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