We are interested in cooperation with the manufacturers of screens, who are looking for an official and reliable distributor to deal with supply & delivery of their equipment to the industrial plants in Russia.
The company’s top management and sales team are well acquainted with the Russian market, its mentality and laws; they also understand industrial specifics of the financial and economic activities of the Russian customers. All our sales managers have a large customer database, extensive experience of successful sales and well-established connections with the potential buyers of your screens. This allows our managers to promptly set out the most promising directions for promotion and to ensure a rapid entry of the products into the promising Russian market. Our employees, who are fluent in English and German, are focused on working at the international market with the supplies of foreign equipment.
Our team of experienced engineers, who can handle the most serious technical problems, constantly keeps in touch with the Russian customers, holds meetings and delivers presentations regarding the latest achievements of our manufacturing partners. They point out the engineering challenges and actively communicate with all the departments at Russian plants. That is why the specifics of doing a business in the Russian Federation are well-known to us, and we also know the equipment of the local industrial plants and their up-to-date modernization needs.
Once we become your authorized representative in Russia, our marketing staff will carry out a market research in order to check the demand for screens, will submit a market overview for screens that you offer and evaluate the needs for this type of equipment at local plants. Our specialists will also estimate the potential and capacity of this market at local industrial plants. Our IT-team will start developing a website for your products in Russian. Our experts will assess the conformity between your screens and customer needs as well as analyze the common reaction to the new goods in general. We will look into the categories of potential customers, and pick out the largest and the most promising plants.
Upon becoming your authorized agent on the territory of Russia, ‘Intech GmbH’ LLC (ООО «Интех ГмбХ»), will obtain certificates, if required, for a batch of the goods, for various types of screens in compliance with Russian standards. We can also arrange the inspection in order to obtain TR TS 010 and TR TS 012 Certificates. These certificates provides permission to operate your equipment at all industrial plants of the EAEU countries (Russia, Kazakhstan, Belarus, Armenia, Kyrgyzstan), including the hazardous industrial facilities. Our company is eager to assist in issuing Technical Passports for screens as per Russian and other EAEU countries’ requirements.
Our engineering company ‘Intech GmbH’ LLC (ООО «Интех ГмбХ»), collaborates with several Russian design institutes in various industrial segments, which allows us to conduct preliminary design as well as subsequent design works according to the standards, construction rules and regulations that are applicable in Russia and other CIS countries. It also enables us to include your screens into the future projects.
The Company has its own logistics department that can provide packing service, handling as well as the most efficient and cost effective mode of transportation of the goods (incl. over dimensional and overweight goods). The goods can be delivered on DAP or DDP-customer’s warehouse basis in full compliance with all the relevant regulations and requirements that are applicable on the Russian market.
Our company has its own certified specialists who will carry out installation supervision and commissioning of the delivered equipment, as well as further guarantee and post-guarantee maintenance of screens. They will also provide necessary training and guidance for the customer’s personnel.
Classification is the separation of bulk to a required particle size. Thus, the mixture can be separated into fractions or classes that are limited by specific dimensions of grains or pieces.
The following classification types are used:
Screening is the most versatile method of classification that allows dividing the material depending on its size. This method is used for the classification of the material with the size of 1-250 mm. Air and hydraulic separation allows separation of the grain with a size of less than 2 mm. Classification is needed to prepare the material to crushing or return it for re-grinding. In addition, classification may be used to produce a finished product, which has a specific grain structure. This process is called sorting.
Classification is necessary for accurate determination of the granular composition of the material.
Screening is an independent process, but it can also be a subsidiary process, which is used in the preparation of material for subsequent operations. As an independent process, screening is called sorting, and, as an auxiliary process, screening is called classification. The process of screening is performed using sieves or screens, the main elements of which are the sieves (cylindrical or conical). Small fractions pass through the screen holes, and large fractions remain thereon, thus separating from the fine particles.
Sieves for sieving of materials are made of metal grids or sheets with rectangular or round holes.
The quality of the screening determines the efficiency of screen. Material, pieces of which have different amounts, is subject to the process of screening. Dropouts and waste can be obtained after the screening. Dropouts are particles that have passed through a sieve. Wastes are particles that have not passed through a sieve and therefore go from the other side of the screen. Efficiency depends on the type and the constructive execution of the screen, ranges from 70 to 85% (max. 90%) and is determined by several criteria. Main criteria:
Shape and size of meshes of the screen is one of the most decisive and defining criteria, which depends on the shape of the material particles. If the particles have a regular shape in the form of balls, the cells also have the round form. For other particles can be used oblong, rectangular or square cells. The mesh size is chosen somewhat larger than the particle size.
Regarding the thickness of screen material it is possible to make the following conclusion: the thinner the layer of screen material, the better and more efficient operation of the screen is.
If sortable material is wet, it becomes more difficult to sieve small fractions, because they stick together gathering in clumps and remaining on the screen.
