|
Two-floor cast house platform
- Two-floor cast-house platform is built after clearing the old one to the concrete plates, which could be used for constructing of main trough foundations, walls near tilting runners, collumns and girders of the horizontal 2nd floor.
- Hence, the safety of movement on the platform is increased, the free movement of equipment is possible.
Design of cast house main trough
The products of melting (pig-iron and slag) run together from the tap hole of the BF into the main trough. There the separation of pig-iron and slag happens.
The construction of bath type main trough helps to avoid the loss of pig iron and also to prevent slag from running into hot-metal ladle. 
Covers for main trough
The flue gases are collected directly at the sources using the equipment of the aspiration. At the start moment of the tapping the tap hole of the BF is the source of flue gases. The interaction of oxygen with liquid metal is present; hence the brown smokes generates. This process could be prevented by the covering the main trough. The flue gases are collected into suction hoods.
Covers for transport runners
The pig-iron and slag run in the covered transport runners to the tilting runners.
Openings of the tilting runners
Openings of the tilting runners are also covered, which helps to avoid oxygen access to melting.
The space of the tilting runners is the main source of flue gases
and requires suction of large flue gases amounts.
Evacuation is done by hoods implemented in the wals of tilting runners. 
Refractory materials
The open space between 1st and 2nd floors enables the cooling of the main troughs and transport runners shell by the air.
This is the principle of increasing the service life of refractories of any quality. 
Hydraulic drills in the cast house
For optimum tapping it is necessary to create the calibration channel of the tapping hole, which is enabled by using a modern hydraulic clay gun. The equipment consists of three parts: anchoring mechanism, drilling mechanism and turning mechanism. The anchoring mechanism can be hydraulic or pneumatic. The drilling and turning mechanisms are hydraulic. For drilling, th crowns are used, which create a precise tap hole. Besides accurate geometry of the hole, the hydraulic drill secures high quality of the surface of the tap hole. Drilling enables creation of the hole under difficult conditions. During drilling, the drilling crown is cooled by compressed air, which also removes the drilled material. Hydraulic aggregate is used for the drills as well as for the clay guns.
Hydraulic clay guns in the cast house
Hydraulic clay guns, compared to electric clay guns, have the following advantages:
durability of the roller for gunning material as well as the main hydraulic roller is more than 8 years (for electric clay guns it is max. 2 years) reliability of the tap hole gunning is 100 %, while the electric drive is unable to overcome the great resistance of the gunning material no need for auxiliary equipment for mounting of the clay gun, which frees the place in the area of tapping hydraulic clay gunss make only two movements – turning and piston movement, while electric guns make 3 movements hydraulic station can be used also for the drill and the manipulator constructional height of the hydraulic clay gun is lower than of the electric one; that enables placement of a work platform above the tap holes reliability of the equipment operation enables increase of safety during tapping high costs of hydraulic clay gun purchase are to be returned in the first half of the BF campaign, which is a consequence of decrease in repair costs.
Hydraulic manipulator
It is possible to manipulate the removable section of the main trough cover via a separate manipulator. The removable section of the main trough is removed while the drill or the clay gun are operating. The manipulator arm contains catching equipment. With its help the manipulator lifts the cover section. By turning of the arm the section leaves the operation area for the drill and the clay gun. While the clay gun or the drill are in operation, the section is hanging on the manipulator arm. After finishing the drilling or gunning of the tap hole, the section is taken back to its place. It is possible to use one manipulator for the cover of both main troughs in the cast house. The manipulator is anchored to a foundation which is placed at the platform (1st floor). The operation of the manipulator is through remote control. Load-bearing capacity is 20 t.
Advantages of the manipulator:
catching of the manipulator is automatic, without the personnel intervention, and the placement is carried out in the precisely set place. hydraulic source is the same as for other equipment of the casting facility
Electrostatic precipitator
Electrostatic precipitator consists of:
the body itself, the system of high voltage and collecting electrodes, the system of shaking, the funnel, input and output parts.
Working underpreasure before the electrostatic precipitator is approx. 3000 Pa, the maximum temperature +350 st.C.
Fan
Separate parts of equipment are controlled with controller on the basis of changes in separate tapping phases and also on the base of measurement of the dust content in the chimney.
During tapping when the aspiration of the slag tilting runner is on as well, the fan electric motor works with maximum turns, and between taps it works with minimal turns, which helps to save electrical energy.
The fans are equipped with the ventilator work display (VWD) and non-stable state indicator. VWD monitores the level of vibrations in the rotating parts and the temperature of bearings.
Usually when a big repair of BF is performed, also some repair of the cast-house floor is undertaken. Money and manpower used for rebuilding of the cast-house floor in its original state could be well enough for transforming it into a modern one, up-to-date with current standard.
Transport runners
The pig iron runs from the main trough to the ladle through the transport runners.
The temperature decreases by 10-20C during run. Temperature drops will be reduced if the runner system is shortenned and main troughs and runners are covered. Covering the runners limits the oxygen supply, which reduces the generation of brown fumes and allows to activate full aspiration of the cast house with smokes cleanin during the tapping. This solution solves the problems of work safety and ecology.
The aspiration ducts
The aspiration ducts are placed between the 1st and the 2nd floors of the cast house, without occupying additional space on the working platform, which improves the cast house architecture.
Steel structure of electrostatic precipitator
The dust density in sucked fumes is 0.25 – 1.5 g.m-3. Amount of dust gathered in the electrostatic precipitator from cast house aspiration is 0.9 – 1.1 kg/ton of pig-iron. The dust density in the chimney does not exceed 50 mg x m3.
The idea of modern two-floors cast house platform is in making it a cast house floor where:
An optimal equipment set for the aspiration system includes:
the suction hoods of tap holes, skimmers and tilting runners. the ducts with dampers placed between the 1st and the 2nd floors of the cast house the electrostatic precipitator the fan, electric motor with frequency converter and transformer the chimney
«West-Sibirian Steel Corporation» BF № 2
Cast-house floors reconstructed by Mi-Fi-Bu SKELETING, spol.s r.o.
|
)
)
)
)
)
)
)
)
){kind=small}
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
)
