Sliding Ring Combined Sealing Performance Of High Speed And High Temperature Rotary Shaft

In the aerospace products development and manufacture, high speed rotations are often performed under the conditions of high pressure gas; the required high-pressure gas pressures and rotating speeds has continued to rise with increasing technical level,and higher demands have been made on the test equipment’s rotary shaft seal reliability and safety under high speed and high pressure. Therefore, it is highly necessary to research on the seal structure under the conditions of high speed, high pressure, and rotating, meanwhile is of importance to the aerospace products development.Aiming at real working condition requirements in this paper, two types of slip-ring combination sealing rings, which were made of modified PTFE based materials, were selected to do the research. Seal structure was designed, calculation model and element model were established, and element analysis was performed on the two types of slip-ring combination sealing. Results show that: gear form slip-ring combination sealing rings maximum contact stress was affected more by O seal ring precompressed length and pressure; square slip-ring combination sealing rings maximum contact stress was located on the contact area between O seal ring and slip ring, contact stress of slip ring and rotational shaft was affected less by the O seal ring precompressed length and pressure, high pressure maximum contact stress was found off-center, and easily resulted in damage by uneven friction contact surface stresses.Experimental facility was designed for high speed and high pressure rotational shaft sealing performance. Components and principle were introduced, key parts of the experimental facility were designed, control systems were designed, high pressure air charging system was designed, testing instrument and apparatus were introduced,testing seal ring models and sizes were determined.Wear performance tests were performed. By the timing experiments of testing seals under different rotating speed, different gas pressure, and different O seal ring precompressed length, analyses were made on different effect degrees of experimental results by different experimental factors. Results show that: there were no big seal performance differences between the two types of testing seals under low pressure and low speed, and the seal performance of gear form slip-ring combination sealing was much better.Life tests were performed. Under the condition of 35 MPa gas pressure and1200 rpm rotate speed, two testing seals’ s sealing lives were checked. Results showthat: under the high-speed and high-pressure,tooth and sliding ring combined seal ring seal service life is nearly 3 times square sliding ring combined seal seal life. The live of tooth and sliding ring combined seal ring is larger than the special O-ring used in actual work shaped sealing life of the sealing ring. Therefore, the tooth and sliding ring combined seal can completely replace the existing sealing types. the application of the combined seal can greatly improve the reliability of the equipment, to provide test security conditions of aerospace products development and production.