010 447 3635 [email protected]

Polyvinylchloride plastic pipe, commonly known as PVC pipe, comes in various categories each with specific applications. PVC pipe can be broadly categorized into pressure pipe, underground pipe (sewer pipe), soil and vent pipe and flood pipe (also referred to as cable or duct pipe). These categories are easily distinguishable by their colour; with pressure pipe being blue, underground pipe being cream, soil and vent pipe being white and flood pipe being a very dark blue or black.

Pressure Pipe Sewer Pipe Soil & Vent Pipe Flood Pipe

We at The Watershed fabricate PVC fittings from all of the above categories of pipe. 

Pressure Pipe

Sizes: 50mm, 63mm, 75mm, 90mm, 110mm, 125mm, 140mm, 160mm, 200mm, 250mm, 315mm, 355mm, 400mm, 450mm, 500mm, 630mm

Pressure pipe is classed according to its pressure rating with classes; 4, 6, 9, 12, 16 and 20 denoting the amount of pressure in bar that the pipe can withstand.

Both Unplasticised PVC (uPVC) and Modified PVC (mPVC) can be used to extrude PVC pressure pipe. mPVC is more ductile and has a higher toughness than uPVC, and therefore can get away with a lower safety factor than uPVC. This reduction in the safety factor allows mPVC pipe to have a thinner wall thickness for a given pressure rating; making mPVC pipe approximately 35% lighter and hence cheaper than the equivalent uPVC Pipe.

uPVC isn’t softened by plasticisers and therefore is more durable compared to mPVC. uPVC’s thicker wall also makes fabrication more precise.

There is a third type of pressure pipe, namely Bi-axially Orientated PVC pressure pipe (oPVC). Unfortunately fittings cannot be fabricated from oPVC because oPVC shrinks and deforms when heated.

We at The Watershed prefer using uPVC pipe to make pressure fittings, we will however fabricate from mPVC pipe on request. You can find our Price List for uPVC fittings here.