JP2011020159A - Scraper device for squeeze roll in electric resistance welded tube production equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a scraper device which can actually effectively remove deposits such as sputters and slags deposited on top rolls in squeeze rolls. <P>SOLUTION: The scraper device for a squeeze roll functions to remove deposits 10 adhering to a portion in the proximity of a corner of the inner part of each of left and right top rolls 9 of the squeeze roll, when the squeeze roll in a high-frequency welding part in an electric resistance welded tube production equipment is of a four-roll or five-roll type. A scraper 21 comprising a high heat-resistant and abrasion-resistant resin material is provided so as to abut against a portion in the proximity of the inner corner part of the upper part in a high frequency heating part side (right side in Fig.4) of the left and right top rolls 9. Since the scraper in a position abutted against the top rolls is located in the upper part of the high frequency heating part side of the top rolls, sputters and slags become cooled and embrittle to a suitable extent until the top rolls are rotated to allow the deposits to reach the scraper, whereby the deposits can be effectively scraped away by the high heat-resistant and abrasion-resistant resin scraper. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a scraper device for a squeeze roll that removes deposits such as spatter adhering to a top roll of a squeeze roll when the squeeze roll of a high-frequency welded part in an electric sewing tube manufacturing facility is a 4-roll system or a 5-roll system. About.

  In the electric sewing tube manufacturing facility, as schematically shown in FIG. 13, the metal plate 1 ′ continuously fed from the uncoiler 2 by the pinch roll 3 is bent in an arc shape by a plurality of breakdown rolls 4. Subsequently, both ends of the metal plate are formed into a tubular cross section with the fin pass roll 5 separated from each other, and then the edge is heated by the high frequency welding machine 6 of the welded portion, and a circumferential compression force is applied by the squeeze roll 7 to the end. The edges are butt welded to form the tube 1.

FIG. 14 is a plan view showing a simplified portion of the squeeze roll 7 which is a welded portion of the above-described electric welded tube manufacturing equipment.
As shown in the drawing, the squeeze roll 7 of the present invention is a four-roll system comprising a pair of left and right side rolls 8 as viewed from the material feed direction and a pair of top rolls 9 on the left and right, or a receiving roll ( This is a five-roll squeeze roll with a cover that cannot be seen in FIG.
The configuration shown in FIG. 14 is a general configuration as a 4-roll (or 5-roll) type squeeze roll. The configuration of the squeeze roll 7 viewed from the front is the same as that of FIG. 3 in the case of the 5-roll system (except for the scraper device 20 of the present invention).
The high-frequency welder in the illustrated example is a high-frequency resistance welder, and reference numeral 6 indicates a contact tip of the high-frequency resistance welder.
In FIG. 14, reference numerals 1 denote both the front and rear tubular bodies (that is, both the tubular metal plate 1 ′ in which the edges are not closed and the pipe in which the edges are closed together). Show.

When the contact tips 6 of the high-frequency resistance welder are brought into contact with the V-shaped ends of the tubular body 1 that are not yet closed and the high-frequency current is passed through the contact tips 6, the both-end edges 1 a and 1 a are still in the tubular body 1. However, due to the skin effect and the proximity effect, the current concentrates on both end edges 1a and 1a converging facing each other in a V shape, and both end edges are heated by Joule heat and pass through the squeeze roll 7. Both end edges are butted and pressed (butt welded) by the compressive force in the circumferential direction. The pair of upper left and right top rolls 9 are in contact with the tubular body 1 at positions close to both end edges.
At this time, in the vicinity of the welding point, sparks are discharged, the molten metal is scattered and spatter solidified in a granular manner is continuously generated and deposited on the top roll 9. On the weld bead surface, slag, which is an oxide floating on the surface of the molten metal, is deposited and adheres to the top roll 9.
These deposits such as spatter or slag are close to the end edge 1a of the tubular body 1 with the open end, as shown in FIG. It accumulates on the roll outer peripheral surface 9b and the roll side surface 9c in the vicinity including the corner portion 9a of the top roll 9. Since spatter and slag deposited on the top roll cannot be distinguished by mixing, both spatter and slag are referred to as deposits. The deposit is indicated by 10.

If the pipe making operation is continued with these deposits attached to the top roll 9, the deposits 10 become thick as shown in FIG. Therefore, there is a problem that the yield decreases.
For this reason, although the deposit adhering to the top roll is removed before it becomes thick, it was necessary to stop the line and scrape off with a grindstone or a sander in order to remove this deposit.

