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Qualification of GRE manufacturer

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uaepiping

Mechanical
Feb 3, 2013
106
Dear Piping engineers,
The main question here is how to qualify a GRE manufacture to be on the approved manufacturers list of the company?
In Iso 14692 - 2, Chapter 6 qualification of the manufacturer is given. It is mainly related to manufacturing part only (which seems fair enough). But the problem starts when there are three parties involved in the design, manufacture and installation of the GRE piping system:
Yes obviously:
1 - Designer (Layout and stress analysis engineers),
2 - Manufacturer of GRE piping materials and fittings,
3 - Construction contractor who installs the GRE piping system at site.
The lack of understanding of the problems of each other gives raise to the trouble of failure in GRE piping system later on (mainly joints).
How to ensure a trouble (failure) free GRE system?

Is it worth to make single source (mainly manufacturer) responsible for all these phases i.e. design, manufacture and installation? Should we include all these factors in qualifying the manufacturer? And how to include these factors in qualifying checklist?
So what is your opinion about it?
 
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Part 2, Clause 6 is for PRODUCT qualification, as opposed to MANUFACTURER qualification. The former would be considered as a subset of the latter. Interfaces in the design, procurement and installation chain are always potential quality weak points. Dependent upon contractual arrangements, it may not be possible to bundle all three activities under a single responsible second party, and this is an optional arrangement that would need to be investigated as part of the appraisal process for the three activities, i.e. incorporated in the "checklist."

"How to ensure a trouble (failure) free GRE system?":

Demonstrated experience, demonstrated experience and demonstrated experience.

That maxim goes for both the end user, the purchaser if different, and the suppliers. It also contextual, i.e. demonstrated experience with an above ground 4 inch low pressure piping system for water is not valid for a buried 16-inch high pressure hydrocarbon pipeline. The project cannot be used as a training and development exercise by any of the parties involved which means that qualification documentation, prior project endorsements of the parties working together, and personnel competency verification is very important, especially construction staff.

Steve Jones
Corrosion Management Consultant


All answers are personal opinions only and are in no way connected with any employer.
 
I would recommend that you look at the major manufacturers in your region(UAE?)and add them to your approved vendors list if they meet your criteria. As well as manufacturing capabilities they should be capable of carrying out stress analysis of underground systems from your supplied routing and if required be able to supply UL/FM for firewater systems. As part of purchase order they will be able to supply supervision to the contractor for installation.
 
I've done a reasonable amount of GRE design etc and my recommendation is that you choose your vendor carefully and then get him involved and responsible for many of the aspects you list.

So the routing and sizing etc is part of the designer, but then make the vendor do the stress analysis and provide a report to be checked and reviewed.

Vendor then makes all the pipe, does whatever pre-tests you want and can advise at the least on what type of joint you want.

Then even if you choose and pay for the installation contractor, employ the vendor in a QA/QC and installation supervision role to monitor, check and sign off on all joints and installation / tests. You will need to back them up if they want joints re-done or installation different to what the contactor wants.

Of course this isn't cheap as often the on site personnel are ex-pat personnel with rotation of personnel if its a long system, but then you have a clear path of responsibility for final design check (stress analysis), manufacture and installation in one company.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
Thanks for your inputs!
In our COMPANY specification, we have given clearly that manufacturer of the GRE pipes and fittings shall be responsible for design, stress analysis, support design, FE analysis (if needed), manufacturing and installation (or supervision during installation)!
BUT,
Even then we are having troubles with failure of GRE joints. Yes mainly joints!
Littleinch as you have pointed it rightly, the cause lies somewhere in the quality checks carried out at each joint making. For steel piping we have sufficient things to ensure this:
WPS, PQR, welders qualification and then weld records right from the pre-heat temperature of the parent metal (and electrodes) as well, bevel edge preparation, type of bevel, root pass, interpass temperatures, multiple passes, postweld heat treatment, hardness check to verify the PWHT, Radiography. All these are recorded and record and history of each weld joint is available even at later stages.
But what about GRE joints, what checks are there to ensure that a joint is made as per design requirements and will sustain the design conditions for its design life? We are looking for this as well.
Any view to share on this (QC of Joints and laying of GRE piping)?
 
