Other Line Systems

Line systems made from VESTAMID^® polyamide 12 and polyamide 612 compounds are far superior to the traditional reinforced or unreinforced EPDM hoses or metal tubes for circulating coolant between the radiator, pump, heat exchanger, and coolant expansion tank. They are:

• Lighter
• Thinner, because of their strength
• Easily thermoformed
• Not prone to fatigue failure
• Quickly and easily joined via quick connectors, and therefore more economical
• Low temperature impact-resistant
• Resistant to flying stones
• Chemical resistant, therefore not subject to corrosion
• Able to withstand brief external temperature loads of up to 150° C
• Highly resistant to heat aging
• Good resistant to burst pressure

Monotubes for ventilation systems

In the cooling water ventilation system—for example, between the coolant expansion tank and the radiator—the hot ethylene glycol-water mixture does not flow through the lines continually. Monotubes made from the hydrolysis-stabilized compounds VESTAMID^® LX9008 (PA12) or VESTAMID^® DX9304 (PA612) are well suited for this area, because they absorb little of the solution and therefore do not swell. Multi-layer tubes, as described below, are also suitable for this application.

Multi-layer tubing for coolant lines

Coolant lines that constantly come in contact with hot coolant call for multi-layer tubing. For this application, Evonik has developed VESTAMID^® based multi-layer tube (MSR) systems that are already being used by renowned manufacturers.

With diameters of up to 30 mm and wall thicknesses of 1 to 1.5 mm, the systems of the MSR 8000 series are structured with three layers:

• The inner layer consists of polypropylene customized to the application.
• On top of this sits an adhesion-promoting layer.
• The outer layer is made of high-grade VESTAMID^® specialty polyamide.

Because of a modification carried out at the molecular level, the compound for the MLT 8000.3 provides higher flexibility without the need to add a plasticizer. The MLT 8000.1, on the other hand, features higher bursting strength, especially at high temperatures. This allows the user to select a system tailored to his or her specific requirements.

Coating protection against corrosion

Steel and aluminum alloys are used in applications that do not require the flexibility of plastic tubing or that specifically call for metal tubing. A coating of VESTAMID^® X7377 or VESTAMID^® LX9001 can improve the corrosion and flying-stone resistance of this metal tubing.