METHOD FOR PRODUCTION OF TUBULAR METAL SHELLS Russian patent published in 1994 - IPC

FIELD: instrument-making industry. SUBSTANCE: method for production of tubular metal shells consists in drawing cups of sheet material with following thinning of cup walls. Then are performed successively the strength reducing thermal treatment, cup walls cold work hardening, electrical polishing of each cup with total removal of material not exceeding 5% of the initial thickness of the cup wall (in several stages, on a party of not less than five cups). Residual hoop elastic stress in the area of cup dome passes into the cylindrical section is defined after each stage of electric polishing. The stress dependances of the thickness of the material removed by electrical polishing are plotted; the thickness of the removed material corresponding to the extreme residual hoop elastic stress and to the half value of the said are determined. Then the production of tubular shells continues, with the electrical polishing removing material in quantities laying within the said determined values. EFFECT: improved technology. 3 dwg