Plastic Pipe with Bell
AssigneesAdvanced Pipe Services, LLC, Unicor GmbH, Profilepipe Machinery Inc.
InventorsTimothy Toliver, Tony Kime, Hubert Kossner
Life of this patent
Estimating the term…
Abstract
A multi-layer bell is formed from the outer shell of a multi-layer pipe in a secondary process, thereby allowing the extrusion process to be conducted at normal speeds. The bell may include a strain limiting membrane fused or mechanically secured between the outer shell extrusion layer and the inner liner extrusion layer, increased hoop or circumferential stiffness. This invention allows the extrusion process to be in its simplest form, with no adjustments to the corrugator or extruder speeds.
Claims20
A method of forming a bell on the end of a plastic pipe, the method comprising the steps of:
- providing a segment of plastic pipe having an inner layer and outer shell attached to the inner layer, a portion of the outer shell having a bell shape adjacent an end of the pipe,
- allowing the bell shaped outer shell portion to cool sufficiently to hold the bell shape,
- reinforcing the bell shaped outer shell portion with an inner liner substantially covering the inner surface of the bell by heating the inner liner and forming the inner liner to the bell shaped outer shell portion.
A corrugated plastic pipe comprising;
- an outer shell having a bell formed on an end portion,
- an annular recess formed in the inner surface of the outer shell bell,
- an annular reinforcing membrane positioned in the annular recess,
- an inner liner attached to the outer shell underneath the bell.
A method of forming a bell on the end of a plastic pipe, the method comprising the steps of:
- providing a segment of plastic pipe having an inner liner and outer shell attached to the inner liner,
- detaching a portion of the outer shell adjacent an end of the pipe from the inner liner,
- forming the detached outer shell portion into a bell shape,
- attaching the inner liner to the outer shell portion.
Dependencies are inferred from the claim text.