Research of the Process of Production of Steel Square Continuous Billets for Rolling Balls of Large Diameter

The paper investigates the technology of production of steel billets continuously cast billets for rolling balls of large diameter. In Kazakhstan, in connection with the development of new copper deposits such as Aktogay and Bozshakol, the need for large diameter steel grinding balls for primary ore processing has increased. The main problem in the operation of large diameter grinding balls is the tendency of the grinding media to break during operation. The authors of the work investigated the process of production of steel billets continuously cast billets with a cross section of 150 × 150 mm for rolling balls of large diameter (d 125 mm) in the PB LLP "KSP Steel", which showed that the breaking of grinding balls is initiated mainly by the presence of internal discontinuities (gas axial looseness) in continuously cast billets. Studies have shown that the technological scheme for the production of grinding balls with a diameter of 125 mm from continuously cast billets with a section of 150 × 150 mm, including steel smelting in an arc furnace with steel finishing on a ladle-furnace unit, deoxidation with aluminum and degassing in a ladle vacuum apparatus, casting steel in a closed jet on a continuous casting and further production of rolled stock on a rough rolling mill ensures the absence of internal discontinuities (gas bubbles, axial looseness) in the workpieces and ensures the production of high quality balls.

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Development and mastering of technologies of production at PJSC MMK a new generation steel rolled stock for m a in pipelines

Ferrous Metallurgy Bulletin of Scientific Technical and Economic Information ◽

10.32339/0135-5910-2021-7-791-803 ◽

2021 ◽

Vol 77 (7) ◽

pp. 791-803

Author(s):

P. V. Shilyaev ◽

S. V. Denisov ◽

P. A. Stekanov ◽

O. V. Sych ◽

E. I. Khlusova ◽

...

Keyword(s):

Oil And Gas ◽

Large Diameter ◽

Accelerated Cooling ◽

Rolled Stock ◽

Chemical Compositions ◽

Subgrain Structure ◽

Pipe Steels ◽

Plastic Properties ◽

Wide Range ◽

New Generation

In view of arising needs of Russian oil and gas sectors, elaboration and implementation into series production competitive pipe products became an actual task for domestic enterprises of metallurgical industry. Generalized results of elaboration of chemical compositions and automated technologies of sheet rolled stock of new generation production from low-alloyed pipe steels of various strength classes at PJSC MMK presented. It was shown that the selected chemical compositions ensure forming finedispersed ferrite-bainite structure with bainite of granular morphology in a wide range of cooling rates. The elaborated technological modes of sheet rolled stock production from pipe steels stipulate for elimination considerable growth of austenite grain at heating before the rolling, refinement of austenite grains due to recrystallization processes, forming of extensive subgrain structure of austenite at plastic deformation, forming disperse structures during phase transformation in the process of controlled accelerated cooling; forming of extensive fragmented structure in а-phase. The level of strength, tough-plastic properties and resistance against brittle destruction (based on results of tests with a falling weight with determination of tough component share in the break of full-thickness samples) of sheet rolled stock of pipe steels with various chemical composition of PJSC MMK production was demonstrated. Results of study of tests the sheet rolled stock of high-strength steels for pipes of large diameter presented. Objects of the elaborated pipe steels implementation indicated.

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Research and Development Into Low Temperature Toughness of Large Diameter Heavy Wall X80 Pipeline Steel at Shougang Steel

Volume 3: Materials and Joining ◽

10.1115/ipc2012-90326 ◽

2012 ◽

Cited By ~ 2

Author(s):

Wenhua Ding ◽

Zhonghang Jiang ◽

Jiading Li ◽

Shaopo Li ◽

Chunhe Zha ◽

...

Keyword(s):

