Method for casting high-quality castings through blast furnace molten iron with short process

A blast furnace hot metal, short process technology, applied in the field of metallurgical casting, can solve the problems of low mechanical properties of castings, uneven solidification structure, uniform structure of cast iron, etc.

Active Publication Date: 2017-09-01
磐石华兴汽车零部件制造有限公司
View PDF5 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] However, the short-flow process also has the following disadvantages: (1) It has long been found that there are more supercooled D-type and E-type graphite in the solidification structure of molten iron in the short-flow process than in the conventional process. Coarse flaky graphite; (2) Short-process smelting Due to the use of molten iron in the blast furnace as the charge, graphite is easy to aggregate, so the solidification structure is uneven and the mechanical properties of the casting are low

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for casting high-quality castings through blast furnace molten iron with short process
  • Method for casting high-quality castings through blast furnace molten iron with short process
  • Method for casting high-quality castings through blast furnace molten iron with short process

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0051] In the intermediate frequency furnace, first put the returned material and scrap steel, and pour the blast furnace molten iron into the intermediate frequency furnace, and the blast furnace molten iron exchanges heat with the returned material and iron-containing waste to solidify the molten iron; the blast furnace molten iron accounts for 50% of the total weight of all materials in the intermediate frequency furnace , the scrap steel is 20±1% of the total weight of the blast furnace molten iron, and the rest is returned charge and ferroalloy; the described return charge is waste casting; the blast furnace molten iron exchanges heat with the return charge and scrap steel in the intermediate frequency furnace, and the blast furnace molten iron has a solidification process , Partial solidification of blast furnace hot metal in contact with return charge and scrap steel;

[0052] Before the materials in the intermediate frequency furnace are completely solidified, start the...

Embodiment 2

[0058] Method is with embodiment 1, and difference is:

[0059] (1) The molten iron in the blast furnace accounts for 55% of the total weight of all materials in the intermediate frequency furnace; the returned material is the pouring riser;

[0060] (2) Add ferrosilicon alloy and ferromanganese alloy so that the weight percentage of silicon in all materials in the intermediate frequency furnace is 1.7%, and the weight percentage of manganese is 0.55%, and then heat up to 1545°C; add carburant to control the carbon in all materials The weight percentage is at 3.0%;

[0061] (3) The molten iron in the intermediate frequency furnace is kept at 1545°C for 14 minutes;

[0062] (4) The amount of inoculant is 0.55% of the total weight of all materials in the ladle;

[0063] (5) The obtained gray cast iron contains C 3.3%, Si 1.9%, Mn 0.7%, S≤0.08%, P figure 2 As shown, the tensile strength is 269MPa, and the hardness (HB) is 176.

Embodiment 3

[0065] Method is with embodiment 1, and difference is:

[0066] (1) The blast furnace molten iron accounts for 60% of the total weight of all materials in the intermediate frequency furnace; the said returned materials are waste castings and pouring risers;

[0067] (2) Add ferrosilicon alloy and ferromanganese alloy, so that the weight percentage of silicon in all materials in the intermediate frequency furnace is 1.6%, and the weight percentage of manganese is 0.6%, and then heat up to 1550°C; add carburant to control the carbon in all materials The weight percentage is 3.4%;

[0068] (3) The molten iron in the intermediate frequency furnace is kept at 1550°C for 13 minutes;

[0069] (4) The amount of inoculant is 0.6% of the total weight of all materials in the ladle;

[0070] (5) The obtained gray cast iron contains 3.3% of C, 1.9% of Si, 0.7% of Mn, S≤0.08%, P<0.15%, 0.3% of Cr by weight percentage, and the balance is Fe and unavoidable impurities; the structure is Pea...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
tensile strengthaaaaaaaaaa
tensile strengthaaaaaaaaaa
tensile strengthaaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for casting high-quality castings through blast furnace molten iron with a short process. The method comprises the following steps that (1) foundry returns and steel scraps are placed into an intermediate frequency furnace at first, and the blast furnace molten iron is poured into the intermediate frequency furnace; (2) an intermediate frequency furnace power source is switched on before solidification, and ferrosilicon and manganeisen are added at 1350+/-10 DEG C; (3) heat preservation is conducted for 13-15 min at 1540-1550 DEG C; and (4) a nucleating agent is put in, iron of the molten iron is removed, drossing pouring is conducted, grey castings are obtained, a nodulizing agent is placed in a ladle, part of molten iron is subjected to iron removal and nodulizing treatment, remaining molten iron is added after drossing, the nucleating agent is injected, drossing pouring is conducted, and nodular cast iron is obtained. Through cooling treatment during smelting, alloy adding time adjustment and molten iron superheat control, graphite structures are refined, and the casting quality is improved while the technological process is shortened.

Description

technical field [0001] The invention belongs to the technical field of metallurgical casting, and in particular relates to a method for casting high-quality castings in a short flow of molten iron in a blast furnace. Background technique [0002] As the basic industry of the machinery industry, casting has a very large market demand for castings. Since the reform and opening up, the foundry industry, like all other industries, has developed greatly. The output of castings continues to expand, and new technologies and processes continue to emerge. In 2015, my country's annual output of castings was 45.6 million tons, making it the world's largest producer of castings. The development of the automobile industry determines the market demand for automobile castings, and the output of automobile castings accounts for about 27% of the total output of iron castings. [0003] The "short process" process is one of the optimization technologies promoted by the National Foundry Asso...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C21C1/10C22C33/08C21C7/00
CPCC21C1/10C21C7/00C22C33/08Y02P10/20
Inventor 柳立民张国志董怀福彭东程乐李海航
Owner 磐石华兴汽车零部件制造有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products