Exchangers
From cooling devices to lightweight structural work: RGR develops the right solution for you
RGR specialises in designing – internally or based on the client’s drawing – heat exchangers, in particular air to air and air to water heat exchangers, industrial/electric fans and components in the field of mid to lightweight industrial structural work. Heat exchangers and fans are mainly manufactured for electric motors of great power, which are used in steel plants and lifting and moving systems.
Specialists in manufacturing heat exchangers
RGR offers two types of heat exchangers: air to air heat exchangers and air to water heat exchangers. Both of them operate in closed circuit and are suitable whenever the electric machine to be cooled down is located in a room characterised by the presence of conductive powders, flammable gases, water and other elements which, by seeping into such machine, could seriously damage it.
Heat exchangers are characterised by the presence of two fluids that circulate and cross, obviously without coming into direct contact with each other: the first one is air, which is inside the motor – exchanger unit; the second one can be air, in case of air to air exchangers, or water, in case of air to water exchangers.
In air to air exchangers, the coolant is represented by the ambient air that is sucked by an attached electric fan and forced to circulate inside the heat exchange tubes, which can be made of aluminium or stainless steel; the internal air moved by another electric fan, after having gone through the possible filter, licks the surface of this tube bundle: it is during this phase that the heat exchange between the internal hot air and the external colder air takes place. After having taken the heat out of the internal air, such external air is expelled towards the outside.
AIR TO AIR EXCHANGERS
In air to air exchangers, the coolant is represented by the ambient air that is sucked by an attached electric fan and forced to circulate inside the heat exchange tubes, which can be made of aluminium or stainless steel; the internal air moved by another electric fan, after having gone through the possible filter, licks the surface of this tube bundle: it is during this phase that the heat exchange between the internal hot air and the external colder air takes place. After having taken the heat out of the internal air, such external air is expelled towards the outside.
Different solutions can be adopted when designing air to air exchangers depending on the different needs: instead of being sucked, the external air can be pushed through the tubes; fans directly moved by the electric machine can be used; or the convective motion can be used for the circulation of one of the two fluids; and many more options.
In order to make sure that all components work correctly, exchangers are fitted with the following devices (other ones can also be added):
- External air electric fan pressure switch;
- Internal air electric fan pressure switch;
- Internal air electric fan thermostat.
The degree of protection that air to air heat exchangers are able to offer ranges from IP44 to IP55; to obtain an even higher rating, exchangers can be internally pressurised by adopting particular measures.
In the case of air to water exchangers, the operation of which is similar to the one of air to air exchangers, the colder external fluid consists in water that is made circulate inside the radiator by means of the specific client’s pumps. The water used may contain additives and impurities; the use of seawater is also allowed. According to the water quality, the material that will better resist corrosion is identified for the tube bundle. As regards the radiator, it can be placed vertically or horizontally; it can be fitted with a system that enables the internal cleaning of tubes or with a double tube (lined) in case of more critical installations.
In the case of air to water exchangers, the operation of which is similar to the one of air to air exchangers, the colder external fluid consists in water that is made circulate inside the radiator by means of the specific client’s pumps. The water used may contain additives and impurities; the use of seawater is also allowed. According to the water quality, the material that will better resist corrosion is identified for the tube bundle. As regards the radiator, it can be placed vertically or horizontally; it can be fitted with a system that enables the internal cleaning of tubes or with a double tube (lined) in case of more critical installations.
In order to make sure that all components work correctly, air to water exchangers are fitted with the following devices (other ones can also be added):
- Electric fan air pressure switch;
- Electric fan air thermostat;
- Cooling battery condensate level indicator.
The degree of protection that air to water heat exchangers are able to offer ranges from IP44 to IP55; to obtain an even higher rating, exchangers can be internally pressurised by adopting particular measures.