US 11,376,644 B2 · Pipe bending for reel-lay operations

Abstract

A method and apparatus for bending a pipe to mitigate internal wrinkling, with particular benefit when bending a lined pipe upon spooling. Bending is performed continuously by advancing the pipe through a bending zone while an internal mandrel is held at the bending zone to resist wrinkling. In one variant, the mandrel comprises longitudinally-spaced pipe-engaging elements and a tensile link between the elements allows relative movement between the elements. A holdback connection on one of the elements applies hold-back force to that element to be transmitted to the other element via the tensile link. In another variant, the mandrel comprises an elongate pipe-engaging body with a hold-back connection at one end of the body. The body is flexible to bend with the pipe and is shaped to engage an inner surface of the pipe along most of the length of the body.

Claims13

Dependent claims

An internal mandrel for resisting radially-inward deformation of an inner surface of a pipe during bending of the pipe along a longitudinal axis, the mandrel comprising:

longitudinally spaced pipe-engaging elements;
a tensile flexible or hinging link disposed between the pipe-engaging elements to allow relative angular movement between the pipe-engaging elements as the pipe bends;
a hold-back connection on one of the pipe-engaging elements to apply hold-back force to that pipe-engaging element, whereby the hold-back force is transmitted in use to another of the pipe-engaging elements by tension in the tensile link;
a pressure-equalisation duct extending longitudinally through the pipe-engaging elements of the mandrel;
and
a pressure compartment defined between the pipe-engaging elements;
wherein the pressure compartment contains a fluid mass;
and
wherein the fluid mass comprises a gel, wax or granular filler material.

6 more elements

A pipe-bending apparatus for bending an elongate pipe section continuously along a longitudinal axis of the pipe section;

the apparatus comprising:
an internal mandrel arranged to fit inside the pipe section to resist radially-inward deformation of an inner surface of the pipe section with respect to the longitudinal axis during bending;
an elongate tensile hold-back element arranged to extend internally along the pipe section from an external anchor to the internal mandrel to hold the internal mandrel at a bending zone as the pipe section advances longitudinally past the internal mandrel;
pressure-equalisation duct extending longitudinally through the pipe-engaging elements that form ends of the internal mandrel;
an external mandrel defining the bending zone;
and
a drive for advancing the pipe section through the bending zone;
wherein a reel serves as the external mandrel and as the drive
wherein the internal mandrel is comprising:
longitudinally-spaced pipe-engaging elements;
a tensile flexible or hinging link disposed between the pipe-engaging elements to allow relative angular movement between the pipe-engaging elements as the pipe bends;
and
a hold-back connection on one of the pipe-engaging elements to apply hold-back force to that pipe-engaging element, whereby the hold-back force is transmitted in use to another of the pipe-engaging elements by tension in the tensile link;
and
a pressure compartment is defined between the pipe-engaging elements;
wherein the pressure compartment contained a fluid mass;
and
wherein the fluid mass comprises a gel, wax or granular filler material.

15 more elements

Dependencies are inferred from the claim text.

Pipe bending for reel-lay operations

Life of this patent

Pipe bending for reel-lay operations

Life of this patent

Abstract

Claims13