Design of a roll crusher for sunflower stems and substantiation of the rational modes of its operation

This paper reports a study of the technological process of grinding plant residues of sunflower and the causal relationships of factors that form the system of quality indicators. The necessary prerequisites for determining rational modes and parameters of the roll crusher have been devised. A prototype of the roll crusher was designed and fabricated, in which the cutting knives are arranged along the entire width of the grip in a staggered manner, with the possibility to change the angle of inclination to the axis of drum rotation in the range of 5...20°. It was established that in the case of the right-side arrangement of the cutting edge of knives, the highest total level of the percentage of crushed stems in the range of 101‒150 mm with an additional load weighing 800 kg exceeded by 1.58 times the corresponding indicators of the roll with an additional load of 600 kg. The largest overall value of the percentage of crushed stems in the range of 0‒200 mm when additionally loading the roll with 800 kg was 1.13 times higher than the corresponding indicators of the roll with an additional load of 600 kg. In the range of 0‒200 mm, with an additional load on the roll of 600 kg, at the left-side arrangement of the cutting edge of the knives of the roll, higher total percentage of crushed stems was observed compared to the right-side arrangement. At a speed of 7.45 km/h, 13.6 km/h, the cumulative value of the percentage of crushed stems exceeded the corresponding indicators at the right-side arrangement of knives by 1.09 times, at the speed of 18.6 km/h – by 1.04 times, at the speed of 22 km/h – by 1.04 times, respectively. It has been noted that at the left-side arrangement of the cutting edge of the knives of the roll, the percentage of crushed stems in the range of 51‒100 mm, with an additional load of 600 kg, exceeded the corresponding indicators with an additional load of 800 kg. At the speed of 10.08 km/h, it was exceeded by 1.9 times; at the speed of 13.6 km/h – by 1.44 times; at the speed of 18.6 km/h – by 1.96 times; at the speed of 22 km/h – by 1.99 times, respectively

Efficient Crushing of Malt in Small Enterprises

Современные малые пивоваренные предприятия имеют более простое аппаратурное оснащение по сравнению с большими. Поэтому выход готовой продукции меньше, а затраты на единицу продукции выше. Важная для производства сусла стадия дробления солода и другого зернового сырья осуществляется, как правило, на 2-валковых солододробилках. Цель работы - дать сравнительный анализ различных способов дробления солода и рассмотреть возможность применения 4-валковой дробилки вместо 2-валковой на предприятии малой производительности. Проведен сравнительный анализ сусла, полученного из одной партии солода, измельченного на 2-валковой и 4-валковой дробилках. Использованы традиционные для пивоварения методы анализов. Показатели сусла, полученного из солода после дробления на 4-валковой дробилке, лучше по технологически значимым показателям: выше содержание экстракта в сусле, его степень сбраживания, диастатическая сила, стойкость пива; ниже продолжительность осахаривания, вязкость и цветность сусла. Замена 2-валковой солододробилки на 4-валковую позволит повысить выход продукта более высоких качества и потребительских свойств из единицы сырья. Modern small breweries have simpler equipment compared to large ones. Therefore, the output of finished products is less, and unit costs are higher. The stage of crushing malt and other grain raw materials, which is important for the production of wort, is carried out, as a rule, on two-roll malt grinders. The purpose of the work is to give a comparative analysis of various methods of crushing malt and to consider the possibility of using a four-roll crusher instead of a two-roll one at a low-productivity enterprise. The analysis of wort obtained from one batch of malt crushed on two-roll and four-roll crushers was carried out. Traditional methods of analysis for brewing were used. The indicators of the wort obtained from malt after crushing on a four-roll crusher are better in terms of technologically significant indicators: the extract content in the wort is higher, its degree of fermentation, diastatic strength, beer durability; the duration of saccharification, viscosity and color are lower.

ANALYSIS OF THE WAYS OF GRINDING OF BEAN CULTURES SEEDS

Рассмотрены способы измельчения семян люпина и эспарцета на существующем в кондитерском производстве оборудовании – дезинтеграторе, валковой дробилке и трехвалковой мельнице с целью повышения эффективности дробления семян бобовых культур и, как следствие, их биологической ценности после дезинтегральной обработки. Установлено, что с увеличением зазора между валками возрастает среднее значение размеров дробленых частиц, т. е. доля крупных фракций увеличивается, мелких – снижается, при этом дисперсия существенно не меняется. При использовании валковой дробилки, варьируя величину зазора между валками и частоту вращения, можно оптимизировать режим дробления. Доказано, что применение для дробления семян вертикальной трехвалковой мельницы с засыпанными в нее вместе с семенами бобовых культур металлическими твердосплавными шарами за счет комбинаций ударных и истирающих воздействий на частицы семян интенсифицирует процесс, снижает время помола и способствует получению равномерного гранулометрического состава, обеспечивая высокий эффект измельчения сырья с сохранением его качественных показателей. The ways of grinding of seeds lupine and cock's head on the existing in the confectionery industry equipment, disintegrator, roller crusher and three-roll mill with the purpose of increase of efficiency of the grinding bean cultures seeds and, consequently, their biological value after disintegrating treatment were considered. It is established that with increase in gap between the rolls, the average value of the sizes of crushed particles increase, i.e. the share of large fractions increases, small – decreases, this variance does not change significantly. When using roll crusher, by varying the size of the gap between the rolls and the rotational speed can optimize the crushing mode. It is proved that use for crushing seeds vertical three-roll mill with filled in it along with the seeds of legumes metal carbide balls due to the combinations of impact and abrasive effects on the particles of seed intensifies process reduces grind time and helps to ensure a uniform particle size distribution, providing a high effect grinding of raw materials while maintaining its quality.

