There are many factors effect the accuracy of metal spinning ,such as material type ,equipment property , spinning routine ,the spinning gap (between spinning roller and mold) , the shape of product ,the accuracy of the mold and spinning roller . We will introduce it in the following .
●The hardness: it needs stronger force to make it deformation when the metal is harder .
●The ductility : it can spinning longer height if the ductility is good .
●The internal stress : spinning make the grain refining ,grains are not uniform after spinning causes the internal stress and make the metal part springback ,when the metal spinning is finished and left the mold, it will be ellipse with internal stress .
when you spinhe metal which is soft and ductile ,it is easy to spin the accuracy and the sharp (such as aluminum ) ,if the metal is hard or it with strong internal stress after spinning ,it will be easy to springback and backblow（you can see the image above） , it hard to control the accuracy .
●The accuracy : even though spinning roller can move according to the CNC program ,when the accuracy of machine is not good ,the same position that the machine move different time will change a little ,it effects the spinning gap ,the spinning gap and routine are two key factor to effect deformation and accuracy ,if the gap is bigger than the number we set ,the spinning dimension will change ,if the gap is too little ,it will cause stronger force and damaged the machine ,the metal spinning shell will have unsmooth line .
●The force : Stronger force make metal sheer deformation and grain refining ,if the force is not enough ,it is easy to springback as the internal stress .it is hard to control the accuracy without strong force .
in order to overcome the metal springback and ,except it need the
●The accuracy : It effect the spinning gap also .
●The quantity : We can spin by single roller or double roller , In this picture ,you can see the difference between single spinning roller and double spinning roller in sheer spinning .when the roller extrude the sheet on the mold ,the transformation situation of touching point is different,double spinning roller can process more stable as the balance spinning force ,and the accuracy of diameter is better ,single roller will appear ovality after sheer spinning .Of cause ,the three roller make precision better than double roller .
●the accuracy : it effect the spinning gap also .
●material type : the material of mold effect the mold life ,if the mold wear quickly ,the accuracy of the mold will be worse ,it will effect the spinning gap at last .
it is so important to choose a suitable the spinning path ,it depends on the experience of the technician .
the shape decides the strength of the thin-wall part ,if the strength is stronger ,the internal stress will reduce and ellipse is little .