket element 17 has the same configuration as the main basket element 10 except that it does not include the partitions 15b and 15b. As shown in FIG. 2, the sub-basket element 17 includes a central portion that overlaps with the accommodating portion 14 of each of the main basket elements 10 and 10 in the vertical direction. 11 and 11 are arranged in an appropriate number so as not to be closely aligned. The work 16 is not accommodated in the sub-basket element 17 even during use.

  When the present invention is carried out, the same auxiliary basket element 17 as the main basket element 10 can be used. In this case, an appropriate number of the heat insulating materials 11 and 11 are arranged in the portion corresponding to the accommodating portion 14 of the main basket element 10 (the portion surrounded by the partitions 15b and 15b) in the sub basket element 17. (Further, an appropriate number of heat insulating materials 11 and 11 may be arranged in the remaining portion).

In the case of this example, between the basket elements 10 and 17 (or 10, 10) adjacent in the vertical direction, the basket elements 10 and 17 (or 10, 10) may be displaced in the horizontal direction. An engagement structure is provided to prevent this. As such an engagement structure, for example, of basket elements 10 and 17 (or 10, 10) adjacent in the vertical direction, the lower end portion of the upper basket element is fitted to the upper end portion of the lower basket element. A structure or a structure in which an engaging portion provided in at least one basket element is engaged with the counterpart basket element can be employed.
Further, as shown in FIG. 1, the heat treatment basket 19 of this example is carried in a batch-type heat treatment furnace (see FIG. 4) together with the substrate 18 while being supported on the heat-resistant substrate 18. And move in the heat treatment furnace.

  In the case of the heat treatment basket 19 of the present example configured as described above, in the batch-type heat treatment furnace (see FIG. 4), the heat treatment basket 19 is taken out from the heating chamber 3 and placed in the coolant 7. It is possible to suppress a decrease in the temperature of each of the workpieces 16 and 16 by the heat retaining effect of the heat retaining materials 11 and 11. That is, it is possible to suppress the temperature of each of the workpieces 16 and 16 from being lowered by the heat of the heat insulating materials 11 and 11 heated to the same temperature as that of the workpieces 16 and 16 in the heating chamber 3. In particular, in the case of this example, each of these heat insulating materials 11 and 11 surrounds the periphery of each of the storage portions 14 and 14 with respect to the horizontal direction, and a position that sandwiches the storage portions 14 and 14 from both the upper and lower sides. Has been placed. Furthermore, the sub-basket 9 containing only the heat insulating materials 11 and 11 is provided not only at the uppermost part and the lowermost part but also at the central part in the vertical direction. For this reason, the heat retention effect of each said workpiece | work 16 and 16 can be made high. Therefore, these workpieces 16 and 16 can be put into the cooling liquid 7 while maintaining the heating temperature in the heating chamber 3 substantially. As a result, it is possible to prevent the workpieces 16 and 16 from being incompletely quenched.

In the case of the heat treatment basket 19 of this example, since the basket elements 10 and 17 and the partitions 15a and 15b are also made of metal, the members 10, 17, 15a and 15b are also formed in the heating chamber 3. The heat-retaining effect for each of the workpieces 16 and 16 is exhibited by the heat stored in itself by being heated.
However, each of these members 10, 17, 15a, 15b has a small heat capacity and has a liquid passage structure or a thin-walled structure, so that it is easily cooled. Therefore, the temperature drop of the workpieces 16 and 16 cannot be sufficiently suppressed only by the heat retaining effect of the members 10, 17, 15 a and 15 b.
Therefore, in the case of the heat treatment basket 19 of this example, each of the heat insulating materials 11 is provided at a position surrounding the accommodating portions 14 and 14 of the workpieces 16 and 16 separately from the members 10, 17, 15 a and 15 b. , 11 can sufficiently suppress the temperature drop of each of the workpieces 16, 16.

When implementing the present invention, the number of main baskets and sub-baskets can be appropriately selected as long as the requirements described in the claims are satisfied.
In addition, regarding the heat insulating material, an appropriate material, shape, size, number, etc. can be adopted. For example, the shape of the heat insulating material is not limited to the rod shape as shown in FIGS. 1 to 3, and various shapes such as a block shape can be adopted.
Further, in order to maintain the state in which the heat insulating materials are arranged at positions that surround the periphery of the storage portion in the horizontal direction and at positions that sandwich the storage portion from both the upper and lower sides, It can also be fixed to the sub-basket element by tying it with a heat-resistant wire. However, if the state is maintained when the heat treatment is performed, each of the heat insulating materials does not need to be fixed to the main basket element or the sub basket element. You may slide or roll inside.
Moreover, it is not necessary to provide a partition inside the main basket element and the sub basket element. However, when a partition is provided, an appropriate arrangement configuration or the like can be adopted even for the partition. For example, the inside of the main basket element or the sub basket element may be finely divided by a plurality of partitions according to the shape, size, number, etc. of the work and the heat insulating material. Moreover, you may make it surround the perimeter of an accommodating part with a partition.
In addition, a plurality of handles can be provided on the peripheral wall portions of the main basket element and the sub basket element so as to be separated in the circumferential direction. In this case, each of these handles can be used as an engaging portion for preventing horizontal displacement between basket elements adjacent in the vertical direction.
The heat treatment basket of the present invention can be used for various heat treatments in which the temperature of the workpiece may decrease between the heating process and the cooling process.

DESCRIPTION OF SYMBOLS 1 Basket 2 Introduction chamber 3 Heating chamber 4 Door 5 Elevator 6 Cooling tank 7 Coolant 8 Main basket 9 Sub basket 10 Main basket element 11 Insulating material 12 Bottom 13 Peripheral wall 14 Storage section 15a, 15b Partition 16 Work 17 Sub basket element 18 Substrate 19 Heat treatment basket

Claims (3)

The workpiece, which is a metal product to be heat-treated, is placed in the heating chamber together with the workpiece, heated to a predetermined temperature in the heating chamber, then taken out of the heating chamber and immersed in the coolant. A heat treatment basket,
For heat treatment, comprising: a storage section that can store the workpiece; and a heat insulating material disposed at a position surrounding the storage section in the horizontal direction and a position sandwiching the storage section from the upper and lower sides. basket. A plurality of main baskets stacked in the vertical direction, and a pair of sub-baskets disposed at positions sandwiching the whole of the plurality of main baskets from both sides in the vertical direction,
Each of the main baskets has the storage portion, and holds the heat insulating material at a position surrounding the periphery of the storage portion in the horizontal direction.
Each of the sub-baskets holds the heat insulating material at a position overlapping in the vertical direction with respect to the storage portion of each of the main baskets.
The heat treatment basket according to claim 1. In addition to a position where the whole of the plurality of main baskets is sandwiched from both sides in the up-down direction, the sub-basket is also disposed at a position sandwiched between at least one pair of main baskets adjacent in the up-down direction. Item 3. The heat treatment basket according to Item 2.

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