| 摘要 |
PURPOSE:To obtain a pipe material which is impermeable, high resistant to thermal shock and mechanical shock and usable even at elevated temperature by coating a swollen graphite sheet with a specific adhesive or a heat-resistant, corrosion-resistant composition, forming the product into pipes, curing with heat and firing the product. CONSTITUTION:A swollen graphite sheet material is coated with a phenolic adhesive comprising a graphite powder, phenolic resin fine particles of more than 10,000 weight-average molecular weight and 1 to 200 micron particle sizes and a resol type phenolic resin varnish, or a heat-resistant, corrosion-resistant composition mainly containing a metal alcoholate and then formed into pipes. The pipes are cured with heat and roasted in an inert atmosphere at a temperature higher than about 1,000 deg.C to obtain the subject impermeable heat-resistant pipe material. The curing is conducted by heating at 150 to 300 deg.C for about 1 hour to 6 hours. The roasting is carried out, for example, by elevating temperature up to 1,000 deg.C in 2 to 72 hours and maintaining 1,000 deg.C for 1 to 5 hours. |
