Assertion: valve's thread | /r/HasProperty | protected in the main
Facets:
value: from the fluid
type: OTHER
Source sentences:
text: The present invention relates to an improved gate valve structure and, more particularly, to a gate valve structure wherein telescoping upper and lower stems are'provided for actuating the valve gate member, the stems threadedly engaging one another with the threads being protected from the fluid in the main at all positions of operation of the valve.