Technologies

  • Induction Curing Heating of Organic Coating

Induction Curing Heating of Organic Coating

Induction Heating is used to cure organic coating such as paint on metallic substrates by generating heat with in the subtract .By this mean curing occurs from within minimizing the tendency for formation of coating defects . A typical is application is drying of paint on sheet metal.
Induction heating of metal parts to adhesive induction curing temperatures is utilized in a many automotive processes, such as the use of thermosetting adhesives to produce clutch plates, brake shoes and auto bumper components. Shafts are typically bonded to the squirrel cage rotors in the manufacture of small motors. In copying machines, plastic components are adhesively bonded to aluminum rotors; a thermoplastic glue is used to hold foam rollers on metal shafts. Once the rollers wear out, the shaft is heated and the foam replaced.
Modern induction heating can solve many of these problems. Heating with induction provides reliable, repeatable, non-contact and energy-efficient heat in a minimal amount of time, so that the curing process can be completed with minimal energy and time. Improved temperature ramping cycles can be achieved with computer control of the solid state power supply. To eliminate extra steps for loading and unloading ovens, induction heat stations can be incorporated into a production line. Finally, induction heating can be performed in extremely clean environments, vacuum conditions or special atmospheres, allowing for unique curing solutions.

Although induction heating is normally used with metals or other conductive materials, plastics and other non-conductive materials can often be heated very effectively by using a conductive metal susceptor to transfer the heat. Typical RF power supplies for induction curing applications range from 4 to 60kW, depending on the parts and application requirements.

  • induction preheating copper rod

Induction preheating copper rod for hot forging

In order to want to improve safety and productivity, and reduce energy costs, by using induction instead of resistive heating. To maximize productivity, they want to be able to heat 3 brass rods at a time to 780° C within 25 seconds. For this application test, we are only heating one rod, so our goal is to heat the single rod to 780° C within 25 seconds with less than 45 kW of power. This will ensure that when heating 3 rods, that the 110 kW system will meet the production requirements.

Equipment
DW-HF-70kW Induction Heating Power Supply, operating between 10-50 kHz

Materials
• Brass rod
• Custom coil, 10 turns, D=50mm, designed and manufactured by DaWei Induction Power Technologies for this specific application – capable to heat 3 rods at a heat cycle.

Key Parameters
Temperature: 780° C
Power: 70 kW
Voltage: 380 – 480 V
Time: 24 sec
Frequency: 32 kHz

Process:

  1. The DW-HF series Power Supply was connected to the DW-HF-70kw Heat Station.
  2. The custom Coil was attached to the Heat Station.
  3. The Brass rods were placed inside the Coil.
  4. The Power Supply was turned on.
  5. The DW-HF series operating at 20 kW was able to successfully heat the single brass rod within 24 seconds, which was less than the 25 second time requirement established for the test. Three brass rods are expected then to heat within 25 seconds with approximately 60 kW of power (3 rods will be 3x the load and 3x the power). The 90 kW Induction system will therefore meet the customer’s requirements.

Results/Benefits:

Induction preheating provides:

  • Faster heating cycles
  • The process is safer than the flame heating
  • Technology without pollution, clean and safe

 

  • induction heating principle

A source of high frequency electricity is used to drive a large alternating current through a induction coil. This induction heating coil is known as the work coil. See the picture opposite.
The passage of current through this induction heating coil generates a very intense and rapidly changing magnetic field in the space within the work coil. The workpiece to be heated is placed within this intense alternating magnetic field.
Depending on the nature of the workpiece material, a number of things happen…
The alternating magnetic field induces a current flow in the conductive workpiece. The arrangement of the work coil and the workpiece can be thought of as an electrical transformer. The work coil is like the primary where electrical energy is fed in, and the workpiece is like a single turn secondary that is short-circuited. This causes tremendous currents to flow through the workpiece. These are known as eddy currents.
In addition to this, the high frequency used in Induction Heating applications gives rise to a phenomenon called skin effect. This skin effect forces the alternating current to flow in a thin layer towards the surface of the workpiece. The skin effect increases the effective resistance of the metal to the passage of the large current. Therefore it greatly increases the induction heating effect of the induction heater caused by the current induced in the workpiece.