As a method for removing deposits such as spatter and slag adhering to a squeeze roll of a high-frequency welded part of an electric-welded pipe manufacturing facility, there are Patent Literature 1 and Patent Literature 2 although preconditions are different from those of the present invention.
Although not shown, Patent Document 1 is a two-roll squeeze roll (see paragraph number [0002] of Patent Document 1, FIGS. 2 and 3) composed of a pair of left and right side rolls, and mainly. In the case of manufacturing a pipe such as copper or brass, the squeeze roll 37 is brought into contact with the side surface (concave surface 28 or upper collar portion 30) of the rotating squeeze roll (side roll) 8 so that the squeeze roll The spatter adhering to the side surface or the like is wiped off. As the material of the wiping member 37, a heat-resistant, wear-resistant, and highly flexible fiber material or the like (Nell or the like) is assumed (note that the code is a code in Patent Document 1).

Patent Document 2 is also a two-roll type squeeze roll (see FIGS. 1 and 2) 4 composed of a pair of left and right side rolls, but is opposite to the high-frequency heating unit 2 of the squeeze roll (side roll) 4. The scraper 9 is applied to the flange portion (cylindrical portion 7 adjacent to the contact portion (engagement portion 6) with the electric sewing tube 5) to remove the slag accumulated on the flange portion 7 ( In addition, a code | symbol is the code | symbol in patent document 2.).
In this cited document 2, the slug accumulated on the flange portion 7 of the side roll 4 prevents the gap between the left and right side rolls 4 from widening, thereby reducing the restraining force of the roll and reducing the accuracy of the product.

JP2003-1325A JP 9-220616 A

As described above, if the pipe making operation is continued while deposits such as spatter and slag are attached to the top roll 9, the product will be dented and scratched, so the deposit attached to the top roll will not be thick. However, in order to remove this deposit, it is necessary to stop the line and scrape off with a grindstone or a sander, which has a problem of significantly reducing productivity.
Note that the squeeze rolls of Patent Document 1 and Patent Document 2 are a two-roll system consisting of a pair of left and right side rolls, and there is no upper top roll. The method for removing objects cannot be adopted. In addition, the two-roll method is generally employed in the manufacture of small-diameter pipes, and the situation is different in that the four-roll or five-roll method targeted by the present invention is applied to large-diameter pipes.

  The present invention has been made in view of the above circumstances, and is a scraper device for a squeeze roll capable of effectively effectively removing deposits such as spatters attached to a squeeze roll of a high-frequency welded part in an electric resistance welded pipe manufacturing facility. The purpose is to provide.

The invention of claim 1 that solves the above-mentioned problem is that the squeeze roll of the high-frequency welded part in the electric welded tube manufacturing facility is a four-roll system comprising a pair of left and right side rolls and two left and right top rolls, or a receiving roll. A squeeze roll scraper device that removes deposits such as spatter and slag adhering to the vicinity of the inner corners of the left and right top rolls, respectively,
A scraper made of a resin material having high heat resistance and wear resistance is provided so as to hit the vicinity of the upper inner corner of the left and right top rolls on the high frequency heating section side.

  According to a second aspect of the present invention, in the scraper device of the first aspect, the scraper is made of MC nylon.

  According to a third aspect of the present invention, in the scraper device according to the first or second aspect, the contact position where the scraper hits the top roll is within a range of 220 to 240 ° from the welding point to the top roll rotation direction.

  Claim 4 is the scraper device according to any one of claims 1 to 3, wherein the scraper has a plate shape and is a tilt angle of the scraper with respect to a tangential direction of the top roll as viewed from the longitudinal direction of the top roll axis. The angle α is set to 30 ± 10 °.

  Claim 5 is the scraper device according to any one of claims 1 to 4, wherein the scraper has a plate shape, and a twist angle β that is an inclination angle of the scraper with respect to the roll width direction viewed from the tangential direction of the top roll. Is in the range of 0 to 5 °.

  A sixth aspect of the present invention provides the scraper device according to any one of the first to fifth aspects, wherein the scraper has a plate shape, and the twist of the scraper is an inclination angle with respect to the roll width direction as viewed from the outer side in the top roll radial direction. The angle γ is in the range of 0 to 5 °.

