NRF ARTICLE - BY ADAM GERTRUDA (NRF TECHNICAL SPECIALIST)

Not all radiators are the same > The difference between brazed and mechanically assembled radiators

“Choosing a is not always easy, because there are often a lot of different choices. Keep in mind that there can be a huge different between two parts, depending on the materials, technology and performance. By choosing the right radiator, you Adam Gertruda choose a high quality part with optimal performance and durability.” Technical Specialist

The (aftermarket) offer > The radiator > Temperature test > There are two types of radiators. The radiator is connected to the en- Minimum visible in the mechanically assembled radiator test. A mechanically assembled (usually gine with channels through which a li- cheap) radiator and a brazed radiator. quid (engine ) is pumped. The Both of these radiators are used by circulating coolant receives the com- car manufacturers. When replacing a bustion heat and has to cool down by radiator, the new radiator specificati- the radiator. The radiator has a series ons (material, technology and dimen- of thin tubes where the coolant flows sions) have to be equal or better than through. By a continuous air flow the the original part. Only in case when coolant is cooled down. This results in the replacement radiator is brazed a constant engine temperature and NRF compressor assembly line > and the original one was mechanically prevents the engine from overhea- assembled it is acceptable that the ting. The radiator is placed in the front core thickness is slightly smaller. This of the vehicle, often attached to other • The other type of radiator is the is because a brazed radiator has up to heat exchangers, such as the intercoo- mechanically assembled radiator. 60% more cooling performance. ler or condenser. The difference with a brazed one is the cost and energy saving production In case of a retrofit trailer hitch instal- The difference between brazed and method, because these radiators are lation and/or engine performance mechanically assembled radiators > not soldered. The tubes are always tuning it is recommend to check the A radiator consists of tubes with fins round. These round tubes are inserted radiator for possible replacement for a in between. The (hot) coolant passes throughout the fins pack. There always high performance brazed version. through the tubes. The fins provide will be a tiny gap between the tubes the heat transfer from the tubes into and fins. This automatically results in a Engine cooling basics > the air stream. There are two ways in much lower (up to 60%!) heat transfer When an engine is in use, it produces a which radiators are produced: compared with a brazed radiator. lot of friction and heat. Temperatures may increase to more than 1.500 °C. • In a brazed radiator the fins and tu- Final conclusion > The engine (parts) that are subjected bes are brazed in an oven. This creates If a vehicle engine originally has been to such temperatures must be effec- a metal connection. Due to this brazed equipped with a mechanically assem- tively cooled to prevent overheating. connection an optimal heat transfer is bled radiator, then the same type can If the engine temperature should be being created. The tubes of this type be used for repair. If the original radi- too low, fuel economy will suffer and of radiator are often flattened. This ator was a brazed radiator, then the emissions will rise. The engine cooling creates a larger cooling surface. NRF assembly of a brazed radiator is highly system keeps the engine at a constant radiators are soldered according the recommended! It is likely that the en- temperature. An essential part is the Nocolok® brazing technology. gine can operate in such a thermal radiator. stress condition where the mechani- cally assembled radiator is unable to Mechanically assembled radiator > Brazed radiator > provide an optimal cooling. Round tubes, no fixed connection between Flattened tubes, brazed connection between tubes and fines. Lower cooling performance. tubes and fines. High cooling performance. A brazed radiator is usually a bit more expensive than a mechanically assem- bled radiator, but is a safer, stress-free and long-term solution. NRF has a pro- duct range of more than 3.000 brazed radiators.

The art of cooling >

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