Cold forming of ring envelopes - has thin walled steel cylinder and induction coil mounted on chassis with cylinder centering ring

摘要

The metal envelopes for annular sections are cold formed using a thin steel walled cylinder located between the ring to be covered and an induction coil. An intense magnetic field is created around the coil for projecting the cylinder wall against the ring. The impact curles the wall around the outside of the ring. The section is then removed and replaced with the opposite end adjacent the induction coil. The process is repeated with the under-formed cylinder wall section projected against the uncovered ring section. The assembly is mounted on a rigid chassis with a ring for locating the cylinders centrally about the coil.