High-strength bolts are bolts made of high-strength steel, usually used in the connection of Bridges, railways, wind power, rail, high-pressure equipment, these are large-scale engineering projects or equipment, high-strength bolts play a very important role in them. Generally used for connection, it is strictly prohibited to reuse, and it can be put into use after passing the test. High strength bolts and their connectors are often tested as follows :
1. Mechanical properties of high-strength bolts: tensile test, wedge load test, impact test, tensile load test, core hardness test, decarburization test to measure. The test indexes are tensile strength, specified non-proportional extension strength, elongation after breaking, shrinkage after breaking, impact absorption work, tensile load, Vickers hardness, Rockwell hardness, decarburization layer, etc.
2. Nut mechanical performance test: ensure load, Rockwell hardness, Vickers hardness, washer hardness.
3. Connection pair of high-strength bolts: torque coefficient, screw thread of bolts and nuts, screw thread end of bolts, surface defects, size and shape tolerance, surface treatment, etc.
4. Bolt, nut, washer performance rating and material composition analysis: detection of carbon, manganese, silicon, phosphorus, sulfur, vanadium, boron, copper and other elements. Detection range:
Shear type high-strength bolt, hexagon head high-strength bolt, wind power high-strength bolt, steel structure high-strength bolt, bridge high-strength bolt, friction type high-strength bolt, high-strength anchor bolt
Test item:
Tensile strength, guaranteed load, torque coefficient, elongation after breaking, shrinkage after breaking, impact absorption work, tensile load, Vickers hardness, Rockwell hardness, decarburization layer, etc.