ball mill motor tripping problem

metso global website - metso

metso global website - metso

The combination of Metso Minerals and Outotec has been completed and the new company, Metso Outotec, was established on July 1, 2020. At the same time, Metso Flow Control became a separately listed independent company and started its journey under the name of Neles.

The combination of Metso Minerals and Outotec is completed and the new company, Metso Outotec, started its journey.Metso Outotec is a frontrunner in sustainable minerals processing technologies, end-to-end solutions and services globally.The company helps aggregates, mining, metals refining and recycling customers improve efficiency, productivity and reduce risks.

Metso Flow Control has become a separately listed independent company called Neles. Neles is a flow control solutions and services provider for oil and gas refining, pulp, paper and the bioproducts industry, chemicals, and other process industries.The company's valves and valve automation technologies are known for quality, reliability and highest safety.

how to troubleshoot your pool pump (quick & easy)

how to troubleshoot your pool pump (quick & easy)

If the pump isn't cranking, but seems to turn on okay initially, check your capacitors. You'll either have one or two, and sometimes something called a governor on the shaft end. Make sure the capacitors are not bad and that the governor is closed.

Usually, its because of a bad thread sealant, crack in the pump, an air leak in the suction line, a plumbing issues on the suction side of the pump, or a leaky valve stem. A good way to test for this is with shaving cream.

For repairs involving the pump, its not a bad idea to call a professional or your local pool supply store even if you plan on fixing it yourself: this way you can make sure you're getting the right part and not doing further damage.

make a ball mill in 5 minutes : 4 steps - instructables

make a ball mill in 5 minutes : 4 steps - instructables

This is for all the pyro nuts that I came across on Instructables. This can be used to grind chemicals to a very fine grain or to polish rocks.Wiki says "A ball mill is a type of grinder used to grind materials into extremely fine powder for use in paints, pyrotechnics, and ceramics."Many instructables refer to United Nuclear Ball Mills. Their small ball mill cost between $70 and $80 dollars.For no more than $30 and in 5 minute you can build a ball mill of appreciable performance.Check out my other Instructables:MAKE A HIGH VOLTAGE SUPPLY IN 5 MINUTESHack The Spy Ear and Learn to Reverse Engineer a CircuitSuper Easy E-mail Encryption Using Gmail, Firefox and WindowsMake a Rechargeable Dual Voltage Power Supply for Electronic ProjectsMake a Voltage Controlled Resistor and Use ItSODA CAN HYDROGEN GENERATOR

You need 1. A rugged container (You can use PVC pipes or big plastic bottles) 2. An electric screwdriver (these are fairly cheap, I got mine for $10) 3. A bolt, a nut and maybe a washer. 4. Epoxy putty. 5. Steel or lead balls which in my case I substituted with screwdriver bits that I got for $3. 6. A vise clamp to hold down your ball mill.

This is the most important step. The joint holding the the container and electric screwdriver should be strong and able to hold the weight of the assembly. Put a little putty on the bolt first. Insert the bolt into the screwdriver's bit holder. Cover the whole joint with putty. The more putty the better the ball mill stays together.

Fill the container with the screwdriver bits or with steel balls or lead balls. Add the chemical you need to grind. Close the container and clamp the whole assembly to a table top. I use a popsicle stick to hold the screwdriver button down. I jam it between the clam vise and electric screwdriver (see video). But that depends on your electric screwdriver.

Im interested in this mill to dispose of mercury by combining it with sulphur to make mercury sulphide (HgS).A test report done in EU says an hours milling is best so there is no elemental mercury left.And the mercury sulphide is insoluble and is the same substance that mercury is found in the Earth which is cinnabar.

I may well be able to find a power drill at a resale shop, or buy an inexpensive one for the purpose. Any feedback on how well a power drill motor will hold up to being run for 24 hours continuously? I plan to make paper machie. I want to make a very fine paper pulp. While I doubt this is flammable, I would like to hear any comments on this as well. Who'd a thought flour was explosive?

If you want fine paper pulp, you may wish to consider using a blender. Ball mills are typically only needed for moderately-to-very hard materials that need to be crushed to effectively split them, and which might damage a blender if used in it.

Instead of using an electric screw driver, you could use a drill and a drill bit. Just putty the drill bit (preferably an old one) to the bolt inside the container. Seems like it would be a more powerful ball mill. But I'm definitely going to try this idea. Seems like it would be cool to make some gun powder. There's some simple step-by-step instructions on Wiki How if you guys need some instructions.

