Industrie- & Anlagenbau - Bad Königshofen Continuous plant / Hardening furnace → Consisting of the process stages: Hardening, post-treatment and tempering

Year of construction: 2001

General:
2001-2023 production-accompanying exchange of wear parts.
Availability over the year 90
Control system: S5
Current plant technology: Pusher-type furnace (made of cast steel)
Output during quenching and tempering max. 300 kg/h 
Output during carbonitriding max. 100 kg /h

The plant consists of the 7 main components:
Continuous annealing furnace, quenching bath, oil storage tank, de-oiling and washing station; manipulator, continuous tempering furnace, control cabinet / infrastructure.

Functionality of the continuous annealing line:
- the plant is capable of quenching and tempering and carbonitriding on oil bath basis
- process temperatures up to 930°C
- Base or safety gas: (for O2 closure) nitrogen/methanol (as carbon donor) is used
- process gas: natural gas or ammonia but convertible to propane
- the curing area is heated with natural gas
- the tempering furnace is powered by electricity
- the round wire link belt has a width of 765mm (1.4864 Nb)

1. continuous annealing furnace:
- Model: DOBGS 7.5 1 50-10-0 (intermittently conveying, protective gas-tight outer shell, indirectly heated with recu - radiant tube burners.
- Outer dimensions: Continuous furnace L x W x H = 7.85 x 2.10 x 2.25 m → annealing zone length 5.0 m; conveyor belt width: 765 mm.
- Temperature: max. 980 °C +/- 5 K
- Total heating power: 210 kW - by means of 14 Noxmat - steel tube burners manufacturer ALD with a radiant tube diameter of 150 mm.
- temperature control zones: 3 heating and control zones (i.e. zone1 - 6 x 15 = 90 kW; zone2 - 4 x 15 = 60 kW; zone3 - 4 x 15 = 60 kW)
- Protective gas supply / control: 3 x each nitrogen, methanol, natural gas, ammonia air
- Throughput speed: adjustable via frequency converter 2 to 7 m/h
- Furnace time: approx. 75 min at 4m/h; adjustable from 38 to 135 min; holding time 50 min at 4m /h
- Transport equipment: Round wire link belt made of 1.4864 with 18 mm lamellar edge
- Inert gas consumption: inert gas: nitrogen approx. 3 m3/h; methanol 3 l/h, natural gas 500-2000 l/h, ammonia 200-300 l/h, air 500 l/h
- Lining: is lined with fireclay, ceiling with thermal insulation wool, condition: in need of repair
- Electrical connected load approx. 10 kW 
- Total weight approx. 15.800 kg

2. quenching bath model KAB 11,1:
- suitable for quenching with oil
- Structure: electrically driven circular conveyor, level difference detector, lifting platform, basket turning device, bath heating, bath circulation, water cooling and draining station.
- External dimensions: L x W x H = 2.80 x 2.50 x 2.00 [m]; drop height in quenching oil = 1.0 [m]. 
- Total weight with oil: approx. 16,000 [kg].
- Connected load heating: 48 kW
- oil cooler HK4 - make Hering 2 x 2,2 kW
- incl. level - difference detector model NDM 100-0

3. oil reservoir model B12,5:
- Suitable for holding the oil from the quenching bath with pump and support frame for centrifuge system.
- External dimensions: L x W x H = 4.20 x 2.50 x 1.55 m; max. filling height 1.40 m; max. volume 12.88 m3

4. de-oiling and washing station:
- consisting of 1x centrifuge AZ 500 manufacturer WMV, 1 x washing machine WA 500, 1 x centrifuge AZ 500 H for drying. 
- 8 cylindrical transport containers according to drawing 300 /864 /96 - drum height 500mm
- connected load: ca 15 kW

5. manipulator model MBM 63/1 - (500):
- consisting of a mechanical cross slide for 6 positions and of a mechanical lift for 3 positions
- a pneumatically operated pincer to pick up the basket incl. the emptying of the baskets by a separate tilting station

6. electrically heated continuous tempering furnace model DOBE 11 1 49-6,5-0:
- continuously conveying, directly heated with E - heating elements.
- Outer dimensions: L x W x H = 7.55 x 2.35 x 2.60 m; tempering zone length = 4.9 m 
- Operating temperature: max. 650 °C +/- 5 K
- Throughput speed: adjustable via frequency converter 1.9 to 9.8 m/h
- Furnace time: approx. 120 min at 2.45 m/h; adjustable from 30 to 154 min; holding time 90 min /h
- Total heating capacity: 110 kW - 2 heating inserts per zone
- Temperature control zones: 3 heating zones (i.e. zone1 - 2 x 25 = 50 kW; zone2 - 2 x 15 = 30 kW; zone3 - 2 x 15 = 30 kW)
- Connected power hot air circulator: 6,6 kW
- Transport equipment: round wire link belt made of 1.4864 with 50 mm lamellar edge

7. control cabinet:
- Outer dimensions: W x D x H = 4.60 x 0.60 x 2.05 m 
- total power: 210 kW
- Control system: Siemens S5