complete iron ore crushing circuit screening plant mobile

complete iron ore crushing circuit screening plant

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mobile crushers | mobile crushing plant

Based on more than 30 years' experience in the industry development, installation of thousands of sets of equipment and a large amount of money invested in research and development, SBM has released a brand-new mobile crushing and screening plants including seven modules and a total of about 70 types. Our mobile crushers are able to be widely used in phases such as coarse crushing, intermediate crushing, fine crushing, ultra fine crushing. sand-making sand washing, sand shaping and screening in fields of metal mines, building aggregates and solid waste treatment, etc. Also they are able to meet customers' requirements for diversification, high quality and high production capacity, and committed to providing customers with comprehensive and systematic integration solutions.

Our mobile crusher can be used in one stage of crushing for separate operation or complete joint operations with other crushing and screening portable plants to achieve two-stage, three-stage or four-stage crushing, so that various crusher screening requirements could be satisfied.

The mobile crushers feature flexible configurations, with more attention paid to complete functions, stable performance and strong practicability. The reasonable matching among all systems of the equipment has greatly improved the equipment productivity, and compared with the fixed production lines of the same equipment conditions, this products feature more reliable performance, more powerful functions richer function portfolios, significantly enhanced complete capacity and wider applications.

This machine adopt a modular design concept that the same frame can be adapted to a variety of types, so that different host machine units of the same type could be exchangeable. The on-site needs can be satisfied only by changing the main machine equipment according to users' diversified needs.

Mobile crusher has been optimized in structure design and product portfolio, so it has more types and more flexible combinations, able to provide users with more abundant and effective portable solutions

The equipment adopts a universal frame and a modular designed main machine, able to realize rapid upgrade and replacement, so that higher demands of production lines could be satisfied. The frame-mounted platform needs no additional investment, but only replacement of the main equipment and its accessories to upgrade and expand the scale of a stone production line.

The equipment is provided with a preliminary screening module and an adjust-able vibrating screen, the equipment parameters can be adjusted and optimized according to Users' field conditions to optimize the on-site produc tion efficiency.

The speed of the vehicle-mounted belt conveyor can be adjusted according to the material throughput to reduce the energy consumption. At the same time, a feedback alarm system for overload electronic control signals is additionally provided to achieve timely power-off shutdown in case of any fault.

This complete sets of equipment can accurately meet customers' various requirements for crushing operations by means of simple adjustment, and the users can switch "screening first and then crushingto crushing first and then screening according to their individual needs to satisfy the product requirements. Users can also add a returning charge conveyor to realize swit ching between closed and open loops to expand the range of equipment applications.

Compared with stationary crushing plant, this mobile crushing plants can be configured with quick-mounting outrigger steel plates as options free of base hardening and fixation, and can be quickly fixed for working on the site to realize the effect of small range movement approximately like caterpillar equipment, so such have considered the flexibility and the equipment portfo-lio diversification of mobile crushing and screening lants.

Each crushing solution will be different from others due to different feeding types or product requirements, and the K-series mobile plants can provide users with: the maximum flexibility and cost effectiveness able to meet all portable crushing and screening requirements.

delivering plantwide control for arriums iron knob mine | rockwell automation australia

Arrium Mining is an exporter of hematite iron ore and also supplies iron ore feed to Arrium's integrated steelworks at Whyalla. The business currently exports approximately 9-10 million tonnes per annum of hematite ore, primarily to China.

Iron Knob is located in the Middleback ranges approximately 60 kilometres north west of Whyalla, South Australia. It is said to be the birthplace of Australian steel with commercial mining dating back to the 1890s.

Arrium engaged Striker Australia to prepare infrastructure to access the ore reserves in the Iron Knob mine. Striker provides quality, reliable and tough crushing, screening and materials handling equipment to the mining and related industries.

The task at hand was to design, supply, assemble, install and commission modular crushing and screening equipment to process hematite iron ore sourced from the Iron Knob Mining Area for rail transport to Arriums port facilities with minimum ground works and in a short on-site construction timeframe.

To achieve this, Striker Australia contracted SAGE Automation, a Solution Partner of Rockwell Automation and leading provider of industrial automation and control systems. The company is committed to deliver the highest technical solution and customer service, leading with Rockwell Automation technologies and this project was no exemption.

SAGE Automation was contracted to supply the control system and visualisation together with the complete electrical design, construction and installation works for the new crushing and screening plant.

