JPH03270812A - Electric resistance welded steel pipe inner surface bead cutting position control method - Google Patents

Abstract

PURPOSE:To improve a product yield through the realization of a proper bead cutting when the cutting position of an inner surface bead that is generated at the time of the manufacture of an electric resistance welded steel pipe, is controlled, by conducting the position control of a cutting tool by measuring the shape of the cut bead. CONSTITUTION:A plate thickness direction tolerance and the height of a cutting tool 4 which are equivalent to the size of an electric resistance welded steep pipe to be cut, are set at a bead cutting shape setter 13, and each of them is inputted into an operator 14. Next, a bead shape signal detected by means of a shape detector 11 is inputted into the operator 14 thorough a bead shape measurer 12. The right and left surplus widths of a bead are compared with each other by the operator 14, and in the case of both being different, a motor 7 is controlled through a regulator 15 so that both may become equal to each other, and the angle of a retaining member 1 is regulated. Next, a fluid pressure cylinder 9 is operated by using the bead right and left surplus width values so that the height of the cutting tool 4 may become proper.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for controlling the cutting position of a bead on the inner surface of a 1itk111 tube.

<Prior art> Normally, weld beads generated during the production of electric MjIl pipes are
It is generally removed by cutting immediately after welding, but since the shape of the cut affects quality aspects such as the strength of the pipe, control values for wall thickness are often specified.

In particular, for the inner bead, it is necessary to reduce the pressure loss due to the resistance of the fluid flowing inside the pipe as much as possible, so the tolerance Δt (m) in the plate thickness direction is determined by the wall thickness t (sw++
), the following three standards are determined based on the pipe outer diameter. That is, ■ t-0,2≦ΔL≦L +0.
2 ■ 1+0≦Δt≦t+0.2 ■−1−0.2≦Δt≦1−0.

By the way, in order to maintain such strict standards for the inner bead, it is necessary to constantly monitor the width and height of the bead cutting surface, but since it cannot be directly observed from the outside because it is the inner surface of the tube. Various measuring devices have been proposed.

One of the representative examples is JP-A-571370, for example.
There is one that utilizes the optical cutting method disclosed in Japanese Patent No. 27. The process involves irradiating the cut surface with a slit light after bead cutting, detecting the light cutting profile obtained on the cut surface using an optical image receiving means, and comparing it with a pre-given standard inner surface shape. The purpose is to determine the cutting status of the bead.

<IIA to be Solved by the Invention> However, since the surface to be cut after bead cutting of a pipe is almost the same as a mirror surface, there are the following drawbacks when using the above-mentioned optical cutting method.

In other words, if you aim a light source at a certain angle onto the surface to be cut, and set up the camera vertically to detect the diffusely reflected light, you can determine the width of cut, but you cannot determine the depth of cut. . Furthermore, even if a camera is installed to detect specularly reflected light, it is still possible to measure the cutting width, but it is not possible to measure the cutting depth.

The present invention has the above-mentioned prior art! This invention was made to solve the problem I, and aims to provide a method capable of measuring and controlling the shape of a surface to be cut without using the optical cutting method.

<Means for Solving the Problems> The present invention provides a cutting [! a Step of measuring the shape of the inner bead of the steel pipe, a step of comparing and calculating the measured value of the measured inner bead shape with a pre-given setting value, and determining the cutting angle of the cutting tool based on the result of the comparison calculation. and a step of adjusting the height of the bead.

<Function> According to the present invention, the shape of the cut inner bead is measured and the measured value is compared with the reference setting value, so the cutting tool is adjusted to obtain the proper bead shape. The cutting angle and its height can be adjusted.

<Examples> Examples of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a side view, partially in section, showing an embodiment of an inner bead cutting position control device according to the method of the present invention.

In the figure, 1 is a holding member in which an upper roller 2 and a lower roller 3 that abut against the inner surface of the ERW steel pipe P in the vertical direction with a constant force and a cutting tool 4 that cuts the inner bead are integrally incorporated. It is.

Reference numeral 5 denotes a holder for positioning the holding member 1 from outside the tube, and an operating arm 6 is attached to the end of the holder. A fan-shaped gear 6a is provided at one end of the operating arm 6, and this fan-shaped gear 6a meshes with a circular gear 8 rotated by a motor 7, as shown in detail in the AA arrow view of FIG. It is said to be able to rotate freely.

