sag mill trommel screen
In the image case below, strangely enough, Metso is the mill shell liner and discharge grate manufacturer. The grates it provides to this Cu/Pb/Zn operation are 15mm X 30mm. This operation ordered a polyurethane trommel screen, from Metso, that looks like this:
Trommel screens have been used with varying degrees of success to provide tramp oversize protection for pumps and cyclones following the mills. In addition to conventional trommels, internal oversize return arrangements are available, eliminating the need for external return conveyors to the feed end of the mill. The disadvantages of this design are the inability to observe the nature and quantity of this recycled material and lack of discriminate control over this part of the mill charge.
What is sad about this it the mining operator was ill advised. This trommel is 1 (26mm) in opening . This means next to now oversize will be returned to the SAG and the Ball Mill will be buried is coarse oversize material it will not be efficient at grinding.
Vibrating screens are also often used to provide tramp oversize protection. In addition they can be used to achieve a classifying function, either singly or in combination with sieve bends or cyclones. Pebbles for secondary autogenous grinding can be separated from the slurry stream as can worn balls.
A number of different mill control schemes have been tried in the past and are still being tried. These range from constant tonnage to constant horsepower, to mill sound, to mill total load monitoring.
If an autogenous or semi-autogenous mill is to be controlled under the constant tonnage concept, the mill must be selected to be oversized, so that the hourly tonnages will average out to the desired daily tonnage. Power must be available for ore conditions which require higher than average power per ton. The whole philosophy of this concept does not allow for making better than average tonnage.
If the mill is run on a constant power concept the tonnage will vary depending on the autogenous quality of the ore. It will sometimes be average, sometimes higher and sometimes lower than average, but because of the control concept, this scheme will generally average a higher daily tonnage than the constant tonnage concept because controls are always pushing for maximum tonnage under this condition.
The use of mill sound, and concepts to measure total load in the mill such as bearing pressure, have met varied success. Of the two, the use of bearing pressure to monitor total load in the mill and to act as an over-ride control in conjunction with the constant horsepower concept provides some interesting advantages. Instantaneous mill overloading and plugging is reduced along with the danger of overloaded components such as bearings, heads and shells.
trommel frames and screen media | flsmidth
FLSmidth has fully engineered a new range of trommel frames and screen media for SAG Mills, ball mills and scrubbers. As your partner in productivity, we combine our in-depth knowledge of equipment and applications, providing a comprehensive approach to improve your processes.
All mines want to reduce unexpected events and downtime. Withour trommel frames, you can rest assured that your equipmentis of the highest quality engineered to be strong and lightweight,and designed to increase your uptime and provide safe handling.
To extend and maximise your asset life, we verify the structuraldesign of our trommel frames through finite element analysis (FEA).This guarantees the engineering behind all components of the frames. Completedesign using anFEA calculation includes static and fatigue/strength assessment, as well as strength assessment on the bolts.
We stress relieve your trommel frame afterfabrication and beforemachining. We also apply protective lining on each frame inthe areas that are likely to be exposed to erosive and abrasive wear.
To ensure rapid delivery and streamline inventory management, ourscreening media is available in two standard sizes and in a numberof thickness combinations. Our modular screen media panel sizesare 657 mm 400 mm (25.86 in15.75 in) and 726 mm 400 mm(26.75 in 28.58 in). These standard dimensions allow us to supplyyour media from any FLSmidth manufacturing centre, and guaranteeyour media will conform to our unparalleled quality requirementsand material specifications, while providing equal fabricationreproducibility.
Our experienced engineers are committed to finding thebest solutions. We examine every aspect of your screeningprocess to help ensure efficient pulp flow characteristics, proper separation, maximum wear life and maximum equipment uptime.
We use our state-of-the art discrete element modeling (DEM)software to simulate your trommel performance. We then model,predict, optimise and enhance your assets for the highest possible recoveries and efficiencies.
We offer screening media in a variety of steel and polyurethane grades and rubber composites. Our newest grade of polyurethane media was developed as we partnered with a trusted prepolymer supplier to combine the physical properties of rubber and polyurethane elastomers. This new addition to our offered materials has been proven in the field to be tough and long lasting even under harsh operating conditions.
As a leading supplier of mineral processing equipment, we have many years of experience with the advantages and limitations of each type of media so that we can provide media recommendations that are as customised as your processes. Triple your panel wear life.Download our recent trommel panel case study.
