Flexibility
P.V.C.u. pipes and fittings are regarded as flexible under the stresses set up by backfill and surcharge loads. Properly installed in a suitable bed and surround, part of this load is transmitted to the side fill, which is correspondingly consolidated.
The modulus of elasticity of P.V.C. u. varies from about 400,000 p.s.i. when new to about 200,000 p.s.i. After 50 years.
In the event of unforeseen excess loading which could cause fracture of pipes of rigid materials, the P.V.C. u. pipes merely take on a small, and generally temporary, increase in deformation.
Precision Manufacture
The P.V.C. u. system has been based on the past usage and experience with pressure pipe for gravity purposes. Sewerdrain joints are made with the same precision as pressure pipe joints. This means that correctly installed, infiltration is eliminated and there is no need to allow for it in design.
Connections at a later date can be done with equal confidence.
Precision joints together with longer pipe lengths reduce the risks of blockage and have a minimal effect on flow.
Light Weight
Handling costs reduced to a minimum. Easily stored, easily laid with fewer men and less machinery.
Ruggedness
P.V.C.u. can reduce breakage dramatically because of its higher impact strength. Even pipes which have suffered some damage can be partially saved by removing the damaged section.
Corrosion Resistance
Normal acid or alkali soil conditions have no adverse effect. Sewerdrain can be used for a wide range of industrial effluents. For more detailed information contact our technical department or consult BS code of practice CP.31 2, Part 1 :l 973.
Easily Worked
No special tools required and not unkind to the hands.
Experience
P.V.C.u. pipes are a proven part of modern building and civil engineering and pressure pipes up to 24" diameter have for many years been used for gravity drainage schemes in all parts of the United Kingdom. They have been used on many major trunk roads and motorways, often with the original pipe design changed to make the most of the wider ranges of sizes available in P.V.C.u.
The crushing strength requirements of rigid material are not relevant to P.V.C.u. because of its flexibility. The wall thickness/diameter ratio of Sewerdrain has been selected so as to be comparable with class B "Pressure Pipes" to BS 3505. The outside diameters are in accordance with ISO/R161 recommendations.