SU1419910A1 - Method of checking the quality of welded butt joints of plastic pipes - Google Patents

Abstract

The invention relates to the welding of thermoplastics, specifically to a method for controlling the quality of welded butt joints of plastic pipes. The purpose of the invention is to improve the quality of control. To achieve the goal, it was proposed to compare the geometrical dimensions of the base of the control sample 4 with the reference contours deposited on the transparent plate 5, which limit the permissible deviations of the controlled geometrical dimensions. The control sample 4 is cut out from the outer burr 3 in such a way that the cutting plane is a tangent plane to the outer surface of the welded pipes 1 and 2. The proposed method allows to obtain information on all the most important geometrical characteristics of the butt joints of plastic pipes, including the length of the fusion line and the value base grata, not causing damage to the welded joint. The configuration of the control sample allows to judge the degree of misalignment of the pipes being welded and the degree of curvature of the external surface of the burr. The use of standardization in the implementation of control allows you to quickly and without significant effort to obtain information about the quality of the weld, 3 sludge. % (L

Description

with

FIG. 3

The invention relates to the welding of plastics, and more specifically to the welding of plastic pipes with a hot tool using a butt weld,

The purpose of the invention is to improve the quality of control.

FIG. 1 shows a welded butt seam, a cross section; na fig, 2 bases ania of the control sample; on D), 3 -. Scheme of implementation of the method. The proposed method is implemented in a manner that, I, when controlling the quality of the welded butt joint of pipe 1 with pipe

3 of the external grata 2 along the plane | C, which is tangent to the sensible surface of the pipes being welded, the control sample 4 is cut. Then the control sample 4 is applied onto the transparent plates tty 5, with the reference contours previously bounding The tsute of the permissible outline of the bases of the control samples. If the base of the test specimen is completely interfacial between the circuits, the welded joint is considered fit. If, on the other hand, the control specimens go beyond the specified limits, then the welded soybean is considered defective; Admissible deviations of the base configuration of the control specimen limited by reference contours are established experimentally,

The width of the outer flash b and the size of the base of the outer bur is measured directly on the control sample, and the height of the outer burr h 40 and the length of the fusion line f are determined from the relationships:

 b.,

(2)

the length of the control sample;

nominal outer diameter and wall thickness of the welded pipes ;,

- uchasch.stki lines of fusion, coming respectively on the outer and inner grates.

Because

i

- t

| 5D

and

about

f. .sG

(3)

In addition, the base configuration of the control sample allows judging of such characteristics of butt joints as the degree of misalignment of the pipes being welded and the degree of curvature of the external surface of the burrs.

This method has the following advantages.

The quality control of welded butt joints is carried out by comparing the geometric dimensions of the base of the test specimen with the reference contours limiting the minimum and maximum allowable outlines and, which allows to obtain information on all the most important geometrical characteristics of the butt joints, including the length of the fusion line and the size of the base. Grata, no damage to the welded joint. The base configuration of the control sample also makes it possible to judge the degree of misalignment of the pipes being welded and the degree of curvature of the external surface of the burr. .

The use of standardization in the implementation of control allows you to quickly and without significant effort to obtain information about the quality of the weld. A control sample or a photograph of its base, combined with the reference contours, can serve as a document with more evidence of the results of the control carried out. The presence of a cut on the outer edge of the joint and the corresponding mark indicates that this welded joint has already been subjected to a quality check, as well as a document where the results of such a check are recorded.

These advantages provide high reliability of control results.

Claims (1)

Invention Formula The method of quality control of welded butt joints of plastic pipes, by measuring the geometrical dimensions of the outer flash, characterized in that, in order to improve the quality of control, a control sample is cut out of the outer flash, the cut-off plane of which is a tangent plane to the outer cylindrical surface of the welded pipes, and matching are configuration-based day of the test sample Phie. 7 Editor L. Veselovska Compiled by I. Frolova Tekred L. Oliinyk Order 4280/19 Circulation 559 VNISh State Committee of the USSR for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 with reference contours limiting its tolerances by overlapping the contour of the base of the control. on reference contours. Thebes.2 Corrector MCHaroshi Subscription