  Claim 7 is the scraper device according to any one of claims 1 to 6, wherein the scraper forms a plate shape, and the shape of the portion that hits the top roll is defined by the roll side surface and the roll circumference that sandwich the corner portion of the top roll. It is characterized by having an L shape so as to come into contact with both surfaces.

  Claim 8 is the scraper device according to any one of claims 1 to 7, wherein the squeeze roll holder is provided with an elongated hole in front of a downward U-shaped holder yoke that pivotally supports the squeeze roll so as to be directly rotatable. And a scraper attached to the bracket. The scraper is attached to the bracket.

  According to a ninth aspect of the present invention, in the scraper device according to any one of the first to eighth aspects, the scraper is attached to the bracket with a taper block for adjusting the rake angle α of the scraper interposed therebetween.

  A tenth aspect of the present invention provides the scraper device according to any one of the first to ninth aspects, wherein the scraper is slidably attached to the bracket via an elastic member that elastically biases the scraper toward the outer peripheral surface of the squeeze roll. It is characterized by that.

With the squeeze roll scraper device of the present invention, it has become possible to effectively remove deposits such as spatter and slag adhering to the vicinity of the corner inside the top roll of the squeeze roll.
In particular, the contact position of the scraper with respect to the top roll is the upper part of the top roll on the high-frequency heating part side, that is, in the range of 180 to 270 ° from the welding point to the top roll rotation direction. These deposits are appropriately cooled and embrittled before reaching the scraper, and are easily scraped off by the scraper. For this reason, even if the material of the scraper is a resin having a hardness lower than that of a metal or ceramic having a high hardness, for example, the deposit can be effectively removed if it is a wear-resistant resin such as MC nylon.
Moreover, if it is the range of 180-270 degrees from a welding point, since the temperature of a top roll outer peripheral surface and a deposit can fully be cooled by fully applying a cooling water to a top roll, and in a scraper part, However, if the cooling water is sufficiently applied, heat transfer to the scraper can be reduced as much as possible. Therefore, if a heat resistant resin such as MC nylon is used as the material of the scraper, no problem occurs.
Further, since the scraper is a resin, the roll surface is not damaged.
In addition, when a high frequency induction welder is used as the high frequency welder, if the scraper is made of a magnetic material such as iron, an induction current is generated in the scraper itself and the scraper is heated to a high temperature. Such a problem does not occur.

  If the material of the scraper is MC nylon as in claim 2, the heat resistant temperature (continuous use temperature) is 110 ° C. or higher and the wear resistance is very good, so that the durability is excellent and the material of the scraper of the present invention. Is particularly suitable.

  As in claim 3, when the contact position of the scraper with respect to the top roll is in the range of 220 to 240 ° in the top roll rotation direction from the welding point, it is also effective in that the outer peripheral surface of the top roll and the deposit are appropriately cooled. However, it is also effective in discharging the scraped deposit without retaining it).

  As described in claim 4, the rake angle α of 30 ± 10 ° of the scraper is effective for appropriately scraping off the deposit.

  Further, as in claim 5, the scraper has a twist angle β (see FIG. 5C) which is an inclination angle with respect to the roll width direction as viewed from the tangential direction of the top roll, that is, the scraper is arranged in the roll width direction. In contrast, by inclining outward in the roll radial direction, it is possible to appropriately correspond to the concave outer peripheral surface of the top roll. In addition, when the difference between the thickness of the deposit on the outer surface of the top roll and the thickness on the side surface is large, for example, the thickness of the top roll is inclined to the larger side. It can also be adjusted to correspond.

  Further, as in claim 6, when the scraper has a twist angle γ that is an inclination angle with respect to the roll width direction as viewed from the outer side in the top roll radial direction, that is, the scraper is arranged in the roll circumferential direction with respect to the roll width direction. By tilting, the contact length with the roll surface of the scraper becomes longer and the contact area becomes wider, so that a shear angle effect that reduces the scraping force (resistance force) per unit area acting on the scraper can be obtained, and the deposit is scraped off. It becomes easy. The twist angle γ is suitably 0 to 5 °.

  According to the seventh aspect, since the portion of the scraper that hits the top roll is L-shaped, deposits attached to the outer peripheral surface and the side surface of the roll near the corner of the top roll can be effectively scraped off.

  When the scraper is attached to the bracket attached to the holder yoke so as to be movable and adjustable, the scraper can easily correspond to various squeeze rolls having different roll diameters.

