ball mill operation and maintenance

ball mill operations and maintenance | training engineering | teknik | it | laboratorium | health safety | oil & gas

Yogyakarta |28 31 Mei 2013 |IDR 7,000,000.00 per participant non residential Yogyakarta |18 21 Juni 2013 |IDR 7,000,000.00 per participant non residential Yogyakarta |9 12 Juli 2013 |IDR 7,000,000.00 per participant non residential Yogyakarta |17 20 September 2013 |IDR 7,000,000.00 per participant non residential Yogyakarta |15 18 Oktober 2013 |IDR 7,000,000.00 per participant non residential Yogyakarta |26 29 November 2013 |IDR 7,000,000.00 per participant non residential

DESCRIPTION Having skilled team plays a key role in the optimal utilization of the grinding installation in the cement plant. The operators and process engineers must be able to evaluate all the process variables in order to optimize the production economy. This course provides an in depth understanding of grinding theory and maintenance of the equipment and gives you the tools to audit your own installation. WHO SHOULD ATTEND The course is designed for participants with previous experience in mill operation such as process engineers, mill operators and technicians. SUMMARY OUTLINE

industry news-shanghai clirik machinery co., ltd

1.Before the start ball mill, you should check whether the connection bolts are tightened, and tightening condition of the spoon head of the ore feeder, and key of gears, couplings. And, you should check that whether the fuel tank and oil in reducer is sufficient, whether the entire lubrication device and instrument with or without defects, and whether Pipeline is open. In addition, Check if there is the Debris which impedes operation around ball mill and classifier. And then turn the ball mill with a crane disk a week, loosening the ball tube and ore charge, and check the meshing of the ring gear and pinion, which is to check whether it is with or without abnormal sound.

ball mill operation -grinding circuit startup & shutdown procedure

After the grinding circuit has been brought up to normal operating conditions, the operator must monitor the various process variables and alarms. Most of these variables are monitored in the mill control room, however, the operator is also required to sample and analyse process streams and read local indicators.

The ball mill is susceptible to variations in ore hardness resulting in various grinds at constant throughput, or alternatively, various tonnages at constant grind. The variation in grind is not directly determined. However, a changing cyclone overflow density, at a constant tonnage rate and feed density, would be indicative of changing ore hardness and in that case the tonnage fed to the ball mill should be changed accordingly.

The ore feed rate to the ball mill is controlled by the weightometer located on the mill feed conveyor which can be manually adjusted with in the control room to give a constant weight reading. The signal from the weightometer increases or decreases the belt feeder speed and adjusts the water addition to the ball mill (as a function of the actual weight reading). Both weight control and the proportion of water can be adjusted in the control room.

The water rationing controller must be adjusted programmatically to give the desired ball mill discharge density (normally 60-65% solids). The ball mill discharge density should be checked manually at regular intervals and adjustment made to water ratio controller setpoint to adjust the ball mill discharge density.

The grinding circuit operator must ensure that the ball mill runs properly loaded and gives the correct ore grind. A major practical indication of mill loading is the sound made by the mill. A properly loaded mill will have a deep rhythmic roar, while an under loaded mill will have a metallic rattling type noise and an overloaded mill will be quite silent.

The operator must manually measure the cyclone overflow and underflow densities regularly. An increase in overflowdensity is indicative of softer ore and will soon be accompanied by a lowering of power draw at the mill and a change of sound indicating that the mill is becoming under loaded. To compensate, feed tonnage must be increased. Similarity, a decrease in the cyclone overflow density is indicative of harder ore and this will be accompanied eventually by a coking of the mill. Feed to the ball mill must be reduced.

In the event of an emergency, the mill feed conveyor is shut down individually or by stopping the operating cyclone feed pump. The ball mill must be shut down separately. All equipmentshutdowns are performed locally or from the MCC located in the mill control room.

operation and maintenance of ball mill,good quality grinding machine for sale,ball mill grinding process dsign | prominer (shanghai) mining technology co.,ltd

3.Check whether there is any debris around the grinding machine and the classifier, and then use the crane to turn the ball mill for a week to loosen the ball load and ore in the cylinder, and check the gear meshing for abnormal noise.

(1) The grinding machine is not allowed to work under the condition of overload (ball loading) and insufficient material supply. During use, the grinding medium (ball) is added regularly and quantitatively from the feeder inlet.

It is necessary to stop the miner first, and after the ore in the barrel is processed, stop the motor of the grinding machine, use the lifting device of the classifier to lift the spiral out of the sand surface and stop the classifier.

(1) Minor repairs: once a month, including temporary accident handling, mainly minor changes, focusing on replacing vulnerable parts such as liners, spoon heads, adjusting the meshing of bearings and gears, and repairing leaks.

Prominer has been devoted to mineral processing industry for decades and specializes in mineral upgrading and deep processing. With expertise in the fields of mineral project development, mining, test study, engineering, technological processing.

the operating principle of the ball mill

The operating principle of the ball mill consists of following steps. In a continuously operating ball mill, feed material fed through the central hole one of the caps into the drum and moves therealong, being exposed by grinding media. The material grinding occurs during impact falling grinding balls and abrasion the particles between the balls. Then, discharge of ground material performed through the central hole in the discharge cap or through the grid (mills with center unloading the milled product and mills with unloading the milled product through the grid).

