non-return flap valve

阀门英语大全 ... noncompensated valve 不平衡阀 non-return flap valve 止回阀 non-return foot valve 止回底阀 ...

航海及海运专业英语词汇(N2) ... non-return finger 单向安全销装置 non-return flap valve 止回瓣阀 non-return flap 止回瓣 ...