Induction heaters

Treat new and used bearings with the same care. Use an induction heater for installation. 

Figure 5. Direct heat balance element plots for Crosslinker Preparation. Calculated induction heater input and cooling coil heat removal rates.

To exploit this observation, a cylindrical bar of material is passed slowly through an induction heater and a narrow molten zone is moved along its length. This causes the impurities to segregate at one end of the bar and super-pure material at the other. In general, the impurities move in the same direction as the molten zone moves if the impurities lower the melting point of the material (see p. 212). 

Figure 6.3. Levitation of a molten metal in a radio-frequency field. The coil consists of water-cooled copper tubes. The counter winding above the sample stabilizes levitation. The same coils (and possibly additional ones) act as the induction heater. This technique has been applied to container-less melting and zone refining of metals and for drop calorimetry of liquid metals. It can be also used to decarburize and degas in ultrahigh vacuum mono-crystalline spheres of highly refractory metals (adapted from Brandt (1989)). The arrows indicate the instantaneous current flow directions in the inductors.

Shinn (1982) developed a mechanically agitated slurry reactor with induction heaters for coal liquefaction. While the induction heaters required large power input, they allowed the slurry to heat up to 400-450°C in few minutes, thus cutting down the heat-up period. In the use of such reactors, the effects of induction heating on the metal degradation and failure need to be carefully considered. Except for the induction heating system, the rest of the reactor was a conventional slurry reactor. The concept of induction heating is more practical for smaller-size reactors. 

Slurry reactors are often used for intrinsic kinetic measurements. In order to alleviate the effects and complications of the initial heat-up period, as well as the induction period, on the kinetic measurements, novel designs have been introduced. Cup-and-cap reactors, falling-basket reactors, rapid-injection reactors, reactors with induction heaters, and microreactors are five such novel designs. Each of these reactors has been found to be successful the first three, however, consider both induction and heat-up periods. The last two reactors alleviate the complications due to the heat-up period only. All of these... 

A method of purifying a bar of metal by passing it through an induction heater this causes impurties to move along a melted portion. 

Zone refining a method of purifying metals. An ingot of metal passes through an induction heater, and in this way impurities are accumulated in the melted portion of the ingot... 

TV, video display units, induction heaters Induction heaters, electronic surveillance Radio AM, FM, and TV broadcasting Mobile telephony GSM (European standard)... 

Zone refining is often used when extremely pure metals are desired for such applications as solar cells and semiconductors (Section 13-17). An induction heater surrounds a bar of the impure solid and passes slowly from one end to the other (Figure 22-4). As it passes, it melts portions of the bar, which slowly recrystallize as the heating element moves away. The impurity does not fit into the crystal as easily as the element of interest, so most of it is carried along in the molten portion until it reaches the end. Repeated passes of the heating element produce a bar of high purity. 

Radiofrequency Supply. A commercially available (20) 12 kw. (nominal) induction heater, oscillating at 4 MHz., was the power source for the experiment. The load coil, shown in Figure 1, consisted of five turns of 1/4-inch o.d., water-cooled, copper tubing wound tightly around... 

Figure 20.2 Technological scheme for recovery of rigid PU foam wastes by glycolysis process (variant) 1 Mills for PU scrap 2 Storage of ground rigid PU foam 3 Screw for powdered materials 4 Glycolysis and alkoxylation reactor 5 Electrical induction heaters 6 Filter press 7 Storage tank for the recovered polyol 8 Gear or screw (or...

ITie melting furnace consists of a ceramic melting crucible heated to a temperature of around 1150°C by five induction heaters. The molten glass is allowed to build up in the furnace for a period of 8 h, and then a glass plug in the bottom of the furnace is melted through the use of two additional induction heaters and the glass is poured into the stainless... 

The heating rate was controlled by adjusting the output of the induction heater. The fast and slow heating rates were approximately 140 and 14°C/min, respectively. A 500-W band heater was used to mimic the conventional heating process. The conventional heating rate using the band heater was approximately 5°C/min. 

Heating. The rebars are then heated using an induction heater. This does not contaminate the already clean bar surface and allows a constant coil voltage combined with a constant bar speed to produce very uniform surface temperatures. 

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