GB1602549A - Pipe spooling reels for use in offshore pipelaying systems - Google Patents

Description

(54) IMPROVEMENTS IN PIPE SPOOLING REELS FOR USE IN OFFSHORE PWELAYING SYSTEMS (71) We, SANTA FE INTER NATIONAL CORPORATION, a Corporation organized and existing under the laws of California, of 505 South Main Street, Orange, California 92668, United States of America, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement : - This invention relates to pipe spooling reels. More particularly, the invention relates to a construction of a pipe spooling reel for use on water-borne vessels, such as barges, ships or the like.

In offshore pipelaying operations employing reel barges or ships, pipe is generally spooled onto the reel located on the vessel at a shore base after short lengths of properly coated pipe have been welded on shore at the base to form a continuous pipeline which is spooled onto the reel The carrier vessel is then towed (or self-propelled) to the job site where the pipe is layed between different points (e.g. between the well completion and a collection or storage point).

U.S. Patent No. 3,680,342, issued August 1, 1972, shows a barge having a reel with flanges located in horizontal planes and having a vertical axis of rotation (generally referred to in the trade as a "horizontal reel").

U.S. Patent No. 3,982,402, issued September 28, 1976, shows a pipelaying vessel having a reel with flanges located in vertical planes and having a horizontal axis of rotation (generally referred to in the trade as a "vertical reel").

The present invention is primarily concerned with the construction of such vertical reels, which have different load and stress characteristics from horizontal reels.

In a commercial operation, pipe is usually spooled onto the reel under tension in order to bend the pipe as it is being spooled onto the reel. The combination of the tension and the weight of the pipe itself create forces which are dissipated by and within the reel; thus the reel should have sufficient strength to prevent it from collapsing in on itself. On the other hand, it is generally preferable and advantageous that the reel not be unduly heavy, particularly where it is to be capable of being mounted on a variety of carrier vessels having different hydrostatic and hydrodynamic characteristics. Because of its height and the fact that the center of gravity of the reel is located substantially at the center of the reel coincident with its rotational axis, a vertical reel can have a greater effect on the carrier vessel's seagoing characteristics than a horizontal reel of comparable size and pipecarrying capacity but having an inherently lower center of gravity.

The present invention therefore provides a relatively strong and relatively light-weight reel construction capable of withstanding the loads imparted thereto by the pipe as it is wound onto the reel under tension.

According to the present invention, we provide a reel for use in laying pipe from a water-borne vessel, comprising: a shaft; first and second sets of radial members extending radially outwardly from the shaft in respective first and second spaced-apart planes substantially perpendicular to the rotational axis of said reel; a plurality of transverse bracing members extending between corresponding opposed first and second radial members substantially parallel to and radially spaced from the shaft, said transverse bracing members supporting substantially continuous plating defining a circumferential substantially cylindrical pipe-supporting surface for supporting pipe spooled on the reel substantially evenly while substantially avoiding localized moments which exceed the elastic range of the pipe; and a plurality of diagonal bracing members extending between said transverse bracing members and said shaft for distributing loads imparted to the reel by the pipe to the shaft, wherein an opposed pair of both first and second radial members, its associated transverse bracing member, and associated diagonal bracing member all lie within a radial plane substantially parallel to said shaft and passing through the rotational axis of said reel, and wherein said diagonal bracing member extends between its said associated transverse bracing member and said shaft in a diagonally opposite direction from the corresponding diagonal bracing members in both immediately adjacent radial planes.

An embodiment of the invention will now be described by way of example with reference to the accompanying drawing, in which: Fig. 1 is a side elevation of a pipe spooling reel of this invention with flange plating removed to show the radial structural members; and Fig. 2 is a plan view of the reel with hub plating removed to show internal bracing.

Referring to the drawing, the pipe spooling reel comprises a shaft 10 seated in respective port and starboard side bearings 12.

The bearings are secured to bearing support plates 14 which rest on support legs 16. The support legs in turn may be secured to a substantially rectangular and horizontally planer skid; alternatively, the legs 16 may be secured directly to the deck of a vessel such as a barge, ship, drilling rig, etc.

