The durability of a piston compressor valve shut-off device
Piston compressors are widely used in industry; there are basically valves that determine their work, thermal conditions, capacity and specific energy consumption. The details are exposed to millions of cycles of varying load; it is essential to know the limit of material fatigue under particular type of load, stress concentration, state and method of surface hardening. The durability of valve's work depends on physic-mechanical characteristics of material and constructive parameters of shut-off device. With the purpose of air disturbing devices reliability improvement the criterion is offered, which allows estimating the durability of piston compressor valve shut-off device and choose their constructive parameters. The criterion contemplates three possible variants: flexural stress is smaller than fatigue limit; flexural stress is bigger than the admitted stress of inflexion; flexural stress is smaller than the admitted stress of inflexion, but bigger than fatigue limit. The given criterion also helps to choose the material for the shut-off device efficiently, regarding its physic-mechanical characteristics and economic efficiency.