Manufacturing Process And Application Of A Certain Type Of Air-speed Pipe

Air pressure sensor,commonly known as air speed tube,is an aerodynamic instrument that collects the total pressure and static pressure signal of the aircraft during flight.The air pressure sensor is installed outside the skin and exposed to the external atmosphere.Its working environment is the external environment of the flight: the cruise is low temperature,low pressure and high wind speed;the pressure,temperature and wind speed change dramatically with height and speed.Therefore,the air speed tube adopts metal structure and built-in heater for anti-icing.This paper with a model empty speed tube as the research object,this paper introduces its structure composition,design principle and manufacturing process,for empty speed tube manufacturing process of poor insulation,welding quality problems,focusing on heater winding wire,empty speed tube welding and surface treatment process for the key equipment development,process improvement and parameter optimization:(1)For a type of air speed tube heater in the process of winding insulation leads to air speed tube performance failure aircraft safety problems,designed a biaxial linkage mechanism around wire instead of artificial wire method,through the PLC program accurate control,around the wire tension and winding speed parameter optimization,reasonable solve the repeated system,heating wire skin chapped.The optimized process makes the surface diameter change of the heater controlled within 0.00-0.04 mm,and the qualified rate of the product is increased from 75% to 95%.(2)In view of the problems of false welding and excessive welding tumor,the high frequency imitation welding technology with temperature sensor is used instead of flame brazing.PLC controlled programming and optimized the welding power parameters and time.By comparing the welding results of imitation brazing and manual brazing,the destructive test results show that the imitation welding process effectively improves the tensile force of the air speed pipe by nearly 30%.Both the density inside the weld and the welding hard force have been greatly improved,in which the number of welding gaps is greatly reduced by 30%.(3)For the large production of a certain type of empty speed tube,the appearance quality of the product requires high demand,the development of mechanical hand polishing machine instead of manual polishing polishing technology.Using the residual processing process,the product is led and reconstructed,and the corresponding six joint angles of the robot are solved according to the corresponding processing point information.Through online programming,the trajectory motion of the robot sand belt grinding air speed tube is realized,and the application control method of automatic grinding of the air speed tube is completed.Finally,the grinding quality of the surface is 26 m/s when the sand belt line speed is good.The grinding efficiency was improved by 50%,the surface roughness was reduced by 0.022μm in the web position,the weld position was reduced by 0.018μm,and the pipe position was reduced by 0.29μm.