Low Temperature ◽

Research And Development ◽

Oil And Gas ◽

Volume Fraction ◽

Pipeline Steel ◽

Large Diameter ◽

X80 Pipeline Steel ◽

Low Temperature Toughness ◽

Process Strategy ◽

Rough Rolling

In recent years the trend in oil and gas transmission pipelines has been toward higher operating pressures. This trend, while the desire to keep steel costs low, has resulted in an increased demand for large diameter heavy wall X80 with good low temperature toughness. It is well known that improving the low temperature toughness with increasing wall thickness of the pipeline is very difficult. To overcome the difficulty of producing consistent low temperature toughness in heavy wall pipe Shougang Steel Research in cooperation with the Shougang Steel Qinhuangdao China (Shouqin) 4.3 m heavy wide plate mill research was conducted. This paper describes the background, composition design and process strategy to produce good low temperature toughness in heavy wall API plate. The importance of the slab reheating schedule and recrystallized rolling process/schedule that occurs during the roughing process will be discussed. The effect of per pass reductions and work roll speed rotation on the strain introduced was analyzed by means of the numerical simulation technology. Furthermore, the center thickness microstructure and low temperature toughness of plate under the different rolling schedules were researched. The results showed a low reheating temperature and slow rough rolling speed should be implemented. The per pass reductions during recrystallized rough rolling should be increased in a steady fashion, with special emphasis on the reduction of the final roughing pass prior to the intermediate hold (transfer thickness for finishing). When the final roughing pass had a per pass reduction of more than 15%, the main microstructure of plate consists of uniform (surface to center) fine ferrite/acicular ferrite with a small volume fraction of M-A constituent. This fine uniform microstructure results in good low temperature fracture toughness in heavier plate thicknesses. Results of this research and development work will be discussed.

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Introduction of Three-Stage Thermal Hardening Technology for Large Diameter Grinding Balls

Metallurgist ◽

10.1007/s11015-014-9812-7 ◽

2014 ◽

Vol 57 (9-10) ◽

pp. 849-854 ◽

Cited By ~ 3

Author(s):

V. G. Efremenko ◽

E. S. Popov ◽

S. O. Kuz’min ◽

O. I. Trufanova ◽

A. V. Efremenko

Keyword(s):

Large Diameter ◽

Thermal Hardening ◽

Grinding Balls

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Features of the expansion process in the technology of production of large diameter pipes for main oil and gas pipelines

Metal and Casting of Ukraine ◽

10.15407/steelcast2021.03.087 ◽

2021 ◽

Vol 29 (3) ◽

pp. 87-93

Author(s):

V.V. Protsiv ◽

◽

V.U. Hryhorenko ◽

Keyword(s):

Oil And Gas ◽

Large Diameter ◽

Gas Pipelines ◽

Expansion Process ◽

Oil And Gas Pipelines ◽

Large Diameter Pipes ◽

Technology Of Production

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Preparation Sericite Nanoflakes by Exfoliation of Wet Ultrafine Grinding

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.178.242 ◽

2010 ◽

Vol 178 ◽

pp. 242-247 ◽

Cited By ~ 2

Author(s):

Hao Ding ◽

Xia Xu ◽

Ning Liang ◽

Yue Bo Wang

Keyword(s):

Shear Stress ◽

Solid Content ◽

Diameter Ratio ◽

Mass Ratio ◽

Optimum Conditions ◽

Grinding Balls ◽

Grinding Media ◽

Ultrafine Grinding ◽

Ultraviolet Ray ◽

Grinding Time

Sericite nanoflakes were prepared by exfoliating sericite layers by wet ultrafine grinding. Their appearance morphologies and main properties were characterized. Optimum conditions were studied with the purpose of forming shear stress which was beneficial to the exfoliation of mineral flakes. The results indicated that sericite nanoflakes could be prepared. Mass ratio of grinding media to materials, diameter ratio of grinding balls, solid content of powders and grinding time had significant effects on the preparation. The thicknesses of sericite nanoflakes were 20-80 nm, and the transmittances of ultraviolet ray with wavelength of 190-220 nm were only 0.1%-1%. This demonstrated that sericite nanoflakes had the function of shielding ultraviolet ray.

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Development of a digital SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010008609x ◽

1991 ◽

Vol 49 ◽

pp. 358-359

Author(s):

A. Yamada ◽

A. Shibano ◽

K. Harasawa ◽

T. Kobayashi ◽

H. Fukuda ◽

...

Keyword(s):

Large Diameter ◽

Objective Lens ◽

Large Specimen ◽

Backscattered Electrons ◽

Digital Scanning ◽

Junction Type ◽

High Resolution Images ◽

Working Distance ◽

Type Detector ◽

Short Working

A newly developed digital scanning electron microscope, the JSM-6300, has the following features: Equipped with a narrower conical objective lens (OL), it allows high resolution images to be obtained easily at a short working distance (WD) and a large specimen tilt angle. In addition, it is provided with automatic functions and digital image processing functions for ease of operation.Conical C-F lens: The newly developed conical C-F objective lens, having low aberration characteristics over a wide WD range, allows a large-diameter (3-inch) specimen to be tilted up to 60° at short WD, and provides images with low magnifications starting at 10*. On the bottom of the lens, a p n junction type detector is provided to detect backscattered electrons (BE) from the specimen. As the narrower conical 0L increases the secondary electron (SE) detector's field intensity on the specimen surface, high SE image quality is obtained.

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