Regarding the design of cut-off valves

The installation of isolation valves is generally determined based on the process flow and equipment protection requirements. In chemical plants, the isolation valves located before and after pumps are used to isolate and control fluids, thereby preventing mutual interference and protecting the equipment and pipelines. Moreover, during the stopping, starting, and regulating of the pump, the shut-off valve can serve to control flow and pressure as well as to cut off the flow. For specific design standards and specifications, refer to the following standards: 1. The \"Technical Regulations for Safety in Chemical Production\" (GB 50140-2005) contains relevant provisions on this topic; for example, a shut-off valve should be installed on the inlet pipeline of the pump, and in addition to a shut-off valve, a check valve should also be installed on the outlet pipeline to prevent backflow when the pump stops operating. 2. “Selection Manual for Petroleum and Petrochemical Valves” 3. “Selection Manual for Chemical Process Equipment”. Meanwhile, each enterprise also establishes corresponding corporate standards or operating procedures based on the characteristics of its own equipment and processes. These are all things that can be referenced and followed. In fact, it’s not just cut-off valves; all safety components and auxiliary devices on equipment, although they may seem to result in some waste of resources, can lead to greater losses or even accidents if they fail to function properly when needed. Therefore, we need to consider this issue from a safety perspective. .