The rubber sealing ring inside the pneumatic booster pump is an annular cover composed of one or several parts, which is fixed on one ring or washer of the bearing and contacts with another ring or washer or forms a narrow labyrinth gap to prevent the leakage of lubricating oil and the invasion of foreign objects. The sealing ring is a kind of rubber ring with circular cross section. Because its cross section is O-shaped, it is called O-shaped sealing ring.

一、NBR丁腈橡胶密封圈

1、 NBR nitrile rubber sealing ring

适合于石油系液压油、甘醇系液压油、二酯系润滑油、汽油、水、硅润滑脂、硅油等介质中使用。是目前用途广、成本低的橡胶密封件。不适用于性溶剂之中，例如酮类、臭氧、硝基烃、MEK和氯仿。一般使用温度范围为-40~120℃。

It is suitable for petroleum hydraulic oil, glycol hydraulic oil, diester lubricating oil, gasoline, water, silicone grease, silicone oil and other media. It is a rubber seal with wide application and low cost. It is not suitable for volatile solvents such as ketones, ozone, nitrohydrocarbons, MEK and chloroform. The general temperature range is - 40 ~ 120 ℃.

二、HNBR氢化丁腈橡胶密封圈

2、 HNBR hydrogenated nitrile rubber sealing ring

具有佳的抗腐蚀、抗撕裂和抗压缩变形特性，耐臭氧、耐阳光、耐天候性较好。比丁腈橡胶有更佳的抗磨性。适用于洗涤机械、汽车发动机系统。不建议使用于醇类、酯类或是芳香族的溶液中。一般使用温度范围为-40~150℃。

It has good corrosion resistance, tear resistance, compression resistance, ozone resistance, sunlight resistance and weather resistance. It has better abrasion resistance than NBR. It is suitable for washing machine and automobile engine system. It is not recommended to use in alcohol, ester or aromatic solution. The general temperature range is - 40 ~ 150 ℃.

三、SIL硅橡胶密封圈

3、 SIL silicone rubber sealing ring

具有佳的耐热、耐寒、耐臭氧、耐大气老化性能。有很好的绝缘性能。但抗拉强度较一般橡胶差且不具耐油性。适用于家用电器如电热水器、电熨斗、微波炉等。还适用于各种与人体有接触的用品，如水壶、饮水机等。不建议使用于大部份浓缩溶剂、油品、浓酸及氢氧化钠中。一般使用温度范围为-55~250℃。

It has good heat resistance, cold resistance, ozone resistance and atmospheric aging resistance. It has good insulation. But the tensile strength is worse than that of ordinary rubber and it has no oil resistance. Suitable for household appliances such as electric water heater, electric iron, microwave oven, etc. It is also suitable for all kinds of products that have contact with human body, such as kettle, water dispenser, etc. It is not recommended to use in most concentrated solvents, oil products, concentrated acids and sodium hydroxide. The general temperature range is - 55 ~ 250 ℃.

四、VITON氟素橡胶密封圈

4、 Viton fluororubber sealing ring

耐高温性优于硅橡胶，有佳的耐候性、耐臭氧性和耐化学性，耐寒性则不好。对于大部份油品及溶剂都具有抵抗能力，尤其是酸类、脂族烃、芳香烃及动植物油。适用于柴油发动机、燃料系统及化工厂的密封需求。不建议使用于酮类、低分子量的酯类及含硝的混合物。一般使用温度范围为-20~250℃。

High temperature resistance is better than silicone rubber, has good weather resistance, ozone resistance and chemical resistance, cold resistance is not good. It is resistant to most oils and solvents, especially acids, aliphatic hydrocarbons, aromatic hydrocarbons and animal and vegetable oils. It is suitable for sealing requirements of diesel engine, fuel system and chemical plant. It is not recommended for ketones, low molecular weight esters and mixtures containing nitrate. The general temperature range is - 20 ~ 250 ℃.

五、FLS氟硅橡胶密封圈

5、 FLS fluorosilicone rubber sealing ring

其性能兼有氟素橡胶及硅橡胶的优点，耐油、耐溶剂、耐燃料油及耐高低温性均佳。能抵抗含氧的化合物、含芳香烃的溶剂及含氯的溶剂的侵蚀。一般使用温度范围为-50~200℃。

It has the advantages of both fluorine rubber and silicone rubber, and has good resistance to oil, solvent, fuel oil and high and low temperature. It can resist the erosion of oxygen-containing compounds, aromatic solvents and chlorine containing solvents. The general temperature range is - 50 ~ 200 ℃.

六、EPDM三元乙丙橡胶密封圈

6、 EPDM EPDM sealing ring

具有很好的耐候性、耐臭氧性、耐水性及耐化学性。可用于醇类及酮类，还可用于高温水蒸气环境之密封。一般使用温度范围-55~150℃。

It has good weather resistance, ozone resistance, water resistance and chemical resistance. Can be used for alcohols and ketones, also can be used for high temperature steam environment sealing. The general temperature range is - 55 ~ 150 ℃.

七、CR氯丁橡胶密封圈

7、 CR chloroprene rubber sealing ring

耐阳光、耐天候性能特别好。不怕二氯二氟甲烷和氨等制冷剂，耐稀酸、耐硅脂系润滑油,但在苯胺点低的矿物油中膨胀量大。在低温时易结晶、硬化。适用于各种接触大气、阳光、臭氧的环境及各种耐燃、耐化学腐蚀的密封环节。不建议使用于强酸、硝基烃、酯类、氯仿及酮类的化学物之中。一般使用温度范围为-55~120℃。

It has good resistance to sunlight and weather. It is not afraid of dichlorodifluoromethane, ammonia and other refrigerants, resistant to dilute acid and silicone grease lubricating oil, but has large expansion in mineral oil with low aniline point. It is easy to crystallize and harden at low temperature. Suitable for all kinds of atmosphere, sunlight, ozone environment and all kinds of fire-resistant, chemical corrosion-resistant sealing links. It is not recommended to use in strong acids, nitrohydrocarbons, esters, chloroform and ketones. The general temperature range is - 55 ~ 120 ℃.