MATERIAL USED FOR EXPANDED GRAPHITE GLAND PACKING, EXPANDED GRAPHITE GLAND PACKING MADE THEREOF, AND MANUFACTURE OF EXPANDED GRAPHITE GLAND PACKING

摘要

PROBLEM TO BE SOLVED: To improve sealing performance using a material formed by twisting a laminated sheet formed by laminating a polyethylene tetrafluoride film on one face of an expanded graphite sheet and providing a polyvinyl alcohol layer on the other face and using it as a braiding yarn used for expanded graphite gland packing. SOLUTION: Expanded graphite gland packing is provided by pressure forming a braid body formed by braiding a braiding yarn for which a material formed by twisting a laminated sheet 4 is used. The laminated sheet 4 is formed by cutting a laminated sheet into bands and the laminated sheet formed by laminating a polyethylene tetrafluoride film 7 on one face of an expanded graphite sheet 6 and providing a polyvinyl alcohol layer 8 on the other face is used for it. The expanded graphite sheet 6 is so formed that graphite powder is reacted into an interlayer compound, it is decomposed into residual compound, and the expanded flexible graphite obtained by expanding it is compressed and formed into the sheet.