  When the scraper is attached to the bracket with the taper block interposed as in claim 9, the rake angle of the scraper can be easily changed by preparing plural types of taper blocks having different angles of the scraper mounting surface. Can do.

  If the scraper is configured to be pressed against the squeeze roll by the force of the elastic member, the pressing force against the squeeze roll can be automatically adjusted.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 schematically shows an embodiment of a scraper device for a squeeze roll according to the present invention, and is a plan view schematically showing the vicinity of a squeeze roll device for a welded part in an electric resistance welded pipe manufacturing facility. It is the perspective view which expanded and showed the principal part in FIG. It is a front view of the squeeze roll apparatus which attached the scraper apparatus of one Example of this invention. (A) is the side view seen from the roll axis longitudinal direction of the top roll part which attached the scraper apparatus on the left side in FIG. 3, (B) is the right side view of (A). It is a figure explaining the position and attitude | position of a top roll, (a) is a figure explaining the rake angle (alpha) which is an inclination angle with respect to the top roll tangent direction seen from the top roll axis | shaft longitudinal direction, (b) is a top roll tangent direction FIG. 6 is a diagram for explaining a twist angle γ that is an inclination angle with respect to the roll width direction as viewed from (a view as viewed from the A direction in (A)); It is a figure (figure seen from the B direction of (A)) explaining the twist angle (beta). It is the figure seen from the front in case a scraper has twist (beta) of FIG. The shape of the scraper of the said Example is shown, (A) is a front view, (B) is a left view of (A). The shape of the scraper of another Example is shown, (A) is a front view, (B) is a left side view of (A). The Example which provided the elastic member which presses a scraper to a top roll is shown, (A) is a side view, (B) is a front view. The scraper is attached to the bracket via a taper block. (A) shows the scraper plate surface forming a rake angle α. (B) and (c) show that the lower end surface of the scraper is raked. In this case, the angle α is formed. It is a figure which shows the Example which attached the scraper which made the front-end | tip part which hits a top roll into the taper surface to the bracket via the taper block. The Example which made the lower part of a scraper the sharp acute angle wide taper surface is shown, (A) is a figure which shows the case where it attaches directly to a bracket, (B) shows the case where it attaches to a bracket via a taper block. It is the side view which showed typically the structure of the principal part of general electric sewing pipe manufacturing equipment. It is the top view which demonstrated the conventional problem and simplified and showed the vicinity of the squeeze roll apparatus of the welding part in an ERW pipe manufacturing equipment. FIG. 10 is a partial cross-sectional view of a top roll for explaining a situation where deposits such as spatter and slag adhere to the top roll.

  Examples of the squeeze roll scraper device of the present invention will be described below with reference to FIGS.

In the electric sewing tube manufacturing facility, as schematically shown in FIG. 13, the metal plate 1 ′ continuously fed from the uncoiler 2 by the pinch roll 3 is curved in an arc shape by the plurality of breakdown rolls 4. Subsequently, both ends of the metal plate are formed into a tubular cross section with the fin pass roll 5 separated from each other, and then the edge is heated by the high frequency welding machine 6 of the welded portion, and a circumferential compression force is applied by the squeeze roll 7 to the end. The edges are butt welded to form the tube 1.
Although not shown in the figure, the weld bead is then scraped off with a bead trimmer, cooled with cooling water in a cooling zone, and shaped with a multi-stage sizing roll (with a squeeze to a desired outer diameter of a round tube or a desired size) It is shaped into a square tube size, cut with a cutting machine, and sent to a stock yard. In addition, although a looper installation is normally provided between the pinch roll 3 and the breakdown roll 4, illustration was abbreviate | omitted.
In the examples, an electric resistance welded pipe manufacturing facility for manufacturing a structural square steel pipe is assumed. However, as a size, a plate thickness of 4.5 to 16 mm, etc., and 125 to 500 mmφ or the like at a stage where a round steel pipe is formed with a squeeze roll. A large steel pipe is assumed. Of course, the amount of spatter and slag attached to the welded part in the ERW pipe manufacturing facility for manufacturing large-size steel pipes is significantly larger than that for small-size steel pipes.

FIG. 1 is a plan view schematically showing a portion of a squeeze roll 7 which is a welded portion of the above-described electric welded tube manufacturing equipment, and FIG. 2 is a perspective view of the main part of FIG.
The high-frequency welder in the illustrated example is a high-frequency resistance welder, and reference numeral 6 indicates a contact tip of the high-frequency resistance welder.
In FIG. 1, reference numerals 1 denote both front and rear tubular bodies (both a tubular metal plate whose ends are not closed or a tube whose ends are closed together).

