It is cut or punched by pure graphite sheet or metal (truss plate, flat plate, net) reinforced graphite sheet, with mass of excellent sealing performance, e.g.: thermal stability, self-lubricating, no aging, non-fragility, etc. Under extreme conditions, it can be stably and long-term used, extremely needing no maintenance. The lining material can choose different metal thin sheet. The model can choose without tipping, inner tipping, outer tipping, and inner-outer tipping.
