Fifthly, when selecting ball valve products, we should also pay attention to the production time of the products. Generally speaking, there is no such problem as warranty period for such products. But from the perspective of production process development, the fresher the production year, the better the process and quality of the products. 　　

Therefore, appropriate materials should be selected to prolong the service life of gate valves. For others, it is necessary to consider the impact of high temperature time limit on material process performance, such as changes in flexibility and stress corrosion. When the temperature reaches the standard or exceeds the quenching temperature, the valve internals will cause quenching, tensile strength reduction and other problems. In order to avoid the change of material tensile strength, the maximum temperature limit must be selected within a safe range.