Nowadays, Polypropylene is one of the most extensively used plastics in the world due to its diverse applications and being economical. GREENLIFE PP-R Pipes and fittings are made of High Molecular Weight Polypropylene Random Copolymers suitably stabilised for high temperature applications and especially with high environmental stress cracking resistance that means long service life.Due to its high extraction resistance it does not change the organoleptic properties of water.Polypropylene Random Copolymer Pipes have smooth internal surfaces and are not suitable for algae and scale formation and minimize the pressure losses.Polypropylene Random Copolymer Pipes are classified as TYPE 3 in the German Standard DIN 8078. The production process used for PP-R pipes on the easy workability of this material make it possible to obtain extremely smooth inner surface. Pressure loss changes are very low in the normal span of operating temperatures (up to 60°C)in a potable water line.Therefore, calculations are made with reference to a 10°C temperature.
All PP-R fittings are designed for PN20 pressure classification and the fittings program covers sockets,t-pieces, elbows,reducers, adaptors,anions, etc.In addition to these fittings PipeLife also provides equipment such as welding machines, welding dies,pipe shawers, valves etc.The reliability of pipe installations depends on pipe/fitting joints as well as the material used in their production.Concerning the hot&cold system,all pipes and fittings are manufactured from the same material and result therefore in homogeneous joints.Mainly two techniques are used to join PP-R Pipes and Fittings.The principle characteristic of PP-R is the possibility to make a molecular bond by means of welding.
a) Socket welding (polyfusion welding):
Is made by heating the sockets and pipe ends by electrical heating elements.This technique is the most practical and economical method which has been widely accepted and applied in whole Europe.
b) Electrofusion Welding:
Is realised by the use of electrofusion fittings.In this technique you apply electrical current to specially produced fittings (With built-in wires) for a certain time to have a chemical bond between the pipe and the socket.
With the above mentioned welding techniques very reliable joints are obtained.The welded joints are as strong as the pipe itself. In the tensile testing of a joint,the pipe may break before the socket welded joint.But electrofusion technique is more expensive than socket welding.
- Measure and cut the pipes perpendicularly to the required lenght.
- Smooth off any sharp corners of the cut if any.
- Wipe the pipe and the socket of the fittings with a dry cloth to clean the dirt or grease.
- Switch on the welding machine and check that the welding dies are at the required temperature of 260° (+/- 10°C).When it reaches that degree,the thermostat indicator lamp shuts off.
- Push the pipe end into the welding die very quickly and firmly while slipping the fittings over the other die.During this operation the pipe and the fitting must be held firmly without any turning movement.
- The surfaces of the pieces to be joint must be heated according to the period given in the table above.
- After heating session the pipe-end and the fitting are withdrawn from the welding dies and immediately joined without any turning movement.
- The two pieces must be held together for the assembly time given on the table.
- The welded joint must not be mechanically stressed until the cooling time has elapsed.
- After each welding operation the dies of the welding machine must be thoroughly cleaned.
During laying down of installations PP-R pipes may be required to be bent.Bending can be made only by heating,pipes must not be exposed to flame directly,instead hot air blowing equipment should be used.
For bending PP-R pipes it is sufficient to heat the pipes up to 140°C.Recommended minimum bending radius is given in the following table:
Wall clamp distances for the horizontally laid sanitary pipes depend on the pipe material,pipe dimension,weight of the pipe in full and the operational temperatures of the system. Recommended pipe clamp distances are given in the table. The same clamp distances are advised for the vertically laid pipes as well.
- Although PP-R pipe material is stabilized for use at elevated temperature and against UV radiation, do not expose the pipes and fittings to direct sunlight for a long time.
- The pipes and fittings should be protected from impact of hard and sharp objects,carried carefully and kept tidy.
- Use only special scissors (supplied by PIPELIFE) to cut the pipes.
- Clean the dirty pipes and fittings first with a clean piece of cloth and then start the welding process
- Do not use conical threaded fittings,prefer the straight threaded fittings and valves
- Do not over-tight the fittings and valves
- Do not apply flames to obtain and bends or crossover, as the direct exposure to flames may cause damage to the pipe, instead please use the hot air blowing equipment. The highest heating temperature amounts to 140°C.
- Pipe and fittings kept at very low temperatures are to be preheated before the welding process
- Prefer to use teflon tape instead of hemp for the thread connections. Avoid over wrapping by excessive amount of tape
- At temperatures 0°C and below, tendency to break increases. Therefore installation at low temperatures should be made with care
- During transportation PP-R pipes should be loaded in good order, otherwise pipes may be deformed
- Polypropylene must be stored in a dry place and out of direct sunlight. The quality of the product may suffer due to storage under improper condition. Storage height should not exceed 1.5 m. GREENLIFE having all those advantages and properties mentioned above is very suitable for plumbing applications and radiator heating applications.