JP3130550U - Weld spot shear test jig and weld spot shear test equipment - Google Patents

Abstract

Provided are a test jig and a test apparatus for conducting a welding point shear test by omitting grinding of burrs and sags adhering to a cross-shaped test piece.
An axial longitudinal groove 11 into which a long steel bar 21 of a cross-shaped test piece 2 is fitted into a round bar-shaped metal member having sufficient strength to withstand a welding point shear test, and the long steel bar 21 A transverse groove 12 into which a short steel bar 22 welded orthogonally to the longitudinal groove 11 is fitted, and a flat connecting portion 13 on the closed side of the longitudinal groove 11 for gripping with a gripping tool attached to a tensile testing machine. Form. A circular hole 14 is formed in the closed end of the longitudinal groove 11 so that the end of the long steel bar 21 produced when the cross-shaped test piece 2 is collected can be fitted with the sag 2b or burr 2c attached.
[Selection] Figure 2

Description

  The present invention relates to a weld spot shear test jig and a weld spot shear test apparatus, and more particularly, to a test jig and a test apparatus for testing a weld wire mesh and a reinforcing bar lattice weld spot shear strength.

  Conventionally, when testing the shear strength of welding points such as a welded wire mesh and reinforcing bar grid in which iron wires and steel bars are superposed in a grid shape and welded at the intersection, as shown in FIG. A cross-shaped test piece 2 including a welded portion 2a is taken, and a long steel bar 21 and a short steel bar 22 perpendicular to the long steel bar 21 of the cross-shaped test piece 2 are formed into a longitudinal groove 42 and a lateral direction as shown in FIG. With the groove 43 formed in the test jig 4 formed, the connecting portion 41 of the test jig 4 and one end of the long steel bar 21 are pulled with a tensile tester, and the welded portion 2a can endure until it is sheared. A value obtained by dividing the maximum load by the original cross-sectional area of the long steel bar 21 is measured as the welding point shear strength (Non-Patent Document 1).

  Since the test jig 4 minimizes the deviation of the central axis with respect to the tensile direction of the cross-shaped test piece 2, the groove width of the longitudinal groove 42 formed in the test jig 4 is the long steel bar of the cross-shaped test piece 2. It is suppressed to such an extent that a minute gap of about 0.2 mm is obtained with respect to the maximum width of 21.

  Sampling of the cross-shaped test piece 2 from a welded wire mesh and a reinforcing bar grid is mainly performed using a tool such as a shear or a saw. For example, when cutting with a shear, the cutting direction is as shown in FIG. The sag 2b tends to remain, and when cutting with a saw, the burr 2c tends to remain around the cut end as shown in FIG. 9B.

The sagging 2b and burrs 2c as described above remain in all the cut portions of the long steel bar 21 and the short steel bar 22 of the cross-shaped test piece 2, but one end of the long steel bar 21 is particularly at the end of the test as shown in FIG. Since it is stored in the longitudinal groove 42 of the jig 4, when the sag 2 b or burr 2 c is generated at the end thereof, the long steel bar 21 does not fit smoothly into the longitudinal groove 42 due to contact with them, or it is forced to fit. The long steel bar 21 is inclined. For this reason, the work of removing the sagging 2b and the burr 2c by grinding the vicinity of the cut-out opening of the cross-shaped test piece 2 with a simple grinder such as a grinder as required.
JIS G3551: 2000

Since the conventional welding point shear test jig is configured as described above, even if slight burrs or sagging occurs at the end of the cross-shaped test piece 2, extra work is required to scrape it off. When many samples were tested, it was difficult to smoothly perform the shear strength test, and much test time was spent.
The present invention has been made in view of such circumstances, and it is possible to perform a welding shear strength test without grinding even if burrs or sagging occur at the end of the cross-shaped test piece 2. An object of the present invention is to provide a welding point shear test jig and a welding point shear test apparatus.

In order to achieve the above object, the welding point shear test jig of the present invention is a test jig in which a cross-shaped test piece cut from a wire mesh or lattice welded with a steel bar is fitted and a shear load is applied to the welded portion. A longitudinal groove into which the long steel bar of the cross-shaped test piece can be inserted and a horizontal groove into which the short steel bar of the cross-shaped test piece can be inserted are formed. A part or all up to is formed larger than the groove width, and a connecting part for connecting to the grip part of the material testing machine is provided on the side opposite to the other end where the longitudinal groove is opened. is there.
A welding point shear strength test apparatus according to the present invention includes a welding point shear test jig, a first gripping part that grips the connecting part of the jig, and the jig of the cross-shaped test piece inserted into the jig. A load mechanism for holding a portion that protrudes from the longitudinal groove; and a load mechanism for applying a tensile test force to the cross test piece by separating the two grip portions from each other; and A measuring mechanism for measuring the test force is provided.

