Plastic pipe

[Bernie2]

I've used loads of plastic and for certain jobs I like it.

But whilst I have used it for water supply and central heating, I am always a bit suspicious of it's use in these areas.

I have seen it "blow" a joint for no apparently obvious reason. I also know it goes like skipping rope in normal use when heated, and miles away from the boiler.

But some articles I read, apparently say there is some doubt about its high and low temperature performance over extended periods of time. Its said it goes brittle.

Its also well known that it entrains air and possibly might pick up some other chemicals. That is beside making the water taste.
It can also melt in contact with other hydro carbons as well as expand like mad.

So beside its faults and ease of fitting, what else is there about it that makes it a good buy?

If you use it, have you seen systems that have used it, more than say fifteen, twenty or thirty years old on central heating systems?

If so what condition was the pipe in?

Also how has the blue MDPE stood up over longish periods?.

With oil prices rising will we continue with its use, if copper becomes cheaper? 🙂🙂🙂🙂

 

[Plouasne]

Wiki, has a few comments on PEX tubing Cross-linked polyethylene - Wikipedia, the free encyclopedia, personally speaking the persons who invented plastics for plumbing should be boiled preferably alive in their inventions, I detest the stuff

 

[Bernie2]

Yes I prefer copper as well Plouasne.

I was just trying to get some idea of the long term problems with plastic water piping. Although I've put it in, I have never been back to the jobs after a few years to find out.

Another point about plastic, is there a rodent problem?

I was doing some work in pub once, and the guy was telling us about the mice eating through the beer pipes all the time.

I wonder if it has happened with PEX or any of the other plastics in domestic situations, mind you the pub pipes where nylon.

 

[Plouasne]

Mice, rats and other rodents chew through pvc cable and see no reason why they should not chew through other plastic's, providing that they can get their mouth around the pipe, and its not too big to chew on


I have been out to repair old poly water mains where it has rubbed on a sharp stone or other hard sharp object in the ground, that's why I advocate a continuous outer plastic sleeve for water mains now, another thing I found in France, that was standard practice there but not in the UK

 

[Bob Croft]

I have seen joints come apart on PEX systems but not for unexplained reasons, they have always been incorrectly assembled. I have not seen the pipe expand significantly or go brittle. The Hepworth pipe carries a 50 year guarantee but the longest installation I can personally comment on is 10 years old with no problems so far. It is my understanding that barrier pipe does not allow air or other gases to enter the water within. The pipe does go soft when hot even if clipped at 250 -300 mm centres and thus sags. My preference is to use copper but there are times, like under floors where plastic can be installed with less fuss and less upheaval to the customers property. I have been told that on most new build sites the houses are completely plumbed in plastic except for a mere or two from the CHB and the gas supply.

 

[Bernie2]

Hi! Bob.

Does seem to be a problem over the joints, the complaints of "Blow off" are just to many.
Okay fair enough joints may have problems if they are not seated right. The problem is, if as seems likely, so many people seem to seat them wrong. Then isn't the joint too complicated or poorly designed?

As you know a lot seems to depend on the grab ring grabbing the pipe.

If the back nut is not tight, it seems the grab rings still seem to grab the pipe, and kid you on its holding. Its a point easily missed on a busy site.

 

[heinz57]

I can see that people complain about plastic pipe but interestingly enough the sales
of plastic pipe are on the increase every year, but like Bernie says it would be nice
to see some long term studies done on these pipes and the results published.

 

[Plouasne]

"Hepworth", that company has done more to lower the skills of the plumbing industry, to a mickey mouse set up, than any other company, in my opinion, with its waterless traps, push fit plastic water pipe, plus that "Vache" thatcher who was the death knell for proper trade training

 

[traineedrip]

Hi! Bob.

Does seem to be a problem over the joints, the complaints of "Blow off" are just to many.
Okay fair enough joints may have problems if they are not seated right. The problem is, if as seems likely, so many people seem to seat them wrong. Then isn't the joint too complicated or poorly designed?

As you know a lot seems to depend on the grab ring grabbing the pipe.

If the back nut is not tight, it seems the grab rings still seem to grab the pipe, and kid you on its holding. Its a point easily missed on a bust site.

The very nature of the fittings is speed. Only the other day i was riddiculed for using my thumb as a guide making sure it was "in".
Easy to get caught out as theres no skill involved so little pride taken.

How long has plastic been out now?
Interesting comment about rodent attack, Plumber i know always uses it where its out of sight. Pretty much where the rodents are going to be if they take up residence😀

 

[dontknowitall]

I think plastic plumbing has been around for 50 years or so!!

 

[Plouasne]

I think plastic plumbing has been around for 50 years or so!!

The first time I C I (remember them?) brought out black poly water pipe was around 1958, and if my memory servers me right the BS number was BS1972, sockets and other fittings were also made of poly, and had a crude form of electro fusion in the fittings socket, in the form of a wire spiral, with two tags of wire exposed at the mouth of the socket, a 12v car battery was the form of electrical power, to use the only instructions were when molten plastic is seen at the fittings mouth it is done

Marley brought out some of the first soil pipe and fittings in the early '60's, and what krap they were, anybody old enough to remember, how you placed a rubber ring on the w/c pan outlet, pushed pan with ring still in place, in to a deep socket, then with a blowlamp (none of your fancy gas torches then), heat the socket up so that it would contract over the "O" ring on the pan outlet, and hopefully be water tight, other wise it would be red lead putty being thumbed into the gap between pan outlet and plastic socket

 

[Bernie2]

Hi! Plouasne

Yes I remember those shrink on adaptors. Some times they worked sometimes they did not. But its amazing how quick plastic use, became wide spread isn't it?

