The valve is closed by swinging the valve element through {HEAD ~ 90 degrees} thus moving the valve element passage out of registry with the ports 13 13 of {TAIL ~ the chamber} 
The valve is closed by swinging the valve element through { HEAD ~ 90 degrees } thus moving the valve element passage out of registry with the ports 13 13 of { TAIL ~ the chamber }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL