PP-Rc pipe systems are produced from a type of polypropylene known as polypropylene random copolymer, often referred to as Type III PP-Rc (commonly known as PPR). This raw material is obtained through the cracking of petroleum, where propane-monomer polymerizes with polypropylene co-monomer to form polypropylene random copolymer. We exclusively utilize one of the best PP-Rc raw materials globally, approved to produce pipes and fittings in accordance with DIN 8078 and DIN 16962 standards.
The PP-Rc raw material is a thermoplastic resin supplied in pre-colored granules. This raw material is transformed into finished products by raising the temperature, which plasticizes the material. This process allows the production of pipes through extrusion and fittings through molding.
Plastic pipes have become more resistant as they have evolved. The first produced polypropylene had a structure consisting of propylene molecules, which was referred to as Type 1 Polypropylene homo-polymer. Later, propylene molecules with mixed sequences were introduced alongside the propylene molecules, leading to what is known as Type 2 Polypropylene block copolymer. Subsequently, the Type 3 product was developed, which includes ethylene molecules regularly sequenced among the propylene molecules.
Today, due to their specific characteristics, Type 2 and Type 3 are widely used. Type 2 is employed primarily in cold water networks and is not suitable for use with hot fluids. On the other hand, Type 3 can be used for hot water systems because it resists hot fluids.
VIALLI PP-Rc pipes and fittings possess adequate UV stability to protect them from UV rays. Nevertheless, it is not advisable to continuously expose these pipes and fittings to direct sunlight for outdoor pipeline installations. It is recommended to apply an acrylic paint coating to the pipes or to shield them from direct sunlight by providing a protective covering or installing them in a duct. This precaution helps extend the lifespan and maintain the performance of the pipes and fittings when used outdoors.
Normally, it is not mandatory for plumbers to install insulation because the thermal conductivity of PP-Rc piping systems is lower compared to metal piping systems (0.24 W/mK). However, for centralized heating systems, where preventing heat loss and isolating pipelines from other utilities is important, it is advisable to insulate these lines. The required thickness of insulation is significantly lower compared to conventional lines due to the inherent properties of PP-Rc piping systems.
VIALLI PP-Rc system can be connected to other metal systems easily by a flange or a metal adaptor. (BS 6920)
The Deutsches Institut für Normung (DIN) is Germany's institute for standardization. It is a technical and scientific association recognized by the German government as the national standards body representing Germany's interests at international and European levels. DIN provides a forum in which representatives from manufacturing industries, consumer organizations, commerce, the trades, service industries, science and technical inspectorates, and government can discuss and define their specific standardization requirements, recording the results as German Standards.
Following standards are used to produce VIALLI pipes and fittings:
Standard |
Concern Production |
DIN 8076 |
Standard for Testing metal threaded joints |
DIN 8077 |
Polypropylene Pipes. Dimensions |
DIN 8078 |
Polypropylene Pipes, General Quality Requirements & Testing |
DIN 16962 |
Pipe joints and elements for Polypropylene Pressure Pipes |
DIN 1988 |
Drinking Water Supply Systems, Materials, Components, Appliances Design, and installation |
DIN 16928 |
Pipe joints & Elements for Pipes, Laying-General Directions |
DIN 2999 |
Standard for fittings with threaded metallic insert |
EN ISO - 15874 |
Plastic piping system for hot & cold-water Installation – (PP) |
BS 6700 |
Design, Installation, Testing and Maintenance of Services Supplying Water for Domestic use within buildings and their Cartilages |
DVS 2207 |
Welding of Thermoplastics |
DVS 2208 |
Welding Machines and Devices for Thermoplastics |
PP-Rc pipes have a service life of 50 years according to DIN Standards for in-house applications. To have detailed information regarding different temperatures and pressure rates, please refer product catalogue
PP-Rc products can safely be used for Drinking water. VAILLI PP-Rc products have got all international Approvals as well as the approvals of the sales territories.
PN stands for Nominal Pressure, it is numerical designation used for reference purposes related to mechanical characteristics of the component of a piping system. A PN-20 pipe mean the pipe can withstand pressure Up to 20 Bars.
VIALLI fittings can withstand temperature above 95°C and pressure up to 25 kg/ cm2, (25 Bars) hence categorized under PN-25.
The life Span of PN20 is longer than PN-16 pipes under the same temperature and pressure conditions. Especially for the exposed installations as the expansion of PN-20 pipes are 1/5 of PN 16 pipes sagging and snaking problems are avoided.
PP-Rc Pipes with all thickness of OD/ SDR is matched as the Equivalent PP-Rc pipe for a SDR Pipe.
PN-10 is regarded as equivalent to SDR 11 Because, PN 10 Pipe of 20 mm OD has thickness approx. to 20/11=1.8
PN-10 160 mm has thickness approx. to 160/11=14.55
Likewise, SDR 7.4 is matched as PN-16 and SDR 6 as PN-20.
PN 10 – Cold water distribution and floor heating systems
PN 16 – Higher-pressure cold-water distribution and domestic hot water system at lower Pressures.
