This increase in efficiency means the same refrigerant capacity can be produced with smaller exchange surfaces at the condenser and evaporator, with an associated reduction in piping volume, i.e. a higher heat exchange efficiency means smaller systems and lower refrigerant charge. Important given that third generation HFC refrigerant blends such as R 410 A are […]
Aluminum alloys are classified according to their alloying elements. The Aluminum Association designations are listed in the table below: Designation System for wrought aluminum alloys Alloys series Description or major alloying element 1xxx 99.00% minimum Aluminum 2xxx Copper 3xxx […]
How to measure? In the case of heat exchangers, the surface area being fluxed must first be determined. For ease of calculation, the louvers on the fin can be ignored. The radius on the fin can also be ignored. Imagine then the fin pulled out of the heat exchanger and straightened out to form one […]
Brazing also offers the chance to change the design of heat exchangers by substituting round tubes with flat channels (microchannels) which offer improved heat transfer on both refrigerant and air sides for two reasons: better section/surface ratios, which affect the efficiency of heat exchange on the air and the refrigerant side; smaller surfaces in the […]
Brazing aluminium to copper is common in the refrigeration industry where copper tubes are brazed to aluminium roll-bond panels or tubes. To join aluminium and copper using brazing technology and standard NOCOLOK® Flux, flame brazing would be applicable (as well as using a low-melting flux with a low-melting filler metal). It is very similar to […]
One of the largest potentials to increase efficiency of heat exchangers lies within the heat-transfers: reducing condensing temperatures by 3 °K will improve overall system efficiency by approx. 10 % for a standard R 410 A air conditioning cycle. A minimization of the temperature difference between the air flows and the phase change temperatures of […]
NOCOLOK® Flux is the world’s most widely used flux for aluminium brazing in a controlled atmosphere. Well-proven in the automotive industry, NOCOLOK® Flux is also increasingly used for brazing aluminium coolers for air conditioning and refrigeration systems. In the well-known standard applications NOCOLOK®Flux is not corrosive. To improve the positive properties under extreme conditions even further, Solvay […]
NOCOLOK® Cs is a special mixture that is intended for brazing Al alloys with a higher Mg content. By adding Mg to the alloy (types 6000 or 3000) higher material- and pressure resistance as well as better machine processing is now given, compared with NOCOLOK® standard Flux which could tolerate only low Mg contents. During brazing, Mg […]
1. Have a clean surface 2. Heat the joint evenly to brazing Temperature 3. Choose the right brazing alloy for the job 4. Select the appropriate means of removing the oxide skin from the faying surfaces of the joint 5. Use a capillary gap of the appropriate size 6. Apply the brazing alloy to the […]