As shown in FIG. 3, the squeeze roll 7 targeted in this embodiment is further received by a four-roll squeeze roll comprising a pair of left and right side rolls 8 and a pair of upper left and right top rolls 9. This is a 5-roll squeeze roll provided with a roll 11. The rotational axis of the side roll 8 is indicated by 8a.
As shown in the figure, the left and right top rolls 8 are each inclined so as to be directed substantially toward the center of the tubular body 1, and between the upper portions of the left and right side rolls 8, the outer peripheral surface of the tubular body 1 at a position close to the edge 1 a. Press.
The top roll 9 is attached to the face plate 13. A pair of left and right diagonally downward U-shaped frame portions 14 are fixed to the face plate 13, and a holder yoke 16 is connected to the lower end of a reduction screw 15 provided on the frame portion 14, and the top roll 9 rotates on the holder yoke 16. It is pivotally supported. The rotational axis of the top roll 9 is shown by 9d (FIGS. 1 and 2).
In addition, although an Example is a 5-roll system, naturally it is applicable similarly even if it is a 4-roll system without the receiving roll 11. FIG.

As shown in FIG. 4, a scraper device 20 is attached to the front surface of the holder yoke 16 (the surface on the right side in FIG. 4A: the surface on the high-frequency coil 6 side).
The scraper device 20 includes a scraper 21 made of plate-like MC nylon (registered trademark), and a bracket 22 for attaching the scraper 21 to the holder yoke 16. The MC nylon is selected from the various grades of high heat resistance and wear resistance. For example, MC901 / MC900NC can be used, or a grade having a higher heat resistance temperature is used. Also good.
The bracket 22 has a vertically long rectangular plate shape and has a vertically long slot 22a. The bolt 23 is screwed into a screw hole formed in the front surface of the holder yoke 16 through the slot 22a to fix the bracket 22 to the holder yoke 16. To do. A scraper 21 is fixed to the lower part of the front surface of the bracket 22 with bolts 24.
As shown in FIG. 7, the scraper 21 is a plate-like body having a protruding portion 21 a at the lower end of the rectangle, has two attachment holes in the upper portion, and has a L-shape with the lower end edge facing sideways. The scraper 21 is attached to the holder yoke 16 via the bracket 22 so that the L-shaped lower end edges 21b and 21c thereof face the roll outer peripheral surface 9b and the roll side surface 9c in the vicinity of the corner portion 9a of the top roll 9, respectively. It is done.
FIG. 8 shows another embodiment of the shape of the lower end portion of the scraper, in which the lower end surface of the scraper 21 is a tapered surface 21d.
Note that the L-shape of the lower edge of the scraper 21 is not necessarily a right angle, but may be an acute angle corresponding to the concave surface on the outer periphery of the roll. In some cases, an obtuse angle may be considered.

An appropriate position and posture of the scraper 21 with respect to the top roll 9 will be described with reference to FIG.
5A is a diagram for explaining the position of the scraper 21 in the top roll rotation direction and the rake angle α with respect to the top roll. FIG. 5B is a diagram seen from the A direction of FIG. (C) is the figure seen from the B direction of (a), and is a figure explaining the twist angle (beta).
The contact position P that contacts the top roll 9 of the scraper 21 is the upper part of the left and right top rolls on the high-frequency heating unit side (right side in FIG. 5, FIG. 4A, etc.) as seen from the material feeding direction. That is, the range is approximately 180 to 270 ° in the top roll rotation direction from the welding point M (θ in FIG. 5A is 180 to 270 °).
Also, the angle of the plate surface of the scraper 21 with respect to the roll tangent line a direction at the contact position P as viewed from the longitudinal direction of the top roll axis (the direction perpendicular to the paper surface in FIG. An angle of ± 10 ° is appropriate.
This rake angle α is determined by the contact position P of the scraper 21 that hits the top roll 9 and the inclination with respect to the vertical line. In the embodiment of FIG. 4, the scraper 21 is provided in a vertical posture, but it may be inclined with respect to the vertical line as shown in FIG.
The rake angle α of 30 ° ± 10 ° is effective for appropriately scraping off the deposit.

