Gas Fired Metal Parts Industrial Car Bottom Furnace Heat Treatment 1160×1260×1200mm

Gas Fired Metal Parts Industrial Car Bottom Furnace

Heat Treatment 1160×1260×1200mm

1. Application

The gas fired bogie hearth furnace is mainly used for heat

treatment of metal parts.

2.Structural Introduction

2.1 furnace body

The bogie hearth furnace body steel structure is made from 8# -12# channel

steel and 4-14mm 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 main material of the furnace lining is made of high temperature refractory

fiber folding block at the long-term service temperature of 1000℃. This refractory

lining structure has the advantages of low heat conductivity, strong anti-shock capacity,

and anti-erosion. Aluminum silicate fiber compression block with thickness of 300mm

is designed as the high temperature refractory layer.

2.3 bogie

The bogie is comprised of heat preservation material, bogie frame and moving

mechanism. The refractory layer is divided into 3 sub-layers, i.e., 1st top high-alumina

brick layer, and 2nd and 3rd layer with both light clay bricks.

The bogie framework is made of 12# channel steel. The bogie has enough rigidity

to ensure no deformation under full load operation. The gap between the two sides

of the furnace bogie and the frame of the fire-resistant trolley should be fixed.

The bogie surface plate is made of 6 mm high quality steel plate. The function is to

disperse the bogie load (make the load distributed evenly) and enhance the frame

rigidity.

The bogie is self moving type. There are 4 wheels with the diameter of 240mm. Two

wheels are driving wheels, and the other two are driven wheels.

The bogie traction mechanism: the trolley traveling mechanism is driven by AC motor

reducer, and the driving mode is reducer sprocket structure. The trolley goes in and

out of the furnace through the reducer sprocket in the transmission device and the

traveling wheel under the trolley to drive the trolley traveling sprocket to mesh and

drive the trolley traveling, which is stable and reliable.

2.4 furnace door

The bogie hearth furnace supplier door is comprised of all-fiber lining and steel

structure shell. The door is built with silicate aluminum compressed fiber blocks

same as that for the furnace body. The shell is a welding structure from sectional

steel and steel plates. The furnace door has the feature of simple, practical, reliable

and convenient maintenance.

Driving mode of furnace door: electric hoist is used to move up and down vertically.

furnace door lifting is completed by a set of pulley block and electric hoist. The pulley

block is installed on the upper gantry of the furnace door. The furnace door is connected

with the steel wire rope through the ring chain, and the electric hoist is installed on the

gantry of the furnace door.

The structural features of furnace door: the main material of furnace door is welded with

steel plate and section steel, and the intersection is reinforced with hexagon reinforcing

plate, which can not only ensure the overall rigidity and strength of furnace door, but

also make the furnace door light and reduce the weight of furnace door. The fiber lining

adopts the hanging riveting method, which can effectively ensure the firmness of the

fiber due to the frequent opening and closing of the furnace door, and increase the

service life of the furnace door.

The upper and lower safety mechanisms are set on the furnace door and interlocked

with the trolley. In order to prevent the trolley from running out of control and hitting

the rear wall of the furnace, a mechanical elastic limiting device is installed on

the trolley

2.5 burning system

The burning system is comprised of Krom high speed burners, proportional

combustion control system, gas valve, solenoid valve, burner control box, etc.

The burner has the functions of automatic ignition, flame detection, and flame out

alarm. The burner controller receives the control signal of the temperature controller

and controls the large/small fire status of the burner based on the heat load

requirement so that adjustment of the temperature is realized.

A) The burner has adjustment function and the adjustment rate is 1:10 and the air

efficient is 1-5. The burner could meet the temperature uniformity of the heat treatment

process and effectively control the air-gas ratio so that the fuel consumption is reduced.

B) When the furnace is working, the burning system could automatically cut off the

electrical gas valve and general safety valve in the case of power failure detected by

the alarm system. When the power supply is resumed, the worker needs to open

the safety valve and restart the ignition program after purging function is confirmed.

The burner is set with a proportional control unit which enables alternative burning

of large and small fire, fire out alarm, and re-ignition. The burner control box has both

manual and self-run modes available. The worker could operate in front of the furnace

or in the control cabinet.

C) The pipe before the burner is equipped with solenoid valve, and manual gas

adjustment valve. The valve system could realize an ideal gas/air supply ratio so

that the air excess efficient is lower than 1.1.

2.5.1 air system

The air piping system is comprised of high pressure centrifugal fan, automatic regulation

valve, pressure gauge and pipes. The air volume is to match the gas volume, and the

air excess rate is lower than 1.20.

2.5.2 gas supply system

The general gas supply pipe is equipped with a pressure regulation device

(equipped with a filter), a low pressure switch and a pressure gauge. For the sake

of safety there is one fast cut-off valve on the general gas pipe.

2.5.3 discharge system

The heat treatment furnace trolley takes direct fume discharge method. The fume is

directly vented out through the flue pipe to the atmosphere. The fume conducts heat

exchange with the heat exchange before emission to the atmosphere.

