JPH06210492A - Method for welding steel plate in butt welding machine and butt welding machine - Google Patents

Abstract

PURPOSE:To uniformize welding strength and to control a reinforcement part by continuously measuring a groove interval from a welding starting vicinity to a welding completing vicinity during welding, and changing a butt amount so as to definitely keep the groove interval from the welding starting edge to the welding finishing edge corresponding to the variation. CONSTITUTION:By measuring a groove interval 5 during welding, the thermal contraction of a welding part at a welding time can be quantitatively obtained. Next, this thermal contraction amount is expressed in term of a butt position, if a change of the butt position at a present time point is generated against the butt position set at an initial time, the groove interval 5 in the time welding at the welding starting point and the groove interval 5 in the present welding time point can be made constant by moving the butt position set at initial time, that is, moving the butt position in the direction opposite to the thermal contraction direction, so this movement is continuously executed until the welding finishing time point, a metal structure uniform in the plate lateral direction can be formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a butt welding method and a butt welding machine at the time of butt welding of steel strips. More specifically, the groove interval changing during welding is always kept constant from the welding start end to the welding end. TECHNICAL FIELD The present invention relates to a welding method and apparatus for a steel plate to be welded.

[0002]

2. Description of the Related Art A side view of a conventional butt device is shown in FIG.
The plan view is shown in FIG. Generally, as a butting method in steel strip butt welding, a method is used in which the contact portion 7 of the arm provided at the lower part of the inlet side clamp and the fixed stopper 8 provided on the welding body are brought into contact with each other to maintain the groove interval 5. ing. Further, as an adjusting mechanism for changing the form at the time of cutting depending on the plate thickness and the composition of the steel strip, the fixed stopper 8 moves in the direction perpendicular to the direction in which the steel strip advances, and the groove interval at the time of butt adjustment is adjusted. A butt adjustment method is performed in which adjustment is performed by the motor 12 for. At this time, as a method of abutting the steel strips, the load cell 9 detects the pressure of the stopper as disclosed in Japanese Patent Publication No. 42800, and the movement of the inlet side clamp is performed until the pressure changes to a predetermined value. It is known how to do it.

[0003]

FIG. 6 shows a conventional state after welding, FIG. 7 shows a welding sectional view at a welding start point, and FIG. 8 shows a welding sectional view at a welding end point. In the butt method, it is possible to make the groove interval of the welding start point 15 and the end point 16 before the start of welding constant, but the groove interval becomes narrow due to heat shrinkage during welding, and the welding start point 15 and the end point 16 There was a problem in that there was a significant difference in the composition of the weld melted parts 17, 18 and the weld strength.

The reason why the groove interval becomes narrow is that as the welding progresses, that is, as the connection length becomes longer, the heat contraction due to the solidification of the melted portion increases the total pulling force between the plates and, as a result, approaches the end point. It is thought that it will become narrower. Further, it is considered that the reason why the welding strength is significantly different is that the twisting method of the filler wire and the base material is different as the groove interval is narrowed.

Further, in a butt joint device capable of freely changing the butt gap distance, the rattling amount of the moving stopper 8 tends to be noticeable due to the change of the groove gap. Then, this invention aims at providing the welding method and apparatus of the steel plate in the butt welding machine which solved the said problem.

[0006]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention is directed to a butt welding machine in which a trailing end portion and a trailing end portion of a preceding steel plate in a state of being clamped by an outgoing side clamp and an incoming side clamp. When performing butt welding after cutting the tip of the steel plate with a shear, continuously measure the groove interval from the vicinity of the start of welding to the vicinity of the end of welding,
A welding method for a steel plate in a butt welding machine, characterized in that the amount of butt is changed so as to keep the groove spacing between the welding start end and the end constant according to the amount of change, and the present invention is directed to the exit side. One of the above-mentioned clamps of the welding machine that performs butt welding after cutting the rear end of the preceding steel plate and the front end of the following steel plate in a state of being clamped by the clamp and the input side clamp as a moving clamp, In a butt welder including a fixed stopper for positioning the movable clamp and a butt cylinder for abutting the movable clamp with the fixed stopper, a groove interval is continuously maintained during welding from near the start of welding to near the end of welding. A butt welding machine characterized in that it is provided with a means for measuring and a means for controlling the amount of butt so as to keep the groove spacing constant according to the measured value. , More particularly, to attaching a position detector butt cylinder to align collision moving clamp fixed Suttopa, and provided the position detector transducer for transmitting to the controller converts the signal from the position detector,
And a butt welder configured to control the butt cylinder by transmitting an instruction from the controller to the hydraulically operated valve so as to keep the groove interval constant, or a load cell is attached to the fixed stopper, and A pressure converter for converting the signal from the load cell and transmitting it to the controller was provided, and an instruction from the controller was transmitted to the hydraulically operated valve so as to keep the groove interval constant, and the butt cylinder was controlled. It is a butt welder.

[0007]

In conventional steel strip welding, due to heat shrinkage during welding, the groove spacing at the end becomes narrower than that at the welding start end, the molten metal composition is different, and the welding excess at the end becomes large, so grinding must be performed. In addition to the decrease in welding strength, there were problems with cycle time.

According to the present invention, the amount of heat shrinkage of the welded portion at the time of welding can be quantitatively grasped by measuring the groove interval during welding or the pressure between the clamp and the stopper instead of this. Next, this quantitatively obtained amount of heat shrinkage is converted to the butt position, and if there is a change in the butt position at the present time with respect to the butt position that was initially set, By moving to the position, i.e. moving the butt position in the direction opposite to the heat shrink direction,
The groove interval when welding is performed at the welding start point and the groove interval at the current welding point can be made constant, and by continuing this until the welding end point, a uniform metallographic structure is formed in the plate width direction. can do.

