The corrosion behaviour of the Carbon Steel RapidPress press-fit system is defined by the unalloyed Carbon Steel used and is suitable for:
• Closed heating systems;
• Closed cooling and refrigeration circuits; compressed air system;
• Closed solar cycles.
Closed heating and cooling systems do not have air, thus no risk of corrosion. The small amount of oxygen that enters the system during filling does not cause any problems as it reacts with the entire metallic surface inside the system and is reduced. Additionally, oxygen is released when heating water is heated and through valves in the system.
The systems must be filled in accordance with VDI 2035. Oxygen increase can also be prevented by the use of oxygen binding materials. However, these must be approved by The Metal Company beforehand. When filling the systems, the pH value must not fall below 7.2 (drinking water).
Bi Metal Corrosion
In closed circuit of heating/cooling installations executed with Carbon Steel, it is possible to insert single fittings made from different raw materials, including Stainless Steel components in any order.
Closed circuit networks entirely executed with Carbon Steel (pipes and fittings) must be separated from stretches made with Stainless Steel (pipes and fittings) through the use of shut-off valves or bronze nipples (> 80 mm) for protection against corrosion.
Carbon Steel pipes and fittings are externally galvanized, but this galvanization does not provide permanent protection against corrosion.
The use of Carbon Steel pipes with PP coating (ø 12 – 108 mm) offers better protection against corrosion, while individual protection is needed for fittings. Carbon Steel parts are only suitable for use in permanently dry environments as humidity can lead to external corrosion over time.
The Carbon Steel system should be installed in a location with low humidity to prevent corrosion. If installed in areas exposed to high humidity, additional corrosion protection should be applied to the pipe and fittings to prevent external moisture and contact with building materials during and after installation.
Contact with building materials can lead to corrosion.
Carbon Steel components can be protected against outside corrosion by means of:
• Corrosion protection binding;
• Closed cell insulation or lagging;
• Avoiding installation in areas where the risk of corrosion is higher (e.g. Floor without cellar space underneath)
Carbon Steel components should not be subjected to permanent dampness. For this reason felt lagging or coverings are not approved, since they retain water.
The planner or the fitter carries the responsibility for the selection and installation of the corrosion protection measures.
*We do not stock this product but we can indent the materials from our Italian Manufacturer”