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Thread: PVC Conduit quality/ bending issues

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    PVC Conduit quality/ bending issues

    Is it just me or are others here experiencing issues with the quality of their pvc conduiting lately the last few years. Specifically bending and radius failures, kinking etc?. We utilise bundles of the stuff monthly and the last year has really been a nightmare in terms of wastage specifically the larger 25 and 32mm conduits that are hand bent with the appropriate springs , we are experiencing ridges in the conduit when bending, kinking and even deformation when doing simple 90's or even less critical 45s . With most of our piping being cast in slabs we simply cannot afford to take the risk of the less than ideal and inconsistent transitions and bends being cast into the slabs and coming back to haunt us weeks later when attemptng to pull in conductors . At first we thought it may be down to tired benders and that specific brand of conduit so bought new springs and a couple bundles from different manufacturers, we have found minor varying results amongst the different bundles some better than others however overall particulary the larger 25 and 32mm rough and poors bends and inconsistencies persist and mirror the same symptoms , the weird thing is you could bend the pipe with what would be considered an acceptable large radius and the pipe will still bulge or king on the internal corner yet in many cases cut the faulty bend out rebend it 300 or 400mm further down the same pipe and you could then achieve an acceptable bend but at this point its like playing Russian Roulette, Its so inconsistent our guys on site are loosing their minds and its wasting time and costing us money and efficiency..
    We did have one batch of conduit bought somewhere late Jan with no name or manufacturer marking on it that bent 100% perfectly each and everytime with the same spring benders but not knowing who makes it or where we got it at the time, I have no idea how we get it again, This makes me believe the chemical composition or quality of PVC being used by the majority of manufacturers now isn't correct or not suitable for the application at hand
    I read with interest other posts here regarding poor quality control of male adaptors couplings, varying od diameters of conduit, glands and other issues which we can relate to and our guys now diligently check before fitting or having to do their own qc on site before utilising but piping is now not something we can fine tune.

    Again are we alone here?.

    It's not like we are buying pipe at reduced pricing or reject stock, We are paying full trade price!

    Does anyone possibly know a smaller manufacturer or brand who is diligent in their piping QC and material quality?

    Weve never had any such issue in the 90s or early/mid 2000s whatsoever and the problems seems to have been more prominent from 2019 onwards, we cannot continue like this.
    Last edited by Tracsec; 08-Jul-24 at 09:04 PM. Reason: Ammendment to info below

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    I have not noticed problems lately but then have also not being do a lot of deck work- did have the problem 12 or 15 years ago and they blamed the springs
    We bought springs and conduit from same manufacturer which solved some of the problem - The story was that the internal diameter could be slightly different between manufactures and a spring from different manufacture would cause the kink

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    From experience ambient temperature can have a significant affect on the bend quality. I see you're in JHB and I can bet it's pretty damn chilly there this time of year, maybe try each type of counduit at a warmer temperature and see if it helps. I'm not sure how you could do this on site however so it's a bit of an academic exercise but I guess you could friction rub the conduit to warm it where the bend is going....
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    Quote Originally Posted by GCE View Post
    I have not noticed problems lately but then have also not being do a lot of deck work- did have the problem 12 or 15 years ago and they blamed the springs
    We bought springs and conduit from same manufacturer which solved some of the problem - The story was that the internal diameter could be slightly different between manufactures and a spring from different manufacture would cause the kink
    Thanks for the feedback. I think this is also part of the problem as wholesalers may just be sourcing springs one place, couplings and conduit another and bundling the stuff together. Whatever is cheapest and improves their bottom line , but it's been really difficult as everything pvc now lids, glands,springs etc have no identifiable manufacturer marks.

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    Quote Originally Posted by AndyD View Post
    From experience ambient temperature can have a significant affect on the bend quality. I see you're in JHB and I can bet it's pretty damn chilly there this time of year, maybe try each type of counduit at a warmer temperature and see if it helps. I'm not sure how you could do this on site however so it's a bit of an academic exercise but I guess you could friction rub the conduit to warm it where the bend is going....
    Appreciate the thoughts here, yes we are in JHB,on cold days here we do have a portable blowtorch with cylinder to do this direct on the deck and warm the materials which helps but the main buldging or ridging on the internal corners remains. Significan enough to be an issue when sending fischer in thrm to be a nuisance. Out of interest I did some digging on the issue internationally and in the States whilst they mainly use EMT I did find some info on very similiar issues we are experiencing . And having listed the multitude of possible causes you guys have mentioned springs temps etc there was also note that the material charecterist may be deficient in nature in its maleability to bend correctly even using the correct tools. I fear we possibly have more than one issue here.
    I'm not a chemist but honestly we shouldnt have to be stuffing around like this on site. It's hard enough as it is and we are paying good money for materials. Is it too hard to expect somewhat of a simple functional product that will bend properly rather than having to resort to pre fabricated bends in critical lines ,

    We are using a very large national wholesaler so I would expect the problem is being experienced by other contractors too who I am hoping possibly see this thread and can shed lighton their experiences as we cannot be the only one.

    It would appear the minute the product is out the door and paid for no one is interested afterwards as we have tried to raise the issue but everyone is shrugging their shoulders.

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    Yeah I had this same problem last year.
    In my case the pipe would just explode when you start the bend.
    So frustrating and a waste of time and money.
    However this year it's been okay. Back to normal.
    Based in Southern Cape.

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