For this reason, the welding starting point and the welding ending point have the same welding strength, and since the size of the welding extra portion can be made constant, grinding of the extra portion is unnecessary, improving the welding strength and shortening the cycle time. Will be able to.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an example of a matching logic of the present invention, and FIGS. 2 and 3 are diagrams of the matching device. In contrast to the conventional abutment device shown in FIGS. 4 and 5, the abutment device of the present invention has a position detector cylinder 6, a position detection converter 11, a controller 19 and a hydraulically operated valve 20 as shown in FIG.
There is a case where a load cell 9, a pressure converter 10, a controller 19 and a hydraulic operation valve 20 are newly added as shown in FIG.

The present invention will be described using an example of a laser welding machine. The end plate after being set in the clamp and cut with the shear is shown in Fig. 4.
It is located as indicated by the broken line. Next, the fixed side stopper 8 is adjusted so that the set groove interval is obtained, and then the butting is performed by the butting position detecting cylinder 6. The control in the butt flow shown in FIG. 1 is started from the time when the butt is completed, and welding is also started at the same time. During welding, the position of the moving clamp device 1 is monitored by the controller 19 via the position detection converter 11 with the cylinder 6 with a butt position detector. If it is different, an operation command is issued to the cylinder 6 with a position detector for abutment via the hydraulically operated valve 20 to adjust the position of the difference. This control is repeated from the welding start point to the welding end point. As a result of carrying out these things, the welding shape as shown in FIG. 7 could be obtained in all welding from the welding start point to the end point.

In the above embodiment, the cylinder 6 with the butt position detector is used. However, as shown in FIG. 3, the load cell 9 installed at the rear of the fixed stopper 8 to the pressure converter 10 is installed. It is also possible to monitor with a controller 19 via the hydraulic pressure control valve 20 and send an operation command to the butt cylinder via the hydraulically operated valve 20 to adjust the position of the difference. By the way, in the case of the pressure detection method, the pressure and position in this device are converted to 0.1 mm per ton.

Further, in the above embodiment, the inlet side clamp is adopted as the moving side clamp, but it goes without saying that the outlet side clamp may be adopted.

[0014]

According to the present invention, the position of the moving side clamp, that is, the groove interval is detected by, for example, a cylinder with a butt position detector or a load cell, and welding is performed at a constant groove interval from the start point to the end point. It has become possible to make the welding uniform and control the weld surplus area. In addition, the installed detector enables continuous monitoring of the machine condition, which has the effect of improving maintainability.

[Brief description of drawings]

FIG. 1 is a system diagram showing a matching logic of the present invention.

FIG. 2 is a side view of the matching device of the present invention.

FIG. 3 is a side view of the matching device of the present invention.

FIG. 4 is a plan view of a conventional matching device.

FIG. 5 is a side view of a conventional matching device.

FIG. 6 is an explanatory view showing a state after conventional welding.

FIG. 7 is a welding cross-sectional view at a welding start point.

FIG. 8 is a welding cross-sectional view at the welding end point.

[Explanation of symbols]

 1 Moving Clamping Device 2 Fixed Clamping Device 3 Strip 4 Bearing for Matching 5 Groove Interval 6 Cylinder with Position Sensor for Butt Matching 7 Stopper in Butt Clamp 8 Fixed Stopper 9 Load Cell 10 Pressure Transducer 11 Position Detector 12 Interval Adjusting motor 13 Butt cylinder 14 Welding fusion zone 15 Welding start point 16 Welding end point 17 Welding point at welding start point 18 Welding point at welding end point 19 Controller 20 Hydraulically operated valve

Claims (4)

[Claims] 1. In a butt welding machine, the butt welding is performed after cutting the rear end of the preceding steel plate and the leading end of the following steel plate clamped by the output side clamp and the input side clamp with a shear. At this time, the groove interval was continuously measured during welding from the vicinity of the start of welding to the vicinity of the end of welding,
A method for welding a steel plate in a butt welding machine, characterized in that the butt welding amount is changed so as to keep the groove interval between the welding start end and the welding end constant according to the amount of change. 2. The welding machine according to any one of the preceding claims, wherein the rear end portion of the preceding steel sheet and the leading end portion of the following steel sheet clamped by the outlet side clamp and the inlet side clamp are cut by a shear and then butt welded. In a butt welder equipped with a fixed stopper for positioning the movable clamp and a butt cylinder for abutting the movable clamp with the fixed stopper, a groove from the start of welding to the end of welding is used. A butt welding machine comprising means for continuously measuring the distance during welding and means for controlling the amount of butt so as to keep the groove distance constant according to the measured value. 3. A position detector is attached to an abutting cylinder that abuts the movable clamp with a fixed stopper, and a position detector converter for converting a signal from the position detector and transmitting it to a controller is provided and opened. 3. The butt welding machine according to claim 2, wherein an instruction from the controller is transmitted to the hydraulically operated valve to control the butt cylinder so as to keep the leading distance constant. 4. A fixed stop is equipped with a load cell,
Further, a pressure converter for converting the signal from the load cell and transmitting it to the controller is provided, and an instruction from the controller is transmitted to the hydraulically operated valve so as to keep the groove interval constant, and the butting cylinder is controlled. The butt welding machine according to claim 2, wherein