Our media optimisation assistance works to improve production because we start with an array of the highest quality media options and then we perform an in-depth analysis of your product, feed and operating conditions to determine the best material for you.
As part of our efforts to help you select the best media for your needs, we use technological tools such as discrete element method (DEM) software. We use the software to simulate pulp flows through the surface of your screen. With this information we can project the discharge rate, wear patterns and material distribution over the screen.
In the end, this process reduces your operating and maintenance costs. One of our recent customers found that their wear life was tripled when they allowed us to help them with their media selection and did a trial of our newest grade of polyurethane. Download our recent case study here.
Customised trommel frames and screen media make every step of your process better. With proper optimisation help, you get the operation improvement youre looking for while at the same time increasing the ease and safety of the related procedures.
Our unique trommel frame design has friction-grip clip rails for installing the modular panels, as opposed to bolts or pins, reducing your downtime for screen maintenance. The customised screen material options decrease maintenance frequency by maximising wear life.
The washing system is custom-designed and manufactured to deliver efficient washing and recovery of fines that adhere to oversize material. These fines are undesirable, as they can interfere and affect
downstream processes, such as pebble crushing.
FLSmidth provides sustainable productivity to the global mining and cement industries. We deliver market-leading engineering, equipment and service solutions that enable our customers to improve performance, drive down costs and reduce environmental impact. Our operations span the globe and we are close to 10,200 employees, present in more than 60 countries. In 2020, FLSmidth generated revenue of DKK 16.4 billion. MissionZero is our sustainability ambition towards zero emissions in mining and cement by 2030.
principal design of trommel screen - crushing, screening & conveying - metallurgist & mineral processing engineer
Hello, i want to ask about trommel screen, i had a project to design a trommel screen, but i so confused about the principal to make a trommel screen design, i dont find a principal on internet, if anyone have a book/pdf about that, please share the link below. in picture below is my example design with :
thanks Mike. Most of Richards' books are here https://archive.org/search.php?query=creator%3A%22Robert+Hallowell+Richards%22 and https://catalog.hathitrust.org/Search/Home?lookfor=%22Richards,%20Robert%20H.%201844-1945.%22&type=author&inst= for free.
The first item to understand is a Trommel Screen is at least 5 times or more less efficient than a vibrating screen. I would suggest you do a area size calculation and see how much area you would need. The decline of the Trommel will just increase the material velocity. I would also install lifter bars on the inside of the trommel circumference evenly spaced about a meter long a tapered to the discharge end. This will push the material forward and allow more material to enter the feed end. The drive will depend on what mass you wish to move,
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different types of screening equipment - constro facilitator
Screening equipment consists of a drive that induces vibration, a screen media that causes particle separation, and a deck that holds the screen media and the drive and is the mode of transport for the vibration. It is used during the mechanical screening processes, designed to separate one material from another. As the second part of the material handling process, screening equipment is used to separate raw material from a crusher or quarry into even finer grades, coming closer to an end product. There are two types of screens [wet and dry], totally dependent on the raw material. Wet screens utilize spray nozzles and water along with screen vibration in the sorting process, while dry screens use vibration only.
Trommels are widely used in gold mines since they are extremely efficient and very effective at recovering fine gold. The larger-sized models can handle impressive volumes of gold-bearing gravel when operating at peak efficiency. They are often powered by large diesel or electric engines. Modern trommel screens are highly efficient in the separation and processing of wood chips, topsoil, compost, light demolition waste, domestic waste and aggregates. Their rotating drums roll larger pieces of material to allow all fines to flow down and through the trommel screen plates. The latest models feature a highly efficient engine and hydraulic drive system combined with an advanced material processing control system offers maximum production combined with minimum costs. It is ideally suited for screening compost, biomass, soil, gravel & waste. Trommel Screens are attached to the end of grinding mills and scrubbers to perform a variety of screening functions. The trommel screen comprises the rubber-lined steel frame and replaceable screening surface.
