JPS6026126Y2 - Tube heat treatment equipment - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a heat treatment apparatus for pipe bodies such as cast iron pipes.

As a heat treatment for cast iron pipes, there is a method in which a desired ferrite structure is obtained by raising the pipe body to a certain temperature and then slowly cooling it at a predetermined cooling rate.

Conventionally, continuous furnaces have been used for this heat treatment, in which the pipes are heated and slowly cooled while being transported with their axes horizontal. It is difficult to create a large temperature gradient, requiring a fairly long distance, and the width is wide, so a large space is required.

Also, because the space was large, heat loss was also large.

On the other hand, batch type furnaces have also been used, but they have been inefficient.

The present invention solves the above problems by making the furnace body approximately U-shaped in plan view and transporting the tube body while vertically suspending and supporting it, allowing efficient processing in a small space. The present invention provides a tube heat treatment apparatus that prevents deformation due to high temperatures during heat treatment by rotating the tube around the tube axis.

An embodiment of the present invention will be described below based on the drawings.

Reference numeral 1 denotes a furnace body having a substantially U-shape in plan view, and has a tube inlet 2 at one end 1a adjacent to each other and a tube outlet (not shown) at the other end 1b.

The furnace body 1 has a height greater than the length of the tube so that the tube P to be heat treated can be vertically suspended and transferred.

Further, the area between the folded part 3 and one end 1a of the furnace body 1 constitutes a heating area 4, and the area between the folded part 3 and the other end 1b constitutes a slow cooling area 5. A heating burner (not shown) is appropriately provided on the side wall.

Preferably, the folded portion 3 is provided with an opening/closing door that opens when the tube P passes through.

An annular guide rail 6 is arranged on the upper surface of the furnace body 1 along the planar shape of the furnace body 1, and a plurality of carts 7 movable along the guide rail 6 are arranged.

Although only two carts are shown in the figure, in reality, many carts are connected in a ring with appropriate intervals between each cart, and one or more of them A displacement drive 8 is provided.

As shown in FIG. 2, a rotating shaft 9 that extends into the furnace body 1 through the earthen wall of the furnace body 1 is suspended from each cart 7, and one end of the pipe P is attached to the lower end of the rotating shaft 9. A gripping portion 10 is provided for gripping.

Reference numeral 11 denotes a rotation drive device for the rotating shaft 9, which is installed on the cart 7.

The rotary shaft 9, the grip portion 10, and the rotation drive device 11 constitute a rotary grip device.

12 is a rotating shaft 9 passing slit formed on the upper wall of the furnace body 1;
13 is a slit shielding plate.

The gripping portion 10 consists of a support plate 14 attached to the lower end of the rotating shaft 9 and a large number of engagement arms 16 attached rotatably in the radial direction via an outer peripheral bracket 16 of the support plate 14. An engaging member 17 that engages with the back surface of the flange at one end of the tube body P or the shoulder of the socket is provided at the tip of the tube body P.

The engaging arm 16 is rotated by an appropriate means (not shown) such as a cylinder device between a posture in which it grips the tube P as shown in the figure and a posture in which it rotates in the radial direction to release the tube P. Ru.

Note that the earth wall of the furnace body 1 may be omitted, and the cart 7 may also serve as the earth wall of the furnace body 1.

Further, instead of providing the movable drive device 8 on the cart 7, a pressing device may be provided on the furnace body 1 side to press the cart 7 and drive it to move.

Next, to explain the operation, the tube P pulled out from the centrifugal casting machine (not shown) is vertically erected by the tube tilting device installed near the tube entrance 2, and then moved from the tube body 2 into the furnace body 1. The tube is inserted into the tube, is gripped and suspended by a gripping part 10 of a rotary gripping device provided on the cart 7, and is rotated around the tube axis by a rotary drive device 11.

In this state, while the cart 7 moves through the heating area 4 of the furnace body 1, it is heated to a predetermined temperature and maintained at that temperature.

Thereafter, while passing through the folding section 3 and moving through the annealing region 5, the tube P is slowly cooled at a predetermined cooling rate and the heat treatment is completed.When it reaches the waist tube outlet, the tube P is removed from the gripping section 10 and taken out from the furnace body 1. Thereafter, the tube is turned sideways by a tube tilting device and transferred to the next process using a wheel stand or the like as appropriate.

Since the tube P is rotated around the tube axis during the above heat treatment process in the furnace body 1, its cylindrical shape is not deformed.

According to the tubular heat treatment apparatus of the present invention, as is clear from the above description, since the tubular body is continuously heat treated while being vertically erected and transported, the installation area is small and the processing efficiency is high.

Further, since the furnace body is U-shaped and the heating region and slow cooling region are separated by the folded portion, a large thermal gradient can be obtained and the furnace body can be made small.

Furthermore, since the tube is rotated around the tube axis within the furnace chamber during heat treatment, the cylindrical shape of the tube can be reliably maintained regardless of the high temperature treatment.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is an overall perspective view, and FIG. 2 is a longitudinal sectional view. 1...Furnace body, 3...Folding part, 4.
・・・Heating area, 5... Slow cooling area, 6...
...Guide rail, 7...Dolly, 9...
...Rotation axis, 10...Gripping part, 11...
・Rotation drive device.

Claims (1)

[Scope of utility model registration request] A furnace body having a substantially U-shape in plan view is provided, an annular guide path along the furnace body is provided on the furnace body, and a plurality of carts movable along the annular guide path are provided, and the carts are provided with an annular guide path along the furnace body. 1. A tubular body heat treatment apparatus, characterized in that a rotary gripping device is provided for rotatably supporting one end of the tubular body around the axis of the tubular body.