JP2006205176A - Method and device for straightening - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an efficient method and a device for straightening at a high-speed, which requires no water for cooling after heating. <P>SOLUTION: The device comprises a square frame 12 installed on a work 100, a plasma torch 11 movably provided within the frame 12 in the longitudinal direction and the transverse direction, a heating surface copying mechanism 30 which is arranged in a vicinity of the plasma torch 11 to maintain the constant distance of stand-off between the plasma torch 11 and the work 100, and a control device 56 to control longitudinal and transverse driving devices 13, 14 of the plasma torch 11 based on the heating condition set for each thickness and each heating method in advance, and corrects the welding distortion by moving the plasma torch while using a plasma arc to heat the part, where the distortion is formed by the welding. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a distortion removing method and apparatus for correcting welding distortion generated in a plate material by welding, and in particular, welding distortion generated in an aluminum plate material when manufacturing a structure mainly made of aluminum such as an aluminum ship. The present invention relates to a distortion removing method and an apparatus suitable for correcting the above.

  In the manufacturing process of large structures such as shipbuilding and bridges, reinforcing members such as stiffeners are welded to structural members, and strain along with the so-called lean horse strain often occurs along this weld line. Further, in a thin plate or the like, out-of-plane deformation due to welding distortion frequently occurs. These distortions may affect not only the appearance performance but also the design strength, which is a very important problem in quality control. Therefore, in order to correct such welding distortion, the following distortion removing techniques have been proposed.

For example, in Patent Document 1, a remote control box is connected to a carriage equipped with a heating TIG torch to operate the entire apparatus. At this time, the distortion is corrected by rapidly cooling the target member after heating it with a TIG torch while moving the carriage in a predetermined direction.
In Patent Document 2, a control device is mounted on a carriage equipped with a heating gas burner, and the lean horse strain is removed by heating using numerical data based on the weld line.
In Patent Document 3, a heating TIG torch is attached to one side of a traveling carriage via a mechanism that keeps the distance between the torch tip and the heating unit constant. Moreover, it has a mechanism that swings the torch, and the distortion is corrected by weaving heating and rapid cooling while moving the carriage.

JP 59-45093 A JP-A-5-177254 JP-A-8-206872

  However, in the above-described prior art, a gas flame or a TIG arc is mainly used as a heat source for strain relief, and it is necessary to perform forced quenching by water cooling or the like. There is a problem that a water tank or the like is required, and the apparatus becomes complicated and large. In addition, distortion removal using these heat sources has problems such as a slow heating rate and poor production efficiency.

Moreover, in the distortion removal apparatus of patent document 1, 3, it is necessary to move a trolley | bogie main body for the production | generation of a heating wire track | truck, and monitoring by an operator is always needed during heating construction. In addition, since the accuracy of the heating wire depends on the linearity of the carriage, it is difficult to ensure the accuracy with the method of running on the plate where the distortion is generated (particularly, the accuracy of the position of the heating wire is required in the case of thinning the lean horse). ) Also, if there are any obstacles on the heating surface, it cannot be constructed by the cart system.
On the other hand, in Patent Document 2, since the position of the burner is numerically controlled by the moving device attached to the carriage, the accuracy of the heating position is guaranteed, but basically only the heating in the vertical posture can be performed and the versatility is lacking. Moreover, since this apparatus is specialized for linear heating, a heating method such as so-called Matsuba-yaki that corrects out-of-plane deformation cannot be adopted.

  In Patent Documents 1 and 3, the heating conditions (current value, heating rate, etc.) at the time of construction are set manually, and are adjusted according to the situation such as distortion and plate thickness of the target member. For this reason, a certain level of skill is required to operate these strain relief devices, and it is difficult to ensure the stability of the processing quality.

  In the prior art, most devices are aimed at automating linear heating. Further, even in the apparatus of Patent Document 3 having a swing function, the torch portion is driven by an air cylinder, so that an arbitrary weaving pattern suitable for the target member cannot be realized.

