RT2-140-10type wholly fibers Trolley furnace

 First, use

RT2- 140 - 10 type wholly fibers Trolley furnace is the national standard cycle-type energy resistance furnace, ultra-energy structure composite fiber insulation, ultra-lightweight high strength refractory material. Energy saving 20% ~ 40 % , the trolley uses labyrinth seal, integrated rail, easy installation, simple operation, mainly used for metal parts annealing, aging and low temperature treatment of various mechanical parts.

Second, the main technical parameters

1,    Power supply voltage: 380V

2,    Power frequency: 50HZ

3,    Number of phases: 3 phases

4,    Control voltage: 2 2 0V

5,    Rated power: 140 KW

6,    Number of temperature control zones: Zone 1

7,    Heating element connection: Y

8,    Rated temperature: 1000 °C

9,    Furnace size: 20 00mm × 10 00mm × 10 00mm

10.   Furnace temperature uniformity: ±1 5 °C

11,   Instrument temperature control accuracy: ± 1 ° C

12.   Furnace surface temperature: ≤45°C

13,    Heating element: 0Cr25Al5

14,    Circulating fan: 3kw water cooling fan

Third, the equipment structure

The structure of the RT2 series all-fiber metal annealing furnace is characterized in that the furnace consists of a fixed heating chamber and a movable bottom and an electric control system on the bench. The furnace body part is composed of a furnace body, a furnace lining, a heating element, a furnace door and a furnace door lifting mechanism. The bottom of the activity is composed of trolleys and trolley traction mechanisms.

1, the furnace body

The furnace body is welded by steel and steel plates, and the furnace shell panel is made of 10 mm thick steel plate. An electric heating element is arranged outside the furnace shell to take out the rod seat and the thermocouple seat. A safety shield is provided on the outside of the rod to prevent the ash layer and protect the personal safety of the person.

The welded structure of the steel structure is even and flat, and the appearance is straight, smooth, and there is no unevenness.

All steel sections and steel plates are mechanically rust-removed, and the primer is sprayed twice according to the relevant standards, and the top coat is applied twice.

Paint color: The top coat of the furnace is silver paint, and the other finishes are green. Or customize the color for the user.

2, furnace lining

The choice of lining refractory insulation material requirements meets the maximum heating temperature of the equipment, and its insulation performance mainly considers its density and construction method.

Ø lining structure

The composite lining structure is adopted: the folding block made of high-quality standard aluminum silicate refractory fiber blanket is fixed on the steel plate of the furnace body and the steel plate of the furnace door with anchors, and the surface of the lining is flattened with a high temperature acupuncture blanket.

Ø lining thickness

High quality standard aluminum silicate refractory fiber folding block lining thickness: 320mm. The compression capacity is ≥220Kg/m3. Anchor material: 321 heat-resistant stainless steel.

Ø standard aluminum silicate refractory fiber module installation method

First, heat-resistant steel anchors are welded on the shell steel plate, the anchor distance is 320mm, and then the compressed and bundled high-quality standard refractory fiber module is fixed on the heat-resistant steel anchor with a special tool.

High quality standard aluminum silicate refractory fiber has the following advantages:

1. Light weight (about 1/12 of refractory brick)

2, the thermal conductivity is extremely low

3, excellent heat insulation, fire prevention, sound absorption

4, warm up fast

5, low heat fusion

6, good insulation performance

7, good thermal shock resistance

8, excellent tensile strength

9. Excellent thermal stability and thermal shock resistance

10. Long service life, remarkable energy saving and convenient maintenance.

3, heating elements

The selection of heating elements is an important part of the whole heat treatment equipment. our company use the  cold drawn alloy resistance furnace inner walls laid with good uniformity, high oxidation resistance, the maximum temperature up 1 0 0 0 ℃, this design of the heating element according to technical parameters of a high temperature furnace technology selection parameters To ensure the service life of the resistance band.

4, furnace door and furnace door lifting device

(1) furnace door structure

The furnace door refractory insulation material adopts a full-fiber structure and is fixed on the furnace door steel plate with heat-resistant steel anchors. The surrounding area is surrounded by steel plates. During the production, the door fiber protrudes from the door frame to cover ~ 20 mm, so that the furnace door can be in close contact with the furnace body panel after the door is in place to improve the sealing performance.

