Section radiator are made by soldering copper collector and copper pipe, pressure-tested aluminum frame that provides high heat transfer plates (heat transfer coefficient of iron – 50, Steel – 58, Al – 220, Copper – 410). In contact with the coolant (water) is only a copper collector, aluminum elements are not in contact with water, thanks to a radiator excluded the possibility of electrochemical reactions (not required for such reactions electrolyte). Thus, the resistance is determined by the radiator anti-corrosion properties of copper collectors, practical life which in a closed system is several decades.
In copper pipes is much lower coefficient of roughness (Rm = 2 * 10-6) than that of steel (Rm = 200 * 10-6) and even than that of polymer (Rw = 8 * 10-6) pipes. This increases their capacity in terms of “dirty” domestic heating systems and helps to avoid “overgrown” pipe radiator.
The copper heatsink is not afraid of freezing water by the plasticity of copper, for the same reason, the radiator water hammer resistant to 60 atm.
“Thanks” to various contaminants in our water, and in particular chlorine on the inner wall of the tube – after about 100 hours of operation – a thin but durable flying tenor, with the formation of the radiator becomes virtually invulnerable.
Bi design showed very good results: devices can withstand prolonged stress high blood pressure, are resistant to hydro-and pnevmoudaram and at the same time have a high emissivity. They are designed for working pressure up to 20 atm and hydrostatic testing – up to 30 atm, the pressure of destruction – more than 60 atm, which allows for bimetallic radiators for heating of flats.