SU991243A1 - Plant for testing material specimen for resistance against hot crack formation in welding - Google Patents

Description

The invention relates to a testing technique and can be used to test samples of materials for resistance to the formation of hot cracks in the development of welding conditions for various materials and the selection of materials for welded structures.

The installation of testing material samples for resistance to the formation of hot cracks during welding, which includes a welding device, a displacement actuator with clamps for fixing the welding specimen and a meter 3, is known.

Closest to the invention to the technical essence and the achieved result is an installation for testing samples of materials for resistance to hot cracking During welding, - containing a frame, a welding device mounted on it, a table with a drive for its rotation, a load cell and two grippers for fastening parts welded sample, one of which is placed on the table, and the other is rigidly fixed on the base 2J.

A common disadvantage of known installations is that they are not secured.

They produce sufficient test accuracy, since the tensile force is limited by the maximum torque value of the drive and is not constant along the length of the weld, because it depends on the distance to the weld point of the specimen from the axis of rotation of the table.

The purpose of the invention is to improve the accuracy of the test by ensuring that maximum tensile stresses are applied to the weld material along its entire length.

To achieve the specified goal

15 installation for testing specimens of materials for resistance against obrado-. hot cracks during welding, containing a frame, a welding device mounted on it, a table with

Claims (2)

20 by a rotation drive, a force meter and two grippers for - attaching parts of the sample to be welded, one of which is placed on the table, is equipped with a fixed, end switch, electrically connected to the table rotation drive, and a second lever fixed on the second gripper. the grip is pivotally fixed on the rack in such a way that the axis of the hinge is parallel to the axis of the first grip, and the lever interacts with the limit switch and the force meter, which is mounted on the rack. On . 1 shows the proposed installation, front view; Fig 2 is the same, side view. The installation contains a bed 1, mounted on a bed 1, a table 2 with a drive (not shown) of its rotation around the d-o axis, a rack 3 placed on the table 2 a gripper 4 whose axis t is perpendicular to the axis c - ot of the table rotation 2, the gripper 5, pivotally fixed on the table 3 in such a way that the hinge b-b axis is parallel to the c-axis of the gripper 4, limit switch b, electrically connected with the rotational drive of the table 2, the force meter 7 placed on the rack 3, and fixed on the gripper 5 lever 8 ,. interacting with a limit switch 6 and a force measuring device 7. In addition, the installation contains a welding device (not shown) mounted on the frame 1 with movement along the axis b-b. The installation works as follows. Part 9 of the test specimen is locked in the gripper 4, and part 10 is gripping 5 in such a way that their edges are located parallel to a given distance from each other. I start welding the parts 9 and 10 of the test specimen with a point, furthest from the axis a - from “turning the table 2, and at the same time turning the table 2 around the axis o - and at a given speed. The crystallized material of the weld in the weld plane undergoes tensile deformation at this expense due to the high speed relative to the movement of parts 9 and 10. A crack is formed in the weld with relatively small stretching forces. When moving the welding point towards the axis, the speed of mutual movement of the parts 9 and 10 of the sample decreases and the force required to form a crack in the weld increases. At some point, the formation of a hot crack ceases and the parts 9 and 10 of the specimen set. The force transferred from the table 2 and part 9 to the sample part 10 and the lever 8 increases to a predetermined value, and the force meter 7 is compressed, ensuring that the limit switch 6 is turned on and the table rotation drive 2 is turned off. Since the load cell 7 part 10 of the sample, the force on the force meter 7 does not depend on the speed of rotation of the table 2 and the distance from the welding point to the axis a –a, since the distance from the plane d - o) of welding to the axis b-b of the rotation of the lever B is always all the time The proposed installation allows testing materials samples for resistance to hot cracking during welding with a high degree of accuracy by ensuring a constant distance from the plane of the weld. to the axis of rotation of the lever, which transmits the force to the load cell, which allows maintaining the constant maximum efforts of the expansion of the weld material throughout its length. Claims. An installation for testing samples of materials for resistance to hot cracking during welding, comprising a frame, a welding device mounted on it, a table with its rotation drive, a load cell and two grippers for fastening parts of the sample to be welded, one of which is placed on the table below, characterized by that, in order to increase the test accuracy by ensuring the maximum tensile stresses of the material of the weld along its entire length, it is equipped with a stand-up, limit switch installed on the frame, ktricheski associated with rotation drive of the table, and attached to the second capture lever ,, the second gripper is fixed pivotally at the front obrazbm such that the hinge axis is parallel to the axis of the first grip, a lever cooperating with limit switch and siloyzmeritelem which is mounted on the rack. Sources of information taken into account in the examination of 1f USSR Author's Certificate No. 397810, cl. G 01 N 3/18, 1970. 2. USSR author's certificate No. 470734, cl. G 01 N 3/18, 1970 (prototype). 3 f