The national standard of floor spring door is that the first-class product is opened ≥ 300000 times (actually the minimum standard of qualified products), the high-quality product is opened ≥ 500000 times, and the European standard is the minimum 500000 times. Therefore, the selected floor spring must reach 500000 times. 500000 times are not random. They need to be tested. Usually, manufacturers have test reports, which are usually stamped with the chapters of Ma and CNAL. These two chapters can only be covered by national recognized laboratories. Only by recognizing these data can they be true.
