These sealing areas are preferably made by coating or impregnating {TAIL ~ these areas} of the substrate with a silicon carbide powder bonded together with about 2% of {HEAD ~ Teflon} or Teflon like polytetrafluoroethylene material to hold the powdered material in its compacted condition 
These sealing areas are preferably made by coating or impregnating { TAIL ~ these areas } of the substrate with a silicon carbide powder bonded together with about 2 % of { HEAD ~ Teflon } or Teflon like polytetrafluoroethylene material to hold the powdered material in its compacted condition
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH