Analysis of special requirements of universal testing machine fixture

The special characteristics of the universal testing machine fixture for material characteristics and applicable environment:

There are several types of special materials that are limited, and the tensile tester fixtures do not fully satisfy them.

A, steel wire, steel strands, such as high hardness test, loose internal structure, uneven force during stretching, the jaws of the fixture are subject to wear and tear, so that the long-term work of the furniture jaws will shorten the life.

B. When the material with large deformation is clamped, the clamp clamping method is required.

C. The requirements of the high and low temperature tensile testing machine fixtures are particularly large, and must meet the requirements of small volume, high hardness, high temperature resistance and low temperature.

D. If the test sample has a high frequency, the domestic fixture is not automated, and it will be a burden to the tester.

E. Testing the finished product or the finished product sample requires the manufacturer to customize the fixture. This difficulty is a bit large.

F. Holding the aluminum foil for testing, even if the tensile testing machine clamp using the sprayed diamond is solved compared with the traditional slipping problem, the fracture position is always unsatisfactory. The 10 samples can only be about half successful, and the waste is still quite a lot. .

Universal testing machine fixtures should meet material and structural requirements:

The material requirements of the tensile testing machine fixture can be summarized as the wear resistance of the fixture, high hardness, high temperature resistance and convenient clamping.

A. Holding some small specimens requires a rubber protective sleeve at both ends of the jaws, which is convenient for clamping.

B. The main metal parts of the fixture are made of high-quality medium-carbon steel and alloy structural steel, and their hardness and wear resistance are improved by appropriate heat treatment process. Sometimes some aluminum alloy and carbon alloy are added to reduce the weight of the fixture.

C, the fixture should use high-quality alloy structural steel, alloy high carbon steel (or low carbon alloy steel), cold work die steel, etc., through the appropriate heat treatment process (quenching tempering, carburizing quenching, etc.) to increase its strength, wear resistance . Special fixtures will spray gold steel sand in the jaws to match the aluminum foil

Universal testing machine fixture structure requirements:

1. The design of the test fixture structure is mainly based on the test standards of the materials and the shapes and materials of the samples (specifically, finished and semi-finished products). Common specimens can be tested using universal fixtures according to the standard. Special specimens need to be customized according to the shape and size of the specimen. The principle is to facilitate the clamping.

2. The design of the test machine fixture structure is not fixed. The core of the design is to facilitate the clamping of the sample. Wire clamping does cause wear on the fixture. At present, the domestic fixture manufacturing is OK. Unless you do frequent tests, you don't need to use automatic fixtures. You can customize foreign automatic fixtures according to the situation. We are currently studying in this area.

Jiangsu Tianhui Testing Machinery Co., Ltd. is a professional service manufacturer engaged in material testing and testing equipment. It integrates R&D, design, production, sales and service, and provides solutions for material testing and finished product testing.