Three Levels Of The Cast Iron Ball Hardness And Toughness

Domestic large and medium-sized ferrous metallurgy mine concentrator

, finely ground generally use cast iron ball. The fine grinding process for grinding stripping, impact, supplemented, do not insist on grinding balls have a high impact toughness. Measure the manufacturing point of view from the grinding balls, iron balls (except the high-alloy iron ball) low initial cost, on concentrator attractive. Cast iron ball according to the evaluation of hardness, toughness, and two indicators can be divided into three levels, namely low, medium and high third gear. (1) Low-grade iron ball. To so mm, for example, impact value of = 2.94 J/cm2, about the surface 0 to 5mm Rockwell hardness HRC 28-32, core hardness of HRC 15 20, commonly known as ordinary cast iron, white iron. Ball of the fracture surface was silver and white, the microstructure of a pearlite; ledeburite heart, grayish black, the microstructure for the iron chain + pearlite. Typical of ordinary cast iron ball to choose all the national standard cast iron, cast 14 cast 18 mm ball fracture in dso and white who have a 3mm. 30h ~ 5% scrap appropriate to add a slight improvement in the toughness of the iron ball. If you cast 14 a cast on the basis of 18 accounted for 80% of the amount of white mixed with 20% of the steel-making pig iron, iron ball fracture layer for 3-7mm. The cooling rate is too fast, the whole body is white. This low-grade iron ball low hardness, toughness poor investment in mill use, damage rate up to lOclo a 25clo. Grinding balls residues roundness is not good, mostly gravel-like. For the lattice-type mill, the total pitching the amount of residue excretion 30clo 40%; for overflow type mill grinding efficiency by 5% to 8%. Even so, some large and medium-sized iron processing plant is still in use. (2) Mid-range ball. The case of alloying iron ball areas, Mn-containing magnesium ductile iron ball, in line with the GB 3180 - 82 the provisions of technical conditions, otherwise low-chrome ball. In recent years, the new mid-range ball - a natural multi-element low-alloy quenched iron ball (referred to as the quenching ball). Shougang Mining Company on behalf of the quenching sphere of production used in all GB9949 - 88 Phosphor Bronze Titanium low-alloy cast iron, to be the chemical composition of the adjustment on this basis, according to the size of the ball diameter, and quenching and heat treatment. Quenching ball useful alloy elements contained in more than 20 species, mostly inherent in the smelting of pig iron sinter. Therefore, the chrome ball, low-chromium ball in manganese, rare earth magnesium ductile iron ball quenching the ball high and low production costs, performance and low chrome ball, all kinds of manganese ball comparable. The microstructure of the matrix of martensite (70qo 75%) + phosphorus eutectic carbides + a small amount of sorbite. Impact toughness, the value of 9-7 8J / c Ding 12, the hardness value according to the needs of the ball diameter, can meet user requirements. Dashi, Shougang Mining Company iron ore concentrator 12 series, all Sec ball mill to switch to the quenching ball after 10 years of use than ordinary cast iron, hardened ball consumption is reduced by 13%; without heat treatment than ordinary cast iron ball (low ball), saving 35% to 40%, a promising mid-range ball. (3) high-grade iron ball. Refers to high-alloy iron ball, a typical representative of high-chrome ball 50 N120mm high-chrome ball usually hardness HRC = 58-62, n. Impact value in the 3.9 ~ 6.7 J / crnz. Microstructure: from the surface to the heart are fine acicular martensite + carbide. The salient features of the ball is a high hardness, high initial cost. Its cost effectiveness in the application of the cement industry is successful. Ferrous metallurgy mine concentrator should not be used. More for wet grinding of iron ore processing, high chrome balls between the friction coefficient is small (Table 5.3 -3, Table 5.3-4), sliding too much in the lower ball consumption while also reducing the mill processing capacity.

by: libby

POST COMMENT

How To Decrypt And Rip Dvd Act Of Valor On Mac The Vikings Are Coming, And Taking Over Costa Del Sol, Again A Taxi Ride And A Stranger Earn More And Spend Less With Seo Company Difference Between Second Mortgage And Home Equity Loan Every Single 1 Of The Text Facts, With Out Each And Every Of The Charges Kingfishers Packers And Movers And Their Services In Hyderabad Buy Properties In Spain With Utmost Ease And Comfort India Travel: Colorful, Exotic And Exquisite Summer Camp Activities Polishing Kids Talents And Enhancing Their Skills Hybrid Conferencing Converges Pstn And Voip Calls Seven Sentences Be Favored By Both Boys And Girls Pay Out The Golden Time Of holidays In Dubai And Get Pleasure From What You Have Seen