Characteristics and Uses of Roller Hearth Furnace
The roller bottom furnace is provided with a plurality of lateral rotating rollers at the bottom of the straight through the furnace to drive the charge on the roller bar along the table. The charge is continuously moved during the heating process, and there is no fixed contact point with the roller table, so the heating is uniform, no bruise, deformation is small. As the roller is always in the furnace, the heat consumption is relatively small, the furnace thermal efficiency is high.
This roller-bottom furnace is not only suitable for handling large plate and bar, and 90 ~ 100mm bearing ring can also be placed directly on the roller, the diameter of less than 90mm and more than 40mm rolling plate can be loaded plate for heat treatment. This kind of stove has good adaptability to heat treatment parts, the main drawback is that the stick requires a higher cost.
Both ends of the roller through the furnace out of the furnace outside the support on the bearing, the motor through the drive mechanism, so that the roller rotation.
Furnace temperature below 950 ℃, can be used with water-cooled shaft head and without water-cooled shaft of the cylindrical roller; when the furnace temperature at 1000 ~ 1100 ℃, often use water-cooled shaft of the empty roll. As the cooling water to take away a lot of heat, and some relative to the 1000 ~ 1150 ℃ roller-type furnace to steel production of anhydrous cold furnace roll, the structure is the furnace roller roll at both ends were welded on the drive shaft and passive shaft, Two-axis center marked with 30mm hole, increase the cooling area of the shaft, reduce the operating temperature of the shaft, the use of high-temperature refractory fiber as the axial filling material for insulation, while the furnace roller roll ends were welded on the drive shaft and passive shaft, The center of the two shafts are marked with 30mm holes to increase the heat dissipation area of the shaft, reduce the working temperature of the shaft, use high temperature refractory fiber as the axial filling material for adiabatic, and change the whole type of the roller roll to the combination type. High temperature roller commonly used materials are made by centrifugal casting.
The main parameters of the roller are roller diameter and wall thickness. It is related to roller roll distance, heating condition, working condition, furnace roll speed and load. The design roller mainly calculates the bending stress of the roller. The roller has two basic requirements, Requires the roller carrying capacity, long life, but also hope that the furnace roll light weight, low cost. The load of the roller is in addition to the load of the charge, but also with the quality of the roller itself, so the roller diameter should be selected reasonably.
The roller spacing should ensure that the load on the roller can run smoothly. The center of gravity of the charge should always be within the support roll, generally require two rollers to support the charge. The spacing of the rollers should also be matched with the drive chain and should take a multiple of the chain pitch.
Roller bottom furnace is also useful non-metallic roller, used in the load lighter, high temperature conditions, non-metallic roller materials are trioxide and silicon carbide.