Research On Apparatus And Craft For Spraying Cylindrical Bores Of Automobile’s Aluminum Engine

Decreasing the weight of engine is an important method for lightweight ofautomobile.Traditional method is that cast iron sleeve is inlayed in cylindrical bores andaluminum alloy is used for outer covering of engine.This method not only have somedefects such as cast iron without mosaic firmly and wear with outer cover of engine,butalso the weight of engine is still massive.With the technology of electric arc spraying cylindrical bores invented,the traditionmethod of inlaying cast iron liner into aluminum alloy engine has been improveddeeply.The volume and weight of engine have been decrensed so much.This method is notonly excellent but also economic method.In recent years electric arc spraying cylindricalbores has been developed quickly.The equipments of the technique are also produced.Byusing this technique,automobile`lightweight is fulfilled efficiently,and it is a trend which ismechanizion process of modern spraying equipment.In this paper,in basis of reform to traditional electric arc spraying equipment,wedesign an electric arc spraying cylindrical bores apparatus with the technology of unifilartungsten.Traditonal design of twin-wire is difficult to fulfill the request.If change thedirection of spraying,it is necessary to make wire bended so that increasing the resistanceof wire feeding.Wire feeding roughly has to affect coat’s quality.With equipment of unifilartungsten,tungsten and wire have an90°angle.High pressure gas blow around tungsten.Inthis way,it can not only fufill the request about direction of sparying cylindrical,but alsowire feeding in straight line.Resistance has alson decrease.With single-wire feeding,thespace of apparatus of wire feeding can decrease and it is easy to fix tungsten.The volumeof whole apparatus can decrease deeply.The apparatus is applied in the above80mm aluminum engine inner’s spraying. Thedimensional drawings and assembly drawings are done by using AutoCAD,and then usingSolidWorks to do3D effect diagram.It is to make some modifications of design by using3D effect diagram before machining.The apparatus is made up of2main parts which is the structure of wire-feeding and spraying.In this research have produced two kinds of electricarc spraying cylindrical bores.Although the original apparatus can make the coat whichfulfill requirements,it is very difficult to apply to cylindrical bore of small size due to largevolume.Through optimization to original apparatus,we have designed and produced a newapparatus with smaller size.Last we practise to make a cylindrical bore coat and do a seriesof tests.Test data shows that the coat with optimized apparatus is fulfill the requests ofsparying cylindrical bores.