The principle of adjusting and controlling the gun position in the early stage of blowing is:
The slag is melted early, and the slag is melted well in order to maximize the removal of (phosphorus).
The oxygen transfer methods in the oxygen top-blown converter generally include:
There are two ways of (direct oxygen transmission) and indirect oxygen transmission.
Steelmaking temperature control refers to
Correctly control the temperature and (end point) temperature of a furnace of steel.
The root cause of slag drying back is
The carbon-oxygen reaction is fierce, and the slag (FeO) is greatly reduced.
Which three layers of concentric steel pipes consist of the oxygen lance
The inner pipe is the (oxygen) channel, the cooling water (inlet) channel between the inner tube and the middle tube, and the cooling water (outlet) channel between the middle tube and the outer tube.
The main reasons for the damage of the lining are
The role of high temperature heat flow, the role of (quick cold and rapid heat), the role of (mechanical shock), chemical erosion and other aspects.
The main purpose of lowering the lance at the end of converter smelting is
uniform molten steel temperature and (composition).
Methods to control the carbon content of molten steel at the end point are
There are three kinds of carbon drawing method, high drawing filling method and (carbon increasing method).
The automatic control of the oxygen top-blown converter steelmaking process is divided into
(Static control) and dynamic control.
Mach number is
The ratio of the air velocity to the (speed of sound) under local temperature conditions.
What is a reasonable nozzle structure
A reasonable nozzle structure should maximize the conversion of the oxygen stream (pressure energy) into kinetic energy.
In order to achieve the purpose of balanced erosion of the furnace lining and prolong the furnace life, use
(Comprehensive furnace building).
The main role of the secondary gun is
(Temperature measurement), (Sampling), (Carbon determination), (Oxygen determination), (Measuring liquid level), it brings the advantages of reducing labor intensity, shortening smelting time, and easy to realize automatic control.
The main factors affecting the refractoriness of the converter final slag are
(MgO), TFe and alkalinity (CaO/SiO2).
Oxygen flow refers to
The amount of oxygen supplied to the molten pool per unit time (volume).
What is the effect of excessively high molten steel temperature?
If the temperature of molten steel is too high, the (solubility) of the gas in the steel will be too large, and the greater the impact on the steel.
Refractories with (CaO) and (MgO) as the main components are
Alkaline refractories.
In the slag splash protection process, in order to make the slag splash layer have sufficient refractoriness, the main measure is to adjust
The content of (MgO) in the slag.
The main contents of the oxygen supply system include:
Determine the reasonable (nozzle structure), (oxygen supply intensity), (oxygen pressure) and (gun position control).
The slagging system is determined to be appropriate
(Method of slagging); type of slag; quantity of slag; adding time and measures to accelerate slagging.
The deoxidizing ability of deoxidizing elements refers to
At a certain temperature, it is the concentration of oxygen in molten steel (equilibrium state) with a certain concentration of deoxidizing elements.
What is the effect of adding alloy to molten steel?
The freezing point of molten steel is (decreased).
The blowing mode with low blowing gun position or high oxygen pressure is called
(Hard blow).
What is the composition of the oxygen lance?
(Nozzle), gun body, gun tail.
The oxygen supply per ton of metal per unit time is called
(Oxygen supply intensity), its common unit is (standard m3/ton.min).
The performance requirements for refractory materials in converter production are:
Refractoriness (high), resistance to sudden temperature changes, strong resistance to slag and molten steel corrosion, stable high temperature performance and chemical performance.
Features of converter flue gas:
(high temperature), (large gas volume), (large dust content), the gas has (toxic) and (explosive).
The current treatment methods for converter flue gas are
(burning method) and (unburning method) two kinds.
The average amount of flue gas per ton of steel in the unburned method (standard state) is
(60-80m3/t), the flue gas volume of the combustion method is (4-6) times that of the unburned method.
The converter flue gas purification system can be summarized as
There are three parts of flue gas (collection and transmission), (cooling and purification), (extraction and release).
The converter flue gas purification methods are
(full wet method), (dry and wet combined method) and (full dry method) three forms.
What are the three parts of the venturi purifier?
(Atomizer), (Venturi tube body) and (Dehydrator) composed of three parts.
What are the three parts of the venturi body?
(Contraction section), (throat section), (expansion section) are composed of three parts.
Venturi tubes can be divided into structures
(Sizing Venturi) and (Adjusting Venturi).
Which three main systems are included in the converter gas recovery process?
There are three main systems (converter gas cooling system), (converter gas purification system), and (converter gas recovery system).
Under normal circumstances, when is dephosphorization mainly carried out?
Smelting (preliminary) is carried out.
The main purpose of bale protection pouring is:
To avoid (secondary oxidation).
