Quality inspection standards for SKL fastener systems

The quality inspection of SKL fastener system runs through the whole life cycle from raw material procurement to finished product delivery. In the process of raw material storage, chemical composition analysis and mechanical property testing are strictly implemented. The chemical composition of steel is tested by spectrometer to ensure that the content of elements such as carbon, silicon, and manganese meets the standard requirements; through tensile tests, impact tests, etc., the tensile strength, yield strength, impact toughness and other indicators of the material are measured. Only raw materials that meet the standards can enter the production process. ​

In the production process, automatic testing equipment is used for real-time monitoring. For example, a high-precision image measuring instrument is used to detect the dimensional accuracy of the components, and the key dimensional errors such as the opening size of the tension clamp and the thread parameters of the screw spikes are controlled within a very small range; through non-destructive testing technologies such as eddy current flaw detection and magnetic particle flaw detection, the internal defects of the components are screened to eliminate cracks, sand holes and other problems. In the finished product stage, comprehensive performance testing is carried out. The tensile fatigue test simulates the stress conditions of the train under long-term operation to verify the fatigue life of the components; the salt spray test evaluates the corrosion resistance of the anti-corrosion coating; the aging test simulates different ambient temperature and humidity conditions to test the stability of the material in extreme environments. Only products that have passed all rigorous tests can be labeled as qualified, ensuring that every SKL fastener system can meet the high standards of engineering construction.