scholarly journals Influence of structure of burned pellets on strength and destruction in static compression tests

2021 ◽  
Vol 64 (11) ◽  
pp. 785-792
Author(s):  
A. N. Dmitriev ◽  
V. G. Smirnova ◽  
E. A. Vyaznikova ◽  
A. V. Dolmatov ◽  
G. Yu. Vit'kina
Keyword(s):  
Compressive Strength ◽  
Iron Ore ◽  
Relative Size ◽  
Maximum Level ◽  
Compression Tests ◽  
Static Compression ◽  
Russian State Standard ◽  
Russian State ◽  
Iron Ore Pellet

The burned pellets must retain the strength from the time they come off the roasting machine until they are loaded into the blast furnace. One indicator of the strength of burned pellets is the compressive strength, i.e., the maximum applied load at which the iron-ore pellet completely collapses. The paper studies the character of destruction of burned iron-ore titanomagnetite pellets of fraction 10 - 16 mm in the static compression test according to the Russian State Standard 24765-81. It is shown that the main type of destruction during the test is the emergence and development of plane cracks passing through the center of the magnetite core, where the maximum radial tensile stresses act or in the immediate vicinity. In some cases, the trajectory of one of the destructive cracks deviates from the above plane and envelopes the magnetite core. Obviously, this is due to the presence of a second area of tensile stress concentration at the boundary of the magnetite core and the hematite shell, formed during cooling of the pellets, due to differences in their mechanical and thermophysical properties. As a result, the final structure of pellets is characterized by the presence of two zones -peripheral hematite and central magnetite. The role of the relative size of the magnetite core on the compressive strength of burned pellets has been determined. It was established that the strength characteristics of the pellet increase with a decrease in relative size of the magnetite core. During the process of magnetite complete oxidation (when the whole volume of the pellet consists of hematite), the maximum level of the pellets compressive strength can be: the maximum destructive force - 3300 N, destructive energy - 0.55 J, mass destructive energy - 0.18 J/g.

Role of MgO and Its Different Minerals on Properties of Iron Ore Pellet

2015 ◽  
Vol 69 (6) ◽  
pp. 1141-1153 ◽  
Author(s):  
Md. Meraj ◽  
Susanta Pramanik ◽  
Jagannath Pal
Keyword(s):  
Iron Ore ◽  
Iron Ore Pellet

Crashworthiness of cardboard panels reinforced with braided glass fiber rods for vehicle side impact protection

2018 ◽  
Vol 37 (23) ◽  
pp. 1387-1401 ◽  
Author(s):  
Gabriel Y Fortin ◽  
Elsayed A Elbadry ◽  
Hiroyuki Hamada
Keyword(s):  
Glass Fiber ◽  
Single Layer ◽  
Side Impact ◽  
Compression Tests ◽  
Static Compression ◽  
Compression Properties ◽  
Layer Orientation ◽  
Fiber Fragmentation ◽  
Crushing Behavior

This paper investigates the quasi-static compression properties of cardboard panels reinforced with braided glass fiber rods manufactured using a tubular braiding method. Compression tests are performed on single- and two-layer panels reinforced with varying number of rods and panel layer orientation. The crushing results of single-layer panels show more progressive crushing behavior than those of two-layer panels for different number of rods. In two-layer panels, certain rods are inclined from the direction of applied load due to deformation of the surrounding cardboard, resulting in reduced specific energy absorption compared with single-layer panels. Moreover, panels consisting of two layers of cardboard oriented in the same direction perform better than when the layers are off-set 90° where cardboard shifting is more pronounced. The role of cardboard is to constrain the rods from excessive splaying, causing greater levels of fiber fragmentation which consumes more energy compared with rods without cardboard.

Metallurgical properties of iron ore pellet when using lime powder instead of bentonite

2021 ◽  
Vol 97 ◽  
Author(s):  
Hien Tran Thi Thu ◽  
◽  
Kien Nguyen Ngoc ◽  
Yen Nguyen Duc
Keyword(s):  
Compressive Strength ◽  
Iron Ore ◽  
Holding Time ◽  
Degree Of Reduction ◽  
Metallurgical Properties ◽  
Green Strength ◽  
Different Temperatures ◽  
Iron Ore Pellet ◽  
Lime Powder ◽  
Bentonite Binder

This paper reported effects of lime powder and bentonite binder using in iron ore pelletization on metallurgical properties of pellets as green strength, compressive strength and degree of reduction. The investigated pellets contain 0, 1 and 2 mass % of lime powder and 2, 1 and 0 mass % of bentonite, respectively. Green balls were dried (105 °c for 24 hours) then heated at 1200 °c for 30 minutes. The reductibility of fired pellets was examined at different temperatures of 900, 1000 and 1100 °c with various holding time (45, 90 and 120 minutes). The results showed that the combination of 1 mass % of bentonite and 1 mass % of lime powder in the pellet gave the most apropriate metallurgical properties of pellets as green strength, porosity and degree of reduction. This material charging ratio can be recommended for application in manufacturing of the pellet.

