| Nearly30years, with the change of the international situation and the military situation, the manufacturing technology of aircraft developed very fast. Especially in the field of aircraft engines, there is a big development from the traditional turbo-jet engine to turbo-fan engine. Together with the increasing demands on improving the aircraft technical and tactical performance, accordingly it makes the engine continuously being updated and improved. In the meantime, there will be more and more high requirement on the safety and reliability of the engine. We can say, the improvement and development of the blade is one of the most important changes for each new generation of aircraft engines. This requires the blade manufacturing technology is also constantly upgrading. With the increase of thrust/weight ratio turbofan engine, there is more and more higher requirement on air compression ratio which put forward more higher request on the performance of the stator and rotator blade of the compressor. There are two effective solutions to improve the performance. First, design the blades with high performance and high compression ratio. Second, improve the manufacturing level, especially to improve the R of the leading edge and the trailing edge, waviness and other surface roughness that will affect the aerodynamic performance of the manufacturing level.Machining and polishing method for the blade of the compressor stator vane has been researched in this thesis. The traditional CNC machining for airfoil will result in the big deformation, so the stock removal shall be given more on the airfoil with0.05to0.15mm, the final stock removal will eliminated by hand-polishing operation. However, the blade profile after the hand polishing operation can not guarantee the requirement of the design drawings, the blade profile line compliance rate is lower than40%, the front and back edge R have the problems of square head and migraine generally. Some blades have the problems of over-cut and waspish phenomenon. According to the calculation of the design department, the above issues will reduce the engine performance by about12%to15%.Based on the principle of digital machining technology, vibration and abrasive polishing techniques and streaming technology, combined the structural features of the compressor blade with their design performance requirements, by choice of CNC machines reasonably, good repeatability of the blades is obtained. Through the rational use of CNC cutters, machining parameters, tool path and increasing the heat treatment method etc., control the cutting force as much as possible, then we can achieve the irregular surface deformation process control and control the tolerance of the airfoil after CNC machining enter the design CNC machining tolerance zone. Against the front and back edge R have the problems of square head&migraine generally and some blades have the problems of over-cut and waspish phenomenon, the geometric size and the integrity are completely in line with the design requirement by developing surface finishing equipment, designing the polishing fixture and the breakthrough of key technologies of choosing polishing materials and polishing parameters for high precision polishing.The research results have already been successfully applied to actual production. High precision of CNC machining of biaxial compressor stator blades ensured the machining accuracy and improved the machining efficiency.This technology has significance in the promotion of "no margin" compressor blades and provides a theoretical and technical support for a new generation of aero-engine blade manufacturing. |
PDF Full Text Request