Quality of screening is significantly better at low speed of material movement over the screen and with the small layer thickness. The material should be shaken on a sieve, so that it could better be sorted and pass through meshes. This is provided by the majority of screen designs.
The screen is made of wire sieves or steel cloth, which represent its working surface. The working surface of screen can also be made of grate bars.
The design of the wire sieves represents a grid with square or rectangular holes, the size of which ranges from 0.10 to 150 mm. In laboratory conditions are used sieves with smaller holes, the size of which can be up to 0.03 mm.
Sheets, the thickness of which ranges from 3 to 12 mm, are used for manufacturing of sheet cloth. Such clothes have circular or semicircular holes ranging in size from 5 to 50 mm. The holes are slightly extended towards the bottom, so that they could not be clogged with material.
Grate bars are rods with trapezoidal cross-section. Such a form allows easy passage of material between the grates.
A special set of sieves, the holes in which decrease from the sieve to sieve in a constant ratio, is used to determine the grain size of the bulk material. An average sample of the material is used to perform the sieve analysis. The material that remained in each of the sieves and grain, which has passed through the last sieve, are weighed after sieving. Ratio of obtained weights of the material gives a presentation about the content of the various classes of grains in the used material. Products, which have remained on the sieve, are designated by the size of holes, through which they cannot pass.
Characteristic of granularity of screened material and its particle size distribution can be determined by sieve analysis.
Separation of pieces of material of a certain size occurs during movement of the material relative to the surface of the screen. Relative movement of the material may occur during the motion of the sieve (in a horizontal or inclined plane) or on the stationary screen, which is set at a greater angle than the angle of friction of the material.
The process of separation of the material is very important to improve the efficiency of screening. To achieve this effect, the material pieces are thrown up at a certain rolling frequency of the sieve.
Screens are characterized by two parameters: performance and accuracy. The accuracy of the screening is defined as the ratio of weight of sieving to the weight of the pieces of the same class in the initial product.
The amount of material per time unit, which was obtained from 1 m2 of the working surface of the screen, is used to determine the performance of the machine. Performance may depend on the density, moisture content, size and shape of the material used. Furthermore, a method of supplying the material and size of sieve can also affect the performance. Empirical formula is applied for the calculation of productivity because of the fact that there are many factors that influence it.
Screening may involve one or more successively arranged sieves.
Methods of multiple screening:
Advantages of screening from small to large:
Advantages of screening from large to small:
By mode of action screens are divided into fixed screens and movable screens. By type of lattice screens are divided into horizontal screens and drum screens. Depending on the design of lattice screens are divided into grate bar screens and lattice screens.
Fixed screens are used very rarely, because they have low productivity. The material is loaded onto such screen from trolleys, finer fractions slip into the holes between the grate bars in the screen and the large fractions glide over it, falling into the crusher. The positive qualities of fixed screens include the fact that they are inexpensive, structurally simple and easy to maintain.
Movable screens are structurally divided into:
Disk screens Sieving fraction size is determined by the distance between the disks. The efficiency of the screening is determined by the diameter of the disks and their number.
Roller screens are a series of parallel axes, on which are mounted rollers with the same direction of rotation. Rollers are installed at a certain distance from each other, due to the size of pieces of dropouts.
Chain screens are used for separation of large amounts of lumpy material (usually ore). They represent chains moving along the rollers. Material slips between chains in the process of screening. More bulky pieces that do not fall between the chains are removed at the other end of the screen.
Drum screens are most commonly used in modern industry. The screen is a drum with a grid surface set at an angle. Drum screens are used for the separation of granular materials into more than two classes. Drum screen includes a cylinder with the meshes over its entire surface. The cylinder is placed at an angle and is driven by an electric motor. The connection is made through a reduction gear and a bevel gear. Rollers are used as the support of the cylinder. Thrust rollers prevent longitudinal movement of the cylinder. Material enters through a funnel. After sieving pieces are falling into the hopper, and the pieces that do not pass through the cylinder holes are transported from screen to secondary crushing.
Material sorting on the drum screen is worse than on flat screens (rocking and vibrating). Screens of drum type should not be used for separation of fine materials. Disadvantages:
However, despite the disadvantages mentioned above, drum screens are widely used as they are quite reliable in operation.
Drum cylindrical-shaped screens
Drum cylindrical-shaped screen is an open drum, which can have a polyhedral, conical or cylindrical shape. They are made of a grid or perforated sheets.
The drum rotates on a central shaft, which is mounted on support rollers or outrigger bearings. The drum drive is made by means of gear mechanism. Drum clamping devices are mounted at an angle of about 5°. Holes for the passage of the bottom product are increasing in the course of material.
Multifaceted screens (which are also called rotary screens) are used for fine screening. Such an apparatus has a hexagonal drum, which is closed by casing, from which dust can be sucked. Each face of the drum is a removable sieve. In such devices each sieve can be easily and quickly replaced.