I would stay away from lead if you are making gun powder. That smoke that surrounds black powder ignition is not good for you. Fine particles of lead suspended in that smoke would be hell on your lungs etc.. i use a tumbler to get crud off of coins taken from the sea. Beach sand won't work well with water to do the job. But the sand at the oceans edge which is coarse makes a great scrubbing agent. Maybe some aquarium gravel would work to reduce some objects in size. Commercial media is often hell to work with.

hmm... methinks you should support the container. lead balls are heavy and (I'm assuming most people will want to make gunpowder with this so they'll have to use only lead balls) the current setup is going to make the screwdriver wear a lot, and the bottom of the container isn't going to last very long... I like this idea though, I haven't found a suitable motor to drive my ball mill, they're all either too weak or they're way too fast.

I know this is quite literally 10 years late, but for other hobbyists, try supporting it with a screw on the other side like the design pictured. The back end's screw can go through a piece of wood, brick etc. at the same level as the screw driver, creating a healthy amount of support, for a vitamin bottle filled with lead Potassium Nitrate, Sulfur and Carbon.

OR, you could just attach a bolt into the cap like he did for the bottom. Make a triangular piece of wood. Drill a hole for the bolt to fit through. And find some way to support the piece of wood? Seems like it would work to me, could even make your own cradle to support everything for that matter :P I'd never use something like this so have no need to make one, but that would be my advice :D

grinding mills - an overview | sciencedirect topics

grinding mills - an overview | sciencedirect topics

Grinding circuits are fed at a controlled rate from the stockpile or bins holding the crusher plant product. There may be a number of grinding circuits in parallel, each circuit taking a definite fraction of the feed. An example is the Highland Valley Cu/Mo plant with five parallel grinding lines (Chapter 12). Parallel mill circuits increase circuit flexibility, since individual units can be shut down or the feed rate can be changed, with a manageable effect on production. Fewer mills are, however, easier to control and capital and installation costs are lower, so the number of mills must be decided at the design stage.

The high unit capacity SAG mill/ball mill circuit is dominant today and has contributed toward substantial savings in capital and operating costs, which has in turn made many low-grade, high-tonnage operations such as copper and gold ores feasible. Future circuits may see increasing use of high pressure grinding rolls (Rosas et al., 2012).

Autogenous grinding or semi-autogenous grinding mills can be operated in open or closed circuit. However, even in open circuit, a coarse classifier such as a trommel attached to the mill, or a vibrating screen can be used. The oversize material is recycled either externally or internally. In internal recycling, the coarse material is conveyed by a reverse spiral or water jet back down the center of the trommel into the mill. External recycling can be continuous, achieved by conveyor belt, or is batch where the material is stockpiled and periodically fed back into the mill by front-end loader.

In Figure 7.35 shows the SAG mill closed with a crusher (recycle or pebble crusher). In SAG mill operation, the grinding rate passes through a minimum at a critical size (Chapter 5), which represents material too large to be broken by the steel grinding media, but has a low self-breakage rate. If the critical size material, typically 2550mm, is accumulated the mill energy efficiency will deteriorate, and the mill feed rate decreases. As a solution, additional large holes, or pebble ports (e.g., 40100mm), are cut into the mill grate, allowing coarse material to exit the mill. The crusher in closed circuit is then used to reduce the size of the critical size material and return it to the mill. As the pebble ports also allow steel balls to exit, a steel removal system (such as a guard magnet, Chapters 2 and 13Chapter 2Chapter 13) must be installed to prevent them from entering the crusher. (Because of this requirement, closing a SAG mill with a crusher is not used in magnetic iron ore grinding circuits.) This circuit configuration is common as it usually produces a significant increase in throughput and energy efficiency due to the removal of the critical size material.

An example SABC-A circuit is the Cadia Hill Gold Mine, New South Wales, Australia (Dunne et al., 2001). The project economics study indicated a single grinding line. The circuit comprises a SAG mill, 12m diameter by 6.1m length (belly inside liners, the effective grinding volume), two pebble crushers, and two ball mills in parallel closed with cyclones. The SAG mill is fitted with a 20MW gearless drive motor with bi-directional rotational capacity. (Reversing direction evens out wear on liners with symmetrical profile and prolongs operating time.) The SAG mill was designed to treat 2,065t h1 of ore at a ball charge of 8% volume, total filling of 25% volume, and an operating mill speed of 74% of critical. The mill is fitted with 80mm grates with total grate open area of 7.66m2 (Hart et al., 2001). A 4.5m diameter by 5.2m long trommel screens the discharge product at a cut size of ca. 12mm. Material less than 12mm falls into a cyclone feed sump, where it is combined with discharge from the ball mills. Oversize pebbles from the trommel are conveyed to a surge bin of 735t capacity, adjacent to the pebble crushers. Two cone crushers with a closed side set of 1216mm are used to crush the pebbles with a designed product P80 of 12mm and an expected total recycle pebble rate of 725t h1. The crushed pebbles fall directly onto the SAG mill feed belt and return to the SAG mill.

SAG mill product feeds two parallel ball mills of 6.6m11.1m (internal diameterlength), each with a 9.7MW twin pinion drive. The ball mills are operated at a ball charge volume of 3032% and 78.