As shown in FIG. 5 (b), the scraper 21 is provided with a twist angle γ that is an inclination angle with respect to the roll width direction as viewed from the outer side in the top roll radial direction (viewed from the A direction in FIG. 5 (a)). Also good. In the embodiment shown in FIG. 4, the twist angle γ is 0, but the twist angle γ can be set in the range of 0 to 5 °.
When the twist angle γ is provided, that is, when the scraper 21 is inclined with respect to the roll width direction on the outer circumferential surface of the roll, the contact length with respect to the roll surface of the scraper becomes longer and the contact area becomes wider, so that per unit area acting on the scraper However, the twisting angle γ is suitably 0 to 5 °.
When scraping off deposits with the scraper 21, the scraped deposits need to be discharged smoothly without stagnation.
When the torsion angle γ is provided in the scraper 21, the scraper plate surface is inclined with respect to the roll circumferential direction and acts to scrape the deposits toward the sides, so that the scraped deposits are discharged smoothly. This is also effective.

As shown in FIG. 5 (c), the scraper 21 may be provided with a twist angle [beta] that is an inclination angle with respect to the roll width direction as seen from the tangential direction of the top roll (viewed from the B direction in FIG. 5 (a)). .
In the embodiment shown in FIG. 4, the twist angle β is 0 °, but it is preferable to set the twist angle β in the range of 0 to 5 °.
FIG. 6 is a front view (a view corresponding to FIG. 4 (B)) when the scraper 21 is provided with the twist angle β. In the front view of FIG. 6, the angle β ′ is slightly different from the twist angle β.
By setting an appropriate inclination angle β in the scraper 21, it is possible to appropriately correspond to the concave outer peripheral surface 9 b of the top roll 9, and it is possible to effectively scrape the deposit 10. Moreover, it can also adjust according to the adhesion thickness to the outer peripheral surface of the top roll 9, and the adhesion thickness to a side surface, and the scraping of the deposit 10 can also be performed effectively also in this point.

In addition, like a general electric welded tube manufacturing equipment, naturally, cooling water is applied to the top roll 9 that is heated to a high temperature by the heat of the welded portion, but the cooling water is also actively applied particularly to the scraper 21 portion. This prevents a problem with the heat resistance of the scraper 21 that is a resin.
In addition, an air ejection nozzle for discharging the deposit scraped by the scraper 21 may be provided toward the scraper 21.

When the contact tips 6 of the high-frequency resistance welder are brought into contact with the V-shaped ends of the tubular body 1 that are not yet closed and the high-frequency current is passed through the contact tips 6, the both-end edges 1 a and 1 a are still in the tubular body 1. However, due to the skin effect and the proximity effect, the current concentrates on both end edges 1a and 1a converging facing each other in a V shape, and both end edges are heated by Joule heat and pass through the squeeze roll 7. Both edge portions are butted and pressed (butt welded) by the compressive force in the circumferential direction. The pair of upper left and right top rolls 9 are in contact with the tubular body 1 at positions close to both end edges.
At this time, in the vicinity of the welding point, sparks are discharged, the molten metal is scattered and spatter solidified in a granular manner is continuously generated and deposited on the top roll 9. On the weld bead surface, slag, which is an oxide floating on the surface of the molten metal, is deposited and adheres to the top roll 9.
Since these sputter or slag deposits have corners 9a on the inner sides of the left and right top rolls 9 close to the end edge 1a of the tubular body 1 with the open end, as shown in FIG. It accumulates on the roll outer peripheral surface 9b and the roll side surface 9c that sandwich the corner 9a of the roll 9.
However, the deposited deposit 10 is deleted by the scraper 21 described above. That is, in FIG. 4 and FIG. 5, the deposit is appropriately cooled and embrittled before the spatter and slag reach the scraper 21 by rotating over 180 ° from the welding point M in the top roll rotation direction. It is easy to scrape off with the scraper 21. For this reason, even if the material of the scraper 21 is a resin having a hardness lower than that of a metal or ceramic having a high hardness, the deposits can actually be effectively removed.
Moreover, if it is the range of 180-270 degrees from a welding point, since the temperature of a top roll outer peripheral surface and a deposit can fully be cooled by fully applying a cooling water to a top roll, and in a scraper part, However, since the heat transfer to the scraper can be reduced as much as possible by applying sufficient cooling water, there is no problem for the scraper 21 made of MC nylon having a heat resistant temperature (continuous use temperature) of 110 ° C. or higher.
Further, the MC nylon scraper 21 does not damage the roll surface.
Further, if the scraper is made of a magnetic material such as iron, an induced current is generated in the scraper itself and the scraper is heated to a high temperature. However, since it is a resin, there is no such problem.
Further, as shown in FIG. 15, the deposit adheres to the corner portion 9 a of the top roll 9 and the roll outer peripheral surface 9 b and the roll side surface 9 c adjacent to the corner portion 9 a, but the portion of the scraper 21 that contacts the top roll 9 has an L shape. Therefore, it is possible to effectively scrape the deposit adhering to the outer peripheral surface 9b and the roll side surface 9c in the vicinity of the corner of the top roll 9 and adhering thereto.

