Technologies

Brazing Brass Pipe With Induction

Brazing Brass Pipe With Induction

Objective: Block is heated to 1400Ā°F to braze trap tube to assembly

Material :brass block and pre-formed tubes braze pre-forms

Temperature: 1400 ĀŗF (760Ā°C)

Frequency: 350 kHz

Equipment DW-UHF-10KW induction heating system including ā€¢ Coil: custom-designed 2-turn split-helical ā€¢ Workhead: contains two 1.0Ī¼F capacitors (0.5 Ī¼F total)

Process The brass parts, braze pre-form and flux are assembled and located within the custom-designed coil. Induction heating of the joint is accomplished in 45 seconds.

Results/Benefits

Economy: induction heats only the material within the coil; no energy is wasted heating the surrounding materials and air; no flame or gasses required for heating Control: process lends itself to the use of braze pre-forms; process easily adapted to automation

Efficiency: energy is expended only during the joint formation

 

Brazing Copper to Brass Pipe With Induction

Brazing Copper to Brass Pipe With Induction

Objective: Brazing several brass and copper assemblies used in water faucets Material braze, white flux

Temperature 1350 Ā°F 730Ā°C

Frequency 200 or 280 kHz (coil dependant)

Equipment DW-UHF-10KW induction heating system, remote work head with two 1Ī¼F capacitors and a 3-turn helical coil

Process: Three helical coils are used separately to braze a range of provided parts. Parts are assembled with flux and a braze alloy and then heated. The heat time varies from part to part with large parts taking less than 3 minutes and, the smaller parts heated in less than 20 seconds. After heating the parts are quench-cooled.

Results/Benefits

Repeatability: the inherent precision of induction heating supports a process which is highly repeatable.

Economy: the process allows for the use of higher temperature braze alloy than a flame process

Brazing Brass To Copper With Induction

Brazing Brass To Copper With Induction

Objective: To braze brass end-connectors to copper tubes used in aircraft assembly air lines Material brass end connectors, copper tubes of different diameters

Temperature 1400 ĀŗF 750Ā°C

Frequency 350 kHz

Equipment DW-UHF-4.5KW induction heating system, including a three turn helical induction coil using two 0.33Ī¼F capacitors (total 0.66Ī¼F)

Process For smaller diameter parts, flux is applied to the entire part and the copper tube to brass joint is assembled using brazing preforms (allowing for the same amount of braze in each joint). The assembly is placed in the coil and heated for 20-30 seconds reaching a temperature of 1400Ā°F. For larger copper tube assemblies, the same process is used, but the braze alloy is stick-fed to the joint to prevent the alloy from flowing out of the joint. A foot switch control is recommended to enable better control of the process.

Results/Benefits

Economy: Power is consumed during the heating only

Consistency: the results of braze joints are repeatable and uniform

Brazing Carbide Tool Tips With Induction

Brazing Carbide Tool Tips With InductionĀ 

Objective: Attaching carbide cutters to a steel meat cutter impeller

Material carbide blocks; steel shank fitting

Temperature 1400 Ā°F (760 Ā°C)

Frequency 300 kHz

Equipment DW-UHF-30KW induction heating systems including: Induction heating coil Workhead: two-cap 1.0Ī¼F (Total 0.5 Ī¼F) Process The entire part is placed in a five-turn helical coil, the power is applied until the part is heated to the required temperature and a uniform heat pattern is achieved. The coil allows for easy fixturing and uniformity of heating between the carbide and the steel shank for a premium braze joint.

Results/Benefits

Precision: Due to the size of the induction coil, the process allows for precise placement of the carbides on the steel shanks

Economy: Power is consumed only during the heat cycle

Repeatability: joint quality is maintained in this repeatable process

Brazing Brass to Aluminum with Induction

Brazing Brass to Aluminum with Induction

Objective: Copper ‘tees’ and ‘ells’ are to be brazed to the aluminum body of a refrigeration valve

Material customer’s valve copper fittings braze

Temperature 2550 ĀŗF (1400Ā°C)

Frequency 360 kHz

Equipment DW-UHF-10KW induction heating system including a workhead containing two 1.5Ī¼F capacitors (total 0.75Ī¼F) and a three-turn helical coil

Process The valve is placed inside the coil and RF power is applied until the part is heated to the required temperature and the braze is seen to flow into the joint. Two tube sizes were run using the same induction system settings with differing cycle times.

Results/Benefits ā€¢ energy is applied only to the zone to be heated ā€¢ heating of the joint/braze is uniform and repeatable

Brazing Carbide To Steel With Induction

Brazing Carbide To Steel With InductionĀ 

Objective: Braze carbide rotary file assemblies with uniform concentricity in an aerospace application

Material :

ā€¢ Carbide blank

ā€¢ High speed steel shank

ā€¢ Temperature indicating paint

ā€¢ Braze shim and black flux

Temperature 1400Ā°F (760Ā°C)

Frequency 252 kHz

Equipment DW-UHF-10kw induction heating system, equipped with a remote heat station containing two 0.33 Ī¼F capacitors (total 0.66 Ī¼F) An induction heating coil designed and developed specifically for this application.

