Torque Production Using Hand Cranks in a Simulated Gear-Operated Valve Opening Task

Hand cranks are used in a variety of industries to actuate valves and in other gear-operated applications. In order to evaluate these types of operations and their compatibility with operator strength capabilities, a rotational dynamometer was used to measure torque production capability of operators using a hand crank at different heights and angles (with respect to the coronal plane). The tests were conducted for both clockwise and counterclockwise rotations using the dominant arm of each test participant. A total of 18 tests were completed by each of five male right-handed test participants. A 0° declination angle, counterclockwise operation, and both 40.65 cm and 60.96 cm heights were found to be associated with the greatest torque production capabilities.     

Gear oil formulation designed to meet bio-preferred criteria as well as give high performance

A bio-based gear oil was developed from soybean oil (SBO). The SBO was first thermally polymerised and then mixed with additives and diluents. The effect of pour point depressants, co-base oils, antioxidants and anti-wear additives is reported. Lubricity, viscosity index and oxidation stability of the final formulation of the bio-based gear oil are compared with commercially available gear oils. The final formulation of bio-based gear oil gives test results: viscosity index 165, four-ball wear scar 0.375 mm. These numbers are comparable to or better than the commercially available gear oils tested for comparison. The oxidation onset temperature of the bio-based gear oil, 220°C, is lower than the evaluated commercial products, but still at an acceptable range for gear oil.     

300M钢刷镀镉性能及在某型飞机起落架修理中的应用

目的研究刷镀镉工艺在300M钢起落架的工程应用和镀层性能。方法采用两种不同的刷镀镉溶液在300M钢表面实现外观质量良好的电刷镀镉层,利用扫描电镜、盐雾箱及力学拉伸机等对镀层显微组织、厚度、结合力、耐腐蚀性能和氢脆性能进行测试,并对起落架零件电刷镀修复进行工艺应用研究。结果选用的两种镀液均可在300M表面获得质量稳定,厚度、结合力符合技术要求的电刷镀镉层。该镀层中性盐雾性能超过500 h,氢脆性能合格。结论刷镀镉工艺可成功应用于某型机起落架零件电镀镉钛镀层的修复。     

专用滚压成形设备设计中主要技术分析

介绍了专用滚压成形设备中滚轮及升降装置的设计 ,分析了其技术特点及可行性。