Method of forming corrugated tubing using a mandrel having inflatable sleeves adjacent the ends
Abstract
Abstract A method for forming corrugated tubing is disclosed. The corrugated tubing is formed from a cylindrical uncured tube of plastically deformable material. Such tube is inflated in a separable mod to an intermediate shape in which shallow extended corrugations are provided. The intermediate tube is subsequently placed on a curing mandrel in the final shape required and is cured. The apparatus for forming the intermediate tube includes separable mold halves each consisting of a plurality of separate corrugation forming sections and two end forming sections. The initial tube is positioned over an inflatable mandrel having spaced elastic sleeves and is enclosed within the mold halves. The sleeves extend to deform the ends of the initial tube and form a seal therewith. Subsequently, air under pressure is admitted to the interior of the tube to complete its inflation. The number of corrugations formed in the tube can be changed by removing or inserting corrugation forming sections in the active portion of the mold halves. Similarly, the type of end formed on the tube can be changed by changing the end forming sections in the mold halves.
Inventors
- 👤 J Stefanka
Bibliographic Details
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