  Moreover, in patent document 1, in order to hold | maintain the distance (standoff) between a TIG torch and a workpiece | work uniformly, the TIG torch is being fixed to the member supported at both ends with the ball caster. However, since the distance between the mounting position of the TIG torch and the support portion is large, the standoff varies on the deformed plate surface. On the other hand, in patent document 3, in order to avoid the fluctuation | variation of a standoff, the holding device with which the ball caster was attached to the heating torch is being fixed. In this method, the stand-off is kept constant, but there is a possibility that the ball caster may damage the surface immediately after heating, which causes a problem in construction quality. In addition, since the tip of the torch is surrounded by the holding device, the range of torch movement is limited and the dead space is increased. On the other hand, in Patent Document 2, position control is performed using a touch sensor in order to make the standoff constant, but a special sensor and a control axis are added for this function, and the apparatus is complicated and expensive. turn into.

  Further, Patent Documents 1 and 3 basically target a plate material that can travel on a carriage, and have a structure that allows only downward heating construction. On the other hand, in Patent Document 2, it is premised that the wall surface of the structure is heated upright, and is not versatile. In actual construction sites, there are mostly cases where both downward and vertical constructions are mixed, and it is necessary to be able to cope with both construction methods.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an efficient strain removing method and an apparatus thereof that do not require water cooling after heating.
Another object of the present invention is to provide a strain removing device that has a simple structure and is easy to handle, and that can be applied under appropriate heating conditions and heating patterns in accordance with the plate thickness and strain conditions.

The strain relief method according to the present invention corrects welding distortion by moving a plasma torch while heating a portion of a work where welding distortion has occurred with a plasma arc.
In the present invention, by using a plasma arc with high heat concentration as a heat source for strain relief, efficient strain relief that does not require water cooling after heating can be performed.

In the strain relief method of the present invention, a plurality of heating patterns are set in advance for each heating method as heating conditions for each plate thickness, and heating is performed by selecting one heating pattern from among them. In this case, the plurality of heating patterns include at least a linear heating pattern and a weaving heating pattern.
By applying a linear heating pattern, it is possible to mainly correct angular deformation (lean horse distortion), and the weaving heating pattern can mainly correct out-of-plane deformation.
Furthermore, when the strain relief method of the present invention is applied to the correction of the welding distortion of an aluminum material, it is very effective for strain relief when manufacturing an aluminum structure such as an aluminum ship.

  In addition, a distortion removing device according to the present invention is disposed in the vicinity of a rectangular frame installed on a workpiece, a plasma torch that is movable in the vertical and horizontal directions within the frame of the frame, and the plasma torch. A heating surface copying mechanism that maintains a constant standoff distance between the plasma torch and the workpiece, and a vertical and horizontal driving device for the plasma torch that is set in advance for each plate thickness and each heating method. And a control device that performs control based on the above.

  With this configuration, the strain relief method of the present invention can be carried out, the structure is simple and handling is easy, and the strain relief of a large workpiece can be appropriately performed according to the plate thickness and the strain situation. It can be applied under heating conditions and heating patterns.

  In the strain relief device of the present invention, it is preferable that an operation unit for setting and selecting the heating condition is provided on the frame. As a result, the heating conditions can be set immediately on the spot.

  Further, a linear heating pattern and a weaving heating pattern are set in the control device as heating conditions for each plate thickness, and the control device uses the operation unit as a starting point of a heating trajectory as the linear heating pattern. By designating the end point, a linear heating line is automatically generated. Furthermore, the control device is configured to automatically generate the other linear heating line with respect to the linear heating line by designating an offset amount from the starting point of the heating trajectory by the operation unit.

  The weaving heating pattern includes a straight line portion and an arc portion, and is defined by a weaving width and a weaving length. By specifying a heating line interval in the operation unit, the control device The weaving heating pattern is automatically developed in the rectangular range defined by the diagonal reference points at the designated heating line interval.

In the present invention, the main body portion of the strain relief device is leaned against a standing plate of a workpiece with a fixing jig.
By leaning the main body portion of the strain relief device against the workpiece standing plate with a fixing jig, the same strain relief device can be used to strain the standing plate such as a wall surface in a standing posture.