induction_heating_principle

Magnetic Induction Heater  is a process equipment which is used to melt,braze,forge,bond,heat treating,harden or soften metals or other conductive materials. For many modern manufacturing processes, Magnetic induction heating equipment offers an attractive combination of speed, consistency and control.The basic principles of magnetic induction heating have been understood and applied to manufacturing since the 1920s. During World War II, the technology developed rapidly to meet urgent wartime requirements for a fast, reliable process to harden metal engine parts. More recently, the focus on lean manufacturing techniques and emphasis on improved quality control have led to a rediscovery of induction technology, along with the development of precisely controlled, all solid state induction power supplies.

Magnetic Induction Heater relies on the unique characteristics of induction heating radio frequency (RF) energy – that portion of the electromagnetic spectrum below infrared and microwave energy. Since heat is transferred to the product via electromagnetic waves, the part never comes into direct contact with any flame, the inductor itself does not get hot, and there is no product contamination. When properly set up, the process becomes very repeatable and controllable.

Main Characteristics:
   1.IGBT module and soft switiching inverting technologies are as in the production of the generator,higher reliability can be do. 
   2. Small and portable ,compared with SCR controlled machine only 1/10 working space is needed.
3.  High efficiency to save energy,high efficiency and power far can be maintained
   4.  The generator is adatable in a large frequency range from 1KHZ to 1100KHZ,installation can be done very easily according to our manual.  
     5. 100%duty cycle ,continuous working ability at maximum power.  
     6. Constant power or constant voltage control mode.
     7. Display of output power,output frequency,and output voltage.
Series
Model
Input power Max
Input current Max
Oscillate frequency
Input Voltage
Duty cycle
M
.
F
.
DW-MF-15 Induction Generator
15KW
23A
1K-20KHZ
According to the application
3*380V
380V±20%
100%
DW-MF-25 Induction Generator
25KW
36A
DW-MF-35Induction Generator
35KW
51A
DW-MF-45 Induction Generator
45KW
68A
DW-MF-70 Induction Generator
70KW
105A
DW-MF-90 Induction Generator
90KW
135A
DW-MF-110 Induction Generator
110KW
170A
DW-MF-160 Induction Generator
160KW
240A
DW-MF-45 Induction Heating Rod Forging Furnace
45KW
68A
1K-20KHZ
3*380V
380V±20%
100%
DW-MF-70 Induction Heating Rod Forging Furnace
70KW
105A
DW-MF-90 Induction Heating Rod Forging Furnace
90KW
135A
DW-MF-110 Induction Heating Rod Forging Furnace
110KW
170A
DW-MF-160 Induction Heating Rod Forging Furnace
160KW
240A
DW-MF-15   Induction Melting Furnace
15KW
23A
1K-20KHZ
3*380V
380V±20%
100%
DW-MF-25   Induction Melting Furnace
25KW
36A
DW-MF-35   Induction Melting Furnace
35KW
51A
DW-MF-45   Induction Melting Furnace
45KW
68A
DW-MF-70   Induction Melting Furnace
70KW
105A
DW-MF-90   Induction Melting Furnace
90KW
135A
DW-MF-110 Induction Melting Furnace
110KW
170A
DW-MF-160 Induction Melting Furnace
160KW
240A
DW-MF-110 Induction Hardening Equipment
110KW
170A
1K-8KHZ
3*380V
380V±20%
100%
DW-MF-160Induction Hardening Equipment
160KW
240A
H
.
F
.
DW-HF-04 Series
DW-HF-4KW-A
4KVA
15A
100-250KHZ
Single phase 220V
80%
DW-HF-15 Series
DW-HF-15KW-A
DW-HF-15KW-B
15KVA
32A
30-100KHZ
Single phase 220V
80%
DW-HF-25 Series
DW-HF-25KW-A
DW-HF-25KW-B
25KVA
23A
20-80KHZ
3*380V
380V±20%
100%
DW-HF-35 Series
DW-HF-35KW-B
35KVA
51A
DW-HF-45 Series
DW-HF-45KW-B
45KVA
68A
DW-HF-60 Series
DW-HF-60KW-B
60KVA
105A
DW-HF-80 Series
DW-HF-80KW-B
80KVA
130A
DW-HF-90 Series
DW-HF-90KW-B
90KVA
160A
DW-HF-120 Series
DW-HF-120KW-B
120KVA
200A
U
.
H
.
F
.
DW-UHF-3.2KW
3.2KW
13A
1.1-2.0MHZ
Single phase220V
±10%
100%
DW-UHF-4.5KW
4.5KW
20A
DW-UHF-045T
4.5KW
20A
DW-UHF-045L
4.5KW
20A
DW-UHF-6KW-I
6.0KW
28A
DW-UHF-6KW-II
6.0KW
28A
DW-UHF-6KW-III
6.0KW
28A
DW-UHF-10KW
10KW
15A
100-500KHZ
3*380V
380V±10%
100%
DW-UHF-20KW
20KW
30A
50-250KHZ
DW-UHF-30KW
30KW
45A
50-200KHZ
DW-UHF-40KW
40KW
60A
50-200KHZ
DW-UHF-6, 0KW
60KW
90A
50-150KHZ

