Teava PPR Fibra Compozit SDR 9 sau Multistrat Pex-a Al la o casa ?

However, it is the cleanest, most environmentally friendly method of the three, since it does not involve other chemicals and uses only high-energy electrons to split the carbon-hydrogen bonds and facilitate cross-linking.

TECE PEX-a pentru incalzire in pardoseala este alba.
TECE PEX-c pentru instalatii sanitare este galbuie.
TECE PEX-c pentru instalatii de incalzire are un strat gri la exterior.

Pentru realizarea barierei de oxigen se foloseste copolimerul EVOH (etilena – alcool vinilic) care este adaugat pe toata suprafata exterioara a tevii. Tevile au trei straturi cu bariera de oxigen (EVOH) si legate cu adeziv specific (anhidrida maleica).

Rolul barierei de oxigen:

Impiedica formarea de microorganisme care s-ar depune pe peretii interior ai tevi;
Reduce coroziunea elementelor metalice cu care apa de incalzire vine in contact (echipamente de incazire si jonctiune);
Protejeaza teava de atomi liberi de oxigen care se pot combina cu atomi de hidrogen din structura moleculara a polietilenei si care in timp duc la fenomenul de imbatranire a tevilor.

Viteza de difuzie a gazelor se masoara in cm3 de gaz ce trec prin folia de polimer de 20 microni grosime pe o suprafata de 1 m2 timp de 24 de ore. Comportamentul pentru EVOH si polimer este:

EVOH – 0.2
PE – 12.000

Diferenta este mult mai mica in cazul copolimerului si explica astfel necesitatea utilizarii PEX cu bariera de oxigen!

What Is The Difference Between PERT Pipe And PE-RT Pipe?
https://www.kangyupi...p-40708583.html

The difference between PERT pipe and PE-RT pipe lies in the difference of raw material, production process and connection mode:
1. Raw material PERT pipe: the raw material of PERT pipe is chemical crosslinked polyethylene. PE-RT pipe: the raw material of PE-RT pipe is heat-resistant polyethylene.

DOWLEX™ 2388 Polyethylene Resin

An ethylene/octene-1 copolymer produced in the proprietary solution process of Dow. It has a unique molecular structure with a controlled side chain distribution, which provides excellent stress crack resistance properties combined with outstanding long term hydrostatic strength.

Uses

Hot / cold drinking water distribution
Radiator connectionsHeating / cooling applicationsMono- and multi-layer pipeIndustrial applications

Benefits

Suitable for elevated temperatures without crosslinking
Outstanding taste and odor performance Excellent processability

https://www.dow.com/...z.html#overview

THREE-LAYER ML PIPE

Outer plastic layer: second-generation PE-RT for protection against corrosion and mechanical damage
Central aluminium layer: makes the multilayer pipe stable, bendable and forms a barrier against diffusion
Inside layer: corrosion-resistant and food-safe second-generation PE-RT

https://www.geberit-.../geberit-mepla/

PE-RT compound – Type II

PERT compound -type II of GS RT-221 grade could be use  for both 3 layer and 5 layer hot water pipes production.

GS RT-221 is compatible with tie layer adhesive of GS ARD-2102 , GS ARK-2302. and oxygen barrier Ethylene vinyl base oxygen barrier compounds.

https://elpolymer.co...pe-rt-compound/

1.1.3. Physical properties, marking

The polyethylene PE-RT, from which the pipes in the Uponor MLC system are made, is made of high quality octane copolymer of polyethylene, known under the trade name DOWLEX 2388, resistant against high temperatures according to DIN 16833.

The basic mechanical and thermal properties of the pipes of the system are shown in Table 1-4.

CONCLUSIONS

The conducted investigation shows very clearly the differences in the four grades of PE used for pipe production, from PE-63 which undergoes brittle failure and LDPE which undergoes ductile failure to Dowlex which has a high strain capacity and thus a significant fracture resistance, indicating its ample capacity to resist both rapid and slow crack propagation and its high long-term strength owing to its developed network of entanglements of amorphous phase.

Kiwa guideline BRL-K536 H “Plastics piping systems of PE-RT type 2 intended for transport of hot and cold drinking water”

This product certificate is only valid in combination with a Kiwa certified plastics piping system.
Advice: consult www.kiwa.nl in order to ensure that this certificate is still valid.

PE-RT ultraLine pipes

Subject
5-layer PE-RT ultraLine pipes

Product characteristics
The product complies to BRL K536-H Plastics piping systems of PE-RT type 2 intended for transport of hot and cold drinking water.

Fitness for contact with drinking water

This product is approved on the basis of the requirements for hygienic aspects set in the "Regeling materialen en chemicaliën drink- en warm tapwatervoorziening" (“Materials and chemicals in the supply of drinking water and warm tap water Regulation” dated 01-07-2017; published in the Government Gazette).
These hygienic aspects are based on two main criteria. The product shall permanently comply with:
• The product recipe approved during the assessment procedure. This recipe is not to be changed without prior approval by Kiwa according to the Kiwa approval procedure for the hygienic aspects;
• Specific product requirements for the hygienic aspects.
The recipe and specific product requirements are laid down in the for confidentiality reasons undisclosed ‘appendix hygienic aspects’ to this certificate.

Pipes
The minimum required marking on the pipes shall be:

• or * + 2/ 10 bar;
• material identification: PE-RT Type 2;
• the build up of the pipe; PE-RT2/EVOH/PE-RT2;
• certificate number of accompanying technical approval-with-product certificate of the piping system;
• the manufacturer’s name, trade name, system name or logo;
• nominal outside diameter and nominal wall thickness of the pipe in mm;
• production code.

Project title "Increasing the competitiveness of TWEETOP Sp. z o.o. through the implementation of an innovative technology for the production of Pert II/Evoh/Pert II multilayer pipes with increased mechanical strength" No. RPZP.01.05.00-32-W043/21 as part of the Regional Operational Programme of the Zachodniopomorskie Voivodeship 2014–2020 Priority Axis 1 Economy, Innovation, Modern Technologies". Measure 1.5 "Investments of enterprises supporting the development of regional specializations and smart specializations.

Pagina #12 :
https://bazakonkuren...pi/files/784454

REHAU, azienda specializzata nello sviluppo di soluzioni per il settore idrotermosanitario, ha progettato FASTLOC per semplificare il lavoro quotidiano dei professionisti termoidraulici e ottimizzare i tempi di cantiere. Il sistema è composto da tubi multistrato metallo-polimero (PE-RT Type II/Al/PE-RT Type II), disponibili anche in versione preisolata, che offrono un eccellente comportamento alla flessione e un’elevata resistenza alla deformazione.

https://www.infoimpi...ioni-immediate/