The moving part of the valve is a ______(铜环) with _____(凹槽) around the outer perimeter and 3 holes drilled fore and aft.
A.O ring, menber
B.bronze ring， lug
C.grooves, chamber
D.bronze ring，groove
正确答案是D
The moving part of the valve is a ______(铜环) with _____(凹槽) around the outer perimeter and 3 holes drilled fore and aft.
A.O ring, menber
B.bronze ring， lug
C.grooves, chamber
D.bronze ring，groove
正确答案是D