JPH06170441A - Method and device for mechanical descaling - Google Patents

Abstract

PURPOSE:To enable efficient mechanical descaling by passing a traveling metallic wire through a twist generating part which is forcibly turned around the axial center of the metallic wire and descaling with the difference of toughness of the metallic wire and a scale. CONSTITUTION:Rollers 17A and 17B are constituted to connect through a connecting bar 25 by which the rollers are freely revolved and rotatable anticlockwise by 180 deg. with the connecting bar 25. In this constitution, a twist generating state is very easily obtained since the wire 5 is very easily inserted through between the rollers 17A and 17B in a stand-by state and the bar 25 is rotated by 90 deg., and then, succesively by 90 deg. anticlockwise to be displaced. The scale stuck on the surface of the wire 5 falls since the scale is given no toughness and cannot be twisted and an adhesivity is generated between the wire and the scale. Twist propagation preventing members are provided on both of upstream and down-stream sides of the twist generating part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for mechanically removing the scale on the surface of a metal wire, and more particularly to a completely new descaling technique in which the metal wire is twisted to remove the scale. is there.

[0002]

2. Description of the Related Art A metal wire rod is exposed to a high-temperature oxidizing atmosphere during its manufacturing process, so that scale is attached to its surface. Since this scale causes, for example, die seizure during wire drawing in the next step, it must be removed as completely as possible.

The scale removing technique is a chemical method (pickling method).
And mechanical method (mechanical descaling method), but the former is not so favored in recent years due to the problem of waste liquid treatment. On the other hand, the latter method includes (1) a reverse bending method in which a running wire rod is passed through several rollers to repeatedly bend back, and (2) a shot blasting method in which small particles are sprayed onto the wire rod. It is effective.

[0004]

However, each of the above methods has its own problems. For example, in the reverse bending method, it is not possible to perform the repeated bending back of the wire material uniformly in the entire circumferential direction, as will be described below, and some scale unremoved portions occur.

FIG. 9 is an explanatory view showing the overall concept of the reverse bending method, in which the wire 5 travels in the box 6 from left to right. The inside of the box 6 is divided into a reverse bending portion 8 and a brushing portion 9 by a partition plate 7, and the wire rods 5 are rollers 1, 2, 3 and 4 (referred to as first roller, second roller, third roller and fourth roller, respectively). (4) is bent in different directions in the process of passing through and the scale is designed to be peeled off by utilizing the toughness difference between the wire 5 and the scale. Then, in the brushing section 9, the residual scale is removed,
The wire rod 5 exiting the box 6 is drawn by, for example, a die (not shown).

FIG. 10 shows the wire 5 and the rollers 1, 2, 3, 4
10A to 10F are explanatory views showing the contact situation of FIG. 10, the characters "from the front" and "from the top" in FIGS. 10A to 10F correspond to the states viewed from the "front" and "from the top" shown in FIG. It is a thing. The view of this figure will be described by A when the first roller is seen "from the front".
It is pressed against the lower peripheral surface 1a. The white triangle mark and the black triangle mark, and the white circle mark and the black circle mark are given for the convenience of understanding of the following description. In A, only the black circle mark contacts the outer peripheral surface 1a of the first roller 1. , The triangle marks are not in contact with the peripheral surface of the roller.

Next, in B, since the axis of the second roller 2 is arranged parallel to the axis of the first roller 1, the wire 5 is bent in the opposite direction. The white circle mark is abutted on the outer peripheral surface 2a of the second roller 2. C is a view of the second roller 2 seen from above (hence, the white circle mark is in contact with the roller outer peripheral surface 2a).
3A to 3D show a transition process from the second roller 2 to the third roller 3. The axes of the second roller 2 and the third roller 3 are arranged orthogonally to each other, but the intention is to just keep the parallel arrangement such as between the first roller 1 and the second roller 2 to make contact points with the rollers. The black circle mark and the white circle mark are repeated and the bending is always repeated in the opposite direction by 180 degrees, and the contact point cannot be changed to the black triangle mark and the white triangle mark, and therefore the scale removal direction is specified. This is because it was feared that the unremoved part would be left behind. However, in actual operation, the wire rod 5 is already given a bending behavior in a specific direction, and exhibits a large resistance to bending in other directions. Being restrained by and easily receiving a 90 degree twist. Therefore, the wire 5 is -9 for bending 180 degrees.
Due to the 0 degree twist effect, it is apparently 90 ° clockwise in the figure.
The third roller 3 reaches the third roller 3 (reverse sideways in the figure) after being rotated. Therefore, in D, the black circle mark on the outer peripheral surface of the wire 5 comes into close contact with the roller outer peripheral surface 3a. Therefore, the attempt to change the contact point with the outer peripheral surface of the roller is often not achieved.

Further, in E, the fourth roller 4 is the third roller 3
However, for the same reason as above, the wire 5 is bent by 180 degrees and twisted by +90 degrees, and is apparently rotated 90 degrees counterclockwise in the figure ( It reaches the fourth roller 4 in the vertical direction in the figure). Therefore, in E and F (E is a view seen from above and F is seen from the front), the white circle mark comes into contact with the roller peripheral surface 4a, and the contact point of the wire is not changed to the black triangle mark or the white triangle mark. Therefore, the wire 5 is always repeatedly bent in the same plane in the process of being transferred from the first roller 1 to the fourth roller 4, and therefore the scale removal is limited to a specific portion. It will be accompanied by defects.

