Structural Introduction
The RT3-105-6 bogie hearth furnace is mainly comprised of
furnace body, lining, furnace door and door compression system,
bogie, heating element, circulation device and temperature control system.
2.1 furnace body
The car bottom furnace body steel structure is made from 10-12#
sectional steel and ≥3mm steel plates. The side pillar and back pillars
are made from sectional steel, and are reinforced with sectional steel
bracings. The external wall of the furnace is painted with 2 layers of primers,
and 2 layers of coating paint. The key part of the furnace is painted with heat
resistant paint.
2.2 lining
The high temperature bogie hearth furnace body is built with an all-fiber system.
The lining material used is quality aluminum fibers fixed by round steel parts.
The aluminum fibers are pre-compressed into blocks (compression gravity:
≥230Kg/m3 ) and then fixed to the furnace body by round stainless steel parts.
This refractory lining structure has the advantages of low heat conductivity,
strong anti-shock capacity, and anti-erosion. The lining has a total thickness
of 240mm. The silicate aluminum fiber resists a maximum temperature of 950℃.
2.3 furnace door and door up-down system
The Electrical Bogie Hearth Furnace door is comprised of all-fiber lining and
steel structure casing. The door frame is made of 10mm steel plate. The door
is built with silicate aluminum fiber blocks same as that for the furnace body.
The overall structure of the furnace maintains its shape while heated.
Driving method of door: The furnace door is electrically lifted upward and
downward by the hoist. And it is sealed by spring.
2.4 bogie
The bogie is comprised of bogie frame, wheels, refractory bricklaying body,
heat resistant bogie face plate, heating elements, and bogie driving mechanism.
bogie structure: the bogie frame is made from 14# beam and 10mm steel plates.
The bogie could work for a long time without deformation at full load.
wheel: The wheels are made from ZG55# steel casting. The transmission shaft
is made from 45# steel, and it is heat treated. The transmission bearing is of the
heavy type pillar bearing to bear the weight. There are a total of 2 pairs of wheels,
and each wheel is of diameter 240mm.
bricklaying body: The bogie is built with a combination of high alumina refractory
bricks, light refractory bricks, and heat preservation bricks. The bricklaying body
of the bogie has heating elements installation slot for easy installation of the heating
elements. The impacted parts and weight bearing area are bricked especially with
heavy type high aluminum refractory bricks. There is also free space left for the
refractory lining expansion when heated.
Sealing: The seal between furnace door and furnace body and bogie is more
important. The seal between furnace door and furnace body adopts spring
compression structure. The seal between bogie and furnace body is seal of
special-shaped brick and fiber cotton block.
2.5 heating element
heating element: The 0Cr25AL5 resistance spiral-shape alloy resistance strips
are mounted in 5 side walls, two side walls, back wall, furnace door and bogie
bottom. The resistance strips are produced through special molds, and are installed
in the furnace wall by porcelain nails. And there is a porcelain gasket between
the fiber wall and the resistance strips to avoid short-circuit. There are 1 heating
zone. All lead-out conductor bars are made of φ16 0Cr25AL5 material.
2.6 electrical control system
Temperature control: the furnace adopts intelligent temperature controller to
control the temperature which has self-tuning function to calculate the ideal PID
parameter and achieve a temperature stability. The temperature controller has
the functions of over-temperature alarm and thermal couple breakage protection.
The furnace has 1 temperature control zone for controlling the linkage between
the temperature and the motor movements. Each zone is set with an over-temperature
alarm. The heating loop adopts the double-direction SCR and trigger control. The
power is regulated in the time proportional regulation manner.
The control actuation system is a large-power triggering one complete with a
radiator and an air cooling system. There is also an air switch. The heating loop
is equipped with ammeter, voltmeter, heating element on-off indicator, power-on
interlock protection, and safe earthing measures.
Movement control: The control system mainly controls the door up-down movement,
door compression, and door in-out movement. Also the movements are necessarily
linked to ensure the operation safety.
2.7 Hot air circulating system:
It is mainly comprised of two centrifugal fans and an air guide plate in the furnace.
The heat emitted by the heating element is evenly blown to the effective working
area by the circulating fan through the wind guide plate. The air guide plate is made
of 1Cr18Ni9, and the fan and shaft are made of 1Cr18Ni9Ti. In order to ensure the
normal use of bearings, the cooling method is air cooling.
Guide device: it mainly circulates the air generated by the circulating fan in the furnace
along the direction of the guide plate effectively in the furnace, so as to make the air in
the furnace produce rapid convection, so as to achieve the goal of temperature
uniformity. The materials of wind guide plate and framework are all made of 304
stainless steel plate. The air guide plate and the framework are connected in a
movable way to ensure the free expansion of the air guide plate under high temperature,
and it is convenient for repair and maintenance.