PN 20 – Hot water distribution Central
PN 25 - Higher pressure Hot water distribution Central and Domestic
If it is a nail or a drill hole (10.5mm deep max) you may use “VIALLLI PP-Rc Hole Repair Kit to repair the hole in the pipe. If the damage part of the pipe is not concealed yet (before the pressure test is conducted), the recommended procedure is to cut that part and replace it by a new part through normal welding of a socket
At lower temperature of 0°C and below, the flexibility of PP-Rc pipes reduces, and impact strength also reduces. This makes pipes more prone to mechanical damage against impact loads. To avoid the damages at low temperature, it is advisable to insulate the pipelines.
VIALLI pipes and fittings have a combustion point of 330°C and a burning point of 360°C. These properties conform to the B2 (Normally inflammable) class fire requirements for normal combustibility according to DIN 4102. In the event of a fire, PP-Rc pipes and fittings emit carbon dioxide and water. Additionally, depending on the availability of oxygen, small amounts of carbon monoxide gas, molecular hydrocarbons, and oxidation products may also be emitted. Even in cases of incomplete combustion, the materials emitted are less toxic than those from wood or conventional pipe systems under similar conditions.
The process of joining PP-Rc pipes and fittings is very simple and results in inseparable water joints. This is achieved using a straightforward welding machine that melts the internal surface of the fittings and the external surface of the pipe at 270°C, allowing the material of the pipe and the fitting to meld together. Because both the pipes and fittings are produced from the same material, the connection is typically homogeneous.
Alignment up to 5 degrees relative to the axis of the pipe can be done immediately after jointing.
It is advised to used sharp cutting tools to cut the pipe with no burrs, VIALLI provide cutting tools of size 20-40, 20-63, 50-110, 160, 200 & 250.
The pipe size is measured using the metric unit "mm" (millimeter) of its outer diameter. PRR fittings are measured using “mm” (millimeter) of inner diameter and metal threaded fittings treaded side size is measured in inches.
VAILLI threaded fittings are manufactured using stainless steel inserts, tin bronze inserts, brass with nickel platted inserts, and natural brass inserts and its threading is made as per British Standard Threading.
Possible linear thermal expansion/contraction needs to be taken into consideration during designing and installation. Stressing of pipes can be avoided by providing flexible free length and proper supporting.
This joining results in blockage or reduction in inner diameter. At joining point hence it’s recommended to avoid as it can affect the function of the system.
Using glue connections is not recommended as they cannot provide a 50-year guarantee against leakages. Additionally, glue connections are susceptible to issues like termite attacks and frequent maintenance requirements, which can impact the hygienic and long-term performance of the VIALLI PP-Rc Pipe system.
Before any pipes are filled or cemented in concealed applications, they must undergo hydrostatic testing to check for pressure loss or leaks. The testing involves pressurizing the closed system, with all ends sealed using caps and pipe plugs, with water up to 25 bar for PN-20 and PN-25 pipes, and up to 15 bar for PN-16 pipes, all at room temperature. The pressure should be maintained for at least 8 hours to detect any pressure drop. This process is repeated to confirm the absence of even minor leaks. If a significant pressure drop is observed, the specific area of leakage must be identified and rectified.
VIALLI utilizes Borealis raw materials to manufacture PEXa pipes following DIN 16892 and DIN 16893 standards.
The following standards are used to produce VIALLI pipes and fittings:
Standard |
Concern Production |
DIN 16892 |
Cross linked high-density polyethylene PEXa pipes - General quality requirements and testing |
DIN 16893 |
Cross linked high-density polyethylene PEXa pipes – Dimensions |
According to DIN Standards for in-house applications, PEXa pipes have a service life of 50 years.
PEXa products can be safely used for drinking water. VIALLI PEXa products have obtained all international approvals alongside approvals from the relevant sales territories, including WRAS (Water Regulations Advisory Scheme) approval.
It is advised to use sharp cutting tools to cut the pipe with no burrs; VIALLI provides cutting tools.
The pipe size is measured using the metric unit "mm" (millimeter) of its outer diameter. PEXa fittings are also measured using "mm" (millimeter) of inner diameter, and metal threaded fittings treaded side size measured in inches.
Yes, it is so easy to disconnect the fittings to do the required maintenance and re-connect it again.
If you follow the instructions above, the risks of over- or under-tightening are minimal. Since all systems must be pressure tested before being put into use, it is possible to tighten the fitting more if there’s a leak at the connection point. To avoid over-tightening the compression nut, do not use excessive force and wrenches larger than indicated when installing the fitting.
Yes, when the compression nut is tightened, the open ends of the O-ring come together, exerting pressure upon the VIALLI PEXa pipe, allowing it to compress over the fitting's barbs.
The O-rings are designed to prevent water leakage. The barbs aim to prevent the fitting from popping out under pressure from the pipe. It is unnecessary to remove the O-rings from the fitting, and there is no need to lubricate them in any way.