  According to the present invention, since a plasma arc with high heat concentration is used as a heat source for strain relief, efficient strain relief that does not require forced cooling such as water cooling after heating can be performed. In addition, it is possible to easily remove the strain of a large workpiece.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a configuration diagram of a system including a strain relief device of the present invention, FIG. 2 is a plan view of the strain relief device of the present invention, FIG. 3 is a side view of the strain relief device, and FIG. FIG. 5 is a front view of the torch portion of the strain relief device, FIG. 6 is a side view of the torch portion, and FIG. 7 is a plan view of the torch portion.

In the present invention, a plasma arc having higher heat concentration than that of a gas burner or a TIG arc, that is, a high energy density is used as a heat source for removing distortion of the workpiece 100, particularly an aluminum material. As a means for generating plasma arc, a plasma welding power source generally used for plasma welding is used.
This system is configured by connecting a plasma welding power source 50, a plasma torch cable 52, a cooling device 54, a control device 56, and the like to a strain relief device 10 having a plasma torch 11 movable in the vertical and horizontal directions. Yes.

The distortion removing device 10 includes a square frame 12 installed on a workpiece 100, and the frame 12 is provided with a vertical driving device 13 and a horizontal driving device 14 for the plasma torch 11. The longitudinal drive device 13 includes a longitudinal linear guide 15 disposed on a longitudinal member on one side of the frame 12, a longitudinal drive shaft 16 formed of a ball screw rotatably provided in the longitudinal linear guide 15, and It is mainly composed of a longitudinal drive motor 17 composed of a servo motor that rotationally drives the longitudinal drive shaft 16. In the lateral drive device 1, both end portions are supported on a longitudinal linear guide 15 and a longitudinal member on the other side of the frame 12 via a traveling device 18 including a cam follower, and one end portion is supported by the longitudinal drive shaft 16. A lateral drive motor comprising a coupled lateral linear guide 19, a lateral drive shaft 20 comprising a ball screw rotatably provided in the lateral linear guide 19, and a servo motor for rotationally driving the lateral drive shaft 20. 21 and a torch holder 22 of the plasma torch 11 coupled to the lateral drive shaft 20.
Accordingly, the plasma torch 11 held downward by the torch holder 22 is moved in an arbitrary orbit within the frame of the rectangular frame 12 by controlling the rotation of the vertical driving device 13 and the horizontal driving device 14 with two degrees of freedom. be able to. Here, the movable range of the plasma torch 11 is 700 mm long × 400 mm wide.

Further, the strain relief device 10 has an operation unit 23 for inputting and displaying heating conditions including a heating pattern, and further has a configuration in which the weight is suppressed to about 250 N and handling is easy. By tilting about 30 degrees by a caster 24 attached to the front, the cart can be easily moved and transported.
2 to 4, reference numeral 25 denotes stand portions provided at the four corners of the frame 12, and the present strain removing device 10 is installed on the work 100 through the stand portions 25. 26 is a cable bearer, and 27 is a support for holding the plasma torch cable 52.

Next, the detailed structure of the torch part is shown in FIGS. The torch portion includes a heating surface copying mechanism 30 for maintaining a constant arc length (standoff) that affects the stability of the plasma arc. The heating surface copying mechanism 30 is disposed in the vicinity of the plasma torch 11 and is configured to copy the vicinity of the heating surface of the workpiece 100 as will be described later. Specifically, the configuration is provided on a slider 31 provided with a torch holder 22 for holding the plasma torch 11 via a spring 34 for biasing a copying rod 33 provided with a ball caster 32 at the tip. It is a configuration. The spring 34 is mounted between the slider 31 and the ball caster 32, so that the ball caster 32 at the tip of the copying rod 33 is always pressed against the surface of the workpiece 100 (near the heating surface), and between the plasma torch 11 and the workpiece 100. The standoff distance Ls can always be kept constant. In addition, the ball caster 32 does not damage the surface of the workpiece 100. Further, the scanning rod 33 is freely moved up and down by a spring 34 within a range of, for example, ± 10 mm, and can sufficiently follow out-of-plane deformation and angular deformation of the workpiece 100. Yes, it is possible to accurately follow the contact type without using a special sensor or the like. Incidentally, follow-up range L _R of the copying rod 33 is also shown in FIG.

