Mandrel for cold drawing and/or sizing tubes
AssigneeGranges Nyby AB
InventorBernhard Max Willimzik
Life of this patent
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Abstract
A mandrel, in particular a floating mandrel, for the cold drawing and/or sizing of tubes comprising a drawing portion and a shoulder portion section, wherein corresponding to the various functional requirements which are made of its different sections the mandrel consists of two or more different portions which are joined to form a resilient structure and comprise between them at least one intermediate space whose volume is variable by resilient deformation of the mandrel portions and/or relative movement of the mandrel portions with respect to each other, and is substantially completely sealable by engagement of the mandrel portions on the inner wall of the tube to be drawn.
Claims20
A floating mandrel for the cold drawing and/or sizing of tubes comprising:
- a drawing portion engageable with inside walls of a tube during drawing operations,
- a shoulder portion also engageable with inside walls of a tube during drawing operations, said shoulder portion being axially spaced from said drawing portion with its shoulder and drawing portions defining a lubricant space therebetween, said lubricant space being delimited in a direction transverse to the drawing axis of said mandrel by a tube being drawn when said mandrel is in an in-use drawing position,
- and movement accommodating means for accommodating relative axial movement of said drawing portion and said shoulder portion to thereby vary the volume of said lubricant space and create a pumping effect on lubricant in said lubricant space during drying operations.
Dependencies are inferred from the claim text.