The Iron Knob crushing and screening plant was designed to have a 10 year life expectancy, making the use of mobile crushing and screening equipment as a more cost-effective solution compared to a fixed infrastructure solution.

The plant was originally estimated to cost approximately $40 million, but by using mobile equipment, this cost was able to be reduced by half, said Christopher Poetsch, Senior Electrical Engineer at SAGE Automation.

Poetsch knew that the control and visualisation solution from Rockwell Automation would provide the required flexibility and reliability for this application. As a result of the maintainability and easy integration of the solution into the systems at the site, Rockwell Automation is the control and visualisation vendor of choice for Arrium Mining.

According to Greg Schultz, executive account manager at Rockwell Automation, By having the crushing in close proximity to the mine, the requirement for transport and materials handling is reduced dramatically.

The modular design of the plant made integration easy and also delivered the flexibility required to adapt to changes. The new plant has had a number of design revisions but because it is modular and mobile, it has been easy to adapt to changes, explained Jonathan Deluao, Principal Control Systems/Maintenance Engineer at Arrium Mining.

The overarching control requirements for the entire plant including the conveyors, crushers, feeders and stackers were provided by Allen-Bradley ControlLogix. With safety being a vital consideration for the plant, Allen-Bradley GuardLogix - with local and distributed safe POINT I/O modules provided integrated safety control and the ability to stop either a particular piece of equipment or a section of the plant if required.

Due to the size of plant, over 75 variable speed drives were required. The more complex of these were from the Allen-Bradley PowerFlex family, used for the synchronisation of the vibrating feeders and for the speed control of the conveyors to optimise flow rates to the crushers. FactoryTalk View Site Edition (SE) supervisory-level HMI software is used for monitoring and controlling the plant. It provides operational insight into the complete site, including the conveyors, crushers and feeders.

Using the Rockwell Automation platform for control and visualisation of the plant provided peace of mind, reliability and improved maintenance response times. The plant operators are familiar with, and have confidence in, the ControlLogix and FactoryTalk platform. Because it is used on other Arrium sites, maintenance requirements are also reduced, explained Poetsch.

Using the Rockwell Automation platform for control and visualisation of the plant provided peace of mind, reliability and improved maintenance response times. The plant operators are familiar with, and have confidence in, the ControlLogix and FactoryTalk platform. Because it is used on other Arrium sites, maintenance requirements are also reduced, explained Poetsch.

One of the most significant challenges the project team faced was the extremely tight timeframe. To deliver the project within these timeframes, we leveraged previous project experience, industry knowledge, SAGE Automation team agility, and the use of the Rockwell Automation tools for the design and deployment of the control system, which proved to save significant time and cost, said Poetsch.

Due to the delivery sequence for the crushing and screening equipment, it was necessary to start commissioning sections of the plant while others were being mechanically and electrically installed. Poetsch explained that the use of POINT I/O for the system allowed for flexibility in design and scope changes, right through to the commissioning and handover phase, which helped to deliver the project within time and budget.

Integration between plant equipment was made easy with the Integrated Architecture platform from Rockwell Automation which we stipulate as a standard for Arrium sites. This allows us to benefit from common spares and resources, minimises training requirements and helps the plant capitalise on the core infrastructure, said Deluao.

The high availability of the ControlLogix control system and associated components gives Arrium the assurance of a high mean time between failure (MTBF) and mean time between repair (MTBR) and low mean time to repair (MTTR), which ultimately equates to minimal downtime, planned or unplanned.

Integrated Device Level Ring (DLR) connectivity was used to optimise the network architecture, increase its fault tolerance and provide consolidated network diagnostics. The Allen-Bradley Stratix switches included integrated DLR connectivity, and although the control system did not require redundancy to the level of other Arrium plants, the DLR network topology delivered a reliable network architecture for the plant.

The site now processes approximately five million tonnes of ore per annum and the control system has been embraced by operators and maintenance staff with minimal training. The system was designed and installed to meet Arriums stringent requirements, which are not only site specific but company-wide, said Poetsch.

Rockwell Automation Australia and Rockwell Automation New Zealand are subsidiaries of Rockwell Automation, Inc.a leading global provider of industrial automation and information solutions that helps manufacturers achieve a competitive advantage in their businesses. The company brings together leading global brands in industrial automation which include Allen-Bradley controls and services and Rockwell Software factory management software. Its broad product mix includes control logic systems, sensors, human-machine interfaces, drive controllers, power devices, and software.

