| 摘要 |
<p>In a packing impregnated with hardened silicone resin, the impregnation is carried out after the packing has been formed from paper which is free from matter contg. amines, e.g. wetting agents, and which has been bonded with a rubber binder free from S or S donors. The pref. binder is nitrile rubber, which is resistant to heat and oil. Rings with cylinder borings, or other metal rings, are pref. applied to the packing before impregnation. The silicone resin is partic. a heat-hardenable poly-addn. silicone, e.g. polymethylvinylsilicone, contg. a Pt catalyst, and contg. less than 5 wt.% of a solvent. The silicone is hardened in situ after impregnation. The method of making the seal is also claimed. Useful esp. as cylinder head packings (claimed) for modern high performance engines. The max. tolerable water pressure is 6-10 bras, compared with the usual 2 bars.</p> |
