Dongguan tensile testing machine fixture features

Dongguan tensile testing machine fixture features

Haida Detection Instrument Co., Ltd. is a professional tensile testing machine manufacturer in Dongguan. The tensile testing machine produced by this company has a complete product range and excellent quality. Haida today analyzes the knowledge of the fixture, which is an indispensable part of the tensile testing machine. Many people ask about fixtures. Today we talk about the type and function of fixtures.

According to different test methods, fixtures can be roughly divided into: tensile fixtures, compression fixtures, bending fixtures, peeling fixtures, and shear fixtures, among which the tensile fixtures account for about 80 % of the fixtures.

  Dongguan tensile testing machine fixture features

a . We know that by clamping the specimen ( or product ) with the fixture to apply force to the specimen, the size of the test force that the fixture can withstand is a very important indicator of the fixture. It determines the size of the jig structure and the labor intensity of the jig operation. The sample material is divided into metal and non-metal, and the shape has the size of the size. The composition of the materials is various. The test force that the sample can withstand is as small as tens of centimeters ( such as spandex filaments for textiles ) and as large as tens of tons ( such as ordinary steel materials; the largest electronic universal testing machine in China). The test force is 600KN, class 0.5 ) , the sample size is as small as 0.006mm diameter gold wire, and as large as 1m diameter PVC pipe. This requires the design of different fixtures based on different test forces and sample size.

b . Dongguan tensile testing machine requirements for fixture materials:

â‘ . For general metal and non-metallic specimen, the clamp jaws direct contact with the sample, generally high quality alloy steel, high alloy steel (low carbon or alloy steel), cold work tool steel and the like, by an appropriate The heat treatment process ( quenching and tempering, carburizing and quenching, etc. ) increases its strength and wear resistance . Sometimes it also inserts special steel at the jaws , or sprays gold sand on the jaw surface .

â‘¡. Some small force test fixture surface in contact with the sample using a soft rubber adhesive and the like. ( Example: Fixture clamping surface of plastic film, filament, etc. )

3Clamps are generally made of high quality medium carbon steel and alloy structural steel, and their mechanical properties are increased through proper heat treatment process. Sometimes non-ferrous metals such as aluminum alloys and special metals are used to reduce weight. Casting structures ( cast steel , cast aluminum, etc. ) are sometimes used

c . Dongguan tensile testing machine on the fixture structure requirements:

â‘ . According to the test fixture designed primarily sample and standard materials (especially semi-finished products and finished products) of shape and material. The above-mentioned test standards refer to ISO , ASTM , DIN , GB , BS , JIS , etc., as well as enterprise standards, industry standards, etc. These standards generally have strict regulations for sample preparation and test methods. We can design different fixtures based on different specimens and test methods. For fixtures used for special specimens ( finished and semi-finished products ) , fixtures are mainly designed based on the shape and material of the specimen.

â‘¡. Clamp does not have a fixed structure (e.g., a wire can be clamped winding method may also be used two clamping plates, sheet metal clamping wedge can be a sample, may also be employed to clamp a clamping manner), which There is a clear difference from the host. Hosts are much the same at home and abroad, and fixtures are different from domestic ones and domestic ones. There are also big differences between different companies. This mainly depends on the overall level of the company and the accumulated experience of designers. Fixtures from foreign countries, such as INSTRON , MTS , ZWICK, etc., are generally meticulous in workmanship, availability is high, but prices are higher, and they are in the high-end market; while our fixtures have a large market share in the domestic market, To some extent, it can replace some of the fixtures in foreign countries, in the high-end market. However, there are still some gaps between domestic and foreign standards in the use of fixtures for new materials and special materials.

U.S. TestResources Mechanical Testing System All-electric Servo Static Pulling, Pressing, Torsional Testing Machine, Dynamic & Fatigue Series Testing Machine, with various professional fixtures, also used for other brand testing machines

3 . Dongguan tensile testing machine fixture itself is a locking mechanism, we know that the mechanical locking structure: 缧 lines ( ie thread, screws, nuts ) , bevels, eccentrics, levers, etc., the fixture is a combination of these structures. There is no fixed pattern for the fixture of the testing machine . According to the different specimens and the test force size , there is a great difference in the structure . ( The test specimen with large test force generally adopts the inclined clamping structure , with the increase of the test force , the clamp With the increase of tightness, the shoulder sample adopts suspension structure, etc. ) . If the fixture is divided by structure, it can be divided into wedge-shaped fixtures ( referring to fixtures with inclined locking principle ) and clip-type fixtures ( single-sided or tightening clamp structure principle duplex crest), twining clamp (specimen locking means by way of winding jig), refers to the use OFFSET jig (jig eccentric locking principle structure), a lever type clamp (refers to the use of the lever force (Amplification of the principle of the structure of the fixture ) , shoulder type fixture ( refers to the shoulder specimen of the fixture ) , bolt type fixture ( refers to the bolt, screw, stud and other test thread strength fixture ) , 90 ° peel type fixture ( Refers to fixtures that are suitable for vertical and double peeling of two specimens ) . Each of these fixtures has its own advantages and disadvantages. For example, a wedge-shaped fixture has a small initial clamping force and increases with the test force. The clamping force increases. For clip fixtures, the initial clamping force is large and increases with the test force. The clamping force decreases.