FUNDAMENTALS OF THE LUMP CRUSHING THEORY. WORKING PROCESSES OF CRUSHING AND SCREENING EQUIPMENT. LECTURE 8

The article presents materials of Lecture 8 in Theory of carrying and lifting, construction and road vehicles and equipment, which describes the following issues: the rock properties, the rock crushing degree, the basics of the lump crushing theory and types of crushing machines. The technological process of crushing with a roll crusher is described; the values of forces acting in roll crushers are calculated.Along with the process of crushing, the article deals with the processes of segregation and concentration, the basic of the screening (fractionation) theory and features of the hydraulic classification of nonmetallic materials.

Experimental study of fractional composition of pieces of brittle material during crushing in a single-roll crusher with block stop on the roll

Processing of bulk materials used in metallurgical industry to obtain necessary grades of size requires application of crushing machines, including a single-roll type. Indicators of crushing process are degree and efficiency of crushing. Degree of crushing is estimated by the ratio of size of initial crushed and resulting pieces, which depends on size of the gap between a roll and a fixed jaw. The Siberian State Industrial University has patented, designed and manufactured a pilot unit, which is a single-roll crusher with block stop on the roll to study crushing process. A series of experiments on different samples (in shape, size and strength) crushing was carried out on the developed unit. Technique of the experiment and the design of a single-roll crusher with block stop on the roll were described. Results of destruction of the samples of isotropic material made of sand-cement mixture of regular (spherical) shape are presented. Samples from isotropic material allow comparison of analytical conclusions of determining position of the plane of action of maximum tangential stresses with experimental data. Samples of anisotropic material (for example, ferroalloy) were also destroyed. It was experimentally determined that the larger is clearance between the roll and the fixed jaw, the larger is the size of fraction of finished product and over-grinding is less than after crushing the same piece with a smaller clearance. The degree of crushing in a single-roll crusher with block stop on the roll cannot be equal to 4 or more. It was proved that destruction of isotropic materials occurs along the plane of action of maximum tangential stresses. Anisotropic materials are destroyed, depending on size of clearance between a roll and a jaw, both on the plane of action of the maximum tangential stresses and on the planes of least resistance.

Recent Patents on Roll Crushing Mills for Selective Crushing of Coal and Gangue

Background: Gangue is the concomitant product of coal mining. The traditional approach for gangue treatment is to transport it from underground to ground level to accumulate and form gangue hills. Objective: On the basis of summarizing previous research results, this paper introduces the hydraulic roller crusher and the electric machine built-in coal gangue roller crusher, which avoids the complex transmission problems caused by the movement of the central axis when the roller crusher is allowed to roll. Methods: The hydraulic counter-roll crusher directly separates large pieces of coal and underground gangue such that large pieces of coal gangue do not escape from the well. The electric machine built-in roller crusher is an explosion-proof electric machine used in the crushing roller. Results: Both of these crushers can be used in the selective crushing technology of coal gangue in a coal mine and can meet the requirements of crushing different material sizes and generally avoid the centre of the roller crusher. Conclusion: Both of these crushers reduce transportation costs, minimise land occupation, prevent surface subsidence, decrease environmental treatment costs, reduce environmental pollution, and decrease the transport volume of gangue underground. Various patents have been discussed in this article.

POWER ANALYSIS OF THE PROCESS OF BRITTLE MATERIALS DESTRUCTION IN UNIVERSAL CRUSHING MACHINE WITH ROLL LOCKER

The processing of friable materials used in metallurgical industry for production of definite size classes requires operation of crushing machines, including single-roll machines. Parameters of crushing process are degree and efficiency of crushing. The crushing degree is estimated by the ratio of dimensions of the initial crushing and resulting pieces and depends on the size of gap between the roll and the fixed jaw. Crushing efficiency is determined by mass of material crushed by consumed electric energy unit, and depends mainly on strength of crushed material. In order to reduce energy consumption needed for crushing, a single-roll crusher was developed at Siberian State Industrial University with forced feeding of crushing piece into the fracture zone due to the locker located on the roll. Forces of technological resistance appearing during machine operation are the main initial values for machine drive power and structural elements strength testing, thus, the operation power analysis is an integral stage in the design of any machine, including a crushing one. In the present work, forces acting on a crushing piece from roll side and fixed jaw in vertical and horizontal planes are identified. Based on the results obtained, it was determined that internal compressive forces acting on piece of crushing material cause action of normal compressive stresses in a piece, as well as an internal torque effect, which causes shearing stresses action, i.e. a complex stress state is generated in a fractioned piece with simultaneous action of normal and shearing stresses, under which action a fractioning piece is destroyed. Thus reduction in energy consumption for crushing is achieved, with all other conditions being equal. It reduces energy consumption of a single-roll crusher with forced feeding of material into the crushing zone.