Induction_heating_catalogue.pdf

Induction Brazing Machine&Soldering Equipment
Main characteristics:
    1.  IGBT module and inverting technologies of the first generation been used.
    2.  Simple structure and light weight and easy for maintenance.
    3.  Simple to operat ,afew minutes is enough to learn it.
    4.  Simple to install,installation can be done by unprofessional person very easily.
    5.  advantages of the model with timer,the power and the operatingtime of the heating period and the rain period  can be preset repectively,to realize a simple heating curve,this model is suggested to use for batch production to improve the repeatability.
   6.   The separated models are designed to fit the dirty surrounding of some cases.
Specifications
Series
Model
Input power Max
Input current Max
Oscillate frequency
Input Voltage
Duty cycle
M
.
F
.
DW-MF-15 Induction Generator
15KW
23A
1K-20KHZ
According to the application
3*380V
380V±20%
100%
DW-MF-25 Induction Generator
25KW
36A
DW-MF-35Induction Generator
35KW
51A
DW-MF-45 Induction Generator
45KW
68A
DW-MF-70 Induction Generator
70KW
105A
DW-MF-90 Induction Generator
90KW
135A
DW-MF-110 Induction Generator
110KW
170A
DW-MF-160 Induction Generator
160KW
240A
DW-MF-45 Induction Heating Rod Forging Furnace
45KW
68A
1K-20KHZ
3*380V
380V±20%
100%
DW-MF-70 Induction Heating Rod Forging Furnace
70KW
105A
DW-MF-90 Induction Heating Rod Forging Furnace
90KW
135A
DW-MF-110 Induction Heating Rod Forging Furnace
110KW
170A
DW-MF-160 Induction Heating Rod Forging Furnace
160KW
240A
DW-MF-15   Induction Melting Furnace
15KW
23A
1K-20KHZ
3*380V
380V±20%
100%
DW-MF-25   Induction Melting Furnace
25KW
36A
DW-MF-35   Induction Melting Furnace
35KW
51A
DW-MF-45   Induction Melting Furnace
45KW
68A
DW-MF-70   Induction Melting Furnace
70KW
105A
DW-MF-90   Induction Melting Furnace
90KW
135A
DW-MF-110 Induction Melting Furnace
110KW
170A
DW-MF-160 Induction Melting Furnace
160KW
240A
DW-MF-110 Induction Hardening Equipment
110KW
170A
1K-8KHZ
3*380V
380V±20%
100%
DW-MF-160Induction Hardening Equipment
160KW
240A
H
.
F
.
DW-HF-04 Series
DW-HF-4KW-A
4KVA
15A
100-250KHZ
Single phase 220V
80%
DW-HF-15 Series
DW-HF-15KW-A
DW-HF-15KW-B
15KVA
32A
30-100KHZ
Single phase 220V
80%
DW-HF-25 Series
DW-HF-25KW-A
DW-HF-25KW-B
25KVA
23A
20-80KHZ
3*380V
380V±10%
100%
DW-HF-35 Series
DW-HF-35KW-B
35KVA
51A
DW-HF-45 Series
DW-HF-45KW-B
45KVA
68A
DW-HF-60 Series
DW-HF-60KW-B
60KVA
105A
DW-HF-80 Series
DW-HF-80KW-B
80KVA
130A
DW-HF-90 Series
DW-HF-90KW-B
90KVA
160A
DW-HF-120 Series
DW-HF-120KW-B
120KVA
200A
U
.
H
.
F
.
DW-UHF-3.2KW
3.2KW
13A
1.1-2.0MHZ
Single phase220V
±10%
100%
DW-UHF-4.5KW
4.5KW
20A
DW-UHF-045T
4.5KW
20A
DW-UHF-045L
4.5KW
20A
DW-UHF-6.0KW
6.0KW
28A
DW-UHF-06A
6.0KW
28A
DW-UHF-6KW-B
6.0KW
28A
DW-UHF-10KW
10KW
15A
100-500KHZ
3*380V
380V±10%
100%
DW-UHF-20KW
20KW
30A
50-250KHZ
DW-UHF-30KW
30KW
45A
50-200KHZ
DW-UHF-40KW
40KW
60A
50-200KHZ
DW-UHF-60KW
60KW
90A
50-150KHZ