Rockwell Automation, Inc. (NYSE:ROK), the worlds largest company dedicated to industrial automation and information, makes its customers more productive and the world more sustainable. Headquartered in Milwaukee, Wis., Rockwell Automation employs approximately 22,000 people serving customers in more than 80 countries.

joyal-crushing plant,stone crushing plant,crushing plant manufacturer

The JOYAL 600-700TPH Jaw & Cone Crushing Plant a crushing and screening system, which includes GZD1500*6000 vibrating feeder,PE1200*1500 jaw crusher,ZYS66"-B cone crusher,2YZS2460 vibrating screen,B1200*25M belt... > Learn More

The JOYAL 400-500TPH Jaw & Cone Crushing Plant a crushing and screening system, which includes GZD1300*4900 vibrating feeder,PE1000*1200 jaw crusher,ZYS66"-B cone crusher,2YZS2460 vibrating screen,B1200*22M belt conveyor and... > Learn More

The JOYAL 250-300TPH Jaw & Impact Crushing Plant a crushing and screening system, which includes GZD1300*900 vibrating feeder,PE900*1200 jaw crusher,PF1315 impact crusher,3YZS1860 vibrating screen,B1200*21M belt conveyor and... > Learn More

The JOYAL 250-300TPH Jaw & Cone Crushing Plant a crushing and screening system, which includes GZD1300*4900 vibrating feeder,PE900*1200 jaw crusher,ZYS51"-B cone crusher,3YZS1860 vibrating screen,B1200*21M belt conveyor and... > Learn More

The JOYAL 180-200TPH Jaw & Impact Crushing Plant a crushing and screening system, which includes GZD1100*4200 vibrating feeder,PE750*1060 jaw crusher,PF1214 impact crusher,3YZS2160 vibrating screen,B1000*20M belt conveyor and... > Learn More

The JOYAL 180-200TPH Jaw & Cone Crushing Plant a crushing and screening system, which includes GZD110*4200 vibrating feeder,PE750*1060 jaw crusher,ZYS51"-B cone crusher,3YZS1860 vibrating screen,B800*17M belt conveyor and... > Learn More

The JOYAL 150-160TPH Jaw & Impact Crushing Plant a crushing and screening system, which includes GZD1100*4200 vibrating feeder,PE750*1060 jaw crusher,PF1315 impact crusher,3YZS1860 vibrating screen,B800*17M belt conveyor and ... > Learn More

The JOYAL 80-100TPH Jaw & Impact Crushing Plant a crushing and screening system, which includes GZD960*3800 vibrating feeder,PE600*900 jaw crusher,PF1214 impact crusher,3YZS1848 vibrating screen,B650*16M belt conveyor and... > Learn More

The JOYAL 80-100TPH Jaw & Cone Crushing Plant a crushing and screening system, which includes GZD960*3800 vibrating feeder,PE600*900 jaw crusher,ZYS36"-B cone crusher,3YZS1848 vibrating screen,B650*16M belt conveyor and... > Learn More

The JOYAL 40-60TPH Jaw & Impact Crushing Plant a crushing and screening system, which includes GZD850*3000 vibrating feeder,PE500*750 jaw crusher,PF1010 impact crusher,3YZS1548 vibrating screen,B500*15M belt conveyor and ... > Learn More

The JOYAL 40-60TPH Jaw & Cone Crushing Plant a crushing and screening system, which includes GZD850*3000 vibrating feeder,PE500*750 jaw crusher,PYB900 cone crusher,3YZS1548 vibrating screen,B500*18M belt conveyor and... > Learn More

crushing & screening plant

Methods used in Crushing & Screening Plantsonore range from a simple combination of a grizzly and one crusher to an elaborate arrangement in series of grizzly, jaw crusher, screens, and rolls or cone crushers.

Crushing is done underground at a few large mines. In general, the jaw crusher is the most suitable primary machine, yet many gyratories do the first breaking. There is a wide choice of these machines. Wearing parts are of special steel, especially hard-faced at the point of greatest abrasion. For secondary and tertiary crushing, gyratories and cone crushers are used, the latter particularly for final reduction, but this can also be done by rolls, which give a uniform product.

The problem of ore comminution involves equipment that will handle the large pieces of rock resulting from mining operations and turn out a product of the relatively small particle size necessary for successful gold extraction. This size reduction is almost always carried out in two successive steps; coarse crushing (dry) followed by fine grinding (wet). Dry crushing is seldom carried below about -in. particle size, experience having shownthat the breaking of material beyond this point is more satisfactorily accomplished by wet methods. On the other hand, there is a trend today toward feeding considerably coarser material to rod mills which function to some extent as wet rolls.

