JPS5940432Y2 - Step conveyor for direct heat treatment of hot rolled wire rods - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a step conveyor for direct heat treatment of hot rolled wire rods.

Hot-rolled steel wire is coiled from the winding head of a winding machine and placed on a transfer conveyor installed immediately after.
The wire coils are shifted at regular intervals on the transfer conveyor and transferred while overlapping each other at a rate of 0.1°C/sec.
The method and device (hereinafter referred to as the method) for cooling the wire at an arbitrary cooling rate of ~20°C/see include, for example,
Japanese Patent Publication No. 42-15463 and Japanese Patent Publication No. 51-64416
It is publicly known from the publication No.

However, in the known systems, temperature deviation within the wire coil cannot be sufficiently eliminated due to the high polymerization density of the wire coil, and uniform cooling cannot be achieved stably.

The inventors of the present invention have confirmed through technological development to solve this problem,
A novel method that can perform slow cooling or rapid cooling at any cooling rate is described, for example, in Japanese Patent Application No. 54-116678 (Japanese Unexamined Patent Publication No. 56-41324) entitled "Hot-rolled wire rod cooling method and cooling device". A separate application has been filed.

An outline of this cooling method will be explained based on FIG. 1.

Referring to FIG. 1, 1 is a rolling head of a winding machine installed following a hot rolling mill and cooling device (not shown), and 2 is a rolling head that is continuously fed in a ring shape from the rolling head 1. A roller conveyor on which the wire ring 3 is placed and transferred; 4 is a step conveyor (elevating conveyor) following the roller conveyor 2; 5 is a heat insulation cover that surrounds the wire ring 3 together with the step conveyor 4; The cover 5 is divided into a plurality of zones, and the wire ring 3 passing through the zone is cooled stepwise along a desired cooling curve to undergo transformation.

Further, 6 is a conveyor that transfers the wire ring 3 that has finished cooling after coming out of the heat retaining cover 5, and has an air blast cooling section (not shown) that rapidly cools the ring 3 on the conveyor 6.

7 is a wire convergence device. The wire ring 3 on the stepped conveyor 4 inside the heat insulating cover 5 is transferred in the form of non-concentric, mutually overlapping 9-layer thick coils, and is once stripped off at the stepped portion 8 of the stepped conveyor 40 to form coils on both sides with high coil density. The aim is to remove heat (promote heat radiation) from near the center of the part.

Figure 2 shows the step 8 where the button is pressed on the step roller conveyor 4.
The thick coiled wire rings 3 that have reached the step position fall from the upper conveyor 4a onto the lower conveyor 4b, and at this time, the rings are unraveled one by one and are sprayed with refrigerant (not shown). It is cooled by a refrigerant (air, inert gas, mist, water, etc. whose temperature is higher than the atmospheric temperature or lower than the atmospheric temperature inside the heat insulating cover 5) from the nozzle.

When the wire ring 3 falls, the leading edge of the ring may fall between the collages on the lower conveyor 4b as shown in 3a, which may impede the transfer of the ring.

Since the wire needs to be cooled while being transported at a predetermined speed, such a plunging phenomenon is undesirable because it causes interruption of the line and reduces productivity.

Further, this thrusting phenomenon is one of the factors that causes the shape of the wire ring (wire coil) 3 to become defective, which is undesirable because it affects the quality.

Furthermore, wire rings (wire coils) due to this plunging phenomenon
If the defective shape of 3 occurs, the wire ring (wire coil)
It becomes difficult to make the temperature of No. 3 uniform throughout.

Therefore, if the wire ring 3 is dropped at the step portion 8 of the step conveyor 40 with respect to the falling position of the lower conveyor 4b, the leading edge and the final end of the ring 3 are loosened and dropped at substantially the same falling speed. Difficulties can be resolved.

The present invention was devised by paying attention to the above.

That is, in the present invention, as shown in FIGS. 1, 2, and 4, hot-rolled wire rods are transported in a group of overlapping rings that are shifted at a constant interval, and the temperature is increased from 0.1°C/sec to 2°C.
The conveyor 4a on the upper side of the step part 8
The wire rod ring guiding notch 10 is formed by providing cantilever drive rollers 9 and 9 at the leading end of the transfer, with portions exhibiting a substantially conical shape corresponding to the curvature of the wire rod ring 30 facing each other. , a step conveyor for direct heat treatment of hot rolled wire rods.

As a result, when the wire ring 3 forming the wire coil is uncoiled at the stepped portion 8, the leading end Y and the final end It will fall at the same falling speed.

Therefore, according to the present invention, it is possible to (a) prevent the wire rod coil (wire ring) from getting stuck during transportation; (b) prevent the formation of defective shapes due to coil removal; and c) control the temperature of the wire rod coil over the entire wire rod. This has extremely beneficial effects in the direct heat treatment of hot rolled wire rods, such as making it almost uniform.