Further, the plasma torch 11 attached to the slider 31 via the torch holder 22 can be moved in the torch direction (vertical direction) by an adjusting screw 36 which is a torch direction position adjusting means. The adjustment screw 36 is a self-holding trapezoidal screw and is provided on the guide frame 35 of the slider 31. Thereby, the slider 31 and the plasma torch 11 have a stroke of ± 50 mm, for example. Therefore, even if there is an interference such as a stiffener having a height of about 100 mm on the workpiece 100, heating can be performed from the back side of the stiffener without any trouble. Further, the tip position of the plasma torch 11 from the surface of the workpiece 100 is adjusted by the adjustment screw 36. Thereby, the standoff distance can be adjusted within a range of 3 to 13 mm. Incidentally, the copying rod 33 is disposed in the vicinity of the plasma torch 11 (diagonally forward in a plan view), the distance L _T between the torch center and copying rod 33 is set to approximately 80mm on the basis of the test data of FIG. 15 described later Yes. Reference numeral 37 denotes a knob of the adjustment screw 36, and reference numeral 38 denotes a guide shaft of the slider 31.

  The control device 56 shown in FIG. 1 includes a programmable controller (hereinafter referred to as PC), and controls the vertical direction driving device 13, the horizontal direction driving device 14, and the plasma welding power source 50 of the plasma torch 11. Generally, a PC has a nonvolatile memory and can hold various data. Further, as shown in FIG. 2, the strain relief device 10 is equipped with an operation unit (touch panel type operation box) 23 for inputting and displaying heating conditions, heating patterns, and the like. The heating conditions are a current value, a heating rate, and a heating pattern, and are set in advance for each plate thickness and each heating method. The heating pattern is mainly a linear heating pattern and a weaving heating pattern. At the time of heating construction, an appropriate condition is selected from these preset heating conditions according to the thickness of the workpiece 100 and the state of occurrence of distortion.

  FIG. 8 is an explanatory view showing a linear heating method. FIG. 8A is a plan view and FIG. 8B is a side view. In the linear heating operation, the start point and end point position of the heating trajectory are taught by the operation unit 23 as shown in FIG. Thereafter, when the automatic operation is started, the pilot arc is turned on, the plasma torch 11 is moved to the starting point teaching position, and is heated and moved toward the end point. The heating conditions and timing at this time can be arbitrarily set by the operation unit 23. Further, since the linear heating pattern is mainly applied to correction of the lean horse distortion generated in the T-joint fillet welding as shown in FIG. 8, normally two linear heating lines 41 and 42 are generated. . At this time, by setting the offset amount S from the start point in advance, it is possible to automatically generate the two linear heating lines 41 and 42 only by specifying the start point and the end point of one of the linear heating lines 41. Can do.

9 is an explanatory view showing a weaving heating method, FIG. 10 is an explanatory view showing the development of the weaving heating pattern in the construction range, and FIG. 11 is an explanatory view showing the development of the weaving heating pattern in an arbitrary heating line direction.
The weaving heating operation is realized by developing a weaving heating pattern defined by the weaving width A and the weaving length L within the movable range of the plasma torch 11 as shown in FIG. As shown in FIG. 9, the weaving heating pattern is composed of a straight line portion and an arc portion, and each weaving composing point is defined on the weaving coordinate system {W} as shown in the table of FIG. In this distortion removing device 10, ten kinds of such weaving heating patterns are preset. This weaving heating pattern is developed by designating a heating line interval in a rectangular range 43 defined by a home reference point and a diagonal reference point that can be arbitrarily set as shown in FIG. At this time, the weaving heating pattern is developed from the home reference point side, and the trajectory of the weaving heating pattern that protrudes from the development range 43 as shown by the heating line d in FIG. 10 is not generated. As shown in FIG. 10, the heating line direction can be selected from a vertical direction parallel to the vertical drive shaft 16 and a horizontal direction parallel to the horizontal drive shaft 20. Regarding the construction order of the weaving heating pattern, the order from the home reference point (a → b → c), the order from the center to the outside (b → a → c), and the order from the outside to the center (a → c → b) ) Can be selected.

