The most important performance advantages for CuproBraze are durability as well as size & efficiency. In addition, CuproBraze is clearly superior for applications that must withstand elevated temperatures without failure.
CuproBraze Products Are Durable
Durability is the main reason to use CuproBraze today. CuproBraze is at its best in heavy duty vehicles. Practical experience in very demanding applications since 2000 is the best merit you can refer to.
Brazing of copper and brass in a furnace at a temperature of 650 °C results in the formation of a strong joint (Picture on the right). Special anneal-resistant alloys insure that the radiator cores retain their strength despite exposure to high brazing or operating temperatures. When compared to competing materials, CuproBraze provides stronger, tougher joints, allowing for more durable products. After twisting the CuproBraze core returns to its original position (Picture below).
Thanks to strong brazed joints and the reduction of galvanic corrosion at the joints, heat exchangers made by the CuproBraze process are extremely rugged. Their excellent resistance to fatigue and corrosion, and good repairability, lead to a long service life in many applications.
CuproBraze Performs Better with regard to Size and Efficiency
Cores made from copper and brass can reduce more heat per unit volume than any other material system. CuproBraze offers tremendous cooling capacity in a small package. The overall thermal efficiency of a heat exchanger core depends on many factors such as:
- Thermal conductivity of fins and tubes
- Spacing, size, thickness and shape of fins
- Spacing, size, wall thickness and shape of tubes
- Velocity of the air passing through the core
Efficiency is readily calculated and measured. Heat-transfer simulations and wind tunnel testing verify that copper/brass cores offer the most efficient rejection of heat per unit volume. CuproBraze offers many significant advantages in terms of efficiency
- The same heat rejection from an aluminum radiator can be achieved with a smaller-sized core in a CuproBraze model. A significant reduction in frontal area and volume is typical for CuproBraze designs (picture).
- More airflow can be directed to other heat exchangers in the same vehicle.
- Less fan power needed. Less fan noise is created.
CuproBraze is Superior at Elevated Temperatures
The ability to withstand elevated temperatures is a crucial benefit. CuproBraze is qualified for use at high temperatures.
Aluminum heat exchangers simply cannot withstand high temperatures without a considerable loss in their mechanical properties. Aluminum alloys are “temperature challenged” above 200 ºC because of their low melting points. The yield strength of aluminum is severely compromised above 200 ºC. Problems with fatigue cracking are greatly exacerbated in aluminum at elevated temperatures.
On the other hand, copper and brass heat exchangers can operate at temperatures well above 250 ºC. Some cores can withstand temperatures of 290 ºC and above, which still are well below the melting point of copper and brass.
CuproBraze Excels in Heat-Exchanger Applications
CuproBraze excels with respect to critical performance criteria such as durability, size and efficiency. It is the manufacturing method of choice in practically every application calling for superior heat transfer in a compact space.
CuproBraze technology is well suited for these applications:
- Radiators
- Heaters
- Charge air coolers (CACs)
- Oil coolers
- CPU coolers. Inverter coolers in hybrid vehicles.
- Climate control systems. Copper is classified as antimicrobial material, meaning less odor in passenger compartment.
- Other heat transfer cores
The technology is ideal for vehicles and equipment such as:
- Radiators
- Heaters
- Charge air coolers (CACs)
- Oil coolers
- CPU coolers. Inverter coolers in hybrid vehicles.
- Climate control systems. Copper is classified as antimicrobial material, meaning less odor in passenger compartment.
- Other heat transfer cores
CuproBraze Is a Vital Technology for Clean Diesel Engines
New legislation in Europe, Japan and the United States aims at reducing emissions from diesel engines. These new laws call for a dramatic reduction in the oxides of nitrogen released from heavy-duty truck engines and off-road diesel engines.
