Pipeline Leakage Repair FAQs

1. Drawings?

amex-10-end-seal-cross-section-v3-2016 Two drawings, a 2D dimensioned cross-section and a 3D blown diagram: AMEX-10 2D Cross Section AMEX-10 3D Blown Diagram

2. What surface preparation is needed?

This depends on the pipe material. For the very best results, the seal should be installed directly to the pipe wall; if the pipe is coated ideally this should first be removed. If the pipe coatings cannot be removed, then the integrity of the seal may be compromised because there is a potential leak path behind the coating.  After fitting, any removed coatings can be replaced with an appropriate paint or screed. If the pipe material is steel or iron, then a suitable anticorrosive system will be agreed before the contract commences. If the pipeline carries potable water, then the replacement protective coating must be approved under Regulation 31(4)(a).  The number of  coatings approved under this regulation is rapidly diminishing, therefore, this must be discussed and agreed well in advance.

3. Are your men trained for Confined Space?

Yes. All our site operatives, foremen, supervisors, surveyors, engineers and managers are trained, experienced and competent in:
  • City & Guilds 6150-03 Working in High Risk Confined Spaces
  • City & Guilds 6150-05 Rescue from Confined Spaces
  • Emergency First Aid at Work - all Operatives
  • First Aid at Work - Foremen, Supervisors, Surveyors, Engineers and Managers
  • AED - Automated External Defibrillation
  • OVR - Oxygen Ventilator Resuscitation
  • Trauma Technician

4. What's the maximum pipeline pressure?

As part of the WRAS product approval, the AMEX-10 seals are tested to 45 bar, therefore, have an operational working pressure of 22.5 bar.  However, PMP have successfully installed seals in pipelines which were pressure tested at 40 bar.

5. What sizes are the seals?

The AMEX-10 seals are made to measure.  Wherever possible, before ordering the seals, we recommend PMP carry out a man entry inspection to see the joints first hand and to measure the internal pipe diameter at the joint locations to ensure the right size seals are ordered.  Nominal bore pipeline dimensions will not be sufficient.

6. What's the largest seal you've installed?

3650mm Ø seals in a power station cooling water pipe.

7. What's the smallest seal you've installed?

The AMEX-10 seal is a man entry repair method therefore it is not designed to be installed remotely.  A specific exception is where the failed joint is the first joint in from a man accessible chamber.  The smallest seal installed by PMP is 550mm Ø.

8. How are the seals installed?

The AMEX-10 seals are installed by our trained and experienced fitters.  The EPDM rubber seal is compressed against the pipe wall by expanding 2 stainless steel retaining bands with a hydraulic jack.  No chemical adhesives are used. The 2 retaining bands seal the rubber from pipe to pipe, leaving the rubber between the 2 bands free to span the pipe joint, allowing the joint to move.

9. How are the seals tested?

After fitting, the seals can be individually tested by connecting a portable air tester to inflate the seals with compressed air.  Once inflated, a soapy solution is applied around the interface between the seal rubber and the pipe wall to check for leaks.  Since air is very much more searching than water, a pneumatic test provides an extremely reliable indicator of the success of the repair.

10. What seal widths are available?

We first need to agree our terminology.  The EPDM rubber of the AMEX-10 seal is manufactured in a continuous extrusion process which is cut to length and seam welded to form a hoop with an external diameter equal to the internal diameter of the pipe; hence the need for the survey.  The width of the seal therefore means the length along pipeline. The AMEX-10 seal is available in three sizes: STANDARD - 260mm wide MEDIUM - 366mm wide EXTRA WIDE - 540mm wide

11. How tough are the seals?

The EPDM rubber which spans the pipe joint is approx. 5mm thick.  EPDM rubber is extremely tough and durable, offering far superior resistance to puncture or abrasion.

12. What guarantee is given?

The seal has undergone an exhaustive test carried out by RAPRA, the leading rubber testing centre, which successfully demonstrated the AMEX-10 seal will last in excess of 50 years.  No other pipe joint repair system has undergone this meticulous testing.  We are therefore able to offer a life expectancy of 50 years.

13. Can the seals tolerate joint movement?

Yes.  Because the seal is installed independently on either side of a pipeline joint, the rubber spanning across the joint is free to move with any subsequent pipeline movement.  The seals can accommodate expansion, contraction, displacement or rotation.  If the pipeline movement is excessive, possibly due to land slippage, then PMP can return to the seals to release the stainless steel retaining bands, reposition the rubber and re-expand the retaining bands.

14. Can the seals tolerate stepped joints?

Yes.  The rubber of the seal spans freely across the joint and is only fixed to the pipe walls on either side of the joint.

15. Can the seals be installed to 2 different pipe materials?

Yes. The seal can be installed to pipe joints having 2 different materials, so long as the seal can be installed to the pipe walls on either side of the joint.

16. Can the seals be installed to 2 different pipe diameters?

Yes.  By increasing the size of one of the two the steel retaining bands, 2 different pipe diameters can be accommodated.  This is not straight forward and takes much longer, but it can be done; within limits.  This must be discussed in detail prior to order.

17. Can the seals repair pipe cracks?

Yes. AMEX-10 MONO is designed to repair leaking pipe joints and radial cracks. AMEX-10 VARIO is designed to be linked together to span over longitudinal cracks.

18. Can the seals withstand ground water infiltration?

Yes.  The seal can withstand infiltration of surrounding ground water but, since this may have the effect of inflating the seal, it must be restrained from ballooning by adding additional stainless steel bands.

19. How much does the seal intrude into the pipe?

The AMEX-10 seal is a low profile seal.  The EPDM rubber is approx. 12mm thick at its leading and trailing edges. Before installing, the stainless steel retaining bands appear raised but these compress to the same height when fully loaded.

20. What's the delivery period?

Since the seals are made to order in Germany, we are constrained by the supplier's manufacturing programme and their delivery.   This can be up to 2 weeks from your written order but is often very much less; the quickest has been just 4 days.  Occasionally, we may have some common sizes in stock, but these can only be used if they match the internal diameter of your pipeline.

21. How far will you travel?

PMP's agency with Amex GmbH is for the 'supply & installation' of AMEX-10 seals in the UK and Ireland, however, we have travelled the globe to solve problems far and wide.  PMP have installed AMEX-10 seals in:
  • Northern Argentina, cooling water pipeline of a new gas fired power station
  • Hong Kong, sea water intake
  • Puerto Rico, sea outfall, underwater, installed by divers, supervised by CCTV