A first group of radial members or arms 20 comprising a first, e.g. port side set and a second, e.g. starboard side set, extend from the shaft 10 to the outer rims of respective port and starboard side flanges 22. The radially outer ends of members or arms 20 are connected by chord members 36. A second group of radial members or arms 24 comprising a third or port side set and a fourth or starboard side set, extend from the shaft to the inner surface of the hub, generally designated 26. The first and third or port side sets of radial members or arms 20 and 24 extend with substantial axial symmetry in the plane of the port side flange 22, and the second and fourth or starboard side sets of radial members or arms 20 and 24 extend with substantial axial symmetry in the plane of the starboard side flange 22. Moreover, corresponding radial members or arms 20 of the first and second sets are in the same radial plane and coresponding radial members or arms 24 of the third and fourth sets are in the same radial plane. Thus the first and second sets of radial members or arms 20 comprise first and second sets of transversely opposed bracing members and the third and fourth sets of radial members or arms 24 comprise third and fourth sets of transversely opposed bracing members. The radial members or arms 20 and 24 alternate on each of the port and starboard sides of the reel and may be secured, e.g. by welding, directly to shaft 10 or to one or more corresponding port and starboard side termination plates, e.g. plates 28 and 30, as shown, which in turn are secured to the shaft 10. The use of such termination plates may be desirable or required where the shaft does not have enough surface area to accommodate securing all of the radial arms directly thereto.

Transverse hub frame members 32 extend between corresponding port and starboard side radial arms 20 and 24, respectively, to provide support for the hub surface plating 27.

Diagonal bracing members 34 and 34' extend between the interior surface of hub 26 and the shaft 10. More particularly, a given diagonal bracing member 34 has one end secured approximately at the intersection of a given transverse member 32 and the outer end of a given starboard side radial arm 24; the other end of diagonal bracing member 34 is secured approximately to the intersection of shaft 10 and the radially inner end of the corresponding port side radial arm 24. A diagonal bracing member 34' has one end secured approximately at the intersection of a transverse support member 32 and a port side radial arm 20; the other end of diagonal bracing member 34' is secured approximately at the intersection of the corresponding starboard side radial arm 20 and the shaft 10. Thus the directions of the diagonal bracing members alternate around the reel.

Flange plating extends circumferentially around the reel at least between the hub 26 and the radially outer ends of arms 20 to provide a continuous and laterally even pipe support. The rim of one flange, e.g. the starboard flange, preferably and advantageously supports a chain or sprocket arrangement extending circumferentially around the flange rim; the chain or sprocket 40 mates with a gear of one or more drive motors (not shown) for driving the reel in rotational movement.

A principal feature of the reel construction described here is the means for translating lateral motion induced loads of the reel and pipe to the axle shaft substantially coincident with the centerline of the reel. Such means include the diagonal bracing member 34, 34'.

The forces imparted to the reel hub by the pipe have components in the transverse and radial directions which are distributed through transverse members 32 and radial arms 20, 24, respectively. The resultants of the transverse and radial force components are transmitted to the shaft 10 in the region of port and starboard side support bearings 12 by diagonal bracing members 34, 34'. It should be noted that the diagonal bracing members 34, 34' need not intersect transverse members 32 at their ends. Other locations of the connection between transverse members 32 and diagonal members 34, 34' are envisaged, so long as the function of the diagonal members 34, 34', i.e., transmitting the resultants of the transverse and radial forces to the shaft, is maintained and the diagonal members extend between the transverse members 32 and the shaft 10.

The reel construction described here further includes the following features: alternating long and short radial ribs or arms; crossbeams to provide lateral support for the reel framework and to provide support for the hub surface plating; the hub and flange plating which supports the pipes evenly as it is spooled onto the reel to avoid localized moments which may exceed elastic limit of the pipe; chords which provide a means for transmitting spooling and braking torque from the drive mechanism which carry the load in the flange plane.

The invention may be embodied in otter specific forms without departing from the scope of the invention as defined in the appended claims. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description.

WHAT WE CLAIM IS:- 1. A reel for use in laying pipe from a water-borne vessel, comprising: a shaft; first and second sets of radial members extending radially outwardly from the shaft in respective first and second spaced-apart planes substantially perpendicular to the rotational axis of said reel; a plurality of transverse bracing members extending between corresponding opposed first and second radial members substantially parallel to and radially spaced from the shaft, said transverse bracing members supporting substantially continuous plating defining a circumferential substantially cylindrical pipe-supporting surface for supporting pipe spooled on the reel substantially evenly while substantially avoiding localized moments which exceed the elastic range of the pipe; and a plurality of diagonal bracing members extending between said transverse bracing members and said shaft for distributing loads imparted to the reel by the pipe to the shaft, wherein an opposed pair of both first and second radial members, its associated transverse bracing member, and associated diagonal bracing member all lie within a radial plane substantially parallel to said shaft and passing through the rotational axis of said reel, and wherein said diagonal bracing member extends between its said associated transverse bracing member and said shaft in a diagonally opposite direction from the corresponding diagonal bracing members in both immediately adjacent radial planes.

