METHOD OF PRODUCING SLEEVES FROM SHEET MATERIAL Russian patent published in 2012 - IPC B21D53/10 

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming. Proposed method comprises billet drawing, thermal treatment and sizing of its inner and outer surface as required. Drawing and sizing are performed in die block made up of replaceable female dies and made dies. Sleeves are made in passes. In first pass, profile with OD varying from 1.4 to 1.56 of finished sleeve billet diameter and length varying from 0.4 to 0.5 of finished sleeve billet length, provided clearance between female die and male die making, at least, 1.3 of sheet thickness. In second pass, profile with OD varying from 1.2 to 1.34 of finished sleeve billet diameter and length varying from 0.7 to 0.8 of finished sleeve billet length, provided clearance between female die and male die making, at least, 1.15 of sheet thickness. In third sizing pass, sleeve of uniform cylindrical shape over its entire length is formed, provided clearance between female die and male die making, at least, 1.04-1.06 of sheet thickness. Sleeve finished billet wall thickness equals that of sheet material.

EFFECT: expanded performances.

2 cl, 3 dwg