1-1. An advanced injection molding technology is applied;
1-2. The two-phase vulcanized of semi-finished products have adopted temperature-control technology;
1-3. The end fittings assembling with the crimping joint method to meet the international advanced technology;
1-4. The high-temperature and high -pressure vulcanized silicon-rubber double sealing technology is applied to the ends and its technique reaches the domestic top level;
1-5. The material of the end fitting is rare -earth AL element with hot-dip galvanizing;
1-6. The products' mechanical failure load is of little dispersive and high safety;