2. A reel according to claim 1, wherein: said circumferential substantially cylindrical surface comprises the reel hub radially spaced from said shaft and onto which pipe may be wound; said spaced-apart planes define respective first and second flange portions of the reel which in turn define the width of the hub, said flange portions extending radially outwardly from said shaft to a greater distance than said hub portion; and said first and second sets of radial members comprise first and second sets of transversely opposed bracing members extending radially outwardly from said shaft in the plane of said first and second flange portions respectively, to a distance substantially equal to the circumferen- tial surface of said flange portion; and further comprising third and fourth sets of transversely opposed bracing members extending radially outwardly from said shaft in the plane of said first and second flange portions respectively, substantially only to the inner surface of said hub portions, wherein said second plurality of bracing members provide support for said hub on said reel. ~ 3. A reel according to claim 2, wherein said third and fourth sets of bracing members alternate with said first and second sets of bracing members, respectively, in the planes of said first and second flange portions, respectively.

4. A reel according to any one of the preceding claims, wherein said diagonal bracing members and said shaft define an acute angle of less than 900 and wherein said diagonal bracing members translate vertical components of force imparted to the reel hub by pipe spooled thereon inta horizontal components of force at the shaft.

5. A reel for use in laying pipe from a water-borne vessel, substantially as hereinbefore described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. members 32 and the shaft 10. The reel construction described here further includes the following features: alternating long and short radial ribs or arms; crossbeams to provide lateral support for the reel framework and to provide support for the hub surface plating; the hub and flange plating which supports the pipes evenly as it is spooled onto the reel to avoid localized moments which may exceed elastic limit of the pipe; chords which provide a means for transmitting spooling and braking torque from the drive mechanism which carry the load in the flange plane. The invention may be embodied in otter specific forms without departing from the scope of the invention as defined in the appended claims. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description. WHAT WE CLAIM IS:-

1. A reel for use in laying pipe from a water-borne vessel, comprising: a shaft; first and second sets of radial members extending radially outwardly from the shaft in respective first and second spaced-apart planes substantially perpendicular to the rotational axis of said reel; a plurality of transverse bracing members extending between corresponding opposed first and second radial members substantially parallel to and radially spaced from the shaft, said transverse bracing members supporting substantially continuous plating defining a circumferential substantially cylindrical pipe-supporting surface for supporting pipe spooled on the reel substantially evenly while substantially avoiding localized moments which exceed the elastic range of the pipe; and a plurality of diagonal bracing members extending between said transverse bracing members and said shaft for distributing loads imparted to the reel by the pipe to the shaft, wherein an opposed pair of both first and second radial members, its associated transverse bracing member, and associated diagonal bracing member all lie within a radial plane substantially parallel to said shaft and passing through the rotational axis of said reel, and wherein said diagonal bracing member extends between its said associated transverse bracing member and said shaft in a diagonally opposite direction from the corresponding diagonal bracing members in both immediately adjacent radial planes.

2. A reel according to claim 1, wherein: said circumferential substantially cylindrical surface comprises the reel hub radially spaced from said shaft and onto which pipe may be wound; said spaced-apart planes define respective first and second flange portions of the reel which in turn define the width of the hub, said flange portions extending radially outwardly from said shaft to a greater distance than said hub portion; and said first and second sets of radial members comprise first and second sets of transversely opposed bracing members extending radially outwardly from said shaft in the plane of said first and second flange portions respectively, to a distance substantially equal to the circumferen- tial surface of said flange portion; and further comprising third and fourth sets of transversely opposed bracing members extending radially outwardly from said shaft in the plane of said first and second flange portions respectively, substantially only to the inner surface of said hub portions, wherein said second plurality of bracing members provide support for said hub on said reel. ~

3. A reel according to claim 2, wherein said third and fourth sets of bracing members alternate with said first and second sets of bracing members, respectively, in the planes of said first and second flange portions, respectively.

4. A reel according to any one of the preceding claims, wherein said diagonal bracing members and said shaft define an acute angle of less than 900 and wherein said diagonal bracing members translate vertical components of force imparted to the reel hub by pipe spooled thereon inta horizontal components of force at the shaft.

5. A reel for use in laying pipe from a water-borne vessel, substantially as hereinbefore described with reference to the accompanying drawings.