The operation of adding one or several alloying elements to steel to meet the requirements of finished steel composition is called
(Alloying).
What is the root cause of splashing during steelmaking?
The explosive carbon-oxygen reaction in the steel-making molten pool and the instantaneous generation of large amounts of (CO) gas is the root cause of the splash.
Oxygen top-blown converter steelmaking decarburization mainly depends on
(oxygen supply strength) and bath temperature.
The thermodynamic conditions for dephosphorization are
High alkalinity, (high iron oxide) and moderately low temperature.
Adding Al to killed steel is to
Ensure complete deoxidation and refinement (grain).
The cause of splashing is
An explosive (carbon-oxygen) reaction is produced and carbon monoxide gas emission is blocked.
The current methods of flue gas purification are
(combustion method) and unburnt method.
The presence of sulfur in steel can improve the
(cutting) performance.
For high-quality carbon steel, the phosphorus content is required to be controlled within
(0.035%)% or less.
The main difference between rimmed steel and killed steel is
(The degree of deoxygenation is different).
Industrial "three wastes" means
Waste water, waste gas, (waste residue).
What are the characteristics of active lime:
(High porosity, large specific surface, fine crystal grains) and other characteristics, so it is easy to melt, and the slag formation speed is fast.
Three off in the pretreatment of molten iron refers to
(Desiliconization, Dephosphorization, Desulfurization).
The air supply components at the bottom of the compound blowing can be divided into
(tube type) and (breathable brick type) two types.
The relationship between the (melting point) and (composition) of the slag is shown graphically. This kind of graph is called
The phase diagram of the slag.
(Mold) is called
The heart of the continuous casting machine.
In order to provide qualified molten steel for continuous casting, what must steelmaking be strictly controlled?
Strictly control the composition of molten steel, especially the (sulfur), (phosphorus) and (gas and non-metallic inclusions) in steel must be controlled to the lowest level possible to improve the cleanliness of molten steel.
The main internal defects of continuous casting slab are:
(center looseness, shrinkage cavity, center crack, middle crack, subcutaneous crack, subcutaneous bubble, center segregation, slag inclusion) etc.
The main measures to improve the purity of continuous casting molten steel are:
Steelmaking (providing pure molten steel), using molten steel (refining treatment outside the furnace) and (continuous casting protection casting)
The internal structure of the continuous casting billet of killed steel can be divided into
(surface equiaxed crystal) belt, (columnar crystal) belt and (central equiaxed crystal) belt.
Industrial steel is generally divided into chemical composition
(carbon steel) and (alloy steel) are two major categories.
Main sources of non-metallic inclusions in steel:
Raw materials, slag, furnace lining, cast refractory, (deoxidation product), (secondary oxidation) in the production process.
The main functions of refining outside the furnace are:
Adjust (temperature, composition) to remove (inclusions and gas) in steel.
The structure of the gas supply element at the bottom of the combined blowing converter has
(Casing nozzle type), brick joint combination type, (thin metal tube porous type), etc.
Commonly used desulfurizers for desulfurization outside molten iron furnace are:
Lime, (calcium carbide), (magnesium granules).
The thermal effects of coolant include:
(the physical heat consumed by the coolant to increase the temperature) and (the chemical heat consumed by the coolant to participate in the chemical reaction).
The commonly used deoxidation methods for steelmaking are:
(precipitation deoxidation method), diffusion deoxidation method, (vacuum deoxidation method).
When the combined force of [H] in the small pores and microstructure stress exceeds the strength of the steel, what will happen during rolling?
(white dot).
The desulfurization methods of converter steelmaking are
(Slag Desulfurization) and (Vaporization Desulfurization).
The commonly used deoxidation methods for steelmaking are
(precipitation deoxidation), (diffusion deoxidation), and (comprehensive deoxidation).
The reaction of [Mn]+[O]=( MnO) is
(exothermic) reaction.
The use of light reduction technology is mainly
Improve the (center segregation) of the slab.
When the length of the two diagonals on the cross section of the billet is not equal, it is called
(off party).
Longitudinal cracks belong to
(surface) defects.
Requirement for tilting angle of converter body
It can rotate (360) degrees in both directions.
When the temperature of the molten pool is low during the smelting process, it can be used
(Ferrosilicon), aluminum block temperature increase.
The five major systems of converter steelmaking are
(loading) system, (slagging) system, (temperature) system, oxygen supply system, endpoint control and deoxidation alloying.
Common gases in steel are,
(oxygen), (nitrogen), and (hydrogen)
Segregation in slab refers to
The distribution of billet (chemical composition) and (gas and inclusions) is not uniform, but usually refers to the uneven distribution of (chemical composition).
In what form does carbon mainly exist in steel?
It exists in steel in the form of (Fe3C) and is the main element that determines steel (strength).