Further, the weaving heating pattern is not only parallel to the drive shaft, but can also be developed in an arbitrary direction as shown in FIG. Each weaving composing point at this time can be easily obtained by the equations (1) and (2). Here, ^R T _W is a homogeneous transformation matrix to the home reference point weaving coordinate system as viewed from the device coordinate {R} with the origin (or the work coordinate system) {W}. Θ is the rotation angle around the Z axis, and x and y are the starting points of the weaving heating pattern on {R}. Moreover, the conditions of the weaving heating pattern, the arc ON timing, and the weaving heating pattern can be arbitrarily set similarly to the linear heating.

Next, the operation of the strain relief device 10 configured as described above will be described. For example, as illustrated in FIG. 12, the workpiece 100 is configured by welding a longe 102 and a transformer 103 to a plate 101 with a fillet joint. 12A is a plan view, and FIG. 12B is a side view. In FIG. 12, O is the origin of the workpiece coordinate system.
When welding distortion occurs in the plate 101 of such a workpiece 100, as shown by the hatched portion in FIG. This strain relief device 10 is set in one construction section. At this time, the distance (offset) of the plasma torch 11 from the surface of the plate 101 is adjusted to a predetermined value by the adjusting screw 36 in advance. Then, the current value, the heating speed, the heating pattern, the heating direction, and the like corresponding to the plate thickness of the plate 101 among the preset heating conditions (current value, heating rate, heating pattern, etc.) are controlled by the operation unit 23. Select. When the automatic operation is started, the plasma torch 11 controls the longitudinal driving device 13 and the lateral driving device 14 by the control device 56, thereby distorting the plate 101 with the selected heating pattern within the frame 12. Move while heating the location. This corrects the weld distortion.

(1) Heat source for strain relief Here, the significance of using a plasma arc as a heat source for strain relief will be described. The result of verifying the amount of heat deformation by plasma arc on the aluminum plate by experiment (natural cooling) is shown. The horizontal axis is the heat input parameter (a value obtained by dividing the heat input per unit length of the heating wire divided by the square of the plate thickness), and the amount of horizontal shrinkage (the distance from the heating point is the plate thickness). FIG. 13 and FIG. 14 show distributions when the vertical axis represents the divided value) and the amount of angular deformation. The aluminum plate was tested for plate thicknesses of 4 mm, 5 mm, 6 mm, and 8 mm.
From this result, it was found that the amount of angular deformation was maximized when the heat input parameter was around 4 (J / mm ³ ). However, the heating condition in which the amount of angular deformation is maximized is set to an appropriate value on the premise that no melt mark remains in the actual heated surface state from the construction quality. The heating rate at this time is about 750 cpm to 125 cpm, which is about 10 times faster than the heating rate of 10 cpm during general TIG heating. In addition, in the case of heating by plasma arc, forced cooling such as water cooling is not necessary at all, and natural cooling may be sufficient. Therefore, the apparatus configuration can be made extremely compact, and the welding distortion of the workpiece can be corrected efficiently.
Further, the appropriate value for each plate thickness obtained in this experiment is preset in the control device 56 as described above.

(2) Heating operation When angular deformation (so-called lean horse distortion) occurs in the plate 101, a linear heating pattern is mainly selected and applied as the heating pattern by the operation unit 23. The linear heating pattern is automatically generated by the control device 56 by designating the start point and end point positions of the heating trajectory with the operation unit 23 as shown in FIG. No. 2 or No. In the case where the linear heating pattern is automatically generated in the five partitioned areas, it is only necessary to set the offset amount S from the start point by the operation unit 23 based on the weld line data of the fillet joint of the longe 102.
On the other hand, when out-of-plane deformation occurs in the plate 101, a weaving heating pattern as shown in FIG. 9 is mainly applied as the heating pattern. By specifying the plate thickness and the weaving number at the time of heating construction, the heating operation can be executed with the preset heating conditions and the weaving heating pattern. The weaving heating pattern is automatically developed in a rectangular development range composed of a home reference point and a diagonal reference point by specifying a heating line interval. Further, the timing from the start of movement of the plasma torch 11 to the arc ON and the crater processing (current is gradually reduced) time generated at the end of heating can be arbitrarily set by the operation unit 23.
The heating rate is constant. However, in the case of the weaving heating pattern, the linear velocity is controlled to be constant. Further, the weaving heating pattern and the linear heating pattern usually have different heating rates. The heating rate is set by the operation unit 23.

