Ball mills use in all industries needs a material grinding. Steel grinding balls use as grinding media in such mills. In this article, we will consider the steel grinding balls use in coal grinding. Coal grinding is preparatory process to a creating mixture for combustion in boilers at thermal power plants. To a high-quality fuel creation for the TPP units furnaces (fuel has the coal basis), needs to achieve the maximum material grinding degree and maximally reduce the coal dust moisture content. Fuel drying and fuel grinding can be carried out separately or jointly in one unit. If these processes occur separately, then coal dried in drying drums and ground in short ball mills. The ratio of drum length to the drum diameter is usually 1.5: 1. The 40 mm grinding balls of the 2nd and the 3rd hardness groups have used for coal grinding at thermal power plants in USSR. This is due to a fairly low hardness indicator of the grinded material and absence the grinding balls with higher hardness groups, in the past. Following the coal grinding world practice, Energosteel company specialists among the first offered for customers to use grinding balls the 4-th and 5-th hardness groups for coal grinding. Numerous […]
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Let us consider another calculation of grinding balls assortment for the initial loading of a clinker ball mill. We have obtained all necessary data through the online service on our website. Note that this customer is not a resident of Ukraine and it was not possible to source the specifics of customer’s production. The customer specializes in cement production. The production parameters are as follows: The inner drum of the ball mill is divided into two chambers. The lining of the first chamber is steel slabs with elevators. The lining of the second chamber is rubber slabs of the type “wave”. Dry grinding method. Grinding material is a mixture of limestone (chalk, marble or other) in 75% and 25% clay. The size of the material is 13-15mm. Grinding requirement: residue on a sieve (size of 80μn) is not more than 7%. Since cement production material is sufficiently abrasive, it is necessary to use grinding balls with increased hardness. We have refined the material parameters of the armour platingin the first chamber and recommended to our client to use the balls with the volume hardness of at least 60 HRC. The coefficient of grinding for the mill is 22-25 per cent […]
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The calculation of the filling degree the ball mill with grinding media is a unique online service on our website. Recently our potential customers often use this service. We therefore decided to share with you the results of the calculation of the range of grinding ball assortment, which our specialists recommend on a case-by-case basis (request). Customer specialization is the production of various mixtures for construction works. Production parameters are as follows: Single-chamber ball mill 1400x7100mm. “Wave” lining plates Dry grinding method. Shredding material is slag (by-product or waste from metal production). The material size in the power of the ball mill is 1mm. Grinding requirement is the residue on a sieve (size of 80μn) not more than 5%. It is necessary to remember that the hardness of the lining plates should be 10-15% higher than the hardness of the grinding balls used. Filling rate of grinding balls for this mill is 25-27 per cent of the total internal volume, i.e. approximately 13-15 tons of grinding balls. The calculation of the average diameter of the grinding ball in the mill showed that it is necessary to use 23.74mm steel grinding balls for maximum effective grinding. Knowing that the loading rate […]
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The ball mill launching is one of the most complex technical processes in material grinding. The need for the method of the ball mill launching arises in two cases: “Start” of new production (expansion of existing plant); The ball mill launch after the preventive maintenance and/or emergency stop. The correct way to launch a ball mill after the preventive maintenance and/or emergency stop was discussed earlier in our publication. We recall that this methodology was developed in cooperation with the Belgorod State Technological University of Mr. V.G. Shukhov. This method has proven its effectiveness in practice. A lot of our clients “have adopted it” and use it constantly. We have faced with the task of launching a ball mill for new production recently. We will not disclose all information, just say that this enterprise is in Ukraine and it will declare itself on the building materials market in the near future. At the end of 2019, the technologist of new production approached us in order to help him to complete the ball mills with the necessary of grinding balls assortment. Based on the results of the completed questionnaire, we have proposed optimum grinding balls assortment, which will ensure maximum effective […]
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In the previous article, we talked about one of the steel structure investigation method (the fracture method) and its application in the steel grinding balls production. Today we will discuss the possibilities of using this method in production. The opportunity of using the fracture method consists in determining the correctness of rolling stand settings and as a result, in determining the product quality steel grinding balls. As it’s known, the steel structure after rolling has a certain texture. Rolling texture is a structure formed during hot plastic deformation, characterized by the elongation of the grains in the direction of deformation and the predominantly crystallographic orientation of the crystallites. The base billet for the production of steel grinding balls is a hot rolled round bar, produced by a longitudinal rolling method. The steel grinding balls are produced by the cross-rolling method, the texture is the meridians along the rolling axis. Based on this standard, it is possible not only to determine the depth of the tempered layer, but also to assess the correctness of rolling stand settings and make changes in the settings in time to avoid unnecessary internal voltage, defects of grinding ball structure and improve the product quality.