Reference numeral 9 denotes a fluid pressure cylinder that allows the cutting tool 4 to be raised and lowered in the vertical direction.

Reference numeral 10 denotes a bead shape detector constructed of, for example, an optical fiber type light emitter/receiver, which is attached so as to fit into a bead passage 11 provided in the holding member 1.

12 is a bead shape measuring device, and a bead shape detector 1
The bead shape signal detected in the holding member 1 and the holder 5
It is manually powered via line a, which is drawn out through the line a.

I3 is the tolerance ΔL (mm
) and the height hs (mm) of the cutting tool 4.

14 is the bead shape ill from the bead shape measuring device 12
This is a calculation unit that calculates the appropriate position of the cutting tool 4 by comparing the fixed value with the bead cutting shape setting value from the bead cutting shape setting device 13.

Reference numeral 15 denotes an adjuster, which controls the angle of the holding member 1 via the motor 7 based on the position signal of the cutting hide 4 calculated by the calculator 14, and adjusts the cutting angle of the cutting tool 4 to the beat. , through the line to the hydraulic cylinder 9
The height position of the cutting tool 4 can be adjusted by operating the cutting tool 4.

Next, the operation of the inner bead cutting position control device configured as described above will be explained.

First, the tolerance Δt in the plate thickness direction corresponding to the size of the ERW steel pipe to be cut by the bead cutting shape setting device 13 and the cutting tool 4
, and are input to the calculator 14 respectively.

Next, the bead shape signal detected by the shape detector 11 is input to the calculator 14 via the bead shape measuring device 12.

FIG. 3 shows an example of a bead shape measured by the bead shape measuring device 12, which is recognized as the bead width W and the left and right margins XI and Xg of the bead. Note that W is the bead cutting width, which is approximately the same value as the blade width of the cutting tool 4.

Then, in the arithmetic unit 14, first, the left and right margin x of the bead is
Compare 1 and X.

(a) If the left and right margins Xl and Xt are different as shown in Figure 4 (a), make sure that they are equal, that is, )[+! ] [1・−・・・・−・・−・・・・−・・・
-・(1), the motor 7 is connected via the regulator 15 so that
is controlled to adjust the angle of the holding member 1. As a result, the cutting angle of the cutting tool 4 to the bead is adjusted.

(b) Next, the left and right margin of the bead X1. Using the value of Xg, operate the fluid pressure cylinder 9 so that the set height of the cutting tool 4 is expressed by the following formula.

h s = (x + + x t ) / 2 --
−−−−−−−−(2) When adjusting the set height, if the tolerance ΔL is
+0≦Δmu≦t If +0.2, cutting tool 4
It is necessary to set the set height to -0.1 m from the inner surface of the tube, but first change the position of the cutting tool 4, measure the height direction position where = 0, and then change the height from that position to 0.1 m. 1 v
All you have to do is lower it.

(C) Furthermore, as shown in FIG. The shape detector 11 detects the left and right margin XI + From this, adjustments are made so that the above equation (1) is satisfied.

<Effects of the Invention> As explained above, according to the present invention, since the shape of the cutting bead is measured and the position of the cutting tool is controlled, proper bead cutting can be realized. , contributes to improving product yield.

[Brief explanation of drawings]

FIG. 1 is a side view, including a partial cross section, of an embodiment of the inner bead cutting position control device according to the method of the present invention, FIG. 2 is a view along arrow A-A in FIG. 1, and FIG. 4 is an explanatory diagram of the shape of the cutting bead, and FIGS. 4(a) and 4(b) are characteristic diagrams showing the measured shape of the cutting bead. ■...Holding member, 4...Cutting tool, 5.
...Holder, 6...Operation arm, 7...Motor, 8...Circular gear, 9...Fluid pressure cylinder, 10...Bead shape detector, 12...
- Bead shape measuring device, 13... Bead cutting shape setting device, 14... Arithmetic unit, 15... 11! i device.

Claims (1)

[Claims] A step of measuring the shape of the cut inner bead of the electric resistance welded steel pipe, a step of comparing and calculating the measured value of the measured inner bead shape with a predetermined set value, and a step of comparing the measured value of the inner bead shape with a preset value, A method for controlling the cutting position of an inner bead of an ERW steel pipe, comprising the steps of adjusting the cutting angle and height of a cutting tool based on the results.