 

Portable Post Weld Heating Treatment System With Induction 

Main Application:

l  Preheat: weld heat,coating, spraying, bending, fitting&unfitting heat

l  Post-weld heat treatment: tank, boile, pipeline, steel sheet or other metal jobs

l  InductionHeat: mold heating, shipboard, zinc bath, large& irregular metal parts

l  Pipeline material heat: pipeline oil, pipeline gas, pipeline water, pipeline petrochemical and other pipeline material

Main Features

* High speed: 70%

*  Low tolerance

*  Energy Saving

*  High efficiency

*  Accurate heating

*  Simple operation

*  Non-contact heating

*  Environmental protection

*  Hypothermia circumstance

* Air cooling is suitable for low-temperature environment

* Induction heating is more uniform than oil,gas,flame heating portable post weld heating treatment system

MYD-20KWMYD-10KW
Input voltage3*380V, 50/60Hz, 4 Wires
Input Current1~30A1~15A
Output Current0~300A0~200A
Output Power1~20KW1~10KW, Max 15KW, 150% duty cycle
Output Frequency5~30KHZ
ThermocoupleK type
Temperature systemBuild in induction machine
Heating TemperatureMax800℃Max500℃
Size700 x 330 x 410 mm650 x 310 x 410 mm
Weight32kg26 kg
Induction Heating coil
Length10~20 M
Diameter15 mm
Working temperature-30~45℃
Pipeline SizeOD: 50~500mm or equivalent

Induction Preheating Hot Rod Heading With IGBT Heating Units

Objective Heat a waspaloy rod to 1500ºF (815.5ºC) for hot heading application
Material Waspaloy rod 0.5” (12.7mm)OD, 1.5” (38.1mm) length, ceramic liner
Temperature 1500 ºF (815.5ºC)
Frequency 75 kHz
Equipment • DW-HF- 20 kW induction heating system, equipped with a remote workhead containing two 1.32μF capacitors for a total of .66μF
• An induction heating coil designed and developed specifically for this application.
Process A seven turn helical coil is used to heat the rod. The rod is placed inside the coil and power is applied for two seconds
providing enough heat to penetrate the inner core. An optical 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:
• Low pressure and minimal residual stress
• Better grain flow and microstructure
• Even distribution of heating
• Improved production rates with minimal defects