Diesel engine manufacturers must develop engine technologies such as exhaust-gas recirculation to reduce the nitrogen oxides (NOx) released from diesel engines. These solutions invariably result in significantly higher operating temperatures, since engine designs must cope with additional heat rejection from exhaust gas coolers, radiators and charge air coolers (CACs).
CACs must be highly efficient and durable in order to meet stringent emissions regulations. Previously, most CACs were made of aluminum, but the tensile strength of aluminum declines rapidly at 150 ºC and repetitive thermal cycling between 150°C and 200 ºC substantially weakens the product.
To comply with the reduced emission standards, the industry expects the average inlet temperature to reach 300 ºC.
CuproBraze CACs can handle these elevated operating temperatures without need for precoolers. New CuproBraze charge air coolers cope easily with higher temperatures and the greater strength of brass can withstand high pressure. Already many companies have switched to CuproBraze charge air coolers, and high-volume production of CuproBraze CACs is a reality.
Higher operating temperatures also place greater cooling requirements on the radiators of on-road and off-road heavy-duty trucks. Many truck makers are switching to CuproBraze from soldered copper-brass to meet these needs.
CuproBraze Is Attractive in Terms of Total Lifecycle Cost
CuproBraze technology has many advantages that impact the bottom line, with respect to manufacturing and product. In fact, there are many ways to save with CuproBraze, including the following examples:
- CuproBraze can be automated. The use of semi-automated or automated assembly equipment can greatly reduce manufacturing costs compared to other labor-intensive manufacturing methods.
- CuproBraze is simple. Compact and able to withstand elevated temperatures and vibrations, a CuproBraze core may allow for lighter mounting hardware and space-saving design layouts.
- CuproBraze saves energy. Brazing temperatures can be ramped up faster. Because it takes less energy to heat copper than it does to heat aluminum, it takes less energy to braze each unit.
- CuproBraze allows for efficient economies of scale. Since the furnace and production line don’t need to be dedicated to just one product line, manufacturers can cater to the needs of the profitable niche and special orders markets.
- CuproBraze is flexible. The continuous belt furnace allows for quick product changeovers — even at high throughput rates.
- CuproBraze process does not include a fluxing stage, eliminating the need for a separate rinse step to remove the flux residues from the brazed product. No rinsing operation means no expensive treatment of discharge water. Moreover, CuproBraze does not use lead and other toxic chemicals in the manufacturing process.
- CuproBraze allows for one-shot brazing. The process can make a complete heat exchanger in the brazing furnace, thus eliminating separate operations for attaching components such as tanks and inlet and outlet fittings. One-shot brazing has been implemented into production scale in 2008.
- CuproBraze heat exchangers are repairable with lead-free solder in the plant or in the field, as well as with silver containing brazing alloys. Less scrap, fewer returns and more uptime in the field add up to savings for the manufacturer and the end user.
CuproBraze Is Ideal for Sustainable Development
In today’s world of regulations, forward-thinking manufacturers are taking the environment into account when they analyze costs.
The production of millions of heat exchangers per year significantly affects the allocation of natural resources on a global scale, yet the quality of life worldwide has been greatly improved by the use of off-road diesel engines, heavy-duty trucks and passenger cars.
Today, the concept of sustainable growth – that is, the improvement of conditions through the judicious use of natural resources – guides conservationists. Environmentally, the CuproBraze process has important advantages over other technologies. No fluxing stage is needed for brazing, and the process is free of lead and other toxic chemicals. CuproBraze heat exchangers are repairable both in production and operation, which means more efficiency, less downtime and less waste.
Furthermore, copper and brass are virtually 100 percent recyclable. Aluminum production uses more than twice as much electrical energy compared to copper production (i.e., 54 MWh per ton of aluminum versus 25 MWh per ton of copper). Carbon dioxide entering the atmosphere each year could be reduced by about one million tons by making heat exchangers from copper and brass instead of aluminum.
If all other criteria is equal, then CuproBraze should be chosen for the sake of the environment!
For more information about copper and the environment, please visit www.copperinfo.com.