FBE VS HDPE Coating

[nickypaliwal]

Assuming a condition where FBE and HDPE both can be applied for given temp., pressure, H2S, GOR, orientation, Service etc. How do we select between them ? Is it only the price and design life ?

Supposing a bulk header separator inlet and water/oil outlet piping. Which one of them would be preferred option ?

 

[LittleInch]

Is this for internal corrosion? HDPE usually suffers as a lining material from gas migration and diffusion causing issues on blowdown or reduction in pressure.

How you deal with welds, flanges and fitting is the big issue.

Which one? difficult to tell from your vague details, but if you've got gas or volatile components, check the diffusion rates.

For plant pipework this sort of thing is usually far too much bother / risk compared to using a material which doesn't need internal coating.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[weldstan]

Forget HDPE as a coating over carbon steel.

 

[SJones]

The question is driven by one of the OP's clients having a predilection for using either HDPE lining or internal FBE coating as corrosion control measures. You can note that the permeation and collapse issues have been covered by the reference to an 'acceptable' GOR (gas oil ratio). Constructing piping runs with PE lining does get tricky and requires an assessment of contructibility. It can be managed by, for example, rotolining of fittings or using corrosion resistant alloys for certain items, particularly where penetrations are required. Neither option really offers an optimal alternative to a fully resistant material selection, but the end user has entrenched beliefs and an erratic approach to lifecycle costing that results in multifarious and unpredictable corrosion control strategies. Given the more resilient nature of PE versus the FBE, in a given situation where both fulfil the end user's criteria, I would be more inclined to select the PE option as the opex of venting would be countered by the cost of inspection of the FBE coated pipe owing to its lower reliability.

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/pub/8/83b/b04

All answers are personal opinions only and are in no way connected with any employer.