摘要:
A method is disclosed for preheating a metal strip in at least one direct fired preheating section of a furnace for limiting the oxidation of the metal strip. The method includes installing burners in the preheating section along its length for establishing a plurality of preheating sub-zones of unit length corresponding to one burner. The air and fuel settings for each burner are adjusted in accordance with a desired heat demand. Subsequent steps include operating a variable number of downstream burners at full power to establish a preheating zone of variable length to produce the desired heat demand, and extinguishing a second variable number of upstream burners to establish a corresponding variable recovery zone.
摘要:
A process is disclosed for the continuous thermochemical treatment of metal strip. It is useful with steel strip, of the oxidation-reduction type, in which the strip moves through a furnace in a protective atmosphere. The strip passes through at least one partial or total isolation device positioned within one or more sections of the furnace. The strip is heated in this isolation device in atmospheres having a dew point tailored to each strip according to the specific composition of the steel so that the atmosphere is oxidizing in the case of certain addition elements, but remains reducing in the case of iron.
摘要:
A process for the protective or decorative coating of a continuously moving metal sheet, in which the sheet, after having received its coating, is heated by electromagnetic induction in a tunnel oven in order to evaporate the solvents and to cure the coating. The solvents are continuously extracted from the chamber of the oven, wherein a gas at a temperature greater than the dew point of the solvents is injected into the oven and which is gastight and thermally insulated in order to keep the hot internal walls above this dew point.
摘要:
The measuring device comprises two flat-wall heat exchangers (3a, 3b), one to each side of a flat plate (1), two samples (2a, 2b) of similar thickness (E) of the material being tested, placed between the outer surface of the heat exchanger (3a, 3b) and one surface of the central plate (1), a device for positioning and holding the heat exchangers (3a, 3b) and at least two temperature sensors, one of which (T2) consisting of a thermocouple is incorporated in the central plate (1), the other (T1) also consisting of a thermocouple, being incorporated in the outer wall of the plate of one of the heat exchangers (3a). Application in the injection of plastics.
摘要:
A device for microwave treatment of materials includes a mold (1) used to hold the material (3) to be treated and a microwave generator which is used to apply to the mold (1) the microwave energy necessary for treatment of the material. The mold includes at least two dielectric materials (4,5,6,7) surrounding the material (3) to be treated. The dielectric materials have dielectric permittivities which differ so that the attenuation of one elementary segment of length l located between the points of side z(n-1) and zn of the longitudinal dimension of the material (3) to be treated which includes at least one section broken up into segments of length l, is controlled by the relationship: ##EQU1## in which: .alpha. is the attenuation in the elementary segment in question,.alpha.o is the initial attenuation in the body of the section which includes the elementary segment in question,Po is the microwave power applied to the section, P(n-1) is the microwave power transmitted in the plane of side z(n-1).