2.5.4 Furnace pressure control system

The pressure on the working table in the furnace is kept at (+15 Pa), which is very

beneficial to the uniformity of temperature and the thermal efficiency of the furnace.

When the pressure in the furnace is too high, the hot air in the furnace will escape from

the furnace mouth and other unsealed places, resulting in the heat loss caused by the

escape of the flue gas; because the high temperature flue gas in the furnace escapes to

the outside of the furnace, it will affect the door, the side seal and burner of the furnace

directly, which is related to the overall service life of the furnace; when the pressure in the

furnace is too low, a large number of cold air outside the furnace will be absorbed into the

furnace, as well. The heat loss of off-furnace flue gas is increased. The low pressure of the

furnace causes the diffusion of cold air outside the furnace into the furnace, and secondary

combustion is formed due to the entry of oxygen-containing cold air, which has adverse

effects on the uniformity of furnace temperature, oxidation of workpiece and thermal

efficiency of the furnace. Therefore, effective technical measures must be taken to control the

furnace pressure with full automatic control. Our method is to control the furnace pressure

effectively by using a system consisting of pressure taking device, pressure transmitter,

intelligent instrument and so on. The furnace pressure is controlled in the optimum state

(the surface of the trolley is in a slightly positive pressure). At this time, the exhaust gas is

in a dynamic equilibrium state, which can not only ensure that the furnace gas does not

overflow, but also ensure that the cold air outside the furnace is not sucked into the furnace,

so as to save energy and maximize the efficiency of the furnace.

2.5.5 Heat exchange and flue system

A flue is set at the back of the furnace, and it is carried out with the heat exchanger

(according to the national standard GB3486-83). The flue leads to the outside of the

factory building. The cold air is exchanged with the heat exchanger to preheat the

combustion-supporting air before entering the burner, so as to improve the heat efficiency

of the furnace.

Heat exchangers and flue gas exhaust pipes are insulated by internal insulation (using

fiber castables) to ensure the service life of heat exchangers and flues.

2.5.6 fault detection and alarm system

The tempering bogie hearth furnace has a complete fault detection, alarm, diagnosis,

and safety protection system. On the control cabinet there is an alarm lamp.

2.6 control system

control system has the following parts: Ⅰ. Burning control system; Ⅱ. Electrical power

control system; Ⅲ.temperature control system .

Measures taken for burning control system:

K type thermal couple gets mV signal and sends it to temperature PID controller

(SHIMADEN brand). The temperature controller calculates the signal and outputs

4-20mADC control signal to the electrical actuator. The actuator further sends a signal

to the burner controller after calculation.

The burner controller is mainly responsible for ignition and flame detection. When the

terminal receives the ignition signal, the burner controller carries out flame simulation

and self testing stage. If during this simulation and self-test stage the burner couldn’t

detect the flame signal. The burner controller would open the gas solenoid valve and

convert the voltage 220VAC to 5KV for ignition (ignition time about 3S). If the burner

detects the flame signal in the safe time period (about 8S), the yellow indication light of

the burner would be on (ignition successful). If the burner couldn’t detect the flame signal,

the red light would be on (ignition failed). The burner controller is locked and the gas solenoid

valve is cut off.

B) electrical power control system: The electrical power control system mainly controls

ON/OFF of the fan, and IN/OUT of the bogie.

C) temperature control and record system

The system has the functions of temperature setup, control and digital display. And also

there is an audible and visual alarm at over-temperature situations.

Temperature control zone arrangement

A:temperature control system

The furnace is equipped with 1 thermal couple and an intelligent temperature controller.

The furnace is controlled by 1 zone.

B: instrument temperature control

The temperature controller allows setup of heating time, holding time, and cooling time.

It has self-tuning and self-adjustment function, and displays SV and PV.

3.Main Technical Parameters

 Wuxi Wondery Industry Equipment Co., Ltd, established in year 2013, is a professional supplier engaged in the sale and after sale service of Melting Furnaces, Heat Treatment Furnaces, Hot Dip Galvanizing Furnaces. Our factory is dedicated to strict quality control and thoughtful customer service, our experienced staff members are available to discuss your requirements and ensure customer satisfaction. In recent years, our company has introduced a series of advanced products including aluminum melting furnace, bogie hearth furnace, mesh belt furnace, induction melting furnace, hot dip galvanzing furnaces, etc. In addition, we have obtained C E certificates. Selling well in all cities and provinces around China, our products are also exported to clients in such countries and regions as U S A, Australia, Russia, Turkey, Poland, Italy, Romania, South Korea, Kazakhstan, India, Jordan, Thailand, Vietnam, Brazil, Mexico, Argentina, Venezuela, Colombia. Whether selecting a current product from our catalog or seeking after sales service for your application, you can talk to our customer service center about your sourcing requirements. Adhering to the business principle of mutual benefits, we have had a good reputation among our customers because of our perfect services, quality products and competitive prices. We warmly welcome all dear customers to cooperate with us for common success.