The present invention has been made in view of the above circumstances, and an object of the present invention is to establish a mechanical descaling technique based on a completely new viewpoint that is free from the drawbacks of the reverse bending method. It is a thing.

[0010]

The completely new mechanical descaling technique according to the present invention includes a method invention part and a device invention part, and the former includes the metal wire rod while running the metal wire rod. The gist of the present invention is to remove the scale by passing through a twist generating portion that is forcedly rotated around the center and by the toughness difference between the metal wire and the scale. On the other hand, the device invention includes two inventions, and the first device invention is such that the displacement running portion for running the metal wire curved along the peripheral surface of the roller is rotated around the axis of the metal wire in the transfer direction. A member and a twist propagation preventing member that sandwiches the twist generating member and restrains a metal wire rod from a part in the circumferential direction under running conditions on both the upstream side and the downstream side thereof to prevent the twist propagation. On the other hand, in the second invention, two twist generating members in the first device invention are provided along the traveling direction of the metal wire rod, and the upstream side with respect to the turning direction and the turning speed of the downstream twist generating member. The side twist generating member is turned in the opposite direction and at a lower speed to be a twist propagation preventing function member, and the twist propagation preventing member of the first device invention is provided further downstream of the downstream twist generating member. It is intended to.

[0011]

The present invention has the gist of forcibly turning the metal wire around its axis while running the metal wire, and the metal wire is twisted due to its sufficient toughness. Since the scale attached to the surface has almost no toughness, it cannot follow the above-mentioned twist, and as a result, a peeling force acts between them to cause the scale to fall off. Although there is no restriction on the mechanical structure for the occurrence of twist, normally, the running wire is twisted by causing it to rotate around the axis of the wire with the running shaft trace slightly displaced. The twist propagation preventing members are provided on the upstream side and the downstream side of the twist occurrence portion. Although the mechanism and structure of such a twist generating member and the propagation preventing member are not particularly limited, a typical example thereof will be described with reference to Examples described later.

[0012]

1 to 3 are explanatory views showing an example of a twist generating member, all of which include a roller 1 for displacing a wire rod in a casing 14.
5, 16A, 16B ..., 17A, 17B are stored,
On the other hand, center guide rollers 18 are provided at the inlet end and the outlet end of the casing 14 to guide the wire 5 so as not to be displaced from the axial center of the casing 14. Since the gear 19 provided at one end of the casing 14 is connected to the motor 21 via the transmission gear 20, the casing 1
4 is swung as shown by an arrow A in each example of FIGS.
Accordingly, the wire rod displacing rollers 15, ... Of each figure are also swung in the direction of arrow A accordingly. The wire rod displacing rollers 15, ... Shown in the respective drawings are all arranged with the axis of the casing 14 as line (or point) symmetry, but the line (or point) symmetry with the axis removed Or non-line (or dot)
The symmetrical arrangement is also an embodiment of the present invention.

With respect to the arrangement of the rollers 17A and 17B shown in FIG. 3, the connecting bar 25 that rotatably connects the rollers 17A and 17B to each other is provided at (b-1) to (b- in FIG. 3).
It is recommended to have a structure that can rotate counterclockwise by 180 degrees according to the circumstances shown in 3). In this way, (b-
It is extremely easy to pass the wire 5 between the rollers 17A and 17B in this state with 1) as the standby arrangement, and then rotate 90 degrees counterclockwise to (b-2), and then continue counterclockwise. It is also very easy to obtain the state of (a) by rotating it by 90 degrees and displacing it to the state of (b-3). 4 and 5 show an example of a mechanism for preventing twist propagation, and in FIG. 4, a front view of the grooved roller 22 (a).
And, as shown in the side view (b), by winding the wire 5 around the roller 22 at least once, the wire is restrained from a part in the circumferential direction without obstructing the running of the wire itself and the twist propagation is prevented. To achieve. In FIG. 5, a plurality of pressure contact rollers 23 are eccentrically provided between the pinch rollers 24, 24 to provide the same restraint as described above, and the twist propagation is prevented by these actions.

FIGS. 6 and 7 are explanatory views showing the concept of the present invention constructed by combining these twist generating members and twist propagation preventing members, and FIG. 16 is an example of the case of the first invention device, FIG. Are examples of the case of the second invention device. In FIGS. 6 and 7, 10 is a tensioning straightening box, 11A (11B) is a twist propagation preventing member, and 12 (1
2A and 12B) are twist generating members, and 13 is a die box.

First, referring to FIG. 6, the twisted wire member 5 is twisted by the twist generating member 12, but since the twist propagation preventing members 11A and 11B are provided on the upstream side and the downstream side thereof, respectively. , With the twist fixed, leave the box 6 and press the die box 13
The wire is drawn in.

