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The product particle size control is flexible, special design is adopted to reduce noise and emission. Automatic control, easy to operate. According to the scale of investment, it provides personalized customized scheme and provides value-added services.
According to different materials and application industries, the production capacity and particle size range will be different. Please contact our engineers to customize the equipment for you. Our experts will contact you within 6 hours to discuss your needs for machine and processes.
After coarse crushing, the material is fed into the ball mill through a controllable feeding device. The grinding medium in the mill repeatedly impacts and grinds the material by virtue of the kinetic energy obtained when the mill rotates. The crushed material is discharged into the suction tank through the tail of the ball mill, and then transported to the classifier for classification by negative pressure. The qualified fine powder is collected by cyclone collector or dust collector, The coarse particles after classification are discharged from the lower end of the classifier, and then re-enter the ball mill for crushing through the feeding pipe.
Note: The production capacity is closely related to the particle size, specific gravity, hardness, moisture and other indicators of the raw materials. The above parameters are for reference only, please consult our engineers for details.
WINNIPEG, MB / ACCESSWIRE / June 4, 2021 / Winston Gold Corp. (Winston Gold or the Corporation) (CSE:WGC) (OTCQB:WGMCF) is pleased to announce that the necessary upgrades to the Paradine Mill Facility, near Radersburg, Montana, are nearing completion, despite staffing, material acquisition and delivery challenges.
Naturally, with any re-commissioning activity, unforeseen challenges inevitably arise, commented Mr. Murray Nye, CEO and Director of Winston Gold Corp. I must commend our staff at the Paradine Mill facility for their perseverance and dedication during this period. The overall advantages of renovating an old mill still significantly outweigh building and permitting a new one.
Work at the mill is now focused on installing critical new parts (delayed due to shipping issues), in addition to re-configuring and optimizing the floatation circuits. The following points summarize the progress achieved to date:
The Paradine mill facility is being developed into a turn-key mineral processing plant, stated Mr. Joseph Carrabba, Executive Chairman of Winston Gold. The mill lies in the heart of a region blessed with precious metal endowment, and the future value opportunities are significant.
Towards that end, Winston Gold recently formed a joint venture with Bond Resources (CSE:BJB) to test the near-term cash-flow viability of another past producer, the Hard Cash Mine. (Refer to news release dated May 13th 2021). The Hard Cash property is located just 4.3 miles from the Paradine Mill and an initial drill program should commence shortly.
The Paradine mill located just 35 miles (56 km) by paved road from the Companys wholly owned Winston Gold project which is situated near Helena, Montana. The Mill has a nameplate capacity of 150 tons per day and hosts a ball milling circuit as well as both a gravity and flotation circuit. A new lined settling pond has been constructed for tailings disposal with a 35,000-ton capacity and two additional ponds are also being built.
The scientific and technical content and interpretations contained in this news release have been reviewed, verified and approved by Dr. Criss Capps PhD. P.Geol., an independent consultant to Winston Gold Corp. Dr. Capps is a Qualified Person as defined in National Instrument 43-101 Standards of Disclosure for Mineral Projects.
Winston Gold is a junior mining company focused on advancing high-grade, low-cost mining opportunities into production. Towards that end, the Corporation has acquired the under-explored and under-exploited Winston Gold project near Helena, Montana.
The CSE has neither approved nor disapproved the information contained herein. This news release does not constitute an offer to sell or a solicitation of an offer to buy any of the securities in the United States. The securities have not been and will not be registered under the United States Securities Act of 1933, as amended (the U.S. Securities Act), or any state securities laws and may not be offered or sold within the United States or to U.S. Persons unless registered under the U.S. Securities Act and applicable state securities laws or an exemption from such registration is available.