Process A multi-turn helical coil is used. The part is heated to determine the time required to reach the desired temperature and required heat pattern. It takes approximately 30 – 45 seconds to reach 1400Ā°F (760Ā°C) depending on the various part sizes. Flux is applied to the entire part. A braze shim is sandwiched between the steel shank and carbide. Induction heating power is applied until the braze flows. With proper fixturing, concentricity of the part can be achieved.

Results/Benefits ā€¢ Repeatable, consistent precise heat.

Induction Aluminum Brazing Process

Induction Aluminum Brazing Process

Induction aluminum brazing is becoming more and more common in industry. A typical example is brazing various pipes to an automotive heat exchanger body. Aluminum requires a lot of energy to heat using induction and its thermal conductivity is 60% compared to copper. Coil design and time for the heat to flow is critical in a successful induction brazing process for aluminum parts. Recent advances in lower temperature aluminum braze materials have allowed induction to effectively replace flame and furnace heating in high volume brazing of aluminum assemblies.

Successful Induction brazing of aluminum parts requires the correct braze filler material for the aluminum alloy used in the parts and the correct flux for the braze alloy. Braze filler manufacturers have their own proprietary aluminum braze alloys and flux materials that work with their alloys.

Brazing Aluminum Pipes Assembly With Induction

Brazing Aluminum Pipes Assembly With Induction

Objective: Braze an aluminum assembly to 968 ĀŗF (520 ĀŗC) within 20 seconds

Material : Customer supplied 1.33″ (33.8 mm) O.D. aluminum tube and aluminum mating part ,Aluminum braze alloy

Temperature: 968 ĀŗF (520 ĀŗC)

Frequency 50 kHz

Equipment: DW-HF-35KW,30-80 kHz induction heating system equipped with a remote heat station containing one 53 Ī¼F capacitor A two-position helical induction heating coil designed and developed specifically for this application.

Process: Braze material was applied between the tubing and the mating part. The assembly was placed inside the coil and heated for approximately 40 seconds. With a two-position coil, two parts can be heated simultaneously, which means one part would be completed every 15-20 seconds. Braze material was stick fed, which created a good joint. The heating time with two parts being heated simultaneously meets the client’s objective, and represents a significant improvement in regards to speed over using a torch.

Results/Benefits

  • Speed: The recommended approach cut their heating time in half when compared to using a torch
  • Part quality: Induction heating is a repeatable method with more consistency than a torch can generally deliver
  • Safety: Induction heating is a clean, precise method that does not involve an open flame like a torch, which results in a safer work environment

Brazing Aluminum to Copper Tubes with Induction

Brazing Aluminum to Copper Tubes with Induction

Objective: To heat an aluminum manifold to 1050 ĀŗF (566 ĀŗC) for a brazing application:

Material :

  • Cu tubes (3/4″/19mm)
  • Cu tubes (5/8″/15.8mm)
  • AI tubes (3/8″/9.5mm)
  • AI manifold (5/8″/15.8mm)
  • AI manifold (3/4″/19mm)
  • Lucas-Milhaupt Handy One alloy 30-832
  • Braze wire

Temperature 1050 ĀŗF (566 ĀŗC)

Frequency 260 kHz

Equipment DW-UHF-10KW 150-500 kHz induction heating system equipped with a remote heat station containing two 1.5 Ī¼F capacitors.

  • A two-turn oval helical induction heating coil designed and developed specifically for the aluminum assembly
  • A five-turn helical induction heating coil designed and developed specifically for brazing the Cu tubes to AI joint assembly

Process Braze : pre-forms were designed to fit the aluminum tubes. Then the four aluminum tubes were placed into the manifold and the assembly was inserted into the coil. The assembly was heated for approximately 70 seconds, at which point it reached the targeted temperature and braze flowed. For the Cu tubes, a braze pre-form was also designed for them, wound around the tubes, and the assembly was placed inside the coil. The heating cycle time was approximately 100 seconds. Some joints required stick feeding of braze to fill the entire joint area due to the braze wire size. If the cycle time was lengthened, the need for stick feeding would be eliminated.

Results/Benefits: Precise, repeatable heating:

  • The client wanted more precise and repeatable heating than a torch could deliver, which induction was able to achieveĀ .
  • Temperature control: Induction allows for superior temperature control when compared to other methods, including a torch, which the client desired

 

Induction Brazing Aluminum Pipes

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 ĀŗF (321 ĀŗC)

Frequency 250 kHz

Equipment ā€¢ DW-UHF-20KW induction heating system, equipped with a remote workhead containing two 1.5Ī¼F capacitors for a total of 0.75Ī¼F ā€¢ 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 ā€¢ 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:
ā€¢ Repeatable leak free joints
ā€¢ Increased part quality, less scrap
ā€¢ Hands-free heating that involves no operator skill for manufacturing
ā€¢ Even distribution of heating

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