  Since the bracket 22 to which the scraper 21 is attached is fixed to the holder yoke 16 with a bolt 24 in the elongated hole 22a, the vertical position of the scraper 21 can be adjusted by moving the bracket 22 up and down, It can correspond to various squeeze rolls having different roll diameters. That is, an appropriate pressing force can be easily set for various squeeze rolls having different roll diameters.

Deposits generated on the outer peripheral surface of the top roll and the welding point and adhered to the top roll are rapidly cooled by cooling water as the top roll rotates, and are sufficiently low in the range of 180 to 270 ° from the welding point to the top roll rotation direction. Become.
Since the heat resistance temperature of MC nylon is 110 ° C. or higher, there is no problem in heat resistance as long as it is within the range of 180 to 270 ° in the rotation direction of the top roll from the welding point, and the durability of MC nylon is as described above. Can be secured.
Moreover, if it is the position of this range, the sputter | spatter produced by a spark discharge will not reach a scraper and will not accumulate on scraper itself.
However, a range of θ = 220 to 240 ° is appropriate as a position for preventing the accumulated deposit from staying. Further, the range of θ = 220 to 240 ° is also appropriate in that the rake angle α can be easily set in the range of 30 ° ± 10 °.

FIG. 9 shows another embodiment of the scraper device. In the scraper device 30 of this embodiment, a scraper 21 is attached to a bracket 22 so as to be slidable up and down via a compression coil spring (elastic member) 31 that elastically biases the scraper 21 toward the outer peripheral surface of the squeeze roll. It is.
The scraper 21 is fixed to the lower end of a shaft 32 having a head portion 32a for retaining the shaft. The compression coil spring 32 is attached to the shaft 32, and a hole is formed in an overhang portion 34 fixed to the upper portion of the bracket 22. Or, with the head portion 32a above the groove, the upper overhanging portion 34 is engaged with the upper overhanging portion 34 so as to be vertically movable. The scraper 21 can slide up and down along a guide 22 a provided on the bracket 22.
Thereby, the scraper 21 is always pressed against the outer peripheral surface of the squeeze roll 9 by the reaction force of the compression coil spring 31.
Therefore, if the reaction force of the compression coil spring 31 is appropriately set, the pressing force of the scraper 21 against the squeeze roll 9 is automatically adjusted to an appropriate magnitude during the manufacture of the electric resistance welded tube.

FIGS. 10A, 10B and 10C show still another embodiment of the scraper device.
A scraper device 40 shown in FIG. 10A is configured by attaching a scraper 21 to a bracket 22 with a taper block 41 for adjusting a rake angle α of the scraper 21 interposed therebetween.
If a plurality of types of blocks 41 having different angles δ formed by the mounting surface 41a and the scraper mounting surface 41b on the bracket 22 are prepared, the rake angle α of the scraper 21 can be easily set by using the block 41 having an appropriate angle δ. Can be adjusted.

In the scraper devices 40 ′ and 40 ″ shown in FIGS. 10B and 10C, the scraper 21 is similarly attached to the bracket 22 with the taper block 41 interposed therebetween. The end face 21b forms a rake angle α, and Fig. 10 (c) shows a case where the plate surface of the scraper 21 is particularly horizontal.
In addition, illustration of the protrusion part 21a of the lower end of the scraper 21 was abbreviate | omitted in FIG. 10 (A), (B), and (C).

  FIG. 11 shows still another embodiment of the scraper device. The scraper device 50 of this embodiment uses a scraper 21 having a lower end surface of a tapered surface 21d, like the scraper 21 of FIG. The scraper 21 is attached to the bracket 22 via the taper block 41 as described above.

