Electrical Bogie Hearth Furnace Heat Treatment 1500×1000×1000mm Structural Steel

1500×1000×1000mm Electrical Bogie Hearth Furnace

1. Application

The RT3-110-11 electric bogie hearth furnace is mainly used

for annealing, quenching and normalizing of steel parts, casting

parts and stainless steel parts, etc.

2. Structural Introduction

The RT3-110-11 bogie hearth furnace is mainly comprised of furnace

shell, lining, furnace door, furnace door lifting mechanism and door

compression mechanism, bogie, bogie traction mechanism, sealing

between furnace body and bogie, heating element and fixed device,

and temperature control system.

2.1 furnace shell

The electric resistance car bottom furnace body steel structure is made

from 8-10# 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 gas car bottom 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 325mm. The silicate aluminum fiber resists a maximum temperature of

1260℃. The fiber fasteners are made of stainless steel.

2.3 furnace door and door up-down system

The fast quenching heat treatment furnace door is comprised of all-fiber lining

and steel structure casing. The furnace shell is made of 12mm steel plate for

the door frame. 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 self-weight of the furnace door.

2.4 bogie

The bogie is comprised of bogie frame, wheels, refractory bricklaying body,

heat resistant bogie hearth plate, heating elements, and bogie driving mechanism.

bogie structure: the bogie frame is made from 12mm steel plates and 12# steel

beam. 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. The bogie is motorized. And the driving motor

is equipped with a braking speed reduction device to relieve the inertia at the start-up

and stop movement. There are 2 limit switches to avoid over-travel of the bogie.

bricklaying body: The bogie is built with a heavy combination of high alumina

refractory bricks, light refractory bricks, and heat preservation bricks. 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.

bogie hearth plate: 30mm thick ZG35Cr24Ni7SiN heat resistant steel casting

part with max working temperature≤1200℃. It can prevent scales from falling into

the heating elements slot which would form a short circuit.

bogie moving mechanism: The bogie has a self-moving method. The reducing

gear drives the bogie wheel to move. The bogie movement is smooth and stable.

Sealing among furnace door, furnace body and bogie: Sealing between the

furnace door and the furnace body is through self-weight pressure tightening

mechanism. The sealing between the bogie and the furnace body is through

soft special shape bricks and fiber cotton block.

2.5 heating element

heating element: The 0Cr27AL7Mo2 resistance spiral-shape alloy resistance

strips are mounted in 2 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 0Cr27AL7Mo2 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.

A. According to the process requirements, the temperature rise program is set in

the intelligent instrument and distributed to each temperature zone for control.

Call and edit the corresponding process, send signals to the lower level, and

collect the temperature of each zone from the upper instrument.

B. When the main power supply is turned on for operation, the equipment will normally

control the electric furnace according to the program process set in the intelligent

instrument.

(2) Power control: it adopts high-power trigger system, equipped with radiator and

a full set of air cooling system. Each group of electric heating elements shall be

equipped with ammeter, voltmeter and on-off indication of electric heating elements,

with power on interlocking protection and safe grounding measures to ensure safe use.

The lifting of the furnace door and movement of bogie are all completed in the control

cabinet. There is reliable electrical interlocking between each action and power on

interlocking protection with the electric heating system.

3.Main Technical Parameters