Modern high-performance Vibrating Screens machine is engineered to deliver increased productivity and operating benefits compared to conventional spring-mounted vibro separators. With its hygienic design, this circular vibro screen is ideal for applications where hygiene is of utmost importance. Available as a fully stainless steel unit (including the stand) with contact parts. The conventional and general design for a high frequency vibrating screen consists of mainframe, screen web, eccentric bock, electric motor, rub spring and coupler. The two most common types of vibrators which induce the high-frequency vibrations are hydraulic or electric vibrators, these electric vibrators are either electric motors or solenoids. Common designs for screening decks are either single or double deck. Besides, another feature of high frequency vibrating screens is the static side plates which provide benefits such as smaller support structure, less noise, longer life, and hence less maintenance.
New age Disc Screen is adopting the patented anti-clogging system, developed for urban and industrial waste through years of experience and testing. The solution involves the isolation of the machine shafts from the material flow in coordination with the liberation of the material through the faceted disk shape. The latest models offer an efficient and cost-effective solution for any high volume screening application. These Screens operate by feeding material from an infeed device to the slope sheet. Smaller material, such as sawdust, falls through narrow openings in the disc, while larger materials like chips, bark and hogged wood continue to move to the end of the screen and fed to a grinder, hog, hammermill, re-chipper, bunker or reject conveyor.
New age grizzly screens have been designed for the toughest applications capable of high capacity and the ability to process abrasive material. These screens have a very robust design, which allows them to operate under tough conditions (primary or secondary). They particularly perform very well when used to remove the fines between two crushing stages. New series grizzly screens are equipped with many features enabling high efficiency and ensuring various operational advantages. These advantages reduce maintenance and servicing costs, along with necessitating less downtime. Grizzly screens can provide either linear or circular motion and each type offers its advantages. Linear motion grizzly screens work best for scalping ahead of primary cone crushers in mining applications, while circular motion grizzly screens for heavy-duty medium to fine pre or post-screening. Primarily used for the heavy-duty screening of undersized materials in bulk material handling applications, the most common industries that utilize grizzly screens include mining, construction, foundry, recycling and industrial.
New generation revolving screens help to overcome problems such as blocking or sticking screens in screening wet adhesive materials. The yield and reliability of the screen have been greatly increased. The application of screen materials includes various properties, such as coal, gangue, coke; hydrated lime and other easily plug wet materials. Be used in power plants, coking plants, building materials, metallurgy, chemical, mining and other industries.
The banana screen is designed by injecting a banana-shaped multi-stage working surface based on a linear classifier. There is a larger slope screen at the feed end, followed by a stepwise decrease at a certain number of angles until the discharge opening, the overall screen surface is concave curved. The sloped screen at the feed end allows for more material to pass through the screen surface with higher screening speeds and thinner material delamination. Modern banana screening machines achieve good separating accuracy at an extremely high feed rate and with difficult-to-screen material. Its operational behaviour makes it a high-speed screen. Compared with conventional vibrating screens, the banana screen handles a considerably larger feed quantity for the same screen area. Different gear unit sizes enable outstanding setting-up to suit your specific application. Balance masses and speeds can be adjusted in stages, enabling linear vibration amplitude and screen box acceleration to be optimally adapted to meet process requirements.
Elliptical-motion screening machines are driven by two centric main shafts, which generate a swing diameter as in a free-running drive. Another synchronized shaft transforms the swing diameter into an ellipse defined by its task. The second shaft distorts the swing diameter into an ellipse. The big advantage of these machines is that they can work with a very low inclination or with no inclination at all. or The elliptical-motion screening machine combines the advantages of linear- and circular-motion screens as well as enabling space-saving horizontal installation and high material throughput. Both mechanical and electronic elliptical-motion screens can be selectively varied and adapted to operating conditions. This is done by, amongst other things, altering the throw angle essential for transport speed and by adaptation of parameters important for acceleration of the machine, such as vibration amplitude and speed.
Modern horizontal screens are equipped with two vibrating motors rotating in opposite directions. This dual motor configuration in the Horizontal Vibrating Screen causes the screens frame to vibrate in a linear or straight-line motion perpendicular to the plane of the motors. Normally, the motors are positioned at an angle of 50 degrees concerning the screens surface. This results in an excellent forward conveyance of oversize particles, even when the screen frame is in an uphill position. Depending upon the application, the horizontal vibrating screens frame can be positioned from 10 degrees uphill to 15 degrees downhill. Maximum capacity is achieved in the uphill position, causing the formation of a pool at the feed end of the machine. The head or pressure from the pool increases fluid throughout. The horizontal vibrating screens of the screens frame efficiently conveys the oversize particles out of the pool area where they are then discharged.
