2results about How to "Eliminate complex processes" patented technology

This invention provides a composite static and fatigue testing apparatus for aero-engine shaft components, comprising a load-bearing frame, a torque loading device, a shaft clamping device, a loading actuator, a torque limiting device, an axial force and bending moment loading device, and a test shaft. The shaft clamping device includes a lower connecting shaft, a deep groove ball bearing, and a lower bearing section, used to connect and fix the test shaft and connect the torque loading device and the axial force and bending moment loading device, and to transfer the load to the load-bearing frame. The torque limiting device and the axial force and bending moment loading device are used to load the required axial force and rotational bending moment onto the test shaft, and to decouple the loading of axial force and rotational bending moment. The shaft clamping device is connected to the torque loading device. The shaft clamping device is equipped with a lower connecting shaft, a deep groove ball bearing, and a lower bearing section, so that the axial force and rotational bending moment can be loaded using the same loading device. It is suitable for testing aero-engine shaft components with different load requirements.

This invention discloses a method for preparing polymethylsilane. The method includes cutting and crushing metallic sodium to obtain sodium fragments; adding the sodium fragments to an organic solvent and heating to a molten state to obtain a mixture; stirring and cooling the mixture to obtain a sodium sand mixture; mixing dichloromethylsilane, tetrahydrofuran, and 15-crown ether-5 and then adding the mixture dropwise to the sodium sand mixture for reaction, followed by cooling, solid-liquid separation, and distillation. This preparation method obtains a sodium sand product with uniform particle size, high activity, and clean surface by rapidly cooling after high-temperature dispersion of metallic sodium in a specific organic solvent system. By adding tetrahydrofuran and 15-crown ether-5 to dichloromethylsilane, the single electron transfer rate of metallic sodium to dichloromethylsilane can be increased, the activation energy of the reaction can be reduced, and the reaction efficiency can be improved. Furthermore, the continuous dropwise addition saves reaction time.