  The jig for welding point shear test and the welding point shear test apparatus of the present invention are configured as described above, and even if burrs and sags generated on the test piece remain, these are formed in a portion where the longitudinal groove is formed largely. There is no need to remove it.

  By using the welding point shear test jig and welding point shear test device of the present invention, unnecessary grinding work such as burrs and sag required for conventional test pieces becomes unnecessary, and smooth test work is possible. Become. As a result, the test piece can be manufactured without depending on the test piece cutting method.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a plan view (A), a right side view (B) and a left side view (C) of a welding point shear test jig (hereinafter referred to as a test jig) 1 of the present invention, and FIG. 2 is a cross-shaped test piece. 2 is a plan view (A) of the test jig 1 in a state where 2 is fitted, and an enlarged view (B) of the portion A. FIG.

  As shown in FIGS. 1 and 2, the test jig 1 is a shaft in which a long steel bar 21 of a cross-shaped test piece 2 is fitted in a round bar-shaped metal member having sufficient strength to withstand a welding point shear strength test. A longitudinal groove 11 in a direction, a lateral groove 12 into which a short steel bar 22 welded orthogonal to the long steel bar 21 is fitted, and a gripping tool attached to a tensile testing machine at the right end. Further, a sag 2b and a burr 2c at the end of the long steel bar 21 generated when the cross-shaped test piece 2 which is a feature of the present invention is collected are formed in the inner part of the longitudinal groove 11 at the back of the longitudinal groove 11. A circular hole 14 having a diameter larger and deeper than the groove width of the longitudinal groove 11 is formed to enable fitting without contact.

  As shown in FIG. 2, the cross-shaped test piece 2 is pulled by holding the connecting portion 13 and the protruding portion 21a of the long steel bar 21 with a gripping tool of a tensile tester while being fitted in the test jig 1. Then, a welding point shearing force test is performed by applying a shearing force, and a value obtained by dividing the maximum load endured until shearing by the original cross-sectional area of the long steel bar 21 is measured as the welding point shearing strength.

  In this case, the tensile force of the tensile testing machine acts on the protruding portion 21 a of the long steel bar 21 and the left side surface of the short steel bar 22, and the long steel bar 21 along the lateral groove 12 and the longitudinal groove 11 on the left side thereof. The short steel bar 22 is fitted without any trouble and the orthogonality is maintained, so that the long steel bar 21 is inclined by increasing the gap between the lateral groove 12 and the right longitudinal groove 11 and the long steel bar 21. Even if it occurs, the effect of the tensile force on this part does not affect the weld shear strength, and an accurate weld shear strength can be measured.

  FIG. 3 shows a test jig 1A which is a modification of the test jig 1. This test jig 1A has a longitudinal direction in order to accommodate a burr and a sag near the end of the long steel bar 21 generated when the cross-shaped test piece 2 which is a feature of the present invention is collected at the back side of the longitudinal groove 11. An enlarged groove 15 having a groove width wider than that of the direction groove 11 is formed. By using this test jig 1A, even if the dimensions of the long steel bar 21 of the cross-shaped test piece 2 vary, the burrs and sag of the terminal are accommodated in the enlarged groove 15, and the central axis of the long steel bar 21 A shear load is applied in a state where there is no deviation.

  FIG. 4 shows a test jig 1B which is another modification of the test jig 1. This test jig 1B is provided with an enlarged groove 16 having a groove width larger than that of the longitudinal groove 11 in the back direction from the lateral groove 12 and deeper. As a result, even if there is a large variation in the dimension of the front and rear long steel bars 21 from the short steel bar 22 of the cross-shaped test piece 2, burrs and sags generated in the long steel bar 21 can be accommodated in the enlarged groove 16 and the shear test can be performed. it can.

