1. Ningbo Zhonggao SealHad own mold department more than 20000 size mold , Inner diameter from 0.05mm to 1.2m, C/S from 0.5mm to 20m can be a molding for one time shape, biggest ID can made over 6m , C/S over 30m 2. NBR materia withstand high and low temperatures from -40° To 120° 3. Applied industry: chemical industry, petroleum Industry, medical technique, food industry, sewage-disposal industry, steel industry, and so on. 4. Applied equipment: Mechanical sealing, pressure vessel, gas compressor, reaction vessel, heat exchanger, boiler, filter and so on. 5. Main advantage: First, excellent anti-chemical character. It almost applies to all mediums. Second, temperature range is very wide. (Around -30° C to200° C) Third, anti-compressibility function is very good. Four , Oil proof, Alkali resistance, good elastic and long lifespan 6. Operation conditions: Pressure: <=50mpa 7. In house tool making and free of tooling charge for standard rubber ring, the mold line can be 45° and 180°.