This release includes certain statements that may be deemed forward-looking statements. All statements in this release, other than statements of historical facts, that address events or developments that Winston Gold Mining Corp. (the Company) expects to occur, are forward-looking statements. Forward-looking statements are statements that are not historical facts and are generally, but not always, identified by the words expects, plans, anticipates, believes, intends, estimates, projects, potential and similar expressions, or that events or conditions will, would, may, could or should occur. Although the Company believes the expectations expressed in such forward-looking statements are based on reasonable assumptions, such statements are not guarantees of future performance and actual results may differ materially from those in the forward-looking statements. Factors that could cause the actual results to differ materially from those in forward-looking statements include regulatory actions, market prices, exploitation and exploration successes, and continued availability of capital and financing, and general economic, market or business conditions. Investors are cautioned that any such statements are not guarantees of future performance and actual results or developments may differ materially from those projected in the forward-looking statements. Forward-looking statements are based on the beliefs, estimates and opinions of the Companys management on the date the statements are made. Except as required by applicable securities laws, the Company undertakes no obligation to update these forward-looking statements in the event that managements beliefs, estimates or opinions, or other factors, should change.
Vibroengineering PROCEDIA, Vol. 32, 2020, p. 32-37. https://doi.org/10.21595/vp.2020.21528 Received 10 June 2020; accepted 18 June 2020; published 29 June 2020
Cherkasova Margarita, Samukov Alexander, Goncharov Ivan, Mezenin Anton Influence of the metal chips disintegration method on the physical and mechanical properties of metal powders obtained. Vibroengineering PROCEDIA, Vol. 32, 2020, p. 32-37. https://doi.org/10.21595/vp.2020.21528
This paper presents the results obtained in comparative grinding studies of alloy metal chips using a ball mill and a vibrating mill. A comparison of the effective viscosity, bulk and tapped density in narrow size classes demonstrated higher rheological properties of the vibration grinding product and significant differences in the distribution of indicators by the size classes, depending on the grinding method. The specific yield and energy consumption indicators were established, which confirmed the superiority of vibration grinding over ball mill grinding. A visual assessment of the shape and surface condition of the ground particles is presented, conducted using a scanning electron microscope.
The applications of powder materials and their global usage are growing annually, which is further facilitated by the development of additive manufacturing in mechanical engineering. These advanced knowledge-intensive technologies require very high-quality dispersed powders. Their manufacturing method may directly affect the properties of the metal or alloy used. Powders with identical chemical compositions may have varying physical characteristics and may differ in processing properties, leading to significant variations in the conditions for the further transformation of the powders into finished products [1, 2].
Mainly physical and mechanical methods and melt dispersion methods are currently used for the manufacture of metal powders [3, 4]. At the same time, the waste generated in machining applications is an immense source of raw materials for manufacturing metal powders. This waste is usually generated in the manufacture of critical parts and contains valuable alloying components [5, 6]. For such raw materials, mechanical treatment will be the best method of obtaining powders, ensures the transformation of the initial material into powder without any significant changes in its chemical composition. This will reduce the cost of the powders generated and eliminate the energy-intensive and non-environmentally friendly pyrometallurgical process of waste remelting, which has been used traditionally.
Ball mills are the most affordable and common industrial equipment for producing metal powders by mechanical grinding . Grinding is ensured by impacts, abrasion and crushing: with the drum rotation, the grinding balls are raised by friction to a certain height and then fracture the material by freely falling and rolling.
However, in fine grinding, with finer particle sizes, the relative particle strength increases due to the reduction in the number of pre-fractured areas. The microcracks emerging in the first loading cycles may close under the influence of molecular forces. This self-healing effect of the particles may be reduced by increasing the load application rate and the frequency of exposure to force pulses, thus improving the fracture intensity due to the fatigue phenomena. In the case of a traditional ball mill, the impact intensity of the grinding medium is structurally limited by the so-called critical rotation speed, at which the centrifugal forces start pressing the grinding medium to the drum. These restrictions limit the specific performance of ball mills, which leads to a significant increase in energy consumption in the case of metal and alloy grinding and supports the feasibility of using more energy-efficient and energy-intensive devices.
Vibrating mills are a promising alternative, using similar main exposure mechanisms (impact, abrasion and cracking) to those in ball mills, but with the grinding media accelerations many times higher than the acceleration of gravity fundamentally limiting the traditional ball mills.
