- Model NO.: ND-HF-1250
- Place Style: Horizontal
- Type: Industrial Furnace
- Fuel: Gas
- Transport Package: Steel Sheet
- Origin: China
- Certification: CE, ISO
- Range of Applications: Industrial
- Usage: Steel Molding
- Trademark: Nianda
- Specification: CE
- HS Code: 8514901000
This electrical resistance furnace is designed for annealing aluminium coil, it also can be supplied for aging, tempering treatment of other metal parts under oxidization atmosphere. Working process like heating, temperature control and mechanical movement is automatically controlled by industrial computer and auxiliaries instruments. Mechanical movement are interlocked with each other. Inner atmosphere are circulated by fan, which can ensure temperature uniformity within ±5ºC.
2,Scope supply of the equipment
|2||Hot air circulating fan||5 Sets|
|3||Heating Elements||1 set (60 pcs )|
|4||Air duct and guide-flow hood||5 sets (each zone designed with 1 set)|
|5||Furnace door and its lifting device||1 Set|
|6||Door Clasping and sealing device||1 Set|
|8||Sealing Unit||1 Set|
|9||Coil supporting bracket||1 Set|
|10||Electrical control system||1 Set|
3. equipment configuration
This car bottom electrical resistance furnace consists of furnace case, furnace lining, furnace door and its lifting device, car device, heating elements, and electrical control system.
3. 1 Furnace Steel Structure
Furnace body: It adopts formed steel and high quality steel plate and welded together. Steel frameworks are designed for supporting parts. Furnace shell framework includes roof steel structure, side steel structure, and rear wall steel structure and furnace port steel plate.
Furnace roof steel structure is made of [12# formed steel and steel plate (thickness: Q235δ5mm) and welded together. Seam between formed steels is continuously welded and seam between formed steel and steel plate adopts rivet-spot-welding method.
Side steel structure is made of angel steel and steel plate (thickness: Q235δ5mm) and welded together. The welding method is same with furnace roof.
Rear furnace steel structure adopts 18# channel steel and δ5mm steel plate and welded together. To improving heat resistance, furnace port adopts Q235 steel plate and rivet-spot-welded with formed steel structure.
Furnace steel structures are partially fabricated at the Seller's shop. So it is easy to transportation and installation. All pieces are assembled at the Buyer's factory. Such kind of structure has high rigid, novelty appearance, reliable and free of deformation. Etc. Overall outer surface is coated with three layers of anti-rust paint. Inner layer is performed with anti-rust paint. Outer layer is sprayed with high-temperature silver color paint.
3.2 Furnace Lining
To ensure temperature is fast heated up, save energy, and control sensitively, it adopts full fiber structure.
The alumina-silicate fiber (thickness:200mm) are fixed with furnace wall by special anchoring parts. One layer of δ2 304 steel sheet are coated with fiber, thus to enhance its anti-erosion abilities and prolong its service life. The riveting parts adopt professional technology which is easily installing and free of short circuit. It is made of heat-resistance steel and formed into shape. The precocious technique is popular in our company.
To prevent damage from workpieces, the high-aluminum firebrick is designed at the furnace bottom and furnace port. The expansion seam is pre-left with furnace lining. This kind lining structure has the following features: less heat storage, low thermo conduction coefficient, better insulation performance, few heat loss. Compare with firebrick, heat efficiency being improved by 18%. Skin temperature is less than ≤+35ºC.
3.3 Car Device
3.3.1 Car steel framework:
It consists of horizontal beam, vertical beam and bottom steel plate and welded together which forms as double layers of integral grid structure. The large I-steel rail also designed on this car system. The formed steel (same with horizontal beam) is welded with each horizontal beam. Such kind of rigid structure ensures an adequate strength under high temperature.
To prevent distortion under high temperature, edge plate (thickness:10mm) of car is made of casting steel (0Cr25Ni20Si2) , and expansion joint is pre-left.
3.3.2Car lining: it is fully made of alumina-silicate fiber. Service temperature can reach to 1000ºC, density: 180kg/m3 ,thickness: 200mm.
Car driving unit:
It adopts one set of 2.2 Kw motor. This unit consists of speed reducer, chain sprocket, chain, and wheel.
The wheel is made of ZG45# casting steel, it heat treated with queching process, totally 12 pieces of wheels is located bottom of car for smooth travelling.
Its main features are as following:
a. Long travelling distance: the wheels are mounted at bottom of the car which ensures the car can travel a long distance without limit from the rail.
b. Stable movement: the car travels on the steel rail.
c.Easy and flexible operation:
The car is driven by two speed reducers directly through gears. The speed reducers are equipped with brake, electric control and protection devices. Manual operating is enabled in addition to the automatic control through control panel. Easy maintenance is considered into design that motor adopts front flange connection, and working and non-working wheels adopts separate structure design
It adopts 0Cr25AL5 alloy. Each zone is mounted with 12 pieces of radiation tube. Power of each heating element is 6.5Kw. surface load is ≤2.6W/cm2
3.5 Circulating Fan:
5 sets of powerful centrifugal fans are designed on top of the furnace which to meet the temperature uniformity requirement and hot air can be circulated effectively inside furnace chamber. It consists of electrical motor, supporting structure, impeller, bearing, and shaft.
Electrical Motor: It is three phase motor of Y series. The motor is installed beside supporting saddle, The leather strap drives bearing spinning, such kind of driving method ensure impeller and bearing spinning in balance, reduce vibrating and less sound. The noise meets the GB87 standard.
Supporting Structure of Circulating fan: it is designed at center line of top furnace. It is used for support shaft and impeller. Bearing and bearing saddle are designed inside supporting case. Air cooling -off device is equipped under bearing saddle. The bearing is imported from Japan and has a long service life.
Impeller: It adopts centrifugal structure, the impeller is performed the static and dynamic balance test. Impeller, to prevent the impeller from being deformed, shaft and guide casing are made of heat-resistant steel.
Shaft: The long shaft connects two ends. One end which used for impeller is inside furnace, the other end which used for connecting leather strap is longer than supporting structure.
Bearing: it adopts adjustable bearing which imported for Japan. Such kind of bearing ensures circulating normally working for a long time.
Technical Data of circulating fan:
Air Volume: 19000-27000m3/h,
Air pressure: 1900-1400Pa,
Shaft of fan is made of 1Cr18Ni9Ti material which is imported from abroad. It adopts air cooling method which prolong its service life.
Guide Flow Plate
Guide Flow Plate: Hot air circulated in furnace efficiently, the guide flow plate reverts forced hot air circulated in furnace chamber which can meet temperature uniformity requirement. To ensure that the hot air circulating furnace coefficient above 0.8, centrifugal fan produces radial wind. Wind deflector can have a vertical radial wind maximum pitch value, press down the wind, from the bottom around the workpiece, and then inhaled by the fan, forms a loop circuit.
3.6 Sealing Device
Seal between furnace door and furnace body, furnace door and car, furnace body and car:
This section is the most important and difficult part to seal. framework of furnace door adopts light weight anti-deformation steel post and fixed with fiber. Bottom of furnace door is mounted with fiber block and the door is pressed tightly with furnace body by the pneumatic cylinder. With long experiences in manufacture this kind of car-bottom furnace, this is the most efficient method and most convenience way to seal.
The seal in these sections are most important to bogie type furnace, where the temperature loss greatly. It ensures the seal effects by adopting the following seal method: door frame is made of light weight distortion-proof steel structure and pneumatic compressing device is adopted, besides, refractory fiber seal blocks are designed at the bottom of furnace body, which is compressed and sealed with car automatically.
Furnace door is interlocked with the open and close of side seal.