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The durability of steel grinding balls is determined not only by their hardness, but also by the quality of the steel macro and micro structure. The structure of the steel from which steel grinding balls are made is studied using the fracture method. This method consists in determining the steel structure by looking at its fracturing or a specially prepared surface (in the case of Energosteel -templets). This gives an idea of the general structure of the metal and the presence of defects therein. We would like to draw your attention to the fact that this method differs from fractography, because it does not apply magnifying instruments. Fracture method can be attributed to the first stage of fractographic analysis – visual examination. Fractography aims at determining the causes of the balls fracture, while fracture method used in our plant aims at improving the grinding balls quality, thus preventing splits during the use of grinding balls. What is a fractis? The fractis is the surface of the sample split when it breaks. In order to get the split of the steel grinding ball, the «Energosteel» plant uses an impact drop machine. But the destruction of our grinding balls is not so […]
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The issue of energy efficiency is one of the main one at any enterprise. The grinding process in the ball mill is highly energy intensive, because grinding process accounts for up to 45% of total energy consumption. It is not possible to estimate the power consumed by the mill drive without taking into account all the factors influencing the grinding process, such as the contact of grinding balls, their impact, the transfer of mechanical energy from one grinding ball to another, and then to the mill drum. Much research from classical theories to modern works is aimed at determining the power consumed by the drive of ball drum mills. The power absorbed by the drive can be divided into useful and harmful components which are spent on: the grinding of new material entering the mill; the lifting the steel grinding balls to a certain height; the lining and grinding balls wear; losses in mechanical transfer. The power consumed by the mill drive shall be calculated by the formula: where: Р0 – the power spent on rotating the mill drum and the output of the grinding load of the specified operating mode, kW; Рхх – the power expended to overcome friction […]
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The operating-mode selection of the ball mill (sometimes called “the operating-mode of grinding media”) depends on three main parameters: The relative frequency speed of drum is equal to the ratio between the actual speed to critical speed of mill drum. Proxy critical rotation frequency of rotation of the drum is equivalent to a speed at which the inertia of balls rotational motion equals the gravity of this ball. In so doing, grinding media of infinitesimal size raised to the highest point are in dynamic equilibrium. Critical speed is calculated by the formula: where: D – inside diameter of ball mill drum, m. Ratio of grinding mill loading by grinding balls. Ratio of grinding balls volume to mill working volume is calculated by the formula: where: Gн – mass of grinding balls, kg; γ – apparent density of grinding media, kg/m3; L – drum length, m. Apparent density of grinding media depends on ball diameter and density of the material. Technological parameters of grinding: grinded material, requirement for the grinding, etc. The mill operation modes are as follows: The ”cascade” – the rolling the grinding balls inside the mill drum. Mixed mode – the rolling the grinding balls when part of […]
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On September 2, within the walls of Energosteel Company, the executive director of the Canadian-Ukrainian Association, Emma Turos, met with representatives of Energosteel, a manufacturer of steel grinding balls. At the meeting, both sides discussed the possibility of meeting and negotiating with Canadian customers and representatives of local municipalities, ways to finance the Canadian-Ukrainian project to supply steel grinding balls to Canada, and set priorities in working with the new region. Following the meeting, a plan for further development and cooperation of the company with Canadian partners was outlined.