(2) furnace door lift

The furnace door lifting mechanism is composed of a lifting chain, a lifting sprocket, a sheave, a bearing and the like. The furnace door lifting gantry is provided with groove-shaped guide rails on both sides. the furnace door moves up and down along the island rail. Furnace door lifting speed: 8m/min.

5, trolley and trolley transmission

The trolley consists of a frame, a refractory masonry and a running mechanism .

6, hot air circulation device

The hot air circulation device is composed of a hot air circulation fan and an air guiding cylinder .

1. hot air circulation fan

Fan with water cooling fan, the fan is fixed above the top of the furnace, the blower fan is a unitary, stable operation, low noise, low failure rate, and long service life. The fan is precision cast and can be installed under the fan after dynamic balancing and static balance correction. This results in longer life and less noise.

2. air deflector

The air deflector is made of 3 mm thick 304 stainless steel plate, formed by a coiling machine, and then welded with stainless steel welding rod, which will be placed in the furnace for use. Ribs are welded on the outside of the air deflector to prevent deformation during use and prolong service life.

The principle is: when the fan is running, a turbine air vane and a wind guide cylinder form a hot air circulation air convection system in the furnace, thereby ensuring uniform temperature in each corner of the furnace, and the fan power supply and the furnace lid opening and closing form a chain function. When the furnace cover is opened, the heating power supply and the fan power supply are cut off, and the fan stops working.

7 , electrical control system

The control system includes temperature control and drag control, which is the main part  of the trolley-type resistance furnace operation. It controls the information collection, comparison, calculation and display, and is controlled by temperature control instruments and other electrical components to make the trolley-type resistance furnace run safer and more reliable.

(1) Temperature control:

The temperature control main circuit consists of high-intelligence, high-precision, program temperature control instrument with PID adjustment, temperature sensor and solid state relay module to form a closed-loop control of the temperature heating system.

The device is controlled by a zone, and the heating zone is controlled by a thermocouple and a temperature control instrumentand a solid state relay (SCR) module. The thermocouple is mounted on the top of the furnace.

The intelligent instrument with PID adjustment system can control the temperature of the furnace by step heating and heat preservation according to the process requirements. The temperature rise and heat preservation are carried out according to the process temperature curve, and the power supply heating power is determined according to the process requirements, thereby avoiding the disadvantages of excessive temperature rise and large temperature fluctuation due to thermal inertia during heat preservation, and accurately controlling the temperature inside the furnace.

The temperature control system has advanced intelligent PID control algorithm, high temperature control precision, perfect self-tuning and adaptive function.

(2) Drag control device

The trolley is driven in and out, and the door lift is driven by a motor. The drag control is controlled by electrical components such as buttons, AC contactors, and thermal relays.

(3) Interlock protection and grounding

 furnace door is raised to the highest position to allow the entry and exit of the trolley.

 furnace door is interlocked with the heater, that is, when the furnace door is raised ,the  heated will be de-energized, the furnace door is lowered to the lowest point, and the heater can be connected.

 Control cabinet and furnace shell are reliably grounded

( 4 ) Control cabinet

The temperature control cabinet adopts a standard cabinet, and the cabinet has an illumination tube. When the cabinet door is opened, the illumination lamp is energized for illumination. Each phase electric heating element has a corresponding voltmeter and ammeter, which can visually display the on/off indication of electric heating. A control cabinet is used for the temperature control device and the drag control device. Both the control cabinet and the furnace body have a safety grounding device.

Wiring locations and electrical components are clearly identified and numbered.

Fourth, use and maintenance

Firstly,  should check whether the equipment is installed correctly according to the drawings, whether it meets the process requirements, check whether the temperature control instruments are running normally, check whether the grounding device is connected properly, and the insulation resistance should be ≥ 0.5M Ω. The equipment should be ovend before use. For the furnace that has just built the lining, it should be naturally dried in air at a temperature of not less than 10 °C ~ 15 °C for 2 to 3 days and nights, and then ovend according to the following system:

Note:If the lining refractory fiber is damaged, it can be repaired with a needled fiber blanket and a high temperature binder.

If there is slight damage to the load-bearing part of the trolley, it can be repaired with mud. If the damage is serious, the new brick can be replaced.

The formula of refractory mud for bricklaying is: clinker powder (high aluminum powder) 70%, clay 30%, both particles are not more than 180 mesh, and the repaired lining can be carried out with reference to the oven process listed in the above table.