PVC Specifications

PVC-U Pipe systems
Unplasticised poly vinyl chloride (PVC-U) is
one of the most widely used thermoplastic
materials for pipe installations. Being
odourless and tasteless it is suitable
for conveying potable water and many food
products. PVC-U has excellent chemical
resistance.

The good flow characteristics are the result
of the smooth bore and has good resistance
to abrasion. It is light in weight, easy to
join together making PVC-U a good alternative
to the more traditional materials.

PVC-U is resistant to most solutions of acids, alkalis, salts and solvents that can be mixed with water. Additional information in this respect can be obtained from our Technical Department.

Material
Tin stabilised compound conforming to the EEC safety levels for vinyl chloride momomer (VCM) and the WRAS requirements for use with potable water.

Colour
PVC-U products are recognised by their dark grey colour.

Chemical Resistance
The chemical resistance properties of PVC-U are excellent: it is resistant to most solutions of acids, alkalis and salts and to solvents that can be mixed with water. PVC-U is not resistant to aromatic and Chlorinated hydrocarbons.

WRAS Approval Water Regulations Advisory Scheme - approved product for potable water.
Standards Individual products are in compliance with appropriate British Standards. Kitemark Licence No. KM 60041 Fittings (inch size) BS 4346 Part 1 Pipe (inch size) BS 3505/6 Fittings (mm size) DIN 8063, ISO 727, KIWA 54, UNI 7442/75 Pipe (mm size) DIN 8061/2 Threaded fittings BS 21, DIN 2999, ISO7 Solvent Cement BS 4346 Part 3

Imperial and metric sizes
The following notes may be helpful to those unfamiliar with the different ways of describing metric and imperial sizes when specifying pipe or fittings. When specifying Imperial pipe fittings and other components reference is made to the nominal size of the pipe bore in inches and fractions of an inch. Metric Systems are specified by reference to the outside diameter of the pipe expressed in millimetres.

As a general guide the following table gives a comparison between metric and imperial sizes up to 8 inches. It is important to understand that metric sizes are not simply inch sizes which have been converted into millimetres and called metric. The actual equivalents are slightly different (except for Imperial size 2½ inches and metric size 75mm and 5 inches and 140mm which happen to coincide exactly) and are not interchangeable.

Temperature & Pressure Relationship

Pressure Ratings Fittings & Valves Imperial
Unless otherwise indicated the pressure ratings are as follow

All pressure ratings are at 20°C

Pressure Ratings Fittings & Valves Metric
Unless otherwise indicated the pressure ratings are as follows:

All pressure ratings are at 20°C

Thermal Expansion
The thermal coefficient of linear expansion for PVC-U is 7.8 x 10^-5/°C.
It is necessary in certain situations to make special provision for this expansion and contraction.
Thermal expansion of PVC-U is compared with other materials, in the following chart.