Speed of drum screens is 0.5-1.5 m/sec.
These disadvantages are not very important, so this equipment has almost completely replaced the vibrating and rocking screens.
Rocking screens are also widely used in industry. They represent sieves inclined at an angle and making the vibrational motion by means of cam mechanism.
Oscillatory motion of the screen is carried out by a crank mechanism. The screen is shaking, dropout falls into meshes, and the waste is moved along the sieve, subsequently entering the crusher. Rocking screens are usually made multistoried in order to select several fractions simultaneously. Material flows into the top sieve with the largest holes. Large pieces are removed from the upper sieve as waste, while small pieces enter the underlying sieve with smaller holes. Waste and dropout are generated again. Dropout goes back to a fine sieve, etc. Rocking screens are highly effective at screening of pieces of more than 13 mm.
Horizontal rocking screen
This type of screens is one of the most common. Horizontal rocking screens consist of rectangular box and sieve, which is rocking by means of a moving mechanism. During the rocking of the screen, material moves along the sieve. The upper product is discharged, and bottom product is screened.
In such screens the box is mounted on 4-6 spring rods, which move by means of eccentrics of piston rod.
The length of sieve running, slope of the box and the engine speed are determined empirically in order to achieve the required performance. Typically, the number of revolutions ranges from 300 to 500 rpm.
Horizontal rocking screens are used to classify materials, the size of pieces of which is 50 mm, by wet and dry method.
Among the disadvantages should be allocated only unbalanced structure. Therefore, such equipment cannot be installed on the upper floors of buildings.
Eccentric-drive rocking screen
Vibrator-shaft is mounted in the frame post on ball bearings. These screens are equipped with two eccentrics and counterweights. Box with a sieve is mounted to the shaft on bearings. Box is secured to the springs on the rubber mounts by its ends. The eccentric shaft provides movement of sieve with amplitude that is equal to the eccentricity r of the shaft. Such devices belong to devices of high-speed type, so they are usually hung on the ceiling joists by means of rods with springs.
Vibrating screens are used for screening of fine materials and dehydration of deposits. They are highly efficient and therefore are in great demand in the industry and replace the drum screens. Vibration of body and screen sieve takes place in the vertical plane. These screens have variable amplitude of oscillations. By the method of vibration communication can be distinguished unbalanced-throw screens, impact screens and electromagnetic screens.
Unbalanced-throw screens are used to separate materials into fractions by size. The maximum size of a piece of starting material is 250 mm.
Eccentric-drive unbalanced-throw screen consists of a box, wherein one or two sieves are placed. The box is suspended on the eccentric shaft. The eccentric shaft is mounted on two roller bearings on the main frame. The motor actuates the screen by means of the V-belt transmission. Smaller and frequent fluctuations are transmitted to the box during the shaft vibration. Under the influence of these fluctuations occurs good separation of the material and its high-quality screening.
The performance of such screens is 4 - 300 cubic meters per hour and the vibrational amplitude is 3 mm. The engine has a capacity of 2.0 - 6.0 kW.
The inclined screen in vibrating screens makes frequent vibrations by means of vibrator. Sieve vibrates at a frequency from 900 to 1500 times per minute. The oscillation amplitude is 0.5-15 mm. Elements of such screens are not practically interconnected. Therefore sieve oscillation is uneven and depends on the angular velocity of the shaft and other dynamic factors.
The construction of vibrating screen is the following. On springs are mounted box and sieves. On bearings and racks rotates shaft with two pulleys that carry unbalanced loads.
Rotating pulleys cause a centrifugal force of inertia, which transmits the vibrations to the box. The amplitude of the oscillations of box is determined by dynamic factors. Screens of this type require a uniform presentation of the material.
The same principle is used in electrical-vibrating screens. In such screens oscillation of sieves is carried out by means of electric vibrators or electromagnet, through the winding of which is passed alternating current.
Upon becoming the official distributer of agitators (mixing equipment), our company ‘Intech GmbH’ LLC (ООО «Интех ГмбХ»), carries out the following: finds the buyers of your products on the market, conducts technical and commercial negotiations with the customers regarding the supplies of your equipment, concludes contracts. Should a bidding take place, we will collect and prepare all the documents required for the participation, conclude all the necessary contracts for the supply of your equipment, as well as register the goods (agitators (mixing equipment)) and conduct customs clearance procedures. We will also register a certificate of transaction (Passport of Deal) required for all foreign trade contracts in the foreign currency control department of the authorized Russian bank so that currency transaction could be effected. If required, our company will implement an equipment spacing project in order to integrate your equipment into the existing or newly built production plant.
We are convinced that our company ‘Intech GmbH’ LLC (ООО «Интех ГмбХ»), will become your reliable, qualified and efficient partner & distributor in Russia.
We are always open for cooperation, so let’s move forward together!