Analysis of the Influence of the Degree of Reduction of Iron Ore Materials on the Shape and Location of the Cohesion Zone in a Blast Furnace

2021 ◽  
Vol 413 ◽  
pp. 157-166
Author(s):  
Andrey N. Dmitriev ◽  
Galina Yu. Vitkina ◽  
Roman V. Alektorov
Keyword(s):  
Blast Furnace ◽  
Iron Ore ◽  
Physical Modelling ◽  
Degree Of Reduction ◽  
Cohesion Zone ◽  
Reduction Of Iron ◽  
Russian State Standard ◽  
Russian State ◽  
Softening Process ◽  
Theoretical Foundations

The paper considers the theoretical foundations of softening of iron ore materials in a blast furnace (the so-called ‘cohesion zone’). The dependences of the temperature range of softening of iron ore materials (the temperatures of the beginning and ending of softening) on the degree of reduction are calculated and experimentally obtained. Physical modelling of the softening process of reduced iron ore materials was carried out using the Russian State Standard No 26517-85. The results of calculations of the location and shape of the cohesion zone in the blast furnace for iron ore materials with different metallurgical characteristics are presented.

THE TSARIST IRON WORKS IN RUSSIA IN THE 17TH CENTURY

2021 ◽  
Vol 7 (3) ◽  
pp. 103-116
Author(s):  
Larisa Yu. VАRENTSOVA
Keyword(s):  
Iron Ore ◽  
Manufacturing Industry ◽  
17Th Century ◽  
International Markets ◽  
Royal Family ◽  
Historical Science ◽  
Industrial Facilities ◽  
European Experience ◽  
Russian State

The palace manufacturing industry in Russia in the 17th century was represented by glass, morocco, linen, iron-making manufactories. They used the most advanced European technologies. Manufactories developed due to the exploitation of the population of the royal fiefdoms, soldiers, archers, domestic and foreign employees. Most of the products were intended for the needs of the royal family, a smaller one portion was used as sovereign grants and was bought up by the first-class nobility of Russia. A certain number of finished products were supplied to the domestic and international markets. The products of the palace iron works were exported abroad. At the same time, the organization of their activities in historical science remains virtually unexplored. The novelty of this article lies in the formulation of a scientific problem. Here is the list of points that were covered in our research. The role of the tsarist iron works in the economy of the tsarist domain in Russia in the 17th century is determined. The main types of products of the palace iron-making manufactories are identified. The features of their functioning are studied. The article analyzes the conditions under which Dutch entrepreneurs rented tsarist iron works in the Russian state in the 17th century. Methods of providing industrial facilities with labor are shown. The significance of the Ministry of Secret Affairs in the organization of iron ore mining, which was in charge of the royal iron works, is determined. Their historical and geographical coordinates are indicated. The features of sales of finished products are covered. The evolution of the tsarist iron-making industry in Russia during the 17th century is explained. In the palace fiefdoms, natural and human resources were used as much as possible. In the 17th century, in five districts of Russia (Maloyaroslavsky, Obolensky, Tula, Kashirsky, Moscow), the tsarist iron factories functioned. On which they used European experience in the use of production processes. Foreign specialists and entrepreneurs were invited to Russia. Dutch merchants A. Vinius, E. Vickens, P. Marselis, F. Akema, R. Adrian received a monopoly on the extraction of iron ore, the establishment of factories on unpopulated palace lands.

Mechanical Characteristics of Pavers with Iron Ore Tailings

2017 ◽  
Vol 864 ◽  
pp. 330-335
Author(s):  
J.N.R. Mantilla ◽  
Diego N. Miranda ◽  
Jamile Salim Fuina ◽  
E.V.M. Carrasco
Keyword(s):  
Compressive Strength ◽  
Modulus Of Elasticity ◽  
Iron Ore ◽  
Compression Tests ◽  
Natural Sand ◽  
Static Modulus ◽  
Concrete Mixtures ◽  
Iron Ore Tailings ◽  
Simple Compression ◽  
Static Modulus Of Elasticity

The objective of this study is to evaluate experimentally the mechanical compressive strength and static modulus of elasticity of concrete pavers for floors made with iron ore tailings as aggregate concrete. Pavers were manufactured with four different concrete mixtures (cement, natural sand, industrial sand, iron ore tailings, crushed stone), and performed simple compression tests to determine the compressive strength and modulus of elasticity. The pavers manufactured with those concrete mixtures showed greater strength specified by the Brazilian standard. It was possible to find a correlation between modulus of elasticity and compressive strength.