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According to DSTU 8538:2015, grinding balls 50 HRC after heat treatment should be consistent with the standards shown in table 2 (DSTU 8538:2015), for example, for grinding balls with a nominal diameter of 120 mm, this is at least 50 HRC / 477 HB on the surface. Please note that information about the upper rate is not specified. The main standards for measuring steel grinding balls 50 HRC, according to the control methods prescribed in DSTU 8538:2015, is to determine only the hardness on the surface on two diametrically opposite sites. Thus, when production and supply of grinding balls 50 HRC, the testing Energosteel’s laboratory takes measurements only on the balls surface in accordance with the DSTU 8538:2015 standards. However, if the surface of produced grinding balls exceeds the minimum permissible values this does not mean that grinding balls quality does not comply with DSTU 8538:2015, because the upper limit of the norm is not regulated.
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As we have mentioned repeatedly in our articles, the right choose of lining plate is very important. 10-15 years ago there was only one main purpose of lining plates was protection of the mill hull from mechanical damage. To date, the design of the lining plates is based on the need to form a grinding line, which will ensure the maximum efficiency of the grinding process by steel grinding balls. Lining plates differ in size, material and method of attachment to the mill casing and the shape of surface. According to the type of profile, lining plates can be smooth, stepped wavy, combined, corrugated, cellular, heeled and other. Lining plate’s durability and the lift height of steel grinding balls depend on the geometric shape of the lining plate surface. When designing new types of liners one of the objectives is the reduction in slipping of grinding balls and grinded material over the lining surface, which improves the grinding quality and, as a result, increases mill productivity. Ring lining plates are more durable than liners with smooth and wave working surface. This is because the liners projections get stronger under the impact of the steel grinding balls. Figure 1 below shows […]
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Many companies are asking themselves: what is the need for ISO 9001? ISO 9001 certification of quality management systems helps businesses to develop and improve efficiency, as well as commitment to quality. For “Energosteel” the notion of quality means the ability to meet the expectations and needs of our customers on an ongoing basis and to be flexible to changes in these needs. So, Energosteel Plant LLC successfully passed the audit of certified quality management system in the production of steel grinding balls for compliance with ISO 9001:2015, at the end of July 2020. Audit was conducted by state enterprise “Kharkiv Regional Research and Production Center for Standardization, Metrology and Certification”. Energosteel Plant LLC confirmed the validity of the certificate without any comments and obtained a new certificate No. UA 8О072.33671383.1-2020 dated 03.08.2020 with a changed legal address. Working in accordance with ISO 9001 standards, Energosteel Plant LLC stands out on the market, because effective quality management allows us to meet the needs of our customers as efficiently as possible, to use time and money resources more productively, raise staff motivation and engagement to a new level, improving internal processes, to meet the requirements of foreign partners and to provide […]
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The widespread view that the oxidation process has a significant impact on the grinding balls consumption when wet grinding at the mining and processing plants recently. Cast grinding media producers use this argument often. We will try to look into the matter. Of course, oxidation process of grinding balls, especially steel grinding balls when wet grinding (free of corrosion resistant chemical additives) might be the case. Mainly, this is determined by water pH rate, used in the enterprise. The steel and cast iron chemical composition is most often introduced chromium, nickel, aluminium and silicon to minimize the corrosion process. The existence of these chemical elements in sufficient quantities provides steel and cast iron water-resistant in wet environments, in solutions of many acids and alkalis and in the dry gases at high temperatures. When the carbon content is high, the erosion resistance of steels increases. However, in some cases, the erosion proof is high when carbon content is low and the existence of the alloying elements. We use in our production just such a manganese, nickel and chrome doped steel. Grinding bodies’ corrosion so small that it does not actually affect the total grinding media depreciation in the ball mill. According […]
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Recently, Company Energosteel Ltd, a Ukrainian manufacturer of steel grinding balls, joined the The Canada-Ukraine Trade and Investment Support Project (CUTIS). In partnership with Ministry of economic development and Export Promotion Office this project will provide Ukrainian businesses with the information needed to export their goods to Canada and attract Canadian investments to Ukraine. From now on, Company Energosteel Ltd will not only be able to assert itself more confidently on the Canadian market of grinding ball consumers, but will also receive strong support during participation in trade fairs, exhibitions and B2B events aimed at expanding business connections with Canada, increasing export and attracting investment.