Preheating Hot Rod Heading

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 1.12” (28.4mm) dia, 1.5”(38.1mm) tall, stainless steel shaft 1.12” (28.4mm) dia and various length, black brazing flux and braze shims
Temperature 1500 ºF (815 ºC)
Frequency 277 kHz
Equipment • DW-UHF-10 kW induction heating system, equipped with a remote workhead containing two 1.0μF capacitors for a total of 0.5μF
• An induction heating coil designed and developed specifically for this application.
Process A three turn helical coil is used to braze the carbide to the shaft. The steel shaft is fluxed and the braze shim placed on top. The carbide tip is fluxed and placed on top of the shim, lining up the countersunk hole in the carbide. The hole is not fluxed because the flux outgases and causes the carbide to build up pressure and attempt to repel from the shaft. Power is applied for 85 seconds for the braze shim to flow and make a good joint.
DAWEI’s customer has a customer who is unhappy with the braze quality of their digger so our customer is looking for a better quality brazing process. DAWEI’s customer is very happy with the sample brazed diggers and the help he received from the Ameritherm lab in developing his brazing process.
Results/Benefits Induction heating provides:
• Rapid localized heating only where needed
• Creates clean, controllable joints
• Hands-free heating that involves no operator skill for manufacturing
• Even distribution of heating

brazing carbide to shaft

 

 

 

 

 

 

induction brazing carbide to shaft

 

 

 

 

 

 

 

brazing carbide to stainless steel shaft

High Frequency Induction Cap Sealing With IGBT heating units

Objective To heat an aluminum foil inside a plastic shampoo cap for sealing
Material 2.0” diameter, plastic flip top cap, with a 0.9” diameter aluminum foil seal
Temperature 250 – 300 ºF (120 – 150 °C)
Frequency 225 kHz
Equipment DW-UHF-7.5 kW, induction heating system, equipped with a remote heat station containing two 1.5 μF capacitors (total capacitance 0.75 μF).
An induction heating coil designed and developed specifically for this application.
Process A three-turn two-position helical coil is used to heat the aluminum foil in a tunnel style assembly. Product (containers)
passes easily under the induction coil. The assembly is located such that the entire perimeter of the aluminum foil is heated
uniformly. The container and cap is placed under the coil and 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:
• uses a simple, economical coil design
• increases throughput with a dual-position coil
• delivers quality, consistent seals
• offers a repeatable process, well-suited for automation

induction cap sealing

Induction Heating Aluminum Foil For Cap Sealing with IGBT inductive heater

Objective An induction heater is used to heat a polymer laminated aluminum foil in 0.5 to 2.0 seconds. The heat produced in the aluminum foil melts the polymer that bonds to the neck of a plastic container.
Material Aluminum foil, polyethylene, polypropylene, polyvinylchloride, polystyrene, polyethylene terephthalate, styrene acrylonitrile
Temperature 300 – 400 (ºF), 149 – 204 (ºC)
Frequency 50 to 200 kHz
Equipment DAWEI solid-state induction power supplies operating between 1 & 10 kW at frequencies of 50- 200 kHz. These units operate with remote sealing heads which allows the main power cabinet of the equipment to be located away from the immediate production area. Distances of up to 100 meters are possible. The microprocessor is used to control
and protect the system and ensures that the optimal operating 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 for this application. The first assembly includes backing
board/reseal, a wax layer, aluminum foil, and a heatseal film for supported systems (Figure 1). The second assembly includes a high temperature film, aluminum foil, and a heatseal film for unsupported systems (Figure 2). The procedure is to fit the foil membrane into the cap and to fit the cap to the container after the product is filled.
Results For the aluminum foil assembly as shown in Figure 1, heat induced in the metallic foil by the induction coil almost
instantaneously melts the polymer coating and the neck of the container forming a hermetic seal between the heat seal film
and the rim of the container. The heat also melts the wax between the aluminum foil and the back board. The wax is
absorbed into the back board. This results in an air tight bond between the aluminum foil/membrane and the rim of the
container, the back board is released and remains in the cap.

Process (cont’d) In the case of unsupported membranes in Figure 2, one side of the aluminum foil is coated with a heat sealable polymer film and this face that will be in contact with and sealed to the container. The other side of the foil that will be in contact with the cap has a higher melting-point film that prevents adhesion of the aluminum to the cap allowing the end user to unscrew the cap. Unsupported membranes are typically used where the end user pierces the tamper evident membrane prior to dispensing the product. The aluminum foil acts as a vapor barrier preserving the freshness of the product and prevents it from drying.

induction heating aluminum foil cap sealing