Knowledge about Steel Production-II

Source: | Author:changxing | Published time: 1879 days ago | 1120 Views | Share:

Knowledge about Steel Production

11. What is magnetic flaw detection and ultrasonic flaw detection?
Place the test piece in the powerful magnetic field of the flaw detector to magnetize it, and then apply the suspension of iron oxide powder mixed with gasoline or alcohol to the surface of the test piece. At this time, the iron oxide powder gathers on those surfaces or under the skin. Place, this is the magnetic flaw detection.
Ultrasonic flaw detection is the use of the physical properties of ultrasonic waves to test low-fold tissue defects. This method can directly inspect the internal defects of steel, such as inspection of boiler tubes, and also check the internal quality of large forgings.
These two types of flaw detection are non-destructive tests.
12. What is the significance of the iron-carbon alloy phase diagram for rolling steel production?
Through the iron-carbon alloy phase diagram, it can be known which phase of the carbon steel heated to a certain temperature, and can analyze the structural transformation of the steel during the slow heating and slow cooling. Therefore, the iron-carbon alloy phase diagram is to determine the carbon steel heating. Reference basis for the rolling, final rolling temperature and carbon steel heat treatment process.
13. Briefly describe the behavior of unburned pulverized coal in a blast furnace.
(1) Participation in carbon gasification reaction
(2) Participation in carburizing reaction
(3) mixed in the slag, affecting the fluidity of the slag
(4) Deposition in the soft melt zone and the material column, deterioration of gas permeability
(5) With the gas escape outside the furnace
14. What should be the evaluation of iron ore quality from those aspects?
Ø The iron content of antimony ore is the most important criterion for evaluating the quality of iron ore;
Ø Harmful impurities in the ore, including the contents of S, P, Pb, Zn, As, Cu, K, Na, F, etc.;
Ø Reducing properties of bismuth ore;
Ø Softening characteristics of bismuth ore;
Ø The particle size composition of the strontium ore;
Ø The mechanical strength of the ore;
Ø The stability of the chemical composition of antimony ore.

15. What are the requirements for coke quality in blast furnace smelting?
1) The fixed carbon content is high and the ash content is low;
2) There are few impurities containing S and P;
3) The mechanical strength of coke is good and the heat strength is high;
4) The particle size should be uniform and the powder should be less;
5) The water should be stable.
16. What are the differences between sinter and pellets?
Sintering and pellets are methods of powder ore agglomeration, but their production process and the basic principle of solid sectioning are quite different. The effect of smelting on the blast furnace also has its own characteristics.
The differences between sintering and pellets are mainly reflected in the following aspects:
Ø Different requirements on the particle size of raw materials;
Ø The mechanism of tamping knots is different;
Ø The shape of the finished product is different;
Ø The production process is different.

Prev： Knowledge ......

Next： Knowledge ......