Next, FIG. 7 shows two twist generating members 12A,
12B is used, and the upstream twist generating member 12A functions as a twist propagation preventing member by turning the downstream twist generating member 12B in the opposite direction and at a low speed, while further reducing the twist generating member 12B on the downstream side. A twist propagation preventing member 11B similar to that shown in FIG. 6 is disposed downstream.

FIG. 8 is a graph showing the results when mechanical descaling is performed by the twist method of the method of the present invention. The horizontal axis shows the number of twist rotations per 300 mm, and the vertical axis shows the residual scale rate (%). The following steel wire rods with a diameter of 5.5 mm are targeted, and rollers with a diameter of 85 mm (first to fourth in FIG. 1) are used.
Descaling was performed using a roller. The additional distortion at that time is calculated by the following equation. Additional distortion = [5.5 / (85 + 5.5)] × 100 = 6.
1% Chemical composition of steel wire: C: 0.92% Si: 0.25% Mn: 0.48
% Cr: 0.02% Ni: 0.02% P: 0.008
% S: 0.009% Pretreatment: Direct rolling patenting Scale deposit: 0.42 wt%

As shown in FIG. 8, the torsional rotation speed is 1.0
It has been confirmed that when the number of turns / 300 mm is exceeded, the residual scale ratio sharply decreases, and the risk of causing a seizure problem with the die during the wire drawing in the subsequent step becomes extremely small. The reduction of the residual scale ratio is saturated at the torsional rotation speed of 1.0 rotation / 300 mm, and it is not necessary to further increase the torsional rotation speed. Rather, the twisting speed is 2.0 times / 3
If it exceeds 100 mm, the amount of strain due to twisting increases and waviness may occur in the wire material, which may adversely affect the wire drawing in the next step. However, the preferred range of the twisting rotational speed differs depending on the strength and the wire diameter of the wire rod, so that it is not uniformly set in the present invention.

Next, the results of mechanical descaling when the number of twist rotations was set to 1.0 times / 300 mm and the results of further wire drawing were summarized, and for comparison, the same wire rod was used as a mechanical method by the conventional bending method. As a result of comparison with the results of descaling and wire drawing, the results are shown in Table 1. In each case, after mechanical descaling, a calcium stearate-based lubricant was used, and the wire was drawn from a diameter of 5.5 mm to 3.0 mm with five dies.

[0020]

[Table 1]

As shown in Table 1, in the conventional bending method, a scale that could not avoid seizure remained, but in the twisting method of the present invention, seizure occurs in all dies even if the wire drawing speed is increased. There wasn't.

[0022]

Since the present invention is constructed as described above, it has high strength metal wire, especially medium / high carbon steel wire, Cr, Ni,
It has become possible to perform efficient mechanical descaling even for a metal wire rod that is difficult to mechanically descale, such as an alloy steel wire rod containing an alloy component such as Si or Co.

[Brief description of drawings]

FIG. 1 is a conceptual explanatory view showing an example of a twist generating member.

FIG. 2 is a conceptual explanatory view showing an example of a twist generating member.

FIG. 3 is a conceptual explanatory view showing an example of a twist generating member.

FIG. 4 is a conceptual explanatory view showing an example of a twist propagation preventing member.

FIG. 5 is a conceptual explanatory view showing an example of a twist propagation preventing member.

FIG. 6 is an explanatory diagram showing the overall concept of the device of the present invention.

FIG. 7 is an explanatory diagram showing the overall concept of the device of the present invention.

FIG. 8 is a graph showing the effect when mechanical descaling is performed according to the present invention.

FIG. 9 is an explanatory diagram showing an overall concept of a conventional device.

FIG. 10 is an explanatory diagram showing a contact state between each bending roller and a wire rod in a conventional device.

[Explanation of symbols]

 1 Bending 1st Roller 2 Bending 2nd Roller 3 Bending 3rd Roller 4 Bending 4th Roller 5 Wire Rod 11 Twist Propagation Prevention Member 12 Twist Generation Member

Front Page Continuation (72) Inventor Mamoru Murahashi 2 Nadahama Higashi-cho, Nada-ku, Kobe-shi, Hyogo Stock Company Kobe Steel Works Kobe Steel Works

Claims (3)

[Claims] 1. When removing the scale on the surface of a metal wire through a mechanical descaling step, the metal wire is made to pass through a twist generating portion forcibly turning the metal wire around its axis while running the metal wire. A mechanical descaling method characterized by removing the scale by the difference in toughness between the wire and the scale. 2. A twist generating member configured to swivel a displacement running part for running the metal wire curved along the peripheral surface of the roller around an axis of a transport direction of the metal wire, and the twist generating member. A mechanical descaling device, characterized in that a twist propagation preventing member is provided on the upstream side and the downstream side to restrain the propagation of twist by restraining a metal wire rod from a part in the circumferential direction under running conditions. 3. The twist generating member according to claim 2 is provided in two along the traveling direction of the metal wire, and the upstream twist generating member is turned in the opposite direction to the turning direction and the turning speed of the downstream twist generating member. A mechanical descaling device, characterized in that a twist propagation preventing function member is provided for a slower speed rotation, and the twist propagation preventing member according to claim 2 is provided further downstream of the downstream side twist generating member.