In filling mill by grinding balls on 40 50% and non-smooth liner, the outer layers slip is virtually absent, but the sliding of the inner layers one on another observed in various modes of operation mill. In a monolayer filling mill by grinding media, they rotate around their axis parallel to the drum axis of rotation. Grinding media are not subjected to a circular motion by a smooth lining, even at high speeds. In a multilayer filling mill by grinding media, depending on the rotational speed, there is possible one of the following modes the grinding media motion:

Cascade mode motion of grinding balls carried out at low drum speed. At start-up of a mill, the grinding material rotated by a certain angle and grinding balls start to move by closed path. The curved surface of natural slope is close to the plane inclined at some angle to the horizontal. This angle is equal to a limit angle of rotation. In this mode, the ground material remains in this position, but the grinding balls continuously circulate, rise on circular trajectory and cascade roll to the reference point. There is a zone or core in the central trajectory of the grinding material. This zone is inactive. In cascade mode grinding occurs as a result of crushing and abrasive actions by grinding balls. This mode used in the ball mill with a central discharge.

Waterfall mode motion of grinding media in the mill carried out by the drum rotation speed, ensures the transfer all of the grinding balls layers from a circular to a parabolic trajectory. In this mode, grinding balls rise on circular trajectory and at certain points deviate from it and make a free flight by a parabolic curve.

Weight of grinding balls should be sufficient to grind the largest pieces of crushed material. For efficient operation of ball mills necessary to observe the right balance between balls size and feed material size. If the feed material contains many large lumps and grinding balls cant crush them, it leads to a gradual accumulation them between the balls. As a result, mill suspends own operation. In these cases, need to reduce the size of crushed material or increase the size of the balls. By increasing the grinding balls size, decreases the mill working surface and reduced mill productivity. It is important to follow the degree of drum filling by grinding balls, because with a large filling rising grinding balls collide with falling balls.

Established impact of design mills and lining forms on their productivity. Mills operating with low pulp level, have better productivity than mills with high pulp level. Particularly, productivity of mills with unloading the milled product through the grid approximately 15% higher productivity mills with center unloading the milled product. Productivity mills with smooth lining less than productivity mills with ribbed liner. Mill productivity also depends on other factors: number of the drum rotations, the grinding fineness, humidity and size of the crushed material, timely removal the finished product.

Ball mills characterized by high energy consumption. When the mill idles, the energy consumption is approximately equal to the energy consumption with full mill capacity. Therefore, the work of the mill with partial load conditions is unprofitable. Energy consumption for ball mills is a function of many factors: the physical properties of the ground material its specific gravity and hardness; the degree of drum filling by grinding balls; the number of drum rotations, etc. Ball mills have low efficiency no more than 15%. Energy is mainly consumed on the wear of grinding balls and mill housing, friction; heating the material etc.

The advantages of ball mill there are large unit capacity, achievement degree of fineness corresponding to a specific surface of 5000 cm2 / g, simple construction, high reliability and well designed scientific justification.

The disadvantages of ball mills include their considerable metal consumption and deterioration grinding media, as well as a lot of noise. Most of the energy useless lost during ball mill operation, leading to low it efficiency. But even a significant specific energy consumption for grinding material compensates beneficial effect by using mill. This does not exclude a search energy saving solutions for milling, and this handled by experts from around the world.

grinding technology and mill operations | flsmidth

This course provides an in-depth understanding of grinding theory and equipment and gives operators the tools to audit your equipment and systems. Improving knowledge of grinding technology and mill operations to operate, optimise and troubleshoot ball mill and vertical roller mill grinding installations. Ball mills and vertical roller mills are used for many grinding applications in cement production: raw meal grinding, coal and pet coke, and finish cement grinding. Improving the competences of the team plays a key role in the optimal utilisation of the grinding installation in your cement plant. The operators and process engineers must be able to evaluate all the process variables in order to optimise the mill system production. The grinding technology and mill operations course provides the necessary knowledge to maximise the production rate and promote operational stability while ensuring the grinding systems operate efficiently.

This course provides an in-depth understanding of grinding theory and equipment and gives operators the tools to audit your equipment and systems. Improving knowledge of grinding technology and mill operations to operate, optimise and troubleshoot ball mill and vertical roller mill grinding installations.

Ball mills and vertical roller mills are used for many grinding applications in cement production: raw meal grinding, coal and pet coke, and finish cement grinding. Improving the competences of the team plays a key role in the optimal utilisation of the grinding installation in your cement plant.

The operators and process engineers must be able to evaluate all the process variables in order to optimise the mill system production. The grinding technology and mill operations course provides the necessary knowledge to maximise the production rate and promote operational stability while ensuring the grinding systems operate efficiently.

