The working principle of ladle nozzle
The sliding nozzle device is composed of upper and lower sliding
plates made of refractory materials and mechanical driving
structure, which is installed outside the bottom of the ladle. The
upper slide is fixed and the lower one is movable. According to the
action mode of skateboard, it can be divided into three types: 1)
linear reciprocating; 2) linear propulsion; 3) rotary. When the
casting holes on the upper and lower slide bricks are staggered,
the upper nozzle hole is filled with drainage sand, and the ladle
can be filled with steel; when the casting holes overlap, the
drainage sand will flow out automatically, and the pouring speed
can be controlled by the overlapping degree of casting holes.
The slide plate is the key component to determine the function of
sliding nozzle, which plays the role of controlling and regulating
the flow rate of molten steel. Due to repeated contact with high
temperature molten steel (especially at the casting hole), the
sliding plate suffers from severe corrosion and severe service
conditions. The slide plate is required to have good performance
such as high strength, corrosion resistance and anti spalling.
Properties of sliding plate
(1) smoothness of sliding surface ≤ 0.05mm;
(2) high mechanical strength
(3) It has strong corrosion resistance to molten steel and slag;
(4) excellent oxidation resistance;
(5) good thermal shock stability.
The sealing protection of ladle sliding nozzle is mainly at the
joint of upper nozzle and upper sliding plate, and lower sliding
plate and lower water inlet. During the pouring process, the lower
slide plate and the lower nozzle must be replaced and reassembled
after pouring one or two heats of molten steel. In order to ensure
the high cleanliness of the molten steel and the uniformity of the
internal quality of the billet, the sealing protection adopts fiber
or clay sealing gasket.
The structural principle of Tundish Nozzle:
The tundish nozzle is a combination of inner core and exterior. The
inner core is made of stabilized zirconia and zircon sand,
producing through molding machines and high-temperature
calcination. The exterior is made of zirconium and corundum,
producing through molding machines and low-temperature baking.
Tundish nozzle is located at the bottom of the tundish, it's the
channel of liquid steel to flow from the tundish into the
crystallizer.
Features of Metering Nozzle/ Refractory Nozzle/ Refractory Tundish:
1.Low expansion, supprior resistance to erosion/corrosion and
thermal shock cycling.
2.Long and extended casting sequence times
3.Controlled and stable casting speed
4.Resistance to oxygen lancing
Our high purity and density ZrO2 tundish nozzle have the excellent
shock stability, strong errosion resistance, durable working time
etc features. Our tundish nozzles are different from the one of
Inida, UK, Germany, etc. origin. We have the high density of
5.4g/cm3, taking the special material and technology, automatic
production equipment, enough firing time, then excellent property
than them. For the tundish nozzle inserts, we have making testing
on 150tons ladle for 95% zirconia products, our tundish nozzle can
keep working 10-12 hours, even longer.
Our High performance 95% tundish Zirconia upper nozzle has the high
purity and density, excellent erosion, thermal shock stability,
crushing resistance, etc. feature. Tundish nozzles are mainly
control the steel liquid flowing amount into the mould.
