Objective
The objective of the application test is induction brazing aluminum tubing to aluminum parts in less than 15 seconds. We have aluminum tubing and an aluminum “receiver”. The brazing alloy is an alloy ring, and has a flow temperature of 1030°F (554°C).
Equipment
DW-HF-15kw induction heating machine
[caption id="attachment_97" align="alignnone" width="267"]
induction heating machine HF-15[/caption]
Induction heating coil
Materials
• Aluminum tube: 0.167” (4.242mm) OD, 0.108” (2.743mm) ID
• Aluminum component: ID .1675” (4.255mm), depth .288” (7.315mm),
chamfer at top area is 0.2375” (6.033mm) ID max
• Braze alloy in the form of two-turn alloy ring
• Flux
Key Parameters
Temperature: 1030°F (554°C)
Power: 5 kW
Time: 14 seconds
induction heating machine HF-15[/caption]
Induction heating coil
Materials
• Aluminum tube: 0.167” (4.242mm) OD, 0.108” (2.743mm) ID
• Aluminum component: ID .1675” (4.255mm), depth .288” (7.315mm),
chamfer at top area is 0.2375” (6.033mm) ID max
• Braze alloy in the form of two-turn alloy ring
• Flux
Key Parameters
Temperature: 1030°F (554°C)
Power: 5 kW
Time: 14 seconds
Process:
Results/Benefits:
The 5 kW induction heating system requested by the customer, will meet the customer’s time requirements for induction brazing.


- The Aluminum component and tube were assembled together with the alloy ring. Flux was added.
- The part was positioned in the induction coil.
- Several tests were conducted with different cycle times to confirm the heating time for a good braze.
- At 15 seconds the assembly melted.
- At 14 seconds, we had success for brazing aluminum to aluminum, and a good quality braze joint was achieved.
Results/Benefits:
The 5 kW induction heating system requested by the customer, will meet the customer’s time requirements for induction brazing.
- Precise control of the time and temperature
- Power on demand with rapid heat cycles
- Repeatable process, not operator dependent
- Safe induction heating with no open flames
- Energy efficient heating



Induction Brazing Aluminum Pipes
Objective: Brazing two aluminum pipes simultaneously to an aluminum evaporator core
Material 2 aluminum pipes 0.72" (18.3mm) diameter, evaporator core 9.88" x 10.48" x 1.5" thick (251mm x 266.3mm x 38mm), braze rings
Temperature 610 ºF (321 ºC)
Frequency 250 kHz
Equipment • DW-UHF-20KW induction heating system, equipped with a remote workhead containing two 1.5μF capacitors for a total of 0.75μF • An induction heating coil designed and developed specifically for this application.
Process A four turn helical pancake coil is used to heat the 2 pipes simultaneously. Three braze rings are placed on each joint and power is applied for 90-100 seconds to create a leak proof joint on both pipes. Narrative • Customer is requiring a 40 seconds heat time for both brazes. In order to meet this requirement 3 units will be utilized to braze 2 joints each for a total of 6 joints in 90-100 seconds. The customer is currently using a flame process which can burn away the thin flange at the joint area and create scrap parts. By switching to induction for this application the customer is decreasing their scrap parts and also increasing their quality and production rate.
Results/Benefits Induction heating provides:
• Repeatable leak free joints
• Increased part quality, less scrap
• Hands-free heating that involves no operator skill for manufacturing
• Even distribution of heating
Brazing Aluminum to Copper Tubes with Induction
Objective: To heat an aluminum manifold to 1050 ºF (566 ºC) for a brazing application:
Material :
