JPS6314047B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a direct heat treatment apparatus for producing wire rods by hot rolling.

(Prior technology) Direct heat treatment using the heat retained in hot-rolled wire rods involves two methods: quenching a wire coil made by winding the wire into a bundle in a cooling tank, and quenching the center of the wire ring by a certain pitch. There is a method of making it into a loose coil and quenching it in a cooling tank. In the former method, the wire rods closely overlap each other in the coiled state, resulting in insufficient cooling and no effect. On the other hand, in the latter method, by shifting the center of the wire ring by a certain pitch, the wire coil can be brought into a state similar to a single wire, and almost the entire wire coil can be heat-treated.
For this reason, direct heat treatment using the latter method has become common in recent years, and examples thereof are shown below.

JP-A No. 58-3930 and JP-A No. 58-45331 are both related to applications filed by the applicant of the present invention, in which a wire ring is formed into a loose coil with its center shifted by a certain pitch in a cooling tank. It is cooled while being continuously conveyed by a conveyor. The cooling medium supply nozzles are both installed at the bottom of the tank, below the wire rod conveyor, and the supplied refrigerant mainly passes through the bottom of the conveyor, ascends the facing side wall, and circulates to the top. It has a form that makes contact with the wire. The disadvantages of this method are that the overlapping parts of the loose coils cool down more slowly than other parts, and depending on the shape of the lower plate and side guides that support the conveyor in the cooling tank, it is difficult for the supplied refrigerant to reach the upper wire. That's what happens.

(Object of the Invention) The present invention has been made to solve the above-mentioned problems.

(Structure and operation of the invention) The present invention provides a heat treatment apparatus for directly heat-treating a loose coiled wire rod obtained by shifting a hot wire rod by a certain pitch after finishing rolling. A cooling medium supply nozzle is used in equipment that continuously quenches the heated wire rod by winding it into a loose coil while continuously dropping it onto a dry conveyor and dropping it into a cooling tank with a wet conveyor installed on the lower plate. Attach the nozzle to the top of the cooling tank in a direction perpendicular to the conveyor so that the tip of the nozzle enters the cooling medium, and the angle at which the cooling medium is jetted from the nozzle ranges from vertical to horizontal. is installed in a position where it is uniformly hardened, and the arrangement of multiple nozzles is
This heat treatment equipment places many nozzles in the hot part of the coil near where the loose coil has fallen into the cooling tank, and fewer nozzles are placed in the rear part where the loose coil is transported by a wet conveyor, thereby enabling rapid cooling.

(Example) The present invention will be described in more detail below based on an example based on the drawings.

In FIGS. 1, 2, and 3, FIG. 1 is an explanatory view showing a wire continuous quenching heat treatment facility, and FIGS. 2 and 3 are explanatory views showing a cross section of a cooling tank.

After the hot rolled wire rod 2 is continuously formed into a ring shape in the laying head 1, the entire wire rod 2 falls onto a horizontally movable dry conveyor 3, is conveyed, and then falls into a heat treatment device 5. A cooling medium 4 is stored therein, and a wet conveyor 7 on which the continuous ring-shaped wire 2 is placed and conveyed is provided on a lower plate 6 in the lower part of the inside thereof. During the process, it is continuously quenched in a cooling tank 5. In addition, the cooling medium injection nozzle 9 into the cooling tank 5 is arranged at the upper part of the cooling tank 5 in a direction perpendicular to the traveling direction of the wet conveyor 7.
The cooling medium is injected from the nozzle 9, stirred and mixed inside the tank, and then discharged from the discharge port 10.The angle at which the cooling medium is ejected from the nozzle is set to the lower plate 6 having the side guides 8, as shown in FIG. On the other hand, the cooling bath 5 is installed at a position where the inside of the cooling tank 5 is completely stirred and mixed in a range from near the vertical direction to near the horizontal direction as shown in FIG. 3, so that the wire is uniform and sufficiently quenched. As means for changing the nozzle angle, a known method may be used, for example, a means for rotating the nozzle around a fulcrum 9' as shown in FIGS. 2 and 3.

Here, it is important to arrange the plurality of nozzles so that the hot wire 2 that has fallen into the cooling tank 5 is cooled uniformly and below a predetermined temperature in the high temperature part of the wire near the drop opening. In order to supply a large amount of the cooling medium 5 to the high temperature part of the wire rod, and to supply the cooling medium necessary to satisfy the heat balance or the minimum stirring condition to the low temperature part of the wire rod, a plurality of nozzles are arranged in large numbers in the high temperature part of the wire coil, Place fewer nozzles in the low temperature area.

Also, the installation position of the cooling medium outlet 10 will be described. In the cooling tank 5, it is necessary to completely bury the wire 2 and keep the depth of the cooling medium 4 constant. In order for a large amount of the cooling medium supplied upstream of the wet conveyor, which is the high-temperature part of the wire, to flow downstream of the wet conveyor and work effectively for cooling, it is necessary to
0 is better installed downstream of wet conveyor 7.
The amount of cooling medium can be reduced compared to installing it upstream, and since the temperature of the cooling medium in the cooling tank is lower in the high temperature portion of the wire, the cooling rate can be high, which is desirable in terms of quality.

(Effects of the Invention) As described above, by using the present invention, in equipment for continuous quenching of wire rods, it becomes possible to continuously perform quenching treatment that uniformly and rapidly cools the entire wire rod with a small amount of cooling medium used. In particular, a structure in which the inside of the tank is divided into a lower part and an upper part, such as the case where the side guide 8 is connected to the lower plate 6 and connected to the side wall of the heat treatment equipment as shown in FIGS. 2 and 3, etc. It is effective for

[Brief explanation of the drawing]

FIG. 1 is a side view of the entire heat treatment apparatus, and FIGS. 2 and 3 are two examples of cross-sectional views taken along the line AA in FIG. 1. 1... Laying head, 2... Rolled wire rod, 3
... Dry conveyor, 4 ... Cooling medium, 5 ... Heat treatment device, 6 ... Lower plate, 7 ... Wet conveyor, 8 ... Side guide, 9 ... Nozzle,
10... Drain port.

Claims (1)

[Claims] 1. In a continuous heat treatment device in which the wire after finish rolling is made into a loose coil with the center of the ring shifted by a certain pitch and dropped into a cooling tank having a wire transport device on the lower plate, a plurality of cooling medium supply nozzles are connected at the top of the cooling tank. A wire heat treatment apparatus characterized in that the tip thereof is attached by being immersed in a cooling medium, and the nozzle angle is variable in a range from vertical to horizontal.