1. |
With fuel-based systems, heat is generated by the combustion of solid, liquid, or gaseous fuel, and transferred either directly or indirectly to the material. The combustion gases can be either in contact with the material (direct heating), or be confined and thus be separated from the material (indirect heating). |
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True |
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False |
2. |
Electric-based process heating systems (sometimes called electrotechnologies) use electric currents or electromagnetic fields to heat materials. |
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True |
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False |
3. |
Direct heating methods generate heat within the work piece by either (1) passing an electrical current through the material, (2) inducing an electrical current (eddy current) into the material, or (3) exciting atoms and/or molecules within the material with electromagnetic radiation. |
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True |
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False |
4. |
Agglomeration and sintering refers to the heating of a mass of fine particles below the melting point to form larger particles or solid parts. |
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True |
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False |
5. |
______________________ is the controlled heating of a substance to promote or control a chemical reaction in the manufacture of plastics, curing is the cross-linking reaction of a polymer. |
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Curing |
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Calcining |
6. |
Fluid heating is used to increase the temperature of a liquid or gas, including the complete or partial vaporization of the fluid, and is performed for a wide range of purposes in many industries, including chemicals, food processing, and petroleum refining. |
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True |
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False |
7. |
__________________________ is the controlled heating and cooling of a material to achieve certain mechanical properties, such as hardness, strength, flexibility, and the reduction of residual stresses. |
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Drying |
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Heat treating |
8. |
_________________________ is the chemical reduction of a metal from its ore, typically by fusion. It separates impurities, thereby allowing their removal from the reduced metal. |
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Smelting |
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Calcining |
9. |
A furnace in which the heated materials are held in a refractory vessel for processes such as melting or calcining is termed as the ________________________________. |
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Burning Furnace |
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Crucible furnaces |
10. |
Dryers are used to protect the environment by burning combustible waste products in the petrochemical industry. |
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True |
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False |
11. |
Thermal fluid systems use oil or salt based heat transfer medium to carry heat from the generation source to the heated product, similar to the way steam is used in process heating applications. Thermal fluid systems have much lower vapor pressure-to-temperature characteristics, which means that thermal fluids can provide high-temperature service (up to 750˚F) without the high pressures that would be required with steam. |
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True |
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False |
12. |
In electric infrared processing, metals are heated by a directed, focused beam of electrons. It is used extensively in many high-volume applications for welding, especially in the automotive industry. |
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True |
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False |
13. |
A fuel-based process heating system and opportunities for improvement is represented in _____________________. |
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Figure 1 |
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Figure 2 |
14. |
Electric-based process heating systems are controllable, clean, and efficient. These systems use electric currents or electromagnetic fields to heat materials. |
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True |
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False |
15. |
The primary application of large arc furnaces is in processes for melting of metals, primarily iron and steel from scrap steel and iron as raw materials. |
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True |
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False |
16. |
Direct arc furnaces used for steelmaking are typically smaller than integrated basic oxygen furnaces. |
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True |
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False |
17. |
Direct arc furnaces are used in smelting processes to produce materials such as silicon alloys, ferromanganese, calcium carbide, and ferronickel. |
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True |
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False |
18. |
Induction arc furnaces are used for a variety of metal melting applications and perform the same processes as various types of fuel-based furnaces. |
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True |
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False |
19. |
Warm-up time is the time required to bring a process heating system up to operating temperature. |
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True |
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False |
20. |
Sensible heat is the amount of heat required to raise a unit weight of a substance under a specified temperature and pressure. |
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True |
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False |
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