An efficient crushing and screening plant almost invariably employs the principle of stage reduction, with grizzlies, trommels, shaking or vibrating screens interspersed between stages to separate out the material that is already fine enough to by-pass the next step. The grizzlystationary, rotary, or reciprocatingis suitable for the first stage, but thereafter the trommel or screen is more positive in its separation. Few trommels are used, except those on dredges and in sand and gravel plants.

Coarse crushing or breaking is the primary mechanical step in ore reduction. It is frequently done underground in large plants such as theMcIntyre and Hollinger mines. Where sorting is done, it is usually at the shaft mouth, although central plants may be used.

As regards primary crushing machines, the choice is limited to two typesthe jaw crusher and the gyratory. The jaw crusher is, of course, a reciprocating-action machine, crushing rock by direct pressure between a fixed plate and a swinging jaw.

The gyratory crusher, on the other hand, consists essentially of a circular shell with inner sides inclining toward a central orifice. A central shaft passes vertically through this opening and is hung centrally from a spider, which spans the opening at the top. This shaft is eccentrically moved at the bottom and is equipped with a conical crushing head, which operates between the inclined sides of the shell, crushing rock between the head andshell. The crushing operation in this machine is continuous and rapid. It is able to clear itself when completely buried in its feed.

In selecting the proper type of primary crusher a balance must be established on the basis of the largest size of rock to be crushed and the total quantity of material to be handled in a unit of time. It is also to be borne in mind that the product of the gyratory is much more uniform in size than that of the jaw crusher.

Cone crushers are a modification of the gyratory type in that the conical crushing head is eccentrically mounted on a vertical-drive shaft that is supported entirely from below. The top crushing mantle is spring loaded to take care of tramp iron and overloads, and the clearance between the crushing faces is adjustable by rotation of the top assembly which is attached by a heavy threaded connection to the frame of the machine. The Nordberg Manufacturing Co, madethe Symons standard cone crusher for normal-size reduction and the Symons short-head crusher for fine crushing operations.

Older plants operate jaw crushers for crushing ahead of stamp mills, but in the newer ones, jaw crushers break the ore prior to sorting, and gyratories are used for the finer reduction ahead of tube or ball mills. Cone crushers are used in a few plants, and probably more will be installed. While jaw and gyratory crushers compete for primary crushing, gyratory and cone crushers share the secondary field.

This is not the most economical method yet is the practice in many crushing stations. Some method of feeding a crusher regularly is preferable. This may be done by means of a feeder or gate to the bin above the machine or by a heavy chain, a pan feeder, a shaking grizzly, or an apron feeder, which occupy little head space. The objective is to ensure a regular feed to keep the crusher steadily occupied and thus flatten the power curve. Figure 8shows an apron feeder-jaw crusher arrangement. Cone crushers and rolls, particularly, may be fed by belts or drum feeders; cone crushers sometimes are fed from chutes.

A typical Ross chain feeder consists of six lengths weighing 5 tons. The feeder is driven by a 5-hp. motor through a bronze worm reducer, with a sprocket chain-gear and pinion arrangement. This gives a speed of 19 r.p.m. and a capacity of 175 tons an hour.

This practice has been adopted on a number of properties, particularly in Canada. At the Kerr-Addison and Hollinger properties the ore is crushed underground in jaw crushers to 4- to 6-in. pieces before being hoisted to the surface. The same schemeis followed at the Pamour-Porcupine mines and at the McIntyre Porcupine, where the underground crushers make about a minus 7-in. product.

At the Golden Cycle custom plant, Colorado Springs, treating Cripple Creek and other ores, a 5-ft. Symons cone crusher is fed with ore of 3 to 4 in. maximum size which has passed over a vibrating screen having 0.18- by 0.9-in. openings. The Symons produces 100 tons an hour of -in. material for further comminution.

At the Premier mill, British Columbia, the mine-run ore is dumped on a grizzly of 80-lb. rails, spaced at 12 in. A Stephens-Adamson apron feeder delivers the grizzly oversize to an 18- by 30-in. jaw crusher set at 3 in.

Secondary crushing may be done by jaw or gyratory breakers or by cone crushers. In the surface plant at the Mclntyre-Porcupine a 7-ft. Symons cone crusher (see Fig. 11) set at 7/16 in., crushes material from the mine breaker. A 200-hp. motor with V-belt connection drives the crusher.

