3000Y ARAMID FIBER YARN
Mainly made of USA or Holland-imported polyaramide ( a chemical synthetic filament of the strength 10 times that of steel), used for braiding of seal packing.

Compressed asbestos sheet are generally cheap, convenient. But the biggest trouble is the charring of rubber and packing, and the low temperature will result in the loosen of material. and finally cause leakage in the joint part or in the shim itself, and agglo-merating, smoking, and the planking are more easy sticking on the flange. Beside, asbestos will cause heavy pollution. So the high-strengh graphite sheet and non-compressed asbestos sheet will be used instead of asbestos materials.