ļ»æInduction Preheating Hot Rod Heading With IGBT Heating Units
Objective Heat a waspaloy rod to 1500ĀŗF (815.5ĀŗC) for hot headingĀ application Material Waspaloy rod 0.5ā (12.7mm)OD, 1.5ā (38.1mm) length,Ā ceramic liner Temperature 1500 ĀŗF (815.5ĀŗC) Frequency 75 kHz Equipment ā¢ DW-HF-Ā 20 kW induction heating system, equipped with aĀ remote workhead containing two 1.32Ī¼F capacitors for aĀ total of .66Ī¼F ā¢ An induction heating coil designed and developedĀ specifically for this application. Process A seven turn helical coil is used to heat the rod. The rod isĀ placed inside the coil and power is applied for two seconds providing enough heat to penetrate the inner core. An opticalĀ pyrometer is used for close loop temperature control and a ceramic liner is used so the rod does not touch the coil. Results/Benefits Induction heating provides: ā¢ Low pressure and minimal residual stress ā¢ Better grain flow and microstructure ā¢ Even distribution of heating ā¢ Improved production rates with minimal defects
Induction Brazing Carbide To Stainless Steel Shaft With IGBT Heating Units
Objective Brazing a cone shaped carbide to a stainless steel shaft for a digger Material Cone shaped carbide 1.12ā (28.4mm) dia, 1.5ā(38.1mm) tall,Ā stainless steel shaft 1.12ā (28.4mm) dia and various length, blackĀ brazing flux and braze shims Temperature 1500 ĀŗF (815 ĀŗC) Frequency 277 kHz Equipment ā¢ DW-UHF-10Ā kW induction heating system, equipped with a remoteĀ workhead containing two 1.0Ī¼F capacitors for a total of 0.5Ī¼F ā¢ An induction heating coil designed and developed specifically forĀ this application. Process A three turn helical coil is used to braze the carbide to the shaft. TheĀ steel shaft is fluxed and the braze shim placed on top. The carbideĀ tip is fluxed and placed on top of the shim, lining up the countersunkĀ hole in the carbide. The hole is not fluxed because the flux outgasesĀ and causes the carbide to build up pressure and attempt to repelĀ from the shaft. Power is applied for 85 seconds for the braze shim toĀ flow and make a good joint. DAWEIās customer has a customerĀ who is unhappy with the braze quality of their digger so ourĀ customer is looking for a better quality brazing process.Ā DAWEIāsĀ customer is very happy with the sample brazedĀ diggers and the help he received from the Ameritherm lab inĀ developing his brazing process. Results/Benefits Induction heating provides: ā¢ Rapid localized heating only where needed ā¢ Creates clean, controllable joints ā¢ Hands-free heating that involves no operator skill forĀ manufacturing ā¢ Even distribution of heating
High Frequency Induction Cap Sealing With IGBT heating units
Objective To heat an aluminum foil inside a plastic shampoo cap forĀ sealing Material 2.0ā diameter, plastic flip top cap, with a 0.9ā diameterĀ aluminum foil seal Temperature 250 – 300 ĀŗF (120 ā 150 Ā°C) Frequency 225 kHz Equipment DW-UHF-7.5 kW, induction heating system, equipped with aĀ remote heat station containing two 1.5 Ī¼F capacitors (totalĀ capacitance 0.75 Ī¼F). An induction heating coil designed and developed specificallyĀ for this application. Process A three-turn two-position helical coil is used to heat theĀ aluminum foil in a tunnel style assembly. Product (containers) passes easily under the induction coil. The assembly is locatedĀ such that the entire perimeter of the aluminum foil is heated uniformly. The container and cap is placed under the coil andĀ RF power delivered for 0.12 seconds. The aluminum foil heats and seals to the plastic of the cap. Results/Benefits This induction heating configuration fulfills the process requirements and: ā¢ uses a simple, economical coil design ā¢ increases throughput with a dual-position coil ā¢ delivers quality, consistent seals ā¢ offers a repeatable process, well-suited for automation
InductionĀ Heating Aluminum Foil For Cap Sealing with IGBT inductive heater