Therefore, the conveyor 4 on the lower side of the stepped portion 8 in the present invention
There is no particular restriction on providing a coil thrust prevention device near the coil falling position in b.

The present applicant has already applied for the provision of this coil thrust prevention device (the coil thrust is also referred to as a prevention device), and the present invention will be even more beneficial if this device is added to the present invention.

Furthermore, if the level difference conveyor 4 can be raised and lowered freely as in the case of a tilting cheeple system, the level difference (the upper side conveyor 4
The transfer part a is 2
00 to 400 mm) can be appropriately selected depending on the quality target of the wire to be cooled.

However, in this invention, is it possible to raise and lower the step conveyor 4?
There is no particular restriction on whether it is a fixed type, and the selection is at the discretion of those skilled in the art.

A specific example of the present invention will be described below based on the drawings.

FIG. 3 is a perspective explanatory view showing the step portion of the step conveyor 40 of FIG. 1 according to the present invention, and FIG. 4 is a plan view of FIG. 3.

As shown in the figure, only the topmost transfer roller 9 of the upper conveyor 4a constituting the step portion 8 of the step conveyor 4 is driven in a cantilever manner, and the rollers 9 and 9 are divided, and the opposing roller surfaces are shaped approximately conically. is forming.

These opposing conical combination surfaces form a notch guide portion 10 corresponding to the curvature of the wire ring 30 shown by the two-dot chain line in the figure.

Therefore, as shown in plan view in FIG. 4, the final end X of the wire ring 3 falls from the notch guide part 10 while passing through, and is unraveled from the following group of wire rings to the lower conveyor 4b forming the stepped portion 8. To go.

Since the transition part of the upper conveyor 4a has a substantially flat roller arrangement, the leading edge Y and the rearmost edge X of the wire ring 3 fall at approximately the same falling speed and fall position on the lower conveyor 4b. fall to.

In other words, when the wire ring 3 falls like this, when the leading edge Y of the wire ring 3 protrudes forward from the stepped portion 8 and the rearmost end X reaches the notch guide portion 10 as shown in FIG. Since X cannot be supported (becomes free) by the opposing substantially conical portions of rollers 9 and 9, the leading edge Y
and the rearmost end X fall to the lower conveyor 4b at approximately the same falling speed.

Therefore, there is almost no chance that the phenomenon of the wire ring 3 falling while being uncoiled as shown in the enlarged view in FIG. 2 will occur.

Therefore, the shape of the wire ring 3 falling through the stepped portion 8 can be maintained in the most preferable shape without impairing quality, and the temperature can be made almost uniform over the entire wire ring, so that variations can be avoided. Extremely small metallographic structure and mechanical properties can be obtained.

In this case, if the level difference 8 between the upper conveyor 4a and the lower conveyor 4b of the present invention is, for example, 200 to 400 mm, the wire ring 3 forming the loose coiled wire can be peeled off. .

Note that the dimensions of the substantially conical portions of the rollers 9, 9, the notch guide portion 10, etc. are determined to better suit the diameter, curvature, etc. of the wire ring 3.

In this way, the present invention provides a cantilever drive type roller with a substantially conical portion that corresponds to the curvature of the wire ring at the top of the transfer tip of the upper conveyor of the step conveyor, and is provided with a cantilever drive type roller to match the curvature of the wire ring. Since the notch guide portion is configured accordingly, the wire ring passing through this stepped portion can fall at approximately the same speed at the leading end and the trailing end.

Therefore, at the step position (peeling position), the tip of the coil does not stick between the rollers of the lower conveyor, and is smoothly transferred onto the conveyor and stably conveyed.

Therefore, in the present invention, a) it is possible to prevent the wire coil (wire ring) from sticking, b) it is possible to prevent the formation of defective shapes due to the coil being removed, and c) the temperature of the wire coil is almost uniform throughout the entire wire rod coil. 2) Since online heat treatment is not interrupted, productivity can be improved, which has extremely practical effects.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a wire cooling line to which the present invention is applied, Fig. 2 is a side view showing the state of the coil thrust in the step conveyor of Fig. 1, and Figs. 3 and 4 are schematic diagrams showing an example of the present invention. FIG. 1... Laying head, 2... Roller conveyor, 3
... Wire ring, 4 ... Step conveyor, 5 ... Heat insulation cover, 6 ... Rapid cooling conveyor, 7 ... Concentration device, 8
...Step location, 9... Cutting edge roller, 10... Notch guide portion.

Claims (1)

[Scope of Claim for Utility Model Registration] A step conveyor that carries hot-rolled wire rods in a group of overlapping rings staggered by a certain distance is loaded and transferred, and the transfer point of the conveyor 4a on the upper side of the step point 8 is at the leading edge. ,
A hot-rolled wire rod characterized in that a cantilever drive roller 9.9 is provided with substantially conical portions corresponding to the curvature of the wire rod ring 30 facing each other to intercept the wire ring guide notch 10. Step conveyor for direct heat treatment.