JPS6161617B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for bending a test piece for bending tests of welded joints.

Among the mechanical tests of welded joints using test pieces, regarding bending tests, the Japanese Industrial Standards include JIS Z 3122 "Type bending test method for butt welded joints", JIS Z 3123 "Free bending test method for butt welded joints", There are JIS Z 3124 ``Roller bending test methods for butt welded joints,'' but they all relate to butt welding, and there are no regulations regarding fillet welded joints as shown in Figure 1. (1st
In the figure, t indicates a test piece and f indicates a fillet weld. ) Also, JUS Z 3155 has a method for back-bending fillet welded joints, but this is difficult to apply to the fillet welded joints shown in Figure 1.

Therefore, in order to perform a bending test on the fillet welded joint shown in FIG. 1, it is conceivable to use a method similar to the wrapping method among the methods shown in JIS Z 2248 "Metallic material bending test method". Figure 2 illustrates the above JIS Z 2248 method, in which the test piece t is placed on the winding die d and wrapped around the die head (test piece winding part) having a predetermined radius r. This shows the state in which a bending test is performed. (b is the stand.) However, if we try to apply the above method to the test piece shown in Figure 1, as shown in Figure 3,
In test piece t, since the part near the head of the winding die d was made of two layers, the part of the base material away from the head of the die was bent, not the welded part.
This was not appropriate as a bending test for welded parts, and improvements were desired. (In Fig. 3, t is the test piece before being bent, f is the fillet weld joint, d is the wrapping die, r is the radius of the arc of the die head, t' is the test piece after being bent, and b is the stand. The object of the present invention is to solve the problems encountered when applying the above-mentioned conventional winding method, and to provide an appropriate method of bending a fillet weld joint and an apparatus therefor.

The method for bending a test piece of the present invention includes, in a bending test of a test piece having a fillet welded joint by the wrapping method, a winding portion of the test piece whose cross section forms a predetermined arc at one end of the winding die. Attach the test piece to a winding mold so that the joint part is located, and while holding down the double layered part of the test piece connected to the joint with a roller, turn the roller around the center line of the arc of the test piece winding part as the pivot axis. This method is characterized by winding the test piece around a winding mold. Further, a test piece bending device for carrying out the method of the present invention includes a substrate having a test piece wrapping portion whose cross section at one end forms a predetermined arc, and a substrate sandwiching the test piece wrapping portion. A pair of levers attached to the base plate so as to be able to rotate about the center line of the circular arc, a connecting member that connects the tops of the pair of levers to each other to form a gate shape, and a space between the levers of the gate shape. and a test piece holding roller attached parallel to the rotation axis. DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the test piece bending method and apparatus of the present invention will be explained below with reference to embodiment figures.

FIG. 4a is an explanatory diagram (side view) of the method of bending a test piece according to the present invention. In the figure, reference numeral 1 denotes a substrate that serves as a winding die in the winding method, and one end thereof forms a test piece winding section 2 whose longitudinal section forms a predetermined circular arc. t is a test piece fixed to the substrate 1 with bolts 3 or the like so that the fillet weld joint f is located at the test piece wrapping portion. 4 is attached to the lever 5 in parallel to the center line of the test piece wrapping part, with a turning radius l determined so as to be in contact with the upper surface of the two-ply part connected to the fillet weld joint part of the test piece t. It's a roller. The levers 5 are a pair of levers fixed to each other across the test piece wrapping portion 2 of the substrate 1, and are gate-shaped, and rotate the roller 4 with the center line of the test piece wrapping portion of the substrate as a pivot axis. be able to.

As shown above, when the lever is turned in the direction of the arrow in the figure while holding down the two-ply part connected to the joint of the test piece attached to the board (wrapping type) with the roller, the test piece will be wrapped around the test piece wrapping part. It is effective as a bending test for joints because it is bent around the weld.
In addition, in order to make the bending work easier (to save the bending force F), you are free to use a long lever to extend the length of the lever to L, or to add an auxiliary lever. be. According to the method of the present invention, due to the effect of the roller that rotates while holding down the test piece, the test piece does not bend from a position away from the weld joint as in the case of the conventional wrapping method, and the weld part bending evaluation becomes possible.

FIG. 4b is a perspective view of an apparatus for carrying out the test piece bending method of the present invention. In the figure, 1 is a board of the bending test device made using a strong material such as a steel plate (acts as a wrapping mold), and 2 is a test piece having a predetermined arc cross section at one end of the board. Department. Reference numeral 5 denotes a pair of levers which can be rotated about the center line of the circular arc as a pivot axis, sandwiching the test piece winding portion, and are fixed to each other by a connecting member 6 at their tops to form a gate shape. In order to firmly attach the lever, it is also possible to make only the side edges of the board thicker than the other parts. Connecting member 6
may be used in plural pieces to strengthen the lever, or may be in the form of a long plate. The length of the lever can be increased by attaching an auxiliary lever (not shown) for addition. 4 is attached to the gate-shaped lever in parallel to its pivot axis,
This is a test piece holding roller that rotates as the lever turns, and is installed with a turning radius l determined so that the lower surface of the roller holds down the two-ply part connected to the welded joint of the test piece attached to the board. 7 is a bolt hole for fixing the test piece to the board.

Attach a test piece to the device as described above (t in the figure indicates the test piece, f indicates the fillet weld joint), and test using the roller 4 by rotating the lever 5 in the direction of the arrow. The bending test can be effectively performed by wrapping the test piece around the joint part around the test piece winding part 2 of the board 1 while holding the piece.

[Brief explanation of the drawing]

Figure 1 is a side view of a fillet weld joint, Figure 2 is a JIS
An explanatory diagram of the winding method of Z 2248, Fig. 3 is an explanatory diagram to show the difficulties when applying the winding method to fillet welded joints, and Fig. 4a is an explanatory diagram of the bending method of the test piece of the present invention. Figure 4b is a perspective view of an apparatus for carrying out the method of figure a. t, t'...test piece, f...fillet weld joint, d...wrap type, b...stand, 1...board, 2
...Test piece wrapping part, 3...Bolt, 4...
...Roller, 5...Lever, 6...Connecting member, 7
...Bolt hole.

Claims (1)

[Claims] 1. In a bending test of a test piece having a fillet weld joint by the wrapping method, a joint part is attached to the winding part of the test piece whose cross section forms a predetermined circular arc at one end of the winding mold. Attach the test piece to a winding mold so that the test piece is in the same position, and while holding down the double layered part of the test piece connected to the joint with a roller, rotate the roller around the center line of the circular arc of the test piece winding part as the rotation axis, and perform the test. A test piece bending method characterized by wrapping the piece around a winding die. 2. A board having a test piece winding part whose cross section forms a predetermined arc at one end, and a board mounted to the board so as to be able to rotate around the center line of the arc across the test piece winding part. A pair of levers, a connecting member that connects the tops of the pair of levers to form a gate shape, and a test piece holding roller installed parallel to the pivot axis between the gate-shaped levers. A test piece bending device.