scholarly journals Compressive Behavior of Aluminum Microfibers Reinforced Semi-Rigid Polyurethane Foams

Polymers ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1298 ◽  
Author(s):  
Emanoil Linul ◽  
Cristina Vălean ◽  
Petrică-Andrei Linul
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Energy Absorption ◽  
Physical And Mechanical Properties ◽  
Strength Properties ◽  
Polyurethane Foams ◽  
Compression Tests ◽  
Compressive Behavior ◽  
Static Compression ◽  
Pu Foams

Unreinforced and reinforced semi-rigid polyurethane (PU) foams were prepared and their compressive behavior was investigated. Aluminum microfibers (AMs) were added to the formulations to investigate their effect on mechanical properties and crush performances of closed-cell semi-rigid PU foams. Physical and mechanical properties of foams, including foam density, quasi-elastic gradient, compressive strength, densification strain, and energy absorption capability, were determined. The quasi-static compression tests were carried out at room temperature on cubic samples with a loading speed of 10 mm/min. Experimental results showed that the elastic properties and compressive strengths of reinforced semi-rigid PU foams were increased by addition of AMs into the foams. This increase in properties (61.81%-compressive strength and 71.29%-energy absorption) was obtained by adding up to 1.5% (of the foam liquid mass) aluminum microfibers. Above this upper limit of 1.5% AMs (e.g., 2% AMs), the compressive behavior changes and the energy absorption increases only by 12.68%; while the strength properties decreases by about 14.58% compared to unreinforced semi-rigid PU foam. The energy absorption performances of AMs reinforced semi-rigid PU foams were also found to be dependent on the percentage of microfiber in the same manner as the elastic and strength properties.

scholarly journals The study of pelletizing of mixed hematite and magnetite ores

2019 ◽  
Vol 51 (1) ◽  
pp. 27-38 ◽  
Author(s):  
P.S. Kumar ◽  
B.P. Ravi ◽  
O. Sivrikaya ◽  
R.K. Nanda
Keyword(s):  
Compressive Strength ◽  
Blast Furnace ◽  
Iron Ore ◽  
Mixing Ratios ◽  
Pellet Production ◽  
Strength Tests ◽  
Iron Ore Pellet ◽  
Drop Number ◽  
Mechanical Strengths ◽  
Pellet Feed

The present study aims to investigate the use of mixed hematite and magnetite ores in iron ore pellet production. Pelletizing tests were carried out on the hematite and magnetite premixed pellet feed. Drop number and compressive strength tests for green and dry pellets; porosity, compressive strength and reducibility tests for fired pellets were carried out to determine the influence of mixing ratios of both iron oxides on those pellet properties. Experimental results showed that as the hematite content in the mix pellets is increased, the green drop number decreased from 6.5 to 5.2, the green compressive strength decreased from 1.51 to 1.28 kg/pellet and the dry compressive strength decreased from 2.50 to 1.60 kg/pellet. It was determined that fired compressive strength of mix pellets decreased from 380 to 230 kg/pellet when the hematite content in the mixed pellet is increased. The reducibility of mix pellets had almost the same trend and it was faster up to 40 min reduction time. The results showed that the use of hematite together with magnetite is possible to produce pellets with sufficiently good quality in terms of wet, dry and fired mechanical strengths. The porosity and reducibility values of mix pellets were also found to be adequate to use as feed for the blast furnace.

MODELLING AND CONTROLLING THE ENTERPRISE RISKS COMPLEX ASSESSMENT SYSTEMON THE BASIS OF RUSSIAN STATE STANDARD ISO 9001-2015 CONCERNING RISK-ORIENTED THINKING. GENERAL PROBLEMS AND WAYS OF SOLVING THEM

2020 ◽  
Vol 2020 (2) ◽  
pp. 33-41
Author(s):  
Irina Merzlyakova ◽  
Aleksandr Feofanov
Keyword(s):  
Risk Assessment ◽  
Risk Management ◽  
State Standard ◽  
Control Model ◽  
Enterprise Risk Management ◽  
Iso 9001 ◽  
Management Procedure ◽  
Russian State Standard ◽  
Russian State ◽  
Enterprise Risk

The article considers general problems of implementing the enterprise risk management procedure. One of the ways to solve the problems arising when meeting Russian state standard ISO 9001-2015 requirements concerning risk-oriented thinking is presented. A risk assessment control model aimed at coordinating all kinds of the enterprise departments activities, forming a clear algorithm of risk management procedure implementation and attracting a greater number of employees towards this activity is offered.

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