PPR Pipe 90mm Aluminum Layer

RAKtherm Stabi PPR Pipe (Aluminum Layer / Multilayer Composite), 90 mm, PN 25 is a reinforced polypropylene random copolymer (PP-R) pipe with an integrated aluminum layer. It is manufactured in the UAE (by Gulf Plastic and Converting Industries / Tahweel under the RAKtherm brand in Ras Al Khaimah) and designed for pressurized hot and cold water systems, including HVAC water supply, heating, and chilled water networks.

Description

This is a Stabi (stabilized) composite pipe (typically PPR/AL/PPR construction). It consists of:

• An inner layer of PP-R (potable-water safe, smooth for high flow and hygiene).
• A middle aluminum layer (approximately 0.2 mm thick) that acts as a mechanical stabilizer, oxygen barrier, and thermal expansion reducer.
• An outer protective PP-R layer.

Some versions include a special black UV-resistant outer layer (Stabi UV / RRSV) for outdoor or sun-exposed installations.

Key advantages over standard (homogeneous) PPR pipes:

• Linear thermal expansion reduced by ~75% (or at least 75–80%), approaching the behavior of metal pipes.
• Higher flow rate (~20% increase) due to thinner effective walls and larger internal diameter for the same outer diameter.
• 100% oxygen barrier (prevents corrosion in boilers, radiators, and metal components).
• Higher impact strength, better pressure resistance at elevated temperatures, and greater support spacing possible.
• Non-corrosive, chemically resistant, non-toxic, and suitable for potable water (complies with sanitary norms).
• Service life typically designed for 50 years under proper conditions.
• Lightweight, easy to handle, and joined by heat fusion welding (leak-free joints of the same material).

It is marketed as an engineered solution for residential, commercial, industrial, HVAC, and specialized applications.

Specifications (90 mm PN 25 Stabi)

From RAKtherm catalogues (DIN 8077/8078 compliant; aluminum thickness ~0.2 mm):

Pressure ratings decrease with temperature (typical for PP-R systems; exact values depend on service life and safety factors). PN 25 indicates the highest pressure class for demanding hot-water or high-rise applications. Always refer to the manufacturer’s pressure-temperature tables for the specific design conditions.

UV versions add a black outer layer for outdoor durability.

Applications / Usage

• Hot and cold potable water supply (residential, hotels, hospitals, offices, schools).
• HVAC systems: chilled water, heating water, and circulating systems.
• Central heating and radiator systems.
• Air conditioning / refrigeration water loops.
• Swimming pool water circulation.
• Solar water heating systems.
• Industrial networks (including aggressive fluids where PP-R is compatible).
• Agriculture and other pressurized fluid transport where hygiene and corrosion resistance are required.
• Outdoor/exposed installations (prefer UV version).

Not typically recommended for direct burial without proper protection or for certain aggressive chemicals without verification. Suitable for both above-ground and concealed installations.

Installation

Joints are made by socket fusion welding (heat fusion) using RAKtherm or compatible PP-R welding tools. The aluminum layer requires specific preparation.

Basic steps:

1. Cut the pipe square and cleanly with a proper pipe cutter (no skewed cuts).
2. For Stabi pipes: Peel/remove the outer PP-R + aluminum layer completely over the insertion depth using a dedicated peeling tool/scraper (critical step so pure PP-R contacts the fitting).
3. Clean and dry the surfaces; mark the welding depth.
4. Heat the pipe end and fitting simultaneously on the welding tool (typically ~260°C) for the specified heating time without twisting.
5. Remove from the tool and push together firmly (without rotation) to the marked depth; hold briefly.
6. Allow full cooling before stressing the joint. The system can usually take full load after ~15 minutes (confirm with manufacturer guidelines).

Approximate welding parameters (typical for PP-R; confirm exact times with current RAKtherm tools/manual for 90 mm):

• Insertion/welding depth ≈ 29 mm.
• Heating time ≈ 40 seconds (example range; larger diameters take longer).
• Joining/holding and cooling times as per table (cooling often several minutes).

Additional notes:

• Support spacing can be increased versus standard PPR because of the aluminum stabilizer (consult RAKtherm tables; spacing depends on temperature, orientation—horizontal vs vertical—and load).
• Account for residual thermal expansion (much lower than plain PPR) with proper anchors, expansion loops, or compensators where needed.
• Use only compatible RAKtherm or approved PP-R fittings.
• For outdoor work, prefer the UV-protected version.
• Tools, temperatures, and times must follow the manufacturer’s current instructions exactly for a reliable joint. Improper peeling or heating is a common cause of failure.

Additional Information

• Brand/Origin: RAKtherm (UAE manufacturing).
• Quality: Produced under German standards with quality systems; certifications typically include relevant international approvals (e.g., related to DVGW, SKZ, TÜV references in catalogues).
• Warranty: Manufacturer offers extended guarantees (e.g., 15 years on components in some documentation—confirm locally).
• Availability: Sold through distributors in the UAE and exported; common in 4 m lengths. Check current pricing and stock with local suppliers (prices fluctuate with raw materials).