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.

ball mill liner maintenance and cost saving - eb castworld

Leading supplier of high alloy castings and forgings. There are 4 companies with sales of more than 100 million yuan, across the 4 major areas of wear resistance, heat resistance, corrosion resistance, and machinery

To start with, for better results, the liner should be made up of alloys which are best suited to operating conditions in each plant, are cost-effective and have longer lifetime. However, in order to maintain the good performance of a ball mill, it is necessary to carry out the maintenance work regularly. Replacement of a ball mill liner is one of the things that need to be considered for better performance.

WHEN TO REPLACE A BALL MILL LINER? You do not have to replace a ball mill liner regularly except under particular conditions. The ball mill will usually work for a long time without any damage unless the depth of lining wear is enough to have a serious impact on safe operation and efficiency of a ball mill. If depth of lining wear is serious, you should replace the ball mill liner as soon as possible. This is because a ball mill liner protects the barrel of a ball mill by reducing the friction of abrasive materials and body on it.

WHAT THINGS SHOULD BE CONSIDERED BEFORE REPLACING A BALL MILL LINER? Replacing a ball mill liner is not only a cumbersome task but also, a technical one which requires expertise and high-quality work. Before carrying out this task, you should always take steps for the safety of workers. Additionally, an appropriate ball mill liner replacement will increase the efficiency and working of ball mill for a long time. Moreover, it will also ensure the safety of ball mill.

1. CONSIDER THE SPECIFICATIONS OF BALL MILL LINER Before replacing a ball mill liner, you should consider its specifications such as impact resistance, wear resistance, shape and material of the liner.

2. PROFICIENCY IN OPERATION As mentioned before, replacing a ball mill liner requires both expertise and high-quality work. Therefore, you require a team under an experts supervision who know the installment requirements. In other words, proficiency is required in this operation.

3. SUITABLE ENVIRONMENT FOR REPLACEMENT It is necessary to have a suitable environment for replacement process. Good ventilation system along with suitable temperatures are crucial as the worker will have to enter the ball mill barrel for replacement process. In addition to it, you must circulate the remaining pulp in the ball mill, clean, dust and descale the entire cylinder in order to replace the ball mill liner.

4. PAY ATTENTION TO SAFETY Before removing old mill liner, you should remove the used lining screws. Furthermore, pay attention to the safety of workers so that they may not get injured by ball mill liner.

5. DOUBLE CHECK THE INSIDE AND OUTSIDE OF CYLINDER After replacing the ball mill liner, you should double check the inside and outside of cylinder to confirm that there is no working tools, person and other irrelevant things left in cylinder.

ball mill for sale | grinding machine - jxsc mining

Ball mill is the key equipment for grinding materials. those grinding mills are widely used in the mining process, and it has a wide range of usage in grinding mineral or material into fine powder, such as gold, ironzinc ore, copper, etc.

JXSC Mining produce reliable effective ball mill for long life and minimum maintenance, incorporate many of the qualities which have made us being professional in the mineral processing industry since 1985. Various types of ball mill designs are available to suit different applications. These could include but not be restricted to coal mining grate discharge, dry type grinding, wet mineral grinding, high-temperature milling operations, stone & pebble milling.

A ball mill grinds ores to an end product size of thirty-five mesh or finer. The feeding material to a ball mill is treated by: Single or multistage crushing and screening Crushing, screening, and/or rod milling Primary crushing and autogenous/semi-autogenous grinding.

Normal feed sizes: eighty percent of six millimeters or finer for hard rocker eighty percent of twenty-five millimeters or finer for fragile rocks (Larger feed sizes can be tolerated depending on the requirements).

The ratio of machine length to the cylinder diameter of cylindrical type ball mills range from one to three through three to one. When the length to diameter ratio is two to one or even bigger, we should better choose the mill of a Tube Mill.

Grinding circuit design Grinding circuit design is available, we experienced engineers expect the chance to help you with ore material grinding mill plant of grinding circuit design, installation, operation, and optimization. The automatic operation has the advantage of saving energy consumption, grinding media, and reducing body liner wear while increasing grinding capacity. In addition, by using a software system to control the ore grinding process meet the requirements of different ore milling task.

The ball mill is a typical material grinder machine which widely used in the mineral processing plant, ball mill performs well in different material conditions either wet type grinding or dry type, and to grind the ores to a fine size.

Main ball mill components: cylinder, motor drive, grinding medium, shaft. The cylinder cavity is partial filling with the material to be ground and the metal grinding balls. When the large cylinder rotating and creating centrifugal force, the inner metal grinding mediums will be lifted to the predetermined height and then fall, the rock material will be ground under the gravity force and squeeze force of moving mediums. Feed material to be ground enters the cylinder through a hopper feeder on one end and after being crushed by the grinding medium is discharged at the other end.

Mining Equipment Manufacturers, Our Main Products: Gold Trommel, Gold Wash Plant, Dense Media Separation System, CIP, CIL, Ball Mill, Trommel Scrubber, Shaker Table, Jig Concentrator, Spiral Separator, Slurry Pump, Trommel Screen.