Second-stage crushing at Loreto, Pachuca, Mexico, is as follows: 4-in. ore from the first crusher, combined with the undersize of a grizzly above it, is passed over two Symons 4- by 8-ft. rod deck screens, the oversize of which is fed to two Symons 5-ft. standard secondary crushers, making a -in. product. Each is driven by a 225-hp. motor and V belt and consumes 172 hp.

The third step in crushing, or tertiary reduction, depends upon what is required. Two-inch or smaller pieces from the secondary crushers may be fed direct to stamps, rod mills, or ball mills, but it is more usual to use a third dry crusher to reduce the ore to - or 5/8-in. size before wet crushing,particularly in the case of ball milling. For such work the Symons short- head machine is well suited, just as the standard machine is for coarser reduction.

The Hollinger crushing plant is one of the largest and most up-to-date plants in Canada. Of steel and concrete construction throughout, high headroom is provided so that, with the exception of a single lift through shuttle conveyors to Nos. 2 and 3 screens, there is gravity flow to all machines (see Fig. 10).

The ore is crushed underground to minus 6 in. and hoisted to 140-ton surface bins. From there it is fed to a 7-ft. Symons cone crusher after passing over a double-deck screen that removes 1-in. undersize from the crusher feed. The product of this crusher plus the product of all other crushing units in the plant is then conveyed to the secondary screens which are situated at the top of the building. These 6- by 14-ft. vibrating screens separate out the 4- by 7/16-in. undersize for storage in a 200-ton bin, fromwhich point it is fed by roll feeders into six 5- by 10-ft. tertiary screens that make a final undersize (3/16 by in.) for transfer to the mill bin. The oversize from the secondary screens is crushed in a 5-ft. Symons short- head crusher set at 3/8 in., and the oversize from the tertiary screens crushed in a set of 78- by 20-in. rolls set at 3/16 in- Both machines are closed-circuited with the secondary screen, and in this respect the flow sheet differs from the four-stage crushing at McIntyre Porcupine, where each crusher is separately closed-circuited with its respective screen.

The crushing plant has a maximum capacity of 440 tons per hour and carries a circulating load of about 2:1 over the final screens and 1200 to 1400 tons per hour over the secondary screens. The plant is completely equipped for dust control with some 40,000 cu. ft. per min. of air drawn through the cyclones, and 60,000 cu. ft. per min. of air through roof vents.

On account of the large volume of air being displaced, it is quite impossible to attempt to heat this building in the winter, and there is only a difference of a few degrees between inside and outside temperatures. Heated cubicles are provided for the operators.

The crushing plant at the McIntyre Porcupine has been changed over in recent years from a three-stage to a four-stage operation. The mine ore is first crushed underground to about 7-in. size, then hoistedto the surface and stored in a 700-ton ore bin. From here it is fed to a standard 7-ft. Symons cone crusher which discharges to two Symons rod deck screens with the -in. slots set transversely to the flow of ore. These screens are closed-circuited with a 5-ft. Symons short-head crusher, and the undersize is passed to a bank of six 4- by 6-ft. Hummer screens having 3/16- by 5/8-in. openings. The oversize passes to the fourth stage of crushingTraylor 78- by 18-in. rolls, the product of which is returned to the screens, while the undersize passes to the mill bins. See Table 5 for the analysis of Crusher house products.

The Hadsel mill (see Fig. 12) is a new type of wet- crushing device which has found limited but interesting application. A large wheel, up to 24 ft. in diameter by 4 ft. wide, is fitted with internal buckets. As the wheel revolves, the buckets lift the rock to the top of the mill where it is dropped onto stationary breaker plates. The ore is thus crushed by its own impact on the plates. Ore as large as 12 in. is fed to the mill.

The 7-ft. Symons discharge is separated on Symons screens into + in. and -in. fractions. These screens are in closed circuit with the 5-ft. short-head Symons crusher. Symons screen undersize is Hummer screen feed. Hummer screens are in closed circuit with the rolls.

The following notes are quoted from the article Three Years of Operation with a Hadsel Mill by George A. Bell. E. and M.J., Vol. 141, No. 1, p. 32,which, describes an installation at the Demonstration Gold Mines, Ltd., Baguio, Philippine Islands:

The capacity of the mill operating on a 12-in. feed and crushing through a 1-in. punched plate was 20 tons per hour, and power consumption about 3 kw.-hr. per ton of ore. The manganese-steel breaker plates lasted approximately 4 months, and other wearing parts 12 months.