The vibrating Inclined Screen is the most popular type of screen. There are various types of Inclined Screens, including two and four bearing, high-speed, and high-frequency screens. The overwhelming majority of installations today are either two or three decks, though there are single and four-deck varieties available as well. Modern models are designed with operator safety in mind. Side plates feature cross beam inspection ports that allow you to inspect the inside tubes for failures when the tube is not visible due to abrasion-resistant lining, thus eliminating the need for operators to crawl between decks for inspections. Foreign material that can corrode or abrade the inside of the cross members and cause premature failure can be flushed out via cross beam inspection ports. The eccentric mechanism features jacking bolts in the mechanism tube to support the eccentric shaft during bearing change-outs, eliminating the need for a crane to suspend the shaft or the chance of the shaft tipping over and injuring workers, creating a safer work environment and decreasing downtime.
Mobile screens are utilized in construction sites, aggregates production, quarries, and mining operations whenever movable but high capacity screening is required. The latest models come with high-quality components and engineering without compromises ensures trouble-free production. When service is required, it can be done simply and easily through easy-to-access maintenance points.
Screening equipment needs to match the project to ensure it can stand up to the job and function in the right environment. The mining, aggregate and mineral processing industries are the biggest users of screening equipment. These are often used in quarries and mines. With technological advancement the demand is ever-increasing. There is a need for customization of screening machines and the manufacturers are focusing on that.
vermeer introduces new tr5300em trommel screen
Vermeer expands its electric-powered recycling product line with the addition of the new TR5300EM trommel screen. This new trommel screen is powered by an industrial-duty, fan-cooled 60-hp (44.7-kW) electric motor, and delivers a drum speed of 0-24 revolutions per minute to handle multiple material types, including compost, topsoil and wood biomass. The quiet operating TR5300EM also features a low hopper infeed with a capacity of 5.5-yd3 (4.2 m3) and includes new service and operating enhancements. The Vermeer TR5300EM is an excellent addition to recycling and organic material processing companies looking to help reduce exhaust emissions, noise levels and maintenance.
According to Jay Van Roekel, product manager for Vermeer Recycling and Forestry products, the demand for electric equipment to process organic material is growing, and the TR5300EM complements the line of electric recycling and processing equipment Vermeer produces. Many of our horizontal and tub grinders are available with electric motors, as well as the TR626EM trommel screen, he explained. The TR5300EM is a more compact unit than the TR626EM, making it an excellent option for processing facilities located in urban environments and companies looking to reduce emissions and maintenance.
The hydraulically driven drum on the TR5300EM is 15-ft (4.6 m) long and 5-ft (1.6 m) in diameter to optimize material processing and deliver a high-quality end product. Quick-change screens and a quick-change drum help make it convenient and quick to perform sizing adjustments. The TR5300EM also features several access doors to help with servicing and a set of dual-hinged doors on both sides of the machine for full access to the drum at ground level.
The TR5300EM trommel screen overs and fines conveyors are adjustable to help with dust control and allow for precise placement of material. The unit is also equipped with auto overs flaps to help contain material and reduce spillage.
Vermeer also designed this electric trommel screen for ease of maneuverability and transport. A lot of electric recycling processing machinery in the market is stationary, explained Van Roekel. However, the ability to move a machine can help make servicing and cleaning more efficient. The TR5300EM is built on a single-axle frame, making it possible to transport it to another jobsite or move it into storage when its not in use, as well as making it convenient for a person performing maintenance or cleaning up material around the unit.
The TR5300EM can be equipped with several optional accessories, including a grizzly screen to sort out oversized material and a magnetic head pulley for removing unwanted metal. It can also be outfitted with an auger drum and a hopper extension.
Vermeer delivers a real impact in a progressing world through the manufacture of high-quality environmental, agricultural, underground construction, surface mining and tree care equipment. With a reputation for durability and reliability, that equipment is backed by localized customer service and support provided by independent dealers around the world. To learn more about Vermeer, products, the dealer network and financing options, visit vermeer.com.
Vermeer Corporation reserves the right to make changes in engineering, design and specifications; add improvements; or discontinue manufacturing at any time without notice or obligation. Equipment shown is for illustrative purposes only and may display optional accessories or components specific to their global region.