(3) Heating surface copying operation The heating surface copying mechanism 30 constantly presses the scanning rod 33 against the surface of the plate 101 (near the heating surface) by the spring 34 to keep the distance (standoff) between the plasma torch 11 and the plate 102 constant. keeping. If the distance between the scanning rod 33 and the plasma torch 11 is wide, it is difficult to keep the standoff constant. Therefore, it is advantageous to make the two as close as possible. However, if the scanning rod 33 and the plasma torch 11 are too close, there is a risk of damaging the surface of the plate 101 immediately after heating. Therefore, the optimum interval was obtained by experiment and thermal analysis.
FIG. 15 shows the maximum temperature distribution with respect to the distance from the heating wire for an aluminum plate (plate thickness: 4 mm). As a result, in the case of an aluminum plate material, it was confirmed that if the distance between the copying rod 33 and the plasma torch 11 is 80 mm, the surface temperature is around 80 degrees, and the copying rod 33 is not damaged.

  Again in FIG. When heating of the divided area of 1 is completed, The distortion removing device 10 is carried and set in the two partitioned areas. After that, as in the above, No. Heating is applied to the strain occurrence point in the partition area 2. Thereafter, in the same manner, no. 3, no. 4, ... No. What is necessary is just to heat-process about 16 and each division area. In addition, the order of the heating work in the partitioned area is not limited to the vertical direction of the workpiece 100 as shown in FIG. 12, and may be performed in the horizontal direction in order, and arbitrarily heated from the partitioned area where the occurrence of distortion is large. May be performed. In the above description, the heating work is performed from the front side of the workpiece 100. However, the heating work can be performed from the back side by turning the work 100 upside down. In this case, the distortion removing device 10 may be set on the longage 102 by applying a so-called getter. Then, the plasma torch 11 is set so as to be lowered by the adjusting screw 36 so as to maintain a predetermined stand-off.

  Since this distortion removing device 10 is lightweight and has a caster 24 attached to the front portion of the frame 12, it is convenient to carry and the operation unit 23 is attached to the frame 12, so that The applied heating conditions, heating pattern, etc. can be set immediately, making it extremely easy to use.

  Next, FIG. 16 is a side view showing a strain relief device according to another embodiment of the present invention. In the above-described embodiment, the plasma torch 11 is heated in a downward posture, but in this embodiment, the plasma torch 11 is in a standing posture. That is, the welding distortion of the standing plate 104 of the workpiece 100 can be corrected. The configuration of the main body portion of the strain relief device 10 is exactly the same as that described above, and is configured such that the frame 12 of the strain relief device 10 is supported by an appropriate fixing jig 60 and leans against the standing plate 104. The fixing jig 60 includes, for example, a telescope-type column 61 provided with a compression spring therein, a fixture 62 pin-coupled to the upper end of the column 61 to fix the column 61 to the frame 12, and a column The suction pad 63 is provided at the lower end of 61. Since the main body portion of the strain relief device 10 can be leaned against the surface of the standing plate 104 of the workpiece 100 by the fixing jig 60, the welding distortion generated in the standing plate 104 can be corrected by the same operation as in the above-described embodiment. Can do.

In the above embodiment, although the example applied mainly to an aluminum structure was shown, the application to the heat distortion removal construction of structures other than aluminum accompanied by lean horse distortion or out-of-plane deformation is also possible. However, in this case, it is necessary to select a heat source suitable for the characteristics of the target member.
Further, regarding the weaving heating pattern, in the case of the above-described embodiment, it is realized by an S-shaped trajectory combining a straight line and a circular interpolation trajectory, but other patterns such as a sine wave and a rectangular wave can be easily generated. be able to. Furthermore, a heating method such as Matsuba-yaki, which is a general construction method, can be realized.
Further, although the heating surface copying mechanism has been described with a mechanical scanning system using a scanning rod having a ball caster at the tip, a non-contact scanning mechanism using an ultrasonic sensor, a laser sensor, or the like may be used.
In addition, the plasma torch moving mechanism of the strain relief device can be configured as a cantilevered orthogonal T type or scalar type.

