Pipe handling system and method of joining pipe sections

Patent metadata

Field	Value
Publication number	US-10788147-B2
Application number	US-201515505295-A
Country	US
Kind code	B2
Filing date	Aug 21, 2015
Priority date	Aug 22, 2014
Publication date	Sep 29, 2020
Grant date	Sep 29, 2020

Abstract

A method of joining a first pipe section to a second pipe section includes positioning the two pipe sections in an end-to-end configuration to define therebetween a joint to be welded, measuring the degree of alignment of the pipe sections when they are in the end-to-end configuration in a position ready for welding, ascertaining the relative movement required of the pipe sections in order to improve their alignment, effecting the relative movement so ascertained, and welding together the two pipe sections. The method may include the use of geometric data of the end of the pipes in order to ascertain the relative movement required of the pipe sections. A control unit may be used to calculate, using such data, a target orientation that lines up the pipe sections. The measuring step may be performed using, for example, a laser or a camera and backlight.

First claim

The invention claimed is:

1. A method of moving a pipe section into a position ready for welding to a pipeline, the method being performed at sea when laying the pipeline to the sea-bed, wherein the method comprises:
holding one end of the pipeline within a J-lay tower on a pipe-laying vessel, the pipeline having a free end which is bevelled ready for welding,
the geometry of the bevelled free end of the pipeline having been characterised and stored in the memory of a control unit,
providing the pipe section having a free end which is bevelled ready for welding,
making measurements of the bevelled free end of the pipe section while the pipe section is outside the J-lay tower,
characterising and storing in the memory of the control unit the geometry of the bevelled free end of the pipe section with the use of such measurements,
the control unit calculating, using the stored characterisations of the geometry of the bevelled free ends of the pipeline and pipe section, a target orientation that lines up the bevelled free ends of the pipeline and the pipe section, and
the control unit determining, prior to moving the pipe section into the J-lay tower, whether or not the geometry of the free end of the pipe section is sufficiently closely matched to the geometry of the free end of the pipeline for the pipe section to be suitable for welding to the pipeline, the geometry not being sufficiently closely matched if the control unit calculates that the pipe section and the pipeline cannot be aligned in a way that would meet a predetermined criteria for maximum and/or average hi-lo values between the beveled free ends of the pipe section and the pipeline;
effecting movement of the pipe section, determined to be suitable, relative to the pipeline in dependence on the target orientation so calculated and bringing the pipe section and the pipeline into contact in a position ready for welding the two free ends together, the two free ends thereby defining a joint to be welded; and
measuring, using a measurement system positioned outside the pipe section, a hi-lo value at a plurality of locations on the outer profile of the joint to be welded, the plurality of locations each being at a different angular position around the joint to be welded;
wherein the measurement system includes an imaging camera and a light source and measuring the hi-lo value includes illuminating the joint to be welded with the light source, viewing the joint to be welded with the imaging camera in a tangential direction and capturing, with the imaging camera, an image of a silhouette of the joint to be welded, wherein the hi-lo value can be measured in the image.

2. A method of moving a pipe section into a position ready for welding to a pipeline, the method being performed at sea when laying the pipeline to the sea-bed, wherein the method comprises:
holding one end of the pipeline within a J-lay tower on a pipe-laying vessel, the pipeline having a free end which is bevelled ready for welding,
the geometry of the bevelled free end of the pipeline having been characterised and stored in the memory of a control system,
providing the pipe section having a free end which is bevelled ready for welding,
making measurements of the bevelled free end of the pipe section,
characterising and storing in the memory of a control system the geometry of the bevelled free end of the pipe section with the use of such measurements,
the control unit calculating, using the stored characterisations of the geometry of the bevelled free ends of the pipeline and pipe section, a target orientation that lines up the bevelled free ends of the pipeline and the pipe section,
effecting movement of the pipe section relative to the pipeline in dependence on the target orientation so calculated and bringing the pipe section and the pipeline into contact in a position ready for welding the two free ends together, the two free ends thereby defining a joint to be welded, and
measuring, using a measurement system positioned outside the pipe section, a hi-lo value at a plurality of discrete locations on the outer profile of the joint to be welded when the free ends of the pipeline and pipe section are in an end-to-end configuration, the discrete locations each being at a different angular position around the joint to be welded,
the control unit using the measured hi-lo values and the stored characterisations of the geometry of the bevelled free ends of the pipeline and pipe section to calculate one or more hi-lo values at one or more further locations around the joint to be welded,
the one or more further locations each having an angular position around the joint to be welded different to the angular positions of the discrete locations at which the measurements of the hi-lo value are taken.

3. A method according to claim 2 , wherein the hi-lo value is measured in ten or fewer angular positions around the joint to be welded.

4. A method according to claim 1 , comprising the control unit using the measured hi-lo values and the stored characterisations of the geometry of the bevelled free ends of the pipeline and pipe section to calculate one or more hi-lo values at one or more further locations around the joint to be welded,
the one or more further locations each having an angular position around the joint to be welded different to the angular positions of the locations at which the measurements of the hi-lo value are taken.

5. A method according to claim 2 , wherein the step of the control unit calculating the target orientation uses the stored characterisations of the geometry of the bevelled free ends of the pipeline and pipe section and the measured hi-lo values to determine the relative orientation of the pipeline and pipe section.

6. A method according to claim 2 , wherein the measurement system includes an imaging camera and the step of measuring the hi-lo value includes viewing the joint to be welded with the imaging camera in a tangential direction.

7. A method according to claim 2 , wherein the measurement system includes an imaging camera and a light source and the step of measuring the hi-lo value includes illuminating the joint to be welded and capturing with the imaging camera an image of a silhouette of the joint to be welded at each of a plurality of locations around the circumference of the joint to be welded, wherein an external root hi-lo value can be measured in the image.

8. A method according to claim 2 , further comprising a step of measuring any gap or gaps between the end faces of the pipeline and the pipe section at the joint to be welded.

9. A method according to according to claim 1 , wherein the method includes a step, performed after the step of effecting movement of the pipe section relative to the pipeline in dependence on the target orientation, of verifying the achieved alignment by ascertaining the degree of alignment of the pipe sections.

10. A method according to claim 9 , wherein
the method includes a step of welding together the pipe section and the pipeline, and wherein
after the achieved alignment has been verified, the pipe section is not moved relative to either the free end of the pipeline or the J-lay tower until after the welding step has been completed.

11. A method according to claim 9 , wherein there is a subsequent step, performed when the achieved alignment is deemed not acceptable when performing the step of verifying, of further repositioning the pipe section relative to the free end of the pipeline.

12. A method according to claim 1 , wherein the method includes determining a sequence by which a plurality of pipe sections are to be welded to the end of the pipeline in dependence on the geome

Assignees

• Saipem Spa

Inventors

• Bonel Paolo
• Granelli Lorenzo

Classifications

• B23K31/02

  relating to soldering or welding · CPC title

• B63B35/03

  Pipe-laying vessels (laying pipes under water F16L1/12) · CPC title

• F16L13/02

  Welded joints · CPC title

• F16L1/19

  the pipes being J-shaped · CPC title

• F16L1/207 Primary

  Pipe handling apparatus · CPC title