Introduction to the analysis and introduction of hydraulic universal testing machine fixture

The fixture isHydraulic universal testing machineAn indispensable part. According to different test methods, fixtures can be roughly divided into: tensile fixtures, compression fixtures, bending fixtures, peel fixtures, shear fixtures, etc. Among them, tensile fixtures account for about 80% of the total fixtures.
one. Requirements for fixture materials of hydraulic universal testing machines:
①. For general metal and non-metallic specimens, the jaws of the fixture are in direct contact with the specimens. Generally, high-quality alloy structural steel, alloy high-carbon steel (or low-carbon alloy steel), cold-work mold steel, etc. are used to increase their strength and wear resistance through appropriate heat treatment processes (quenching, carburizing and quenching, etc.). Sometimes special steel is also installed at the jaws, or gold steel sand is sprayed on the surface of the jaws.
②. For some fixtures with small test force, the surface in which they come into contact with the sample is used to use soft rubber. (For example: the clamping surface of plastic film, fiber wire and other samples.)
③ The specific clamping is generally made of high-quality medium-carbon steel and alloy structural steel, and its mechanical properties are increased through appropriate heat treatment processes. Sometimes, non-ferrous metals such as aluminum alloys and special metals are used in order to reduce weight. Sometimes cast structures (cast steel, cast aluminum, etc.)
two. We know that by clamping the sample (or product) by clamping the sample, the amount of test force that the clamp can withstand is a very important indicator of the clamp. It determines the size of the fixture structure and the labor intensity of the fixture operation. The sample materials can be divided into metal and non-metallic, and the shapes can be divided into size. The composition of the materials is various. The test force that the sample can withstand is as small as a few dozen centimeters (such as spandex wire for textiles), to dozens of tons (such as ordinary steel, etc.; the domestic electronic hydraulic universal testing machine test force is 600KN, 0.5-level machine), the sample size is as small as gold wire with a diameter of φ0.006mm, and to PVC pipe with a diameter of 1m. This requires the selection and design of different fixtures according to different test forces and the shape and size of the sample.