Objective An induction heater is used to heat a polymer laminatedĀ aluminum foil in 0.5 to 2.0 seconds. The heat produced in theĀ aluminum foil melts the polymer that bonds to the neck of aĀ plastic container. Material Aluminum foil, polyethylene, polypropylene, polyvinylchloride,Ā polystyrene, polyethylene terephthalate, styrene acrylonitrile Temperature 300 – 400 (ĀŗF), 149 – 204 (ĀŗC) Frequency 50 to 200 kHz Equipment DAWEIĀ solid-state induction powerĀ supplies operating between 1 & 10 kW at frequencies of 50-Ā 200 kHz. These units operate with remote sealing heads whichĀ allows the main power cabinet of the equipment to be locatedĀ away from the immediate production area. Distances of up toĀ 100 meters are possible. The microprocessor is used to control and protect the system and ensures that the optimal operatingĀ frequency is maintained at all times and that each container receives the same amount of heat energy from cycle to cycle. Process Two different types of aluminum foil laminates are available forĀ this application. The first assembly includes backing board/reseal, a wax layer, aluminum foil, and a heatseal filmĀ for supported systems (Figure 1). The second assemblyĀ includes a high temperature film, aluminum foil, and a heatsealĀ film for unsupported systems (Figure 2). The procedure is to fitĀ the foil membrane into the cap and to fit the cap to theĀ container after the product is filled. Results For the aluminum foil assembly as shown in Figure 1, heatĀ induced in the metallic foil by the induction coil almost instantaneously melts the polymer coating and the neck of theĀ container forming a hermetic seal between the heat seal film and the rim of the container. The heat also melts the waxĀ between the aluminum foil and the back board. The wax is absorbed into the back board. This results in an air tight bondĀ between the aluminum foil/membrane and the rim of the container, the back board is released and remains in the cap.
Process (contād) In the case of unsupported membranes in Figure 2, one side ofĀ the aluminum foil is coated with a heat sealable polymer filmĀ and this face that will be in contact with and sealed to theĀ container. The other side of the foil that will be in contact withĀ the cap has a higher melting-point film that prevents adhesionĀ of the aluminum to the cap allowing the end user to unscrewĀ the cap. Unsupported membranes are typically used where theĀ end user pierces the tamper evident membrane prior toĀ dispensing the product.Ā The aluminum foil acts as a vapor barrier preserving theĀ freshness of the product and prevents it from drying.
Shrink Fit Steel Gear onto Shaft With High Frequency Induction Heating Units
Objective Heat the bore of a hardened spur steel gear to shrink fit onto aĀ gear motor shaft. This is part of a chair for the disabled. Material Steel gear 2.5ā (63.5mm) OD, .75ā (19mm) ID x .625ā (16mm)Ā thick, temperature indicating paint Temperature 400 ĀŗF (204 ĀŗC) Frequency 300 kHz Equipment ā¢ DW-UHF-3.2 kW induction heating system, equipped with aĀ remote workhead containing two 0.66 Ī¼F capacitors for aĀ total of 1.32 Ī¼F ā¢ An induction heating coil designed and developedĀ specifically for this application. Process A four turn helical internal coil is used to heat the gear bore. The coil is inserted into the gear bore and power is applied forĀ 90 seconds to reach the required 400 ĀŗF (204 ĀŗC) and expand the gear bore. The gear is then placed on the shaft andĀ allowed to cool, creating the shrink fit between the gear and the shaft. Results/Benefits Induction heating provides: ā¢ No pre-heat cycle, heat is available on demand ā¢ Energy efficient, heats only the part, not the atmosphereĀ around it ā¢ Controlled, even distribution of heating ā¢ Faster production times
Induction Shrink Fitting Carbide Ring With IGBT Induction Heating Units
Objective Shrink fitting a carbide ring into a steel valve seat Material Steel valve seat 6ā (152.4mm) OD with 3ā (76.2mm) ID hole &Ā .75ā (19mm) thick, carbide ring Temperature 500 ĀŗF ( 260 ĀŗC) Frequency 85 kHz Equipment ā¢DW-HF-15kW induction heating system, equipped with aĀ remote workhead containing two 0.50 Ī¼F capacitors for aĀ total of 0.25 Ī¼F ā¢ An induction heating coil designed and developedĀ specifically for this application. Process A three turn helical coil is used to heat the steel valve seat. The steel valve seat is placed in the coil and heated for 50Ā seconds to enlarge the center hole & drop the carbide ring in for the shrink fitting process. Results/Benefits Induction heating provides: ā¢ Accurate and repeatable results ā¢ Ease of integration into existing production lines ā¢ Energy efficient, only heats the part, not the atmosphereĀ around it ā¢ Hands-free heating that involves no operator skill forĀ manufacturing ā¢ Even distribution of heating