The splash produced in converter steelmaking can be divided into
(Explosive splash), (Foam slag splash), (Return to dry metal splash).
During the blowing process, the principle of controlling the process temperature is
During the blowing process, the principle of controlling the process temperature is
According to the different degree of deoxidation, steel can be divided into
(killed steel), (semi-killed steel) and (rimmed steel).
The technical standards of products can be divided into
(National Standard), (Industry Standard), Enterprise Standard, etc.
Phosphorus in molten steel is a harmful element, what can it make steel
(cold and crisp).
Sulfur in molten steel is a harmful element, what can it make steel
(hot and crisp).
The melting loss mechanism of the bottom air supply element is mainly
(bubble counterattack), (water hammer erosion) and (pit melt loss).
Part of the metal is lost during the converter steelmaking process. This part of the metal lost during the (conversion) process is called
Blow loss.
(Bottom air supply element) is the core of combined blowing technology,
(Nozzle type) and (brick type).
The main factors affecting the fluidity of molten steel are
(temperature), (composition) and (inclusions in steel).
The oxygen transfer carrier of the oxygen top blowing converter is
(Metal droplet transfers oxygen), (Emulsion transfers oxygen), (Slag transfers oxygen) and (Iron ore transfers oxygen).
The main forms of converter steelmaking desulfurization are
(Slag desulfurization), gasification desulfurization, and out-of-furnace desulfurization.
The main factors affecting slag viscosity are
Temperature, solid particles in the slag, (slag composition).
The main factors affecting slag viscosity are
Temperature, solid particles in the slag, (slag composition).
The oxidation reaction of silicon is
(exothermic) reaction, low temperature is conducive to the oxidation of silicon.
Commonly used deoxygenation methods are
There are three types: precipitation deoxidation, diffusion deoxidation, and (vacuum deoxidation).
When the oxide decomposition reaction reaches equilibrium, the pressure of the generated gas is called
(decomposition pressure).
In Q235A, A means
Steel (quality grade).
Substances that can significantly reduce the surface tension of liquids are called
(Surface active substance).
The main raw materials for top and bottom combined blowing converter steelmaking are
Hot metal and (scrap steel).
According to the Fe-C phase diagram, the ferroalloy with carbon content (0.0218%～2.11%) is
Steel.
The nozzles of the converter oxygen lance are mostly
(Laval) type porous nozzle.
Commonly used industrial steelmaking methods are
(converter steelmaking method), electric arc furnace steelmaking method, open hearth steelmaking method.
The loading system of the converter is
Quantitative loading, (fixed depth loading), (quantitative loading in stages).
The heat released during the transformation of steel from liquid to solid and subsequent cooling includes
(Overheating of molten steel), (Latent heat of crystallization) and (Sensible heat of ingot (slab)).
The characteristics of the secondary oxide of molten steel are
(complex composition), (large particle size), (irregular shape), accidental distribution.
The main cause of segregation
(Difference in solubility of elements in liquid and solid state), (cooling rate), (diffusion rate), (convective flow of liquid phase).
Under what atmosphere is the hot metal dephosphorization reaction in hot metal pretreatment?
(oxidizing) in an atmosphere.
Inclusions in steel can be divided into
Do not deform inclusions, (brittle inclusions), (plastic inclusions).
The factors affecting the alloy yield are:
tapping temperature, (oxygen content in molten steel), tapping port situation, amount of slag entering the ladle, alloy particle size, alloy input sequence.
The stirring of the converter bath is conducive to improving the kinetic conditions of smelting, and its sources are mainly
(C-O reaction) A large number of CO bubbles are generated to stir the molten pool during the floating process, and the other is (the stirring of the external gas blowing).
The slag can be divided into:
Oxidation slag and (reduction slag).
The actual oxygen content of the converter molten steel is always (greater than) the oxygen content in equilibrium with the carbon, and the difference is called
The oxidation of molten steel.
Inclusion means
The (non-metallic) phase produced or mixed into molten steel during smelting and pouring solidification.
Surface active substances can significantly reduce the liquid
(surface tension).
The adsorption of other liquid media on the surface of a solid or liquid is called
(Adsorption).
The molecular formula of the low-melting point produced by calcium treatment of aluminum killed molten steel is
(12CaO.7Al2O3).
The main components of fluorite are
(CaF2 ).
The three vertex angles of the ternary phase diagram represent
(three pure components) and its melting point.
What form does phosphorus exist in steel
([Fe2P], [Fe3P) forms exist.
The eutectic transition temperature in the Fe-C phase diagram is
(1148℃).
The main indicators of white slag in LF furnace are:
((FeO)<1.0% and MnO<0.5%).
The role of the continuous casting straightening machine is
(drawing), (straightening), sending starter.