FIG. 12 shows still another embodiment of the scraper device.
12 (a) and 12 (b), the scraper devices 60 and 60 'each have a lower tapered portion 21e with a sharp sharp angle at the bottom of the scraper 21.
12A shows a case where the scraper 21 is directly attached to the bracket 22, and FIG. 12B shows a case where the scraper 21 is attached to the bracket 22 with the taper block 41 interposed.

In each of the embodiments described above, MC nylon is used as the scraper material, but the material is not necessarily limited to MC nylon. Any resin material having good heat resistance and wear resistance can be employed.
In the above description, the high-frequency welding machine is a high-frequency resistance welding machine.

1 tube (tubular body)
1 'metal plate 1a edge 6 high frequency heating part (contact tip of high frequency resistance welding machine)
7 Squeeze roll 8 Side roll 9 (of squeeze roll) Top roll 9a (of squeeze roll) Top roll 9a Corner portion 9b Roll outer peripheral surface 9c Roll side surface 10 Deposit (spatter and slag)
DESCRIPTION OF SYMBOLS 11 Receiving roll 13 Face plate 14 Frame part 15 Reduction screw 16 Holder yoke 20, 30, 40, 40 ', 40 ", 50, 60, 60' Scraper device 21 Scraper 21a Protrusion part 21b, 21c (L-shaped) lower end edge 21d Tapered surface 21e Tapered surface 22 Bracket 22a Guide portion 22a Slot 31 Compression coil spring (elastic member)
32 Shaft 32a Head 34 Overhang portion 41 Tapered block 41a Mounting surface 41b of (taper block) Scraper mounting surface α of taper block (rake angle) )
β Twist angle (tilt angle with respect to the roll width direction as seen from the tangential direction of the top roll)
γ Twist angle (tilt angle with respect to the roll width direction as seen from outside in the top roll radial direction)
δ Angle between the mounting surface on the bracket (of the taper block) and the scraper mounting surface

Claims (10)

When the squeeze roll of the high-frequency welded part in the ERW pipe manufacturing facility is a four-roll type squeeze roll comprising a pair of left and right side rolls and two upper left and right top rolls, or a five-roll type squeeze roll having a receiving roll. Further, a scraper device for squeeze rolls for removing deposits such as spatter and slag adhering to the inner corners of the left and right top rolls,
A scraper device for a squeeze roll, characterized in that a scraper made of a resin material having high heat resistance and wear resistance is provided so as to be in contact with the vicinity of the upper inner corner portion on the high-frequency heating portion side of the left and right top rolls.   The scraper device for a squeeze roll according to claim 1, wherein the scraper is made of MC nylon.   The scraper device for a squeeze roll according to claim 1 or 2, wherein the contact position where the scraper hits the top roll is within a range of 220 to 240 ° in the top roll rotation direction from the welding point.   The scraper has a plate shape, and a rake angle α which is an inclination angle of the scraper with respect to a tangential direction of the top roll as viewed from the longitudinal direction of the top roll axis is set to 30 ± 10 °. A scraper device for a squeeze roll according to any one of the above.   The scraper has a plate shape, and the torsion angle β, which is an inclination angle with respect to the roll width direction seen from the tangential direction of the top roll, is in the range of 0 to 5 °. The scraper apparatus for squeeze rolls in any one.   The scraper has a plate shape, and the torsion angle γ, which is an inclination angle of the scraper with respect to the roll width direction viewed from the outside in the top roll radial direction, is in the range of 0 to 5 °. A scraper device for a squeeze roll according to any one of claims 3 to 4.   The scraper has a plate shape, and the shape of the portion that contacts the top roll is L-shaped so as to come into contact with both the roll side surface and the roll circumferential surface that sandwich the corner portion of the top roll. The scraper apparatus for squeeze rolls in any one of 1-6.   A bracket with a long hole is attached to the front of the downward U-shaped holder yoke that supports the squeeze roll so that it can rotate directly. The scraper device for a squeeze roll according to any one of claims 1 to 7, wherein a scraper is attached to the bracket.   The scraper device for a squeeze roll according to claim 8, wherein a scraper is attached to the bracket via a taper block for adjusting a rake angle α of the scraper. The squeeze roll for a squeeze roll according to any one of claims 1 to 9, wherein the scraper is slidably attached to the bracket with an elastic member interposed between the scraper roll and an outer peripheral surface of the squeeze roll. Scraper device.

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