The quality of "Shangcheng" products has the following technics points:
1. To use the high grade alloy steel, carbon steel as raw material, from the composition analysis, spectroscopic analysis, mechanical property test and spark discrimination detecting, completely avoid the raw material mixture, and keep the material using according to GB Standard requirement.
2. The production of bolts uses advanced high efficiency Z47-24/4 multiposition automatic cold forming lathe, guarantee the sizes, according to GB Standard.
3. Adopting the computerized Numerical Control Technique to machine the breakage groove of torshear type bolts can improve the machining precision of groove, guarantee the assembled quality.
4. After heat treatment the bolts will 100% be sorted by hardness no-defeat detection according to company internal control regulations, to prevent the material mixture and products crack, guarantee 100% ok in mechanical properties.
5. The torsion coefficient of bolting is tested with the intelligentized axial force tester and high precision torque spanner, to guarantee the data result veracious and reliable
6. Bolting mechanical properties are tested by the tensile strength tester, impact tester and hardness testers, to guarantee the detect precision.
7. The strict assurance methods are carried out in the corrosion-resistant processes, bolting torsion coefficient control processes.