TPI November 2015

59 / 64

November 2015 Tube Products International 57
properties of the material used. The parameters are therefore
monitored by means of a data acquisition unit, which records
data in real time. This manufacturing concept offers flexibility
through independent installations for all phases of preparation.
A second method consists of a complete, fully automatic
machine integrating four operations: cutting, dressing/
bevelling, welding, and polishing. The equipment is mounted
on a motor-powered trolley. Utilities and connection bundles
are conveyed via cable-carrier chains. The welding power
source is also mounted on the trolley transporting the welding
head. This automated configuration integrates all phases of
tube assembly.
Umbilical construction
Once the various constituent tubes have been made, the
umbilical is bundled to gather the tubes, tube separators,
electrical cables and fibre optic cables together in a single
strand. Depending on the manufacturer, the bundles are
assembled either horizontally or vertically. The umbilical
bundling system can take up to a dozen of these large
spools of stainless steel piping, of various inside and outside
diameters.
The contents of the spools are fed to an assembly structure
where the super-duplex pipes are wound around a larger pipe
forming the core of the umbilical. The umbilical can then be
armoured, or pre-encased in a plastic sheath, before finally
undergoing an extrusion operation in which it is covered with
a PE sleeve.
As various diameters of tubing are used in the construction
of umbilicals, the spools contain different lengths of tubing,
which means that they often have to be changed before the
umbilical is completed. The assembly operation is suspended
while the empty spool is replaced by a new one. A welder then
steps in with a Polysoude mobile orbital welding set to butt
the new tube to the end of the previous one.
Connecting umbilicals to the UTH
Umbilicals are joined to an umbilical termination head (UTH)
via connectors that are welded to the various constituent
tubes of the umbilical. A Polysoude MU low profile head is
used to make the joint.
At each stage of the manufacturing process, the Polysoude
orbital or automated TIG installation ensures consistent quality
Fully automated solution handling all phases
of preparation, welding and finishing
Examples of horizontal and vertical umbilical bundling machines
Mobile orbital welding set for spool interconnection Welding operation