In the 70’s a few companies tried their hand at making outdoor coils using all aluminum, environmental corrosion turned out to be a conquering opponent. Only one company had success, which was Trane Company, due to a very cleaver design, where the condensing tube is covered with glue an additional piece of aluminum. This additional piece is sacrificed to the environment, allowing the primary tube to stay in tack. Trane patented the process in details making it extremely hard to duplicate.
In a residential air conditioning unit, there are two coils and evaporator coil, indoor and a condenser coil, outdoor. The outdoor coil is approximately 3 times larger than the indoor, hints the outdoor coil has more metal in it. This is where the industry …show more content…
The average price for copper in 2011 was $4.00 per pound, from the high of $4.49 to the low of $3.43. 2010 the average price was .343 per pound.
Aluminum is three time lighter that copper. Picking a 3-ton coil as an example there is approximately 48 pounds of copper hairpin material in a unit, conversely, only approximately 16 pounds of aluminum. In in the 80’s the cost differential was only 43% or a $22 savings per coil. In 2011, the differential was 79% or $177 per coil.
ATI embarked on the development of fabricating aluminum brazed assemblies. We soon learned that making an aluminum braze joint was considerably more difficult that a copper braze joint. Due to this fact the industry placed a small amount of copper tube at the end of the assembly so the installer could make a copper to copper joint in place of a copper to aluminum joint. Now that was a head scratcher for some time. Making a copper to aluminum joint using brazing alloy was the hurdle and a tall one at that. The challenge is aluminum melts at approximately 1,100˚ and copper at 1981˚. A new type of brazing alloy was developed for this task, but it melts at 850˚. Using humans for this process problematic, so we develop a robotic method. The process development, that is developing methods to braze aluminum headers, took ATI a little over two years to
In a residential air conditioning unit, there are two coils and evaporator coil, indoor and a condenser coil, outdoor. The outdoor coil is approximately 3 times larger than the indoor, hints the outdoor coil has more metal in it. This is where the industry …show more content…
The average price for copper in 2011 was $4.00 per pound, from the high of $4.49 to the low of $3.43. 2010 the average price was .343 per pound.
Aluminum is three time lighter that copper. Picking a 3-ton coil as an example there is approximately 48 pounds of copper hairpin material in a unit, conversely, only approximately 16 pounds of aluminum. In in the 80’s the cost differential was only 43% or a $22 savings per coil. In 2011, the differential was 79% or $177 per coil.
ATI embarked on the development of fabricating aluminum brazed assemblies. We soon learned that making an aluminum braze joint was considerably more difficult that a copper braze joint. Due to this fact the industry placed a small amount of copper tube at the end of the assembly so the installer could make a copper to copper joint in place of a copper to aluminum joint. Now that was a head scratcher for some time. Making a copper to aluminum joint using brazing alloy was the hurdle and a tall one at that. The challenge is aluminum melts at approximately 1,100˚ and copper at 1981˚. A new type of brazing alloy was developed for this task, but it melts at 850˚. Using humans for this process problematic, so we develop a robotic method. The process development, that is developing methods to braze aluminum headers, took ATI a little over two years to