Method for making hollow tubing having an annular wall of foamed material
Abstract
Abstract A method for continuously forming hollow tubing of foam material comprising a mandrel fixed at one end about which said tubing is formed a web of material by confining the foam material within an annular space of an envelope of flexible laminar material which is allowed to foam and expand and the envelope of confined foamed material then moved longitudinally of said mandrel and thereafter cured while moving along said mandrel. In order to assure cross-sectional symmetry of concentricity of the hollow tubing, means are provided for aligning the mandrel by controlling its flexure to a position which will provide a product having the desired concentricity, and means associated with a region of the mandrel away from the fixed end from detaching variations in alignment from the desired alignment, whereby when a variation in alignment is detected, the means for aligning the mandrel is actuated to compensate for the detected variation.
Inventors
- 👤 J Weller
- 👤 C Snelling
- 👤 T Andrews
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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