FEATURES
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• Insert: the fitting is inserted inside the pipe, which is usually stretched to accommodate the fitting. The pipe then contracts back onto the fitting. This is sometimes re-enforced with an outer sleeve or collar;
• Compression: similar to standard compression fittings where an‘ O’ ring is compressed onto the outside of the pipe to form a seal; and
• Push-fit: a mechanical fitting where the action of pushing the pipe into a compatible fitting engages the fitting’ s sealing mechanism( usually an‘ O’ ring).
Use of these new systems is based on a wide range of advantages over traditional( predominantly copper) materials. And while there are applications where traditional materials might be preferred, generally the
Jointing method
Socket fusion welding
SANS / ISO
Pipe size( OD mm)
SANS 15874 16 – 125
Joint ring sealing SANS 1601, 8773
Crimp SANS 21003
40, 50, 110, 160
16, 20, 26, 32, 40, 50, 63, 75 following advantages point towards a polymer pipe system being the best choice:
• Improved flow characteristics, particularly over extended usage;
• Less heat loss;
• Greater noise absorption;
• Greater flexibility( depending on system);
• Lighter weight, therefore easier to transport;
• Less costly, therefore less prone to theft;
• Easy jointing methodologies are available;
• Fusion-jointed systems offer improved tolerance of vibration( for example compressed air lines, transport applications, and ship building); and
• No corrosion.
DOMINANCE If you look around at any new building project, chances are that you will see polymer piping as the material of choice for hot and cold water systems. It is now becoming more common in air conditioning, gas installations, and many other specialist applications and industrial processes.
With engineering polymers now able to withstand the most aggressive chemical conditions and temperatures well above boiling point and at ever-higher pressures, it is an inevitability that polymer piping systems will continue to be the dominant choice in the market.
Compression fittings
SANS 21003 15, 22, 28
You just have to be vigilant that the system you choose is correct for that specific application.
Push-fit
SANS 15876 done by AENOR
15, 22, 28
Pressure sleeve and fitting
Crimping
SABS 10508
SANS 21003-1- 2-3-5
16 – 20mm
16, 20, 25, 32, 40, 50, 63, 75
Fusion welding SANS 15874 20 – 160
Push-fit
Fusion welding
SANS 21003 Part 1, 2, 3 & 5
SANS 15874 / 2 / 3 / 5
Crimping ISO 21003 / 2 / 3 / 5
15 / 22 / 28
16 – 160
16, 20, 25, 26, 32, 40, 50, 63, 75
The use of hot and cold water polymer piping is dominant in timber frame construction, too. The flexibility of the pipes means they can easily be routed through the framework, while the sound-deadening advantages of polymer reduce water noise.
POLYMER PLASTIC PIPE AND FITTINGS GUIDE
• All known manufacturers / suppliers and distributors were sent a copy of Table 1 to provide the required information.( This has been updated by the participating companies themselves.)
• Polymer / multilayer pipe is for use IN BUILDINGS ONLY.
• DZR is a process of dezincifying the brass, making it stronger and more durable for potable water applications and is required by law.
• Unlike its plastic cousins PVC where fittings can be mixed, under no circumstances must polymer pipe fittings be mixed, as the jointing processes are different for certain pipes.
• SANS for polymer can now be tested by three accreditation bodies, namely SABS, SATAS, and AENOR. PA
www. plumbingafrica. co. za October 2017 Volume 23 I Number 8