  The configuration of the welding point shear test apparatus 3 according to the present invention is shown in FIG. The welding point shear strength test apparatus of the present invention includes any one of the test jigs 1, 1 </ b> A, 1 </ b> B, a pair of grips 31, 31 for gripping them, and a machine base D on which one of the grips 31 is fixed. The cross head 33 is mounted with a load sensor 32 for detecting the load while connecting and moving the other, and a pair of screw rods 34A and 34B for driving the cross head 33 by screwing, and the motor M and gear coupling. The measurement control device 36 mainly composed of a microcomputer for measuring the welding point shear strength of the cruciform test piece 2 by controlling the drive mechanism 35 for rotationally driving the screw rods 34A and 34B and the entire device by measuring the tensile load. It is composed of

  The gripping tool 31 has a pair of gripping teeth 31a for holding the long steel bar 21 of the cross-shaped test piece 2 or the connecting portion 13 of the test jig 1 in close proximity to each other as shown in FIG. 31a, a shaft 31e integrated with a pressure receiving plate 31d sealed with an O-ring 31c that advances and retracts this gripping tooth 31a along an inclined surface in the guide 31b, the force of the spring 31f, and the hydraulic pressure transmitted through the port 31g The cylinder 31h moves the shaft 31e linearly according to the difference, the holder 31j and the mounting base 31k for moving the gripping teeth 31a and the shaft 31e in a movable manner.

  In order to perform a test using the above-described welding point shear test apparatus, a cross-shaped test piece 2 is accommodated in a test jig 1 as shown in FIG. 2, and a long steel bar 21 is held by a grip 31 on the machine base D side. After gripping, the connecting portion 13 of the test jig 1 is gripped by the grip 31 on the cross head 33 side. A shear load is applied to the welded portion 2a by the shear test program of the measurement control device 36, the load value is measured, and converted to shear strength. The present invention is not limited to the above-described embodiments. For example, hydraulic pressure or air pressure can be used as a drive source of the shaft 31e.

  The welding point shear test jig and the welding point shear test apparatus of the present invention are particularly used as a test jig and a testing apparatus for welded wire mesh and reinforcing bar lattice welding point shear tests.

It is the top view (A) of the jig 1 for a test by the Example of this invention, its right view (B), and left view (C). They are a top view (A) in the state where the cross-shaped test piece 2 was accommodated in the test jig 1 of the present invention, and an enlarged view (B) of the portion A. It is a top view of 1 J of test jigs by a modification. It is a top view of the test jig 1B by another modification. It is a block diagram of the welding point shear test apparatus 3 of this invention. It is a partial cross section block diagram of the holding tool 31 concerning an Example. It is the top view (A) of the cross-shaped test piece 2, and its side view (B). It is a perspective view of the conventional jig for a welding point shear test. It is the top view and side view of each of the cross-shaped test piece (A) which produced the sagging, and the test piece (B) which produced the burr | flash.

Explanation of symbols

1 Welding point shear test jig (test jig)
DESCRIPTION OF SYMBOLS 11 Longitudinal groove 12 Lateral groove 13 Connection part 14 Circular hole 15 Enlarged groove 16 Enlarged groove 2 Cross-shaped test piece 2a Welded part 2b Burr 2c Burr 21 Long bar steel 21a Protruding part 22 Short bar steel 3 Welding point shear test device 31 Grasp Tool 31a Grasp 31b Guide 31c O-ring 31d Pressure receiving plate 31e Shaft 31f Spring 31g Port 31h Cylinder 31j Holder 31k Mounting base 32 Load sensor 33 Crosshead 34A Screw rod 34B Screw rod 35 Drive mechanism 36 Measurement control device 4 Test jig 41 Part 42 Longitudinal groove 43 Lateral groove D Machine base M Motor

Claims (2)

A test jig for fitting a cross-shaped specimen cut from a wire mesh or grid welded with steel bars and applying a shear load to the welded portion, and a longitudinal groove into which the long steel bars of the cross-shaped specimen can be inserted And a transverse groove into which the short steel bar of the cross-shaped test piece can be inserted is formed, and a part or all of the longitudinal groove from the transverse groove to the back end is formed larger than the groove width, and the longitudinal direction. A jig for welding point shear test, characterized in that a connecting portion for connecting to a gripping portion of a material testing machine is provided on the side opposite to the other end where the groove is opened. A welding point shear test jig according to claim 1, a first grip part for gripping the joint part of the jig, and a cross-shaped test piece inserted into the jig projecting from a longitudinal groove of the jig. A load mechanism for applying a tensile test force to the cross test piece by separating the two grip portions from each other and a measurement for measuring the test force when a load is applied A welding point shear test apparatus characterized by comprising a mechanism.

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