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Frequently Asked Questions (FAQ's)


What is the life expectancy of Rigid PVC pipe?

The durability of rigid PVC pipes is related, as it is for all other thermoplastics materials, to the chemical degradation of the polymer, used in the pipes. However unlike other thermoplastic pipes rigid PVC pipes do not oxidize.

However, when the pipes are buried in the ground, no chemical degradation is expected to take place. For this reason the durability of the rigid PVC material in buried pipes is expected to be very long (May even be more than 1000 years).

Real experience in Germany³ has shown that buried rigid PVC pressure pipes dug up after 60 years of active use were proven to be fit for purpose when analyzed and likely to have a further life expectancy of 50 years.


What are the main advantages of installing rigid PVC pipes compared with other solutions?

As a result of the combination of the following characteristics, rigid PVC is generally the most efficient, quick installing and cost-effective of all the spectrum of solutions for piping.

Lightweight: Rigid PVC pipes are light and easy to handle (up to 6 m length), significantly reducing the need for mechanical support for placing and fixing the pipes together, leading to a cost efficient installation.

Joints: Rigid PVC piping systems can be installed with different types of joints: solvent cement joints and push-fit joints. Across Europe, push-fit joints are usually preferred for municipal installations

The use of push-fit joints is a very important characteristic as it not only assures a watertight, safe and durable union, but permits a fast and simple mounting, an important cost saving during installation, as it avoids using complex welding operations and costly investments in sophisticated equipment and specialized skills.

Fittings and special operations: Rigid PVC pipe systems are normally completed with the widest range of fittings and ancillary products, allowing a modular installation and high quality of the full network. When finishing work has to be done by hand (For example making holes, installing saddles and cuts in the pipes), rigid PVC is easy to work with, and does not need complex tools or special expertise.


What is a "flexible" pipe and how are they designed?

PVC-U piping systems belong to the category of so called "flexible pipes". This flexibility provides a great advantage compared to the more "rigid pipes" made of traditional materials such as concrete or clay:

For flexible pipes: the soil supports all the stresses on the pipe (including soil weight) and the pipes deform slightly but do not break

For rigid pipes: the soil concentrates the stresses directly on to the crown of the pipe, these pipes do not deform but a failure mode results in a break in the pipe.


What effect does exposure to ultraviolet radiation have on rigid PVC pipe?

Prolonged exposure of rigid PVC pipes to direct sunlight may cause a thin film of degradation on the exposed surface of the pipe over time. This microscopic layer, with a thickness of about 0.05 mm, will gradually become visible as discoloration (so called bleaching) and it stops once the surface exposure ceases.


Is there any taste or odor in water passing form rigid PVC pipes?

Due to absence of migration and low bacterial growth in rigid PVC, the organoleptic properties of rigid PVC are generally very good. This is also confirmed by regular testing in different European institutes.


Does chlorinated drinking water affect rigid PVC pipes ?

Across Europe, with some exceptions like the Netherlands and Denmark where ground water is exclusively used, chlorination of drinking water is a common way of avoiding the presence of pathogen bacteria and to ensure that EU member states conform to the EU drinking water directive.

Although chlorine can affect the taste and odor of water, this has long been considered as the best way to provide safe water at the tap.

The concentrations used in Europe are calculated so that the remaining chlorine at the tap is in the order of 0.1mg/l


How do rigid PVC pipes perform in fire?

PVC-U is inherently self-extinguishing and does not require any additional flame retardants to meet most flammability requirements.


What are the temperature limitations of PVC pipe?

The maximum use temperature for PVC pressure pipe is 140 degrees F. PVC DWV piping readily withstands the hot and cold water discharges that are normally associated with plumbing fixtures.


How do PVC pipes behave at sub-zero temperatures?

PVC pipes perform well at very low temperatures and to highlight the strength of PVC pipes in extreme conditions. The impact test shows how well a solid wall pipe, made of a standard PVC formula with no impact modifiers, of 110mm diameter responds to a weight of 8Kg being dropped from a height of 2m.


Can rigid PVC pipes withstand a vacuum? What is the maximum vacuum that rigid PVC pipes can withstand?

Rigid PVC pipe systems can withstand a vacuum and can operate under pressures as low as -0.9 bar in regard to the pressure class of the Rigid PVC BSS 3505 : 1968.

For non-pressure and vacuum to -0.3bar, rigid PVC sewer systems can be used.


What is the length of pipes?

It is conventional to use rigid PVC pipes of lengths between 3m and 6m in all applications although it is also possible to use pipes in lengths of up to 12 m on special projects. These relatively short lengths allow rigid PVC pipes to be stored and transported easily and also ensure that they are very easy to install. These short lengths also eliminate any problems associated with longitudinal bending.


What size range can SHAVYL extrude?

SHAVYL can extrude plastic tubes and profiles ranging in size from approximately 1/2-inch O.D. to a maximum 14-inch O.D. with wall thickness from 1.5 mm to 21.6 mm ± 0.5
 
     
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