Technical Background for the Slag Stopper System
With the rapid development of steel industry, currently, users has increasingly higher requirement on the steel quality. Therefore, steel enterprise strives to manufacture steel product characterized by high quality, high technology, and high added value, to maintain competitive edge.
As we all known, to improve the molten steel quality, it is quite important to reduce the slag carry-over, which has been a knotty problem for steelmaking with BOF converter. Our slag stopper system is particularly offered for reducing the slag quantity during tapping.
The slag stopping system is a slide gate system installed at the tap hole of BOF converter. Based on the design philosophy of ladle sliding gate system for flow control, the slag stopper system is designed for slag control and includes a hydraulic drive system and an automatic slag detection system for intelligently control the opening and closing of the sliding gate. With the help of the slag control system, the slag elimination is completed simultaneously during tapping, to obtain molten steel containing no or little slag.
Features of the Slag Stopper System
1. More than 98% slag can be eliminated. The slag thickness in the ladle is no more than 40mm (excluding synthetic slag).
2. The slag stopping system operates stably and reliably. Conforming to safety and technological requirement, the accident rate is controlled within 1%.
3. The closing speed of the slide gate system is no more than 1s.
4. Efficiently, the replacement time of the slide gate plate is less than 15min/times (Excluding nozzle brick and manipulator).
5. Under normal circumstance, the service life of the slide gate plate and the outer slide gate is over 12 times, averagely (without liquid steel flow control function).
6. The inner slide gate can be used for over 40 times for synchronous replacement with tap hole. The separate replacement can be conducted for over 24 times’ application.
1. Slag stopper system
3. Rotary joint
4. Compressed air pipe for cooling
5. Water inlet and outlet pipes for cooling
6. High pressure oil pipe
7. On-line hydraulic power pack
8. Online stand for device replacement
9. Transhipment stand
10. Off-line hydraulic power pack
11. Column mounted jib crane
12. Three-position debugging stand
13. BOF converter
14. Forklift stand for transhipment
15. Maintenance and sliding plate installation area
16. System installation support
|Overall Dimensions (A×B×H)||mm||1470×1200×410||1780×1500×430|
|Sliding Plate Size (L×W×D)||mm||600×310×50/75||700×350×50/80|
|Tap Hole Dia.||mm||120/150||140/180|
|Oil Cylinder Stroke (L)||mm||230||280|
|Sliding Plate Replacement Form||-||Off-line||Off-line|
1. Water inlet 2. Oil outlet 3. Oil inlet 4. Water outletTechnical Parameters
|Oil Cylinder Dia.||125|
|Cylinder Pole Dia.||70|
|Working Medium||Aliphatic ester|
|Cooling Water Pressure||0.6Mpa|
|Seal||Imported high temperature resistant material|
The on-line hydraulic power pack requires two high pressure plunger pumps for normal operation. A spare pump shall be prepared, as well. The single motor power is 22kW. Equipped with control panel and hand lever operating unit, the hydraulic system can be controlled manually or automatically.
To eliminate limitation on the electric appliance control device, the hydraulic system for the slag stopper system is installed with hand-directional valve with large drift diameter and energy accumulator set for tapping in an emergency. Please refer to principle diagram for more details.
Working Pressure: 18Mpa
Working Medium: Aliphatic ester
Oil Tank Capacity: 1m3
Hydraulic System Cleanness: NAS9
Auxiliary Equipment for the Slag Stopper System1. Off-line Maintenance Equipment
1) 1×BZ2-00 column mounted jib crane
2) 1×three-position debugging support
3) 1×off-line hydraulic power pack
4) 3×off-line oil cylinder
2. Transhipment Stand
Upon the completion of sliding plate replacement, the slag stopper system shall be put on the transhipment stand and delivered to the converter by forklift.
3. Replacement Installation Stand
Our slag stopping system shall be hoisted through the electric block on the replacement stand, and slides along the pathway to the tap hole. Then, the slag stopper system can be installed on the tap hole within 15 minutes.
1. Slag Stopper System Installation Stand
2. Working Platform
|1||Cooling Water||Cooling for water-cooled oil cylinder||10m3/h||-|
|Cooling for on-line hydraulic power pack||6m3/h||-|
|2||Compressed Air||Spring cooling||60m3/h||0.6-0.8Mpa|
|Pneumatic impact wrench||60m3/h|
|3||AC||On-line hydraulic power pack||22kW×3||AC380V|
|Off-line hydraulic power pack||7.5kW|
|Replacement stand in front of converter||10kW|
1. Steel ladle top edge elevation
2. Trunnion elevation of converter
3. Converter mouth elevation
4. Diameter of movable and fixed hood, movable hood lowest elevation and lift range
5. Diagram for converter shell and trunnion ring