The previous studies of vibration crushing and grinding of metal chips  demonstrate the advantages of this type of equipment for obtaining metal powders. However, a better understanding of the physical fracturing processes in vibration grinding and their differences from the fracturing processes in traditional ball mill grinding required further research into the structure and properties of particles by various size fractions, following their comparative disintegration in these devices.
The material for the comparative studies was represented by alloy metal machining chips with the nickel content of 77%, without the metal-working oil. Before the grinding, the chips were crushed in a hammer mill to the particle size of less than 2.5 mm.
For the vibration grinding, an eight-chamber continuous-discharge vibration roller mill was used, with the total chamber working volume of 8.3 liters. The vibrating mill housing was mounted on rubber shock absorbers; the vibrations were induced via an electrically driven unbalanced vibrator; the oscillation frequency was 19.5 Hz; and the oscillation amplitude was 6.7mm. Rollers were used as the grinding media.
Grinding to the particle size of 51.5% less than 125 m was carried out in four stages. After each grinding stage the finished product with the particle size of less than 125 m was separated from the material discharged; the product of over 125 m was used as the feed for the subsequent grinding stage.
The traditional chip milling tests were carried out in an MSL-14K batch-operated cantilever-type laboratory ball mill with the drum working volume of 14 liters. The ball charge was 40%; the ball diameter was 40, 25, and 20 mm, with the percentage ratio of 50:34:16, respectively. The mill rotation rate was 71 rpm (76% of the critical value). The grinding to the particle size of 63.1% less than 125 microns was completed in 87.5 hours.
The grain-size analysis for the fine classes was carried out using a AS-200U (ROTAP) impact testing sieve and Microsizer 201C laser particle analyzer. The research results were used to establish the grain-size characteristics of the grinding products, as shown in Fig.1.
An analysis of the grain-size distribution for the grinding products indicates a certain degree of overgrinding in the ball mill with the difference of 11.6% in the content of the <125 m class and 13.3% for the classes of <74 and <44 m. At the same time, for the coarse classes (over 250m), the particle content remains almost the same, with 16% and 16.9% for the ball and vibrating mills, respectively. These differences in the particle size distribution of grinding products are due to the differences in the grinding conditions. In the vibrating mill, the finished size class (<125 m) was separated from the mill discharge, while the class of over 125 m was returned to the mill for regrinding. In the ball mill, all the material was ground for 87.5 hours, without any intermediate removal of the finished size class, which contributed to the overgrinding.
Since the grinding machines compared operate in fundamentally different regimes (discrete and continuous grinding with coarse class regrinding), for a correct comparison, their performance and energy consumption indicators were calculated as specific values related to the working volume of the grinding chambers of the mills (Table 1).
According to Table 1, the ball mill is significantly inferior to the vibromill in terms of specific performance indicators as related to the working volume. For the feed material, the specific yield of the vibrating mill is 19.4 times higher than that of the ball mill and is 17.5 and 12.5 times higher in the classes of 125 and 74 m, respectively. Moreover, the coarser the size class, the more intensive its fracturing becomes in a vibromill, as compared to a ball mill. The energy consumption for the vibrating mill grinding of metal chips to the particle size of 51.5% <125 m was 2.54kWh/kg, which is 1.64 times lower than the energy consumption for the ball mill grinding to the particle size of 63.1% <125 m (4.16 kWh/kg). However, since a finer product is obtained in the ball mill with the same grinding size, the actual difference in energy consumption will be slightly lower.
For the narrow size classes of the grinding products the values of effective viscosity, bulk density and tapped density were determined. The effective viscosity was measured using a Hall device according to the method set out in ISO 4490-78, but using a non-standard funnel opening with the diameter of 10 mm. Bulk and tapped density values were established using the methods in ISO 3923-2: 1981 and ISO 3953:2011, respectively.
The results obtained (Table 2, Fig. 2) indicate that the vibrating mill product demonstrates fluidity in a wider range of size classes (1250 + 44 m) as compared with the ball mill product (315 + 74 m). The weighted average effective viscosity values in the comparable size range of (315 + 74 m) are also lower (3.9 versus 4.4), which generally indicates higher rheological properties of the vibration grinding product.