Most GRE manufacturers have installation procedure detailing backfill, joint preparation etc but unfortunately the quality of personnel doing installation is not always as required as you tend to get what you pay for. Take a look at attached Ameron Installation Guide for some pointers.
 
 http://files.engineering.com/getfile.aspx?folder=1450b4f6-11ef-4215-ab9a-7a70f3ac7250&file=AMERON_20-_20Instllation_20Guide_20For_20GRE_20Pipe_20Systems.pdf
@MickMc,
Yes, we normally get disappointment and definitely do not get the value for money. Company may pay more for the reliable working of the piping system as the cost of the failure later on is heavy so evaluating on that basis is fruitful.
@sjones,
Frankly we do not directly qualify the fitters, supervisors and inspectors, we award the project to EPC. And there lies the problem as designers is different, manufacturer is different and construction team is altogether different.
 
Therein lies the issue about many of the non metallic piping systems.

In the end your QA/QC is only as good as the inspector monitoring the installation and the training and experience of the jointing crews. I've heard companies in ME complaining that they send their technicians on a 3 week training course in Europe and then they jump ship and earn more money at their competitors, so are then very reluctant to train any more. Hence the client may need to stump up the costs fro training....

There are ways to pressure test each joint as you go along, things like this are claimed to be applicable to GRE
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
It seems to me that your problem is not with design and manufacturing but with installation by contractor. Typically you will award the EPC to a particular contractor who will handle EP and subcontract the Construction to a local contractor who will supply welders, fitters etc and in ME the quality may be lacking, no formal training etc. My only suggestion is to focus on supervision of jointing by GRE vendor reps which may mean increasing their involvement.

I would add that I am not usually involved in the construction side but feedback from colleagues typifies your experiences in ME and that my current operator has reverted from GRE to cement lined CS for FW systems due to faulty workmanship and subsequent leaks.
 
Thanks friends,
Summing it up it seems that we should:
1) Qualify the manufacturers with capability of design (perform stress analysis, surge analysis, FEA, support design, preparation of layouts (routing)); capability of manufacturing GRE Piping materials (Naturally) as per applicable standards; capability of testing in-hose the quality of manufactured items as per applicable standard; Capability to install or supervise the installation of GRE piping system. Meaning a single source of responsibility.
2) It has to be ensured by GRE manufacturer that quality of making of joints is as per requirements of design (surge loads, stresses) and other factors to ensure joint integrity are properly take care of such as compaction of soil.
3) To supervise all this we must train our own COMPANY's quality control personnel to be aware of the GRE piping systems - how to evaluate/judge/inspect/witness the laying of GRE piping and joint making up to backfilling & compaction and hence assure the quality of joint as per design requirements.
.
Am I missing something?
 
@MickMc,
In our COMPANY GRE vs metallic piping is already being investigated. The pros and cons are being checked.
Waiting for this study to finish with outcome.
 
I think you are maybe looking for too much from the GRE vendor regarding design.

1) IMHO his product has to be qualified and his capability of undertaking stress analysis of system layout provided by your EPC contractor which he will make recommendations on for flexibility and support. The extent of site supervision by vendor to be specified by client and/or contractor but my advice would be to stipulate pre EPC award your requirements to allow it to be properly costed.
2) Again in my experience this is contractors responsibility with help from vendor reps, I doubt they would contractually take any direct responsibility as typically they will only supply supervisory consultation but I may be wrong.
3)Agreed.
 
I think your post above just about covers it.

Don't forget the transport and handling issues. GRE pipe is notorious for getting damaged (bruised is a good word to use) easily, but not exhibiting this damage until a few months / years later.

Having looked at GRE systems and been involved in installation and repair. I've come to the conclusion it's more trouble than it's worth for buried pipeline systems. Above ground, working in nice neat angles, no stones rubbing holes in it, no hairy arsed pipeline contractors throwing it around like it's steel, then it's great. Below ground, try and use something else.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
@Littleinch,
Thanks.

@MickMC,
Yes this is opinion amongst our piping team as well that we may be asking too much from GRE manufacturer. But we do not want to miss anything as well. Maybe vendor qualification group (or vendor themselves) would revert back to us for this.
[smile]
 
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