Optimization Of Welding Process Of Aircraft Engine Disc Seal Seat

Sealing device is an important part of aero-engine.With the development of the research on the flow loss in the engine,more and more attention has been paid to the sealing performance and assembly accuracy of the sealing parts.In this thesis,the sealing seat component of aero-engine is taken as the research object,its welding process is optimized deeply,and production verification is carried out to improve sealing performance and reduce welding distortion.The welding parameters,welding methods,welding forms and post-welding correction of seal assembly are optimized and improved.Firstly,the structure of the sealing seat component of the aero engine is dissected,the structural form of each component is analyzed,the difficulties of machining are expounded,and the corresponding improvement measures are formulated.Secondly,the brazing process of the inserted joint structure of 0Cr18Ni9 and TC4 with different sealing materials was optimized to improve the sealing performance of sealing base.The experimental results show that the brazed joint with the seal seat and the oil leakage pipe can be obtained with good sealing performance when the silver-based BAg72 CuNiLi is adopted in the form of thin sheet winding oil leakage pipe and the brazing clearance is controlled at 0.1mm.Thirdly,for the four butt joint ring joints on the inner and outer walls of the sealing seat,the original argon arc welding process is replaced by the electron beam welding,and the bottom lock structure is added to the mounting edge.Compared with the data of argon arc welding,the coaxiality correction of inner and outer walls of sealing base reached 0.4mm,cylindrical degree correction 0.3mm and height correction 0.2mm.Therefore,electron beam welding is advantageous in welding deformation control than argon arc welding for titanium alloy thin-walled circular parts.This is primarily due to the smaller heat input and parallel weld of electron beam welding which is proved by metallographic observation.Finally,starting from the post-weld deformation correction and taking the data indexes that affect the function characteristics of seal seat as the design principle,the thermal setting tooling is designed to correct the deformation of seal seat.The results show that the thermal setting tooling has a certain effect on the size correction of seal seat,and the correction of coaxiality and cylindrical degree reaches 0.12mm~0.17 mm,but has no obvious effect on the part height.The research results have been applied to the field production guidance of sealing seat,and the sealing performance and assembly precision of sealing seat have been improved obviously.