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Each producer that uses grinding in its production faced the situation when specific grinding media consumption exceeds the previously established norm. Generally, in the view of the consumers the single reason is the quality change of grinding balls used. Practice shows that in more than 80% of cases the change in the technological basis causes the increase of the grinding media consumption. These changes may be invisible to the employees of the production plant at first sight. Only a thorough analysis of grinding technology will help to understand the reasons for this situation. For years of experience in the grinding media market, we have compiled for you several main factors (reasons), which can affect the change of grinding balls consumption. Modifying the physico-chemical properties of grinding material. Changes to mill performance. Yes, such things do happen. Maintenance or upgrading of material supply conveyor can affect the speed and quantity of material loading to the ball mill. In the wet grinding, changing the flush density of the ball mill can significantly affect the grinding balls consumption. Everyone knows that for prevention not fully grinded material it is necessary either to load the grinding balls into the mill or to reduce the […]
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We announced the launch of an online service on our website recently. It helps customers accurately calculate the mass of grinding media in the mill. We received more than a dozen requests from our customers who took advantage of this service in a month. It may be noted, that the service is designed exclusively to determine the grinding balls mass of in a ball mill. We focus on this, because at the same time we received many requests, the purpose of which was the assistance in determining the grinding ball range when loading the mill from scratch. The difficulty of this calculation is to determine the average diameter of grinding balls in assembly, at which the required grinding quality will be achieved as soon as possible. As you know, there are two ways to determine the average diameter of the grinding media in the mill: the mathematical method and the selecting grinding media from the mill. We have already considered both calculation options in our publications. Specialists of «Energosteel» Company are always ready to help you to form and deliver the necessary assembly of grinding balls, which will reveal as much as possible the efficiency of grinding process at your […]
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The crushed sand is used in aerated concrete producing. The gypsum, cement and other additives are added to sand for the strength of the mixture. Sand is crushed in the ball mills, the type of grinding is wet ball milling. The steel grinding balls 25-40 mm in diameter are in the mill. Each manufacturer has its own milling requirements. On average, these requirements tend to the 15-18% of the sieve residue (8 microns). After grinding, the resulting mixture enters the hopper, in which it is constantly mixed using a “mixer”. The resulting solution is stirred until the homogeneous wet concrete is obtained. After that, foam is added to the industrial “mixer” where the solution was mixed. The concrete solution mixed with foam further is poured into molds. The foam concrete is conditioned for 4 hours after pouring. During this time, the process of initial capture occurs. Then the blocks are loaded onto pallets and transported for further drying. Energosteel company produces high-quality steel grinding balls optimally suiting for grinding quartzite (sand). To date, our customers include more than 25 companies that specialize in the production of aerated concrete blocks both in Ukraine and in the near abroad.
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In January this year, we launched a new service on our website. Therefore, for those of you who don’t know it yet, we recall that this service is intended for calculation of the filling degree the ball mill with grinding media. You will receive accurate calculation of the filling degree the ball mill with grinding media at the following link and by filling in the proper fields as quickly as possible. Our clients and customers of steel grinding balls provide feedback on the use of this service. According to the customers, this calculation allows: to determine correctly and quickly the amount of grinding media needed for loading the ball mill; significant savings of time for calculation of the filling degree the ball mill; to avoid the production stoppages. Based on the advantages of this service, it can be concluded that the main one is the reduction in the number of production stoppages, i.e. the saving of time. As we know, time is money. What about you? Have you already use this service? No? It’s time for the following link and to receive the important information for your production.
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For a month, we have been considering various methods for determining the energy indexes of material destruction. Common to all these tests under consideration is that all of them are based on the use of the third Bond theory. Despite the fact that this theory was proposed as early as the 1950s, its basic postulates are applied to date. All reviewed methods have been developed and tested by foreign specialized institutes. They are widely used throughout the world, including Ukraine and the countries of the Near Abroad. Currently, the development of new deposits is not as common as it was in the early 20th century. In most cases, these methods are used in the production expansion. When providing technical customer support, the specialists of the Energosteel Company also use some methods that allow optimally selecting and recommending the necessary grinding media to increase the grinding efficiency. Notably, the domestic Mechanobr Research Institute has developed several methods for determining the energy indexes of material destruction. We will try to consider them in our publications in near future. Follow the news on the Energosteel site!
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