Induction Shrink Fit Aluminum Shaft with IGBT induction heating systems
Objective Heat aluminum impeller blades to 200 ĀŗF (93 ĀŗC) and shrink fitĀ onto a shaft. Material Aluminum impeller blades with a .28ā (7.109mm) bore,Ā aluminum shaft Temperature 200 ĀŗF (93 ĀŗC) Frequency 255 kHz Equipment ā¢ DW-UHF-6W induction heating system, equipped with aĀ remote workhead containing one 1.0Ī¼F capacitor. ā¢ An induction heating coil designed and developedĀ specifically for this application. Process A split two turn helical coil is used to evenly heat the openingĀ on the impeller blade. The impeller blade is heated for 20Ā seconds to reach the 200 ĀŗF (93 ĀŗC). The impeller blades areĀ then removed from the coil & slipped over the shaft toĀ complete the shrink fitting application. Results/Benefits Induction heating provides: ā¢ Repeatable results ā¢ Reduced cycle time, lower consumables cost ā¢ Even distribution of heating
Inductioin Shrink Fitting Aluminum Pulley With IGBT Heating Units
Objective Heat aluminum pulley for insertion of an inner bearing for theĀ automotive industry Material Aluminum pulley 2.3ā (60mm) OD x 1.6ā (40mm) ID x 1āĀ (27mm) high and inner bearing 0.7ā (17.8mm) high x 1.6āĀ (40mm) dia Temperature 464 ĀŗF (240 ĀŗC) Frequency 283 kHz Equipment ā¢ DW-UHF-4.5kW induction heating system, equipped with aĀ remote workhead containing two 0.33Ī¼F capacitors for aĀ total of 0.66Ī¼F ā¢ An induction heating coil designed and developedĀ specifically for this application. Process A three turn helical coil is used to heat the aluminum pulley. The pulley is heated to 464 ĀŗF (240 ĀŗC) in 20 seconds toĀ expand the inner diameter and then the inner bearing isĀ inserted to form the completed part. Results/Benefits Induction heating provides: ā¢ Defined and controlled heat pattern ā¢ Process easily integrated into automated system ā¢ Even distribution of heating
Induction Shrink Fitting Assemble Connecting Rods With IGBT Heating Units
Objective Assemble connecting rods with a more accurate control of theĀ heat Material Rod has an OD of .9125ā (23.18mm), knuckle has an ID ofĀ .9125ā (23.18mm) with an interference of .0001ā (.0025mm).Ā Knuckle assembly is forged steel Temperature 400 ĀŗF (204 ĀŗC) Frequency 210 kHz Equipment ā¢ DW-UHF-Ā 3.5 kW induction heating system, equipped with aĀ remote workhead containing two 1.0Ī¼F capacitors for aĀ total of 0.5 Ī¼F ā¢ An induction heating coil, designed and developedĀ specifically for this application. Process A six turn helical coil is used to heat the connecting rod for 13Ā seconds. The coil is perpendicular to the axis of the bore toĀ promote even heating around the circumference. TheĀ connecting rod is then assembled with the piston for shrinkĀ fitting. Results/Benefits Induction heating provides: ā¢ More accurate control of heat vs a flame burner. Only heatsĀ knuckle, not the whole part. ā¢ Lower temperature used to prevent discoloring. ā¢ Increased productivity due to repeatability & ease ofĀ operation. A foot pedal & timer is used. ā¢ No product contamination.
Objective To use induction to prepare cast iron assemblies for shrink fitĀ assembly Material Customer supplied cast iron rocker arms of varying sizes Temperature 450 ĀŗF (232 Ā°C) Process Time 20 seconds Frequency 148 kHz Equipment DW-UHF-5.0 kW, 150-400 kHz solid state induction heatingĀ system, equipped with a remote heat station containing oneĀ 1.0Ī¼F capacitor An induction heating coil designed and developed specificallyĀ for this application. Process A four-turn helical coil heats the ring at one end of theĀ assembly. The coil is designed to concentrate the field towardsĀ the center of the assembly where the thermal mass is greatest. Across the heated ring, the coil presents a lighter field.Ā After heating, a pin is place within the ring and the assembly isĀ water quenched. The heat time varies from part to part but is less than 20Ā seconds. Results/Benefits Induction heating satisfies the needs of this process for: ā¢ rapid part heating ā¢ flexibility for parts of differing geometries ā¢ individual, series part heating, suitable for automation ā¢ a clean source of heat ā¢ even heat distribution