I was reading about, how in the states they blame plastic for making the water taste different. I also know that some say chemicals can leach into the water, through the walls of the pipe.

I don't know what the UK will do if there is a problem with plastic used as water main, it seems nearly the whole country is now supplied by mains water from plastic pipes.

I haven't really read any reports on the use of plastic pipe for water mains in the UK, other than the usual sales brochures that tell you its good stuff.

In the states for instance PEX pipe has been the subject of a class action which the makers lost.

Apparently it went porous and leaked all over the place.

I wonder who in the UK is responsible for testing this stuff?

After all water is a food stuff, and it should be proven fit for human consumption.
I assume it is of course, but just haven't seen any reports about on chemical leaching both out of the ground around the pipes and out of the pipe materials themselves.

I know Greenpeace don't like PVC plants and put a lot out about their pollution. So if the chemicals they use to make the stuff causes pollution, what about the stuff itself.

Don't get me wrong I assume its perfectly okay, its just that I could not point to any independent report that would confirm that.

 

[Plouasne]

bernie,

Remember way back in the '60's - early '70's when poly was not allowed if there was a gas main near by ?? because of the possibility of gas permeation, and contaminating the water, its all gone leave it to the scientist now, they know best, when in actual fact they know b**ger all when it comes to the practical side

 

[TGor]

In the states for instance PEX pipe has been the subject of a class action which the makers lost.

There was also a big hoo ha about polybutylene so much so that it has not been sold in the US for years. US water has a lot more chlorine and this appears to have been the major problem. New requirements for plastic pipe to withstand high levels of chlorine have now been imposed.

I wonder who in the UK is responsible for testing this stuff?

After all water is a food stuff, and it should be proven fit for human consumption.

I assume it is of course, but just haven't seen any reports about on chemical leaching both out of the ground around the pipes and out of the pipe materials themselves.

You are quite right .. there are many international standards for the toxicity limits of materials in contact with potable water both metals and plastics, the UK is BS6920 testing done by WRAS (WRC) & Water Quality centre among others. also the Drinking Water Inspectorate (DWI regulation 31) some of these requirements are very stringent with long and complicated test procedures as it should be. The performance of plastic pipe installations is also covered with frequent required checks on material quality and performance. The US and Australia particularly have a well implemented surveillance system where factories that produce plastic pipes are inspected regularly for compliance to the appropriate standards the US inspects such factories at least 3 times each year. The UK does not appear to have such stringent controls with only "type testing" for initial compliance ongoing testing may be required but I am not sure how often.

The major manufacturers of plastic pipes do take quality control very seriously with high levels of internal inspection as well as external audits .. I know of one manufacturer that has over 70 external auditors visit each year.

The majority of failures in the field are, I am afraid due to installer errors and this is why the major manufacurers invest heavily in training installers.

rgds
TG

 

[justlead1]

Hi, I have been involved in the plumbing trade for the best part of the 50 years mentioned, and can confirm alkathene pipe for underground services was available, other than that copper pipe to BS 659 was the material along with cast iron and gas carcass was black iron screwed. As a result of the copper crisis in the late 60,s the standards changed. Thin wall copper tube and micro bore were introduced to the trade. Causing major debate within the trade. As a massive domestic market was emerging, company's were quick to see the potential making some thing for 5p which were selling in copper or brass for £5. This encouraged research and development of plastics, which has changed practical plumbing beyond belief. Those young plumbers who express the love of their work would have be ecstatic. Carrying out work that was unique to plumbers, earning a few quid and getting an audience when demonstrating some of the skills. Coupled with instant cash for scrap when you done your money in the betting shop or pub. Halcyon days http://www.ukplumbersforums.co.uk/members/dontknowitall.html

 

[Bernie2]

In the States and Canada they may very well check plastic against their water for cross contamination.

But do we?

Drinking water is not a pure substance, there are all kinds of complex compounds in it, and whilst over time we may have become aware of how those compounds react with the likes of lead and copper which have been in use for hundreds of years.
Can we really say we know what happens to those and other modern chemical compounds found in our water, as to their effect when inside plastic pipe systems?
Certainly many web sites report leaching from PVC.

And considering how many people drink water every day shouldn't we be trying to find out, and publishing the results?

It seems to me that new plastics are invented on a Monday and used on a Tuesday without much long term research into their effects on the water supply.

I know its a very handy and versatile material and one I feel has got its uses.

For instance I can't see as it would do any harm in a sealed central heating system, at least nobody is going to drink the water.

But in domestic potable water supplies? Hmm! I have my doubts.

Rainwater gutters and drains?
Possible problems as they are connected to the environment through discharge points into rivers and local water courses.

I remember one time a pollution problem happening in my area, and when asked why it had happened. The authority basically replied "The pollutant got through the system so quick we had no time to do anything about it!"

Now if one chemical can get through the system, what if a plastic reactive chemical got into the system?

At least you know what is likely to cause a reaction with copper, we have been using it for thousands of years, but some people have probably got a shirt older than some plastics.

Once again don't get me wrong I assume its all okay, the manufacturers are responsible people. Its just that the public should perhaps know a bit more and the Water Research Council be a bit more active.
　

 

[Plouasne]

Bernie,

Have a look at the pictures in the link, click on to them and see the ones I have used and prefer, these are the ones that have a serrated insert and an outer sleeve that has to be drawn up over the insert (a dammed hard job when the plastic is cold in winter) which compresses the plastic wall of the pipe into the serrations of the insert

Plomberie PER, Multicouche, laiton, cuivre, PE, tube per, chauffage, collecteur, sanitaire - Vente en ligne de fourniture de plomberie : raccords per, raccords cuivre, raccords laiton, raccord multicouche, collecteur, robinet, joint, accessoires, rou