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The PETROSLEEVE® repairs
defects such as Seam or Pipe Body Cracking, Corrosion, Dents, Mechanical
Defects,
SCC (Stress Corrosion
Cracking), and Arc Burns. Although the failure mechanism varies
for each defect type, the following is a good outline description
of various defects
and how
the installation
of a PETROSLEEVE® permanently
removes the failure mechanism of the defect.
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Corrosion:

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Corrosion defects are caused by a chemical reduction action on
the surface of the pipe material, resulting in
localized thinning of the pipe wall. Failure occurs first by bulging
(yielding) at the corrosion site, followed by rupture of the
steel
membrane.
The installation of a PETROSLEEVE® provides mechanical support
to the localized thinned section. It is this support
that prevents bulging for all pressures, including during high
pressure testing.
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Gouge, Groove:

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or Arc Burns:

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These defects are caused by either third-party damage or
non-acceptable workmanship, and may include stress concentrators
such
as
cracking. Failure occurs by the pipe material containing the defect
flexing because of internal pressure variances, which in turn causes
cracking. When the crack extensions become critical, rupture occurs.
The installation of a PETROSLEEVE® eliminates
flexing in the pipe material and the stress state in the material
surrounding
the defect is put into compression, eliminating fatigue, crack extension,
and rupture. |
Dent:
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Dent defects are caused by either third party damage or non-acceptable
workmanship. As in the gouge, groove or arc burn cases, failure
occurs
by the pipe material containing the defect flexing because of internal
pressure variances, which in turn causes cracking. When the crack
extensions become critical, rupture occurs.
The installation of a PETROSLEEVE® eliminates
flexing in the pipe material and places the pipe material into compression,
eliminating fatigue, crack extension, and rupture. |
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Pipe Body Crack:

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Pipe Body Cracking is caused by various means, including chemical
action (Stress Corrosion Cracking). Failure occurs when crack
becomes unstable.
The installation of a PETROSLEEVE® permanently
reduces the stress state in the material surrounding the defect,
removing the possibility for crack extension. |
Weld Defect:
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Weld defects are caused by poor workmanship. Failure occurs
when the strength of the weld is not sufficient to counteract the
applied forces.
The installation of a PETROSLEEVE® permanently reduces the stress
state in the material surrounding the defect, as well as providing
support to the weld.
The PETROSLEEVE® provides permanent mechanical support to the
weld area and reduces the strain induced in the weld by the external
forces. |
Grind
Defect:

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A grind defect is caused by mechanically removing metal from
the surface of the pipe material, resulting in localized thinning
of the pipe wall. In addition, stress concentrators could be present
on the metal surface. Failure occurs first by bulging (yielding)
at
the grinding area, followed by rupture of the steel membrane. Additionally,
the presence of stress concentrators could act as initiation points
for
rupture at lower strain levels.
The installation of a PETROSLEEVE® prevents
bulging by permanently providing mechanical support to the localized
thinned section.
The sleeve
also eliminates metal movement (fatigue), and reduces the strain
induced in the material by the external forces. |
Leaking/Through-wall Defect

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A leak occurs when a hole in the pipe wall allows the liquid
or pipeline product (i.e. oil or gas) to escape, while the pipe
wall continues to contain the internal pressure preventing a rupture
from occurring. Both
leaking defects and active internal corrosion will proceed through
the the wall of the pipeline if left unrepaired.

At present, development is underway to research and
test a unique technique using the PETROSLEEVE® Repair
System to repair both leaking defects and active internal corrosion.
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All rights reserved.
Reproduction in whole or in part in any form or medium without the express
written permission of PETROSLEEVE Inc. is prohibited. design:swur.com |
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