The spring - loaded excess - pressure safety valve protects the pump as well as the gearbox from overload which may arise from an erroneously closed sluice valve or alternatively due to a blocked discharge pipe etc 弹簧超压安全阀对泵及齿轮箱起着保护作用,使其避免由于出口阀门的误关或管道的堵塞而引起的超载。