This prevents stem from scoring and galling and provides longer disc seal and body life.
这种结构避免阀杆刮伤和磨损,延长阀瓣密封和阀体的使用寿命.
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Meanwhile, small disc seal base , because gives a discount completely to receive about 10 % falls.
与此同时, 小盘封基由于折价均在10%左右全部收跌.
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