The differences in the properties of the grinding products are also manifested in their other characteristics. As may be seen from Table 2 and Fig.3, the vibration grinding product has higher bulk densities (tapped densities) in the range of 2.6 (2.8) to 3.4 (3.7) g/cm3 at finer particle sizes (1250 to 250 m); and a further decrease in the particle sizes to less than 44 m smoothly reduces these values to 2.1 (2.4) g/cm3. By contrast, the ball mill product demonstrates an almost imperceptible drop in its bulk density (tapped density) from 2.3 (2.5) to 2.1 (2.4) g/cm3 with a decrease in its particle size from 1250 to 125 m, a smooth increase to 2.4 (2.7) g/cm3 upon reaching the particle size of 44 m and a sharp drop to 1.2 (1.3) g/cm3 with the further decrease in the particle size. The vibration grinding product has 1.41 times higher weighted average bulk density (tapped density) values than the Ball mill product, with 2.78 (3.09) versus 1.97 (2.19)g/cm3, respectively. The visible differences in the distribution of bulk and tapped densities in the products compared not only indicate significant differences in the shapes of the ground particles, but also describe the differences in the fracturing processes.
For a visual assessment of the shape and surface condition of the ground particles, a TESCAN Mira 3 LMU scanning electron microscope with the 106x magnification and the accelerating voltage of 200 to 30000 V was used to obtain enlarged particle images (Table 3).
A study of the microimages obtained confirms the assumption that the difference in particle shapes causes the discrepancy in the bulk and tapped density values. Table 3 clearly indicates that the ball mill product is represented by plate-shaped and flaky particles in the entire range of particle sizes. It is also noticeable that, due to overgrinding, the class of less than 44 m contains a significant number of particles with the particle size below 5 (10) m, which explains the sharp bulk density drop in this class by the emergence of adhesion forces.
The vibration grinding product particles in the particle size classes of 1250 to 250 m are predominantly close in shape to a ball or a cube; with the further decrease in particle size, plate-shaped and flaky particles gradually emerge and multiply and represent the majority in the class of less than 44 m.
The above differences in the physical and mechanical properties of ground particles may be explained by the nature of the mechanical interaction of the grinding media with the material ground in the devices compared. Based on the microimages obtained, it may be assumed that ball mill grinding with low-energy ball impacts on the particles of metal chips mainly causes surface deformations of the metal, which leads to slow particle splitting into plate-type (flaky) shapes with further cracking-off of finer particles. On the other hand, high-energy impacts of the grinding media in vibrating mills (caused by high accelerations) allow creating deep deformations in coarser metal particles, inducing volumetric cracks and subsequent fracturing with the formation of prevailing cuboid and spherical particles; and the fine size classes formed (less than 74 m) are prone to splitting with the formation of flakes and plates.
1)The specific feed capacity of a vibrating mill exceeds that of a ball mill by a factor of 19.4 and is 17.5 and 12.5 times higher in the classes of less than 125 and 74 m, respectively. Moreover, the coarser the size class, the more intensive its fracturing becomes in a vibrating mill, as compared to a ball mill.
2)The energy consumption for metal chip grinding in a vibrating mill is 1.64 times lower than in a ball mill; however, since a finer product is obtained in ball mills with the same grinding size, the difference in energy consumption will be slightly lower.
3)The vibrating mill product has fluidity in a wider range of particle sizes, as compared to the ball mill product, which generally indicates higher rheological properties of the vibration grinding product.
4)The values of bulk density (tapped density) differ significantly depending on the grinding method in terms of the nature of their distribution by the size classes. The vibration grinding product has 1.41 higher weighted average density values.
5)The ball mill product is represented by plate-shaped and flaky particles in the entire range of particle sizes. By contrast, particles of the vibration grinding product are predominantly close in shape to a ball or a cube in the particle size classes of 1250 to 250 m; with the further decrease in particle size, however, the number plate-shaped and flaky particles increases.Get in Touch with Mechanic