Control and optimization of fabrication processes contribute towards manufacturing better-quality products for a more significant market share. Optimization and control facilitate more efficient use of resources and reduce material and product cost consumption. Investing in induction brazing machines enables us to optimize the process in many folds. The induction brazing machine is equipped with control over a process where; induction heating is used to melt the filler metal to join two materials (metals/alloys) in a close-fitting space without melting the base material. Usually, flux is used in a process that is an anti-oxidizing solvent to prevent the brazed joint from oxidation. Filler metal is melted through induction heating and drawn between base metals through capillary action.
Induction brazing machines can form excellent quality water and airtight joints with less oxidation and much cleaner joints than flame brazing technology. This is why induction brazing is so popular. Due to its precise heating zone, induction brazing machines can join very small components, electronic components, and radio frequency collectors.
What are the main components of the induction brazing machine?
It is usually composed of the following:
- Induction Generators; used to produce electric power
- Proper Coils Design
- Feeder Units; can be automatic, semi-automatic, or manual
- Nitrogen Installation for protective gas atmosphere during brazing
- Water cooling of brazing chamber and fixtures
- Water re-cooling system
- Fixtures
- PLC control system
How different types of induction brazing machines are providing engineering solutions at the industrial level?
Three basic types of induction machines are discussed below;
This is a high-frequency magnetic induction copper tube pipe brazing machine that can be moved on location as needed.
Hardfacing alloys are commonly used in the tool industry for wearing. Conventionally, flame brazing was used to deposit the hard-facing alloy on stainless steel. According to research led by A. K. Chattopadhyay, the toolmaking process was modified by utilizing the induction brazing machine efficiently and effectively. A diamond grid with Ni-Cr was successfully brazed on the stainless steel.
The induction brazing machine provides temperature control which prevents the diamond from overheating. Shape distortion is also minimized through this joining technique.
The induction brazing of synthetic and natural diamond grits is carried out by heating at approximately 1080⁰C for 30 seconds without a vacuum or hydrogen furnace. A strong bond is created between the matrix and the diamonds.
Portable induction brazing machines are also used for their lightness, efficiency, and high-quality joint production.
- Semi-Automated induction brazing machine
A semi-automated machine obtains a perfect combination of speed, flexibility, and value. The operator will manage the assembly of components and application of flux, whereas the brazing of the component is automated. The automotive industry is looking for semi-automatic induction brazing machines to braze the pegs into gas filter caps for high production volume.
Induction brazing machines automate metal applications, improve product quality, yield lower labor costs, and reduce rejection rates by eliminating human error.
Manufacturers of Heating, ventilation & air conditioning system (HVAC systems) require different braze joints during fabrication. Induction brazing is used as energy efficient and high-production technology to produce approximately twenty-five thousand parts per month which allocate 30 seconds per part. Automated induction heating machines were utilized, which have a capacity of 16 sample holding positions on a turntable. The table can automatically slide in and out of the coil, increasing repeatability and productivity. Also, control over the process is accurate, leading to low production losses by setting the optimum power and temperature. The automatic induction brazing machine designed by FOCO INDUCTION can complete the induction brazing of a circular saw blade tip in 3-5 seconds.
What materials can be brazed by an induction brazing machine?
Various induction brazing machines are introduced worldwide, which are eligible to create excellent quality joints on different materials per any application’s requirement. Materials that can be brazed are stainless steel, steel, carbon steel, titanium, copper, silver, aluminum, Kovar, molybdenum, and cement.
1. Induction brazing of similar materials
Carbon steel gas filters have two separate induction brazed joints on either side of the filter, which requires heat zone precision. Titanium is brazed in a hydrogen environment in turbine blade fabrication.
Copper tubes are joined in each modular compressor assembly and have 7 to 8 induction brazed joints of various integration. This technology can braze several parts independent of size limitation. For example, copper cylinders to copper wire, copper section to the copper spacer, copper T pipes, and small copper wires are successfully induction brazed.
Aluminum tubes are brazed by using an induction brazing process to the flange (base) for batteries. The main purpose of utilizing this technology is to achieve optimized heat distribution to have a good filler flow without melting the component. Aluminum tubing is brazed with an aluminum receiver in less than 15 sec. Magnetic steel belts are also brazed through this technology.
2. Induction brazing of dissimilar materials
Different metals are also joined through this process, such as brass fittings to copper tubes for an HVAC system. A special cable composed of gold wire cladding with stainless steel and a glass conductor core shifted to induction brazing due to its reliability and safe technology. Although the productivity rate is low but shorter heating cycle can optimize the technology.
For instance, induction brazing machines are proficient in brazing various materials of different types. For example, stainless steel can be brazed to Kovar and to molybdenum, and alumina ceramic can be brazed to Kovar. Utilization of flux before brazing stainless steel to Kovar and molybdenum led to good quality joint. Also, cermet can be brazed with steel as well. In a research work led by Guoqin Huang, a diamond was brazed onto 1045 steel .
What is the utilization of induction brazing machines in different industries?
Induction brazing machines are facilitated in numerous fields, such as:
- Aerospace Industry: Hydraulic lines, turbine blades
- Automotive & Transportation: Heat exchangers, shafts, plates fittings, gas filter components, electrical vehicle batteries, valve assembly, brake lines etc.
- Electrical Engineering: Short-circuit rings
- Toolmaking Industry: Carbide cutting tips
- Home Appliance Industry: Copper wires
- Air Conditioning Industry: HVAC-system
- Fittings Industry: Carbide pins for high-pressure grinding rolls, brass and stainless steel couplers, Diverter valve
- Generator /Power Plant construction
- Manufacturing and Automation Industry
- Oil & Gas Industry: Special cables (stainless steel-gold-glass conductor core), high-pressure fuel lines, fuel fillers
It is an efficient technology that reduces energy costs, offers repeatability at an even higher production rate along with low maintenance and footprint, and eliminates operator variability. This technology allows the operator to run operations under already defined limits and to set more precise limits, ensuring quality, productivity, and profitability without compromising safety. Brazing machines can fit into the unique fabrication environment of numerous industries.
