JPS6120611B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for uniformly heat-treating wire rods while conveying them on a conveyor.

The wire may be cooled while being conveyed on a conveyor to impart the required mechanical properties to the wire. For example, in direct patenting, a wire rod rolled by a finishing mill is cooled by a cooling device, formed into a continuous ring shape (hereinafter referred to as a loose coil shape) by a laying cone, and then supplied to a conveyor. Or use water cooling. Through such heat treatment, the wire rod becomes a fine pearlite structure, and a high-strength wire rod with a uniform structure, high ductility and toughness, and excellent cold workability can be obtained.

By the way, when the wire rod is cooled while being formed into a loose coil shape as described above and being conveyed by a conveyor, there is a problem that the wire rod cannot be uniformly cooled using conventional devices. That is, as shown in FIG. 1, overlapping portions 2 of the wire rods occur, and this portion is not sufficiently exposed to cold air or cooling water, resulting in a disadvantage that cooling becomes weak. Further, a part of the wire 1 is always in contact with the conveyor 9 (for example, a chain conveyor), and this contact portion 3 is also weakly cooled in the same way as described above. Such localized weakness in cooling causes the mechanical properties of the wire to be non-uniform along the length of the wire. In particular, when the wire is conveyed at high speed and cooled rapidly, the above-mentioned non-uniformity becomes significant.

Therefore, this invention solves the above-mentioned problems in conventional wire rod heat treatment, and aims to provide a wire rod heat treatment device that can uniformly cool and heat-treat loose coil-shaped wire rods on a conveyor. It is.

Hereinafter, the present invention will be described in detail based on preferred embodiments with reference to the drawings.

FIG. 2 shows an outline of equipment for controlling and cooling the rolled wire rod on a conveyor and subjecting it to heat treatment.
The hard wire rod 1 rolled by the finishing mill 11 is heated to a finishing rolling temperature of 1000 to 1100°C by the cooling device 12.
After being cooled from a temperature range of 950 to 850°C, it is made into a loose coil by a laying cone 13 and conveyed by a conveyor 14. In this process, the wire coil is regulated and cooled by applying a cooling medium such as cold air or cooling water.

In the above-mentioned equipment, the present invention provides conveyor 1
It is applied to part 4. That is, Figures 3 to 5
The figure shows an example of the present invention, in which a set of vertical rolls 16 and 17 facing each other on the left and right is arranged between the transport rolls 15 of a conveyor 14. Vertical roll 1
6 and 17 lightly pinch the wire coil 4 from both sides, and are rotationally driven by a motor 20 in the directions of arrows A and B via speed reducers 18 and 19, respectively. Since the reduction gears 18 and 19 have different reduction ratios, the circumferential speeds of the vertical rolls 16 and 17 are different on the left and right sides. Although various values can be arbitrarily selected for the ratio of the peripheral speeds of the left and right vertical rolls, the average value of both of the vertical rolls must correspond to the conveyor speed. In this way, vertical rolls 16 and 1
By providing a peripheral speed difference between the wire rod 1 and the vertical rolls 16 and 7, these peripheral speeds act additionally on the wire rod 1 due to friction between the wire rod 1 and the vertical rolls 16 and 17. In this example, the vertical roll 16 is rotated at a high speed, and the vertical roll 17 is rotated at a relatively low speed. Therefore, the tangential speed of the wire rod 1 on the vertical roll 16 side is greater than that on the vertical roll 17 side, the wire rod coil 4 is twisted and displaced in the direction of arrow C, and the wire rods 1 are displaced from each other at the overlapped portion 2. .

Further, each of the vertical rolls 16 and 17 is provided with a spiral guide groove 21 on its outer peripheral surface. The width and depth of the guide groove 21 are such that the wire rod 1 can fully enter therein. In addition, the directions of the spirals are opposite to each other on the left and right so as to push the wire coil 4 forward.
In this embodiment, when facing the conveyance direction, the left side is the left-hand thread direction, and the right side is the right-hand thread direction. Therefore, the wire 1 that has entered the guide groove 21 becomes the vertical roller 1.
It is lifted by 6 or 17 rotations and does not overlap with the adjacent wire rods 1. That is, in FIG. 3, the wire 6 is lifted relative to the wire 5, and the two do not overlap at the position P.

Give a tangential velocity difference to the wire coil as described above,
Furthermore, by lifting the wire coil in the spiral guide groove, the wire comes into uniform contact with the cooling medium and is uniformly cooled. To explain the uniformity of cooling in terms of the uniformity of the tensile strength of the wire, if it is rapidly cooled while simply being conveyed by a conveyor as in the past, the tensile strength will increase along the longitudinal direction of the wire by R = 10 to 15 kg/
It varied in the range of mm ² . On the other hand, in the device of this invention, the range of variation in hole tension is R=3.
~5Kg/ ^mm2 .

In addition, in this invention, as mentioned above, the rotational speed of the left and right vertical rolls is changed to give a tangential speed difference to the coil, but instead of this, vertical rolls with different diameters are rotated at the same rotational speed, and the tangential A speed difference may be given.

In addition, in the device of this invention, even if the rotational speed of the left and right vertical rolls is the same, the wire rod coil can be lifted by the spiral guide groove, so a space is created especially in the overlapping portion of the wire rod on both sides of the coil, and uniform cooling is achieved. It is possible to improve

As explained in detail above, the device of the present invention has a spiral guide groove for guiding the wire rod, and is rotationally driven so that the tangential speed on one side of the wire rod coil is higher than the tangential speed on the other side. It is equipped with a vertical roll. This creates vertical gaps at the overlapping portions of the wire rods or the contact portions between the wire rods and the conveyor, and the wire rods are always slightly shifted from each other, so that the cooling water or cold air can be uniformly brought into contact with the wire rods. Therefore, it is possible to uniformly cool the wire along its longitudinal direction, and a wire with uniform mechanical properties can be obtained.

[Brief explanation of the drawing]

Figure 1 is a drawing explaining the problems of the conventional device.
It is a top view of the conveyor which is conveying a wire rod. FIG. 2 is a schematic diagram showing an example of wire processing equipment to which the present invention is applied. 3 to 5 show an example of the device of the present invention, in which FIG. 3 is a plan view thereof, FIG. 4 is a front view, and FIG. 5 is a view taken along arrow A-A' in FIG. be. 1: Wire rod, 2: Overlapping part, 3: Contact part, 4: Wire rod coil, 9, 14: Conveyor, 11: Rolling machine,
12: Cooling device, 13: Laying cone, 15:
Conveyance roller, 16, 17: Vertical roll, 18, 1
9: Reducer, 20: Motor, 21: Guide groove.

Claims (1)

[Claims] 1. A wire heat treatment device comprising: a conveyor that conveys a wire formed into a continuous ring shape; and vertical rolls arranged on both sides of a wire coil and having spiral guide grooves for guiding the wire.