In the 1990s, the United States Air Force combined IHPTET plan, the parameters for the development of the brush seal identified as: Phase II - temperature 649 °C, sliding speed 247m / s, differential pressure 0.34MPa. Phase III - temperature 760 °C, sliding Speed ​​427m/s, pressure difference 1.0MPa. Various high-parameter brush seals (such as high temperature, high speed, high pressure difference, low hysteresis brush seal, ceramic brush seal) and applied to different parts (such as compressor and turbine Brush seals between grades and tips are under research and development. Brush seals have entered the application and promotion stage of aeroengines. EJ200, V2500, PW4000 series, and F119 engines all use brush seals. The contract specifications are: temperature 649°C, sliding speed 244m/s, differential pressure 4.1MPa. ALLISON company has two kinds of sealing structures for manufacturing and testing: gas bearing profile is spiral groove and Rayleigh ladder. Tester test results show that the two kinds of seal designs can form gas film during work. The spiral groove structure has the highest film stiffness at high speed, and the work performance under low pressure difference and high pressure is good. Working capacity reached: temperature of 649°C, sliding speed of 244m/s, pressure difference of 3.4MPa, measured gas leakage of less than 0.71m3/min (folded into standard state), durability and performance retention. Pressure resistance and leakage performance are significantly better than brush seals. However, the structure and materials still need further development.
Series anchor drilling rig is designed to meet the needs of high speed, high efficiency and high mobility in field drilling. Drilling Rig,Anchor Drilling Rig,Anchor Drilling Machine,Prospecting Drilling Rig Henan YK Prospecting Machinery Co., Ltd , https://www.yyphotovoltaicpilingrig.com
The rigs are featured if reasonable structure, simple operation, easy maintenance and speedy transport.
The maximum drilling depth is 60m-80m, and hole size is 105-203mm.