Heating Systems

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AJAX PANE

AJAX HAS BEEN KNOW TO ENHANCE USER INTERFACE
AJAX HAS BEEN KNOW TO ENHANCE USER INTERFACE
AJAX HAS BEEN KNOW TO ENHANCE USER INTERFACE
AJAX HAS BEEN KNOW TO ENHANCE USER INTERFACE

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District HeatingCross-Linkable CompoundsFluoropolymersSulfone Polymers

In piping systems for hot water transport applications, like district heating or geothermal heating, the selected material must possess high pressure resistance together with excellent long-term performances at high temperatures, where traditional polyolefins are limited in use.

Polidan® PEX

TUX 100 – A specialty designed crosslinkable PEX-b compound, allows pipes and fittings to be thermally welded similar to PE pipe and cross-linked in situ to achieve higher characteristics than standard PEX materials.

Solef® PVDF is a semi-crystalline, melt-processable fluoropolymer that offers excellent resistance to many chemicals as well as outstanding barrier properties to oxygen. It has exceptional performance in long-term hydrostatic strength and can be used up to 120°C. It has been used successfully in domestic water supply applications for nearly 20 years and has an equally impressive track record in the chemical industry.

Key Features
• Excellent resistance to chemicals and hot chlorinated water
• Outstanding long-term hydrostatic strength
• Exceptional fatigue resistance
• Good barrier properties against a broad range of chemicals
• UV resistance for outdoor applications
• Smooth surface prevents biofilm adhesion
• Resistant to flame propagation

Polidan® PEX is a family of silane cross-linkable polyethylene compounds. This means that permanent connections, known as cross-links, are chemically formed between molecular chains to create a three-dimensional structure. As a result, crosslinked polyethylene (PEX) has better thermal stability, mechanical properties and resistance to chemical attack than thermoplastic polyolefins.

Monolayer and multilayer PEX pipes made from Polidan® PEX compounds are flexible and have excellent strength from below freezing up to 95°C. PEX piping systems are quieter than rigid metal piping systems and require fewer fittings, making them easier and less costly to install.

Outperforms Thermoplastic Polyolefins
• Improved resistance to oxidative aging
• Higher strength at elevated temperature
• Better chemical and chlorine resistance
• Higher heat resistance
• Improved low-temperature impact strength
• Superior resistance to crack propagation
• Better abrasion resistance

Performance Data

Polidan® PEX for Water Delivery Systems
	Density ASTM D 792, g/cm3	MFR_190/5 ISO 1133, g/10 min	Melt Process
T/A-HF	0.942	1.70	Extrusion
T/A-LX	0.945	1.50	Extrusion
T/A	0.948	0.50	Extrusion
T/A-SL	0.949	2.40	Extrusion
T/A-XT	0.949	2.50	Extrusion
TUX 100	0.953	1.30	Extrusion, Injection Molding
T/A-LV	0.955	5.50	Extrusion
SI 20	0.956	9.50	Injection Molding

Long-Term Hydrostatic Pressure Tests
		ISO 15875 Standard Requirements for PEX Pipes		Performance of PEX Pipes made from Polidan®
Temperature, °C	Conditioning Medium	Hydrostatic Stress, MPa	Time of Stress, Hours	Hydrostatic Stress, MPa	Time to Failure, Hours
20	air or water	12.0	1	13.0	>1,300
95	air or water	4.8	1	5.0	>19,900
95	air or water	4.4	1,000	4.6	>40,000
110	air	2.5	8,760	2.8	>16,000

Udel® PSU, Radel® PPSU and Acudel® modified PPSU

These tough, heat-resistant plastics can be molded to tight tolerances and exhibit low creep under a sustained load at elevated temperatures. This, combined with their excellent oxidation resistance, has made sulfone polymers a reliable choice for applications that require continuous exposure to hot chlorinated water.

Key Features

Excellent compressive strength
Low tensile and compressive creep
Outstanding long-term hydrostatic strength
Withstand continuous exposure to hot chlorinated water

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Creep

Low Compressive Creep

Sulfone polymers have low compressive creep, meaning they exhibit only a slight deformation under a continuously applied load. This allows components made from these materials to maintain a reliable seal over time, even at elevated temperatures.

Hot Water Resistance

Exceptional Resistance to Hot Chlorinated Water

These micrographs were taken of insert fittings made from Radel®, Acudel® and Udel® sulfone polymers that were continuously exposed to hot chlorinated water for 1600 hours. These test conditions are extremely harsh and are significantly more aggressive than industry standards for PEX piping systems.

As shown below, no cracks have formed in any of the sidewalls and no oxidation has occurred on the surface of the fitting made from Radel® PPSU. Very little oxidation has occured on the surface of the Acudel® modified PPSU fitting, and only a small amount on the surface of the Udel® PSU fitting.

LTHS

Determining Long-Term Hydrostatic Strength (LTHS)

When designing a pressurized system, it’s important to understand how a material performs when exposed to constant stress in the presence of water. Data from creep-rupture curves generated at various temperatures can be extrapolated to predict a material’s LTHS for a given set of conditions. These values are then used to determine design stresses, which should include appropriate safety margins.

50-year prediction and lower prediction limit (LPL) Values ISO 9080 Method 4
		Radel R-5100		Acudel 22000		Udel P-1700
Temp., °C	Time, hours	Mean, MPa	LPL, MPa	Mean, MPa	LPL, MPa	Mean, MPa	LPL, MPa
20	438,000	41.5	36.6	39.4	33.4	13.4	–
70	438,000	25.4	21.3	18.9	15.2	5.7	–