INGENIEUR
INGENIEUR
Mechanical Clamp Composite Wrap Grout Filled Sleeve
Source : Reference 4 Source : Reference 5 Source : Reference 6
Leak Containment solution . It can also be Material Strengthening if the clamp cavity is filled-up with an epoxy-like substance .
Material Strengthening and Leak Containment . Flexible approach as the wrap can take the shape of the pipeline together with the dent profile .
The diameter of the sleeve is larger than the pipeline with the gap filled with an epoxylike substance for Material Strengthening purposes .
Remarks : a . Mechanical Clamp can be designed for Pressure Leak Test after installation depending on stakeholder requirement . b . Sometimes “ Grout Filled Sleeve ” can be designed for leak containment , based on Contractor ability and
Stakeholder requirement . c . For mitigation purposes , technical personnel may refer to ASME B31.4 ( 2019 ) Clause 451.6 “ Pipeline Integrity Assessments and Repairs ” or ASME B31.8 ( 2018 ) Clause 851.4 “ Repair Procedure for Steel Pipeline ” to determine the industrial recommended repair method . d . Some Industrial Codes do have restrictions on wrap . For instance , ASME B31.8-2018 Clause 851.4.2 does not accept non-metallic composite wrap repairs on injurious dents or mechanical damage unless proven through reliable engineering tests and analysis . e . On some occasions , Mechanical Clamp or Grout Filled Sleeve can be placed on top of a composite wrap , meaning 2 mitigations in place . f . The so-call Material Strengthening theory works by transferring the stress from the pipeline body to the clamp / wrap / sleeve provided there is proper surface contact and a well-distributed compression medium such as epoxy exists in between the materials . g . Some Industrial Codes mention dents that exceed 6 % of the nominal pipe diameter are considered injurious and require examination , such as ASME B31.4 ( 2019 ) Clause 451.6.2.4 ( d ) and ASME B31.8 ( 2018 ) Clause 851.4.1 ( d ). However , it depends on pipeline owner ’ s discretion .
Table 4 : Typical Subsea Pipeline Repair for relatively mild Mechanical Damage
underwater Non-Destructive Examination ( NDE ) methods on both external surfaces ( e . g . Visual Inspection , Magnetic Particle Inspection , Alternating Current Field Measurement ) and internal segments ( e . g . Single Probe Ultrasonic Testing or Phase Array Ultrasonic Testing ). Additionally , outer dent profiles can be measured for FEA confirmation .
After securing the damaged section and examination , the professional member can then prescribe the appropriate action to be taken on the damaged section . There are different ways to mitigate a Mechanical Damaged pipeline with the
intention of Material Strengthening ( prevent leak ) and / or Leak Containment , for example , “ Clamp ”, “ Wrap ”, and “ Sleeve ”, with each having their own unique properties on leak mitigation . Pipeline Clamp has tighter dimensional tolerance to attain proper sealing mechanism , and therefore there is a need to confirm measurement upfront . Alternatively , if the pipeline damage is severe , the owner can opt for “ Sectional Replacement ” whereby the affected portion is cut out and replaced .
In some cases , the removal of subsea pipeline defects via grinding or de-burring may be permissible provided there are engineering
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