Method of producing a flexible pipe and a flexible pipe
US8302634B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 10, 2006 |
| Grant date | Nov 6, 2012 |
| Priority date | — |
| Expiry date | Mar 7, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/1393
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The invention relates to a method of producing a flexible pipe comprising a metal carcass and an internal sealing sheath extruded onto the carcass, said 5 method comprising providing a metal carcass; heating an application section of said carcass, preferably using induction heating, to an application section temperature of at least 150° C.; extruding a non-cross-linked polyethylene material comprising a peroxide having an activation temperature above 150° C. onto said application section of said carcass; cross-linking the extruded 10 polyethylene in a cross-linking zone by raising its temperature to at least the activation temperature of said peroxide by exposing the extruded polymer material to electromagnetic waves, with a wavelength of between 0.5 μm to 0.5 m, preferably infrared radiation; and cooling said cross-linked polyethylene material to obtain the internal sealing sheath. 15 In a preferred embodiment the method comprises heating the application section to an application section temperature of between 30 and 5° C. below the activation temperature of the peroxide. 20 Preferred peroxides include butylcumyl peroxide, dicumyl peroxide, 2,5-Dimethyl-2,5-di(tert-butylperoxy)hex…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.