The block diagram of the system provided with the distortion removal apparatus of this invention. The top view of the distortion removal apparatus of this invention. The side view of a distortion removal apparatus. The front view of a distortion removal apparatus. The front view of the torch part of a distortion removal apparatus. The side view of a torch part. The top view of a torch part. Explanatory drawing which shows the linear heating method. Explanatory drawing which shows the weaving heating method. Explanatory drawing which shows expansion | deployment to the construction range of a weaving heating pattern. Explanatory drawing which shows expansion | deployment to the arbitrary heating line directions of a weaving heating pattern. Explanatory drawing of the distortion removal method by the distortion removal apparatus of this invention. The graph which shows the relationship between the heat input parameter in the case of an aluminum plate material, and lateral shrinkage. The graph which shows the relationship between the heat input parameter and the amount of angular deformation in the case of an aluminum plate. The graph which shows the relationship between the distance from a heating wire, and the highest ultimate temperature in the case of an aluminum plate. The side view which shows the distortion removal apparatus of other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Distortion apparatus 11 Plasma torch 12 Frame 13 Longitudinal drive apparatus 14 Lateral drive apparatus 15 Longitudinal linear guide 16 Longitudinal drive shaft 17 Longitudinal drive motor 18 Traveling apparatus 19 Lateral linear guide 20 Lateral drive shaft 21 Lateral direction Drive motor 22 Torch holder 23 Operation unit 24 Caster 25 Stand unit 30 Heating surface copying mechanism 31 Slider 32 Ball caster 33 Copying rod 34 Spring 35 Guide frame 36 Adjusting screw 37 Knob 41 Linear heating wire 42 Linear heating wire 43 Weaving heating pattern Development range 50 Plasma welding power source 56 Control device 60 Fixing jig 100 Work 101 Plate 102 Longi 103 Transformer 104 Standing plate

Claims (11)

  A distortion removing method comprising correcting a welding distortion by moving a plasma torch while heating a portion of a workpiece where welding distortion has occurred with a plasma arc.   2. The distortion removing method according to claim 1, wherein a plurality of heating patterns are set in advance for each heating method as heating conditions for each plate thickness, and heating is performed by selecting one heating pattern from the heating patterns. .   The distortion removing method according to claim 2, wherein the plurality of heating patterns include at least a linear heating pattern and a weaving heating pattern.   A strain relief method, wherein the strain relief method according to any one of claims 1 to 3 is applied to correction of welding distortion of an aluminum material. A rectangular frame installed on the workpiece;
A plasma torch provided movably in the vertical and horizontal directions within the frame;
A heating surface copying mechanism that is disposed in the vicinity of the plasma torch and maintains a constant standoff distance between the plasma torch and the workpiece;
A control device for controlling the vertical and horizontal driving devices of the plasma torch based on heating conditions set in advance for each plate thickness and for each heating method;
A strain relief device characterized by comprising:   6. The distortion removing apparatus according to claim 5, wherein an operation unit for setting and selecting the heating condition is provided on the frame.   The distortion removing device according to claim 5 or 6, wherein a linear heating pattern and a weaving heating pattern are set in the control device as heating conditions for each plate thickness.   The control device is configured to automatically generate a linear heating line by designating a start point and an end point of a heating trajectory with the operation unit as the linear heating pattern. 8. The strain relief device according to any one of items 7.   The controller is configured to automatically generate the other linear heating line with respect to the linear heating line by designating an offset amount from a starting point of a heating trajectory with the operation unit. Item 9. A strain relief device according to Item 8.   The weaving heating pattern is composed of a straight portion and an arc portion, and is defined by a weaving width and a weaving length. The distortion removing apparatus according to any one of claims 5 to 7, wherein the weaving heating pattern is automatically developed in a square range defined by a reference point at the specified heating line interval. . 11. A strain relief device, wherein the body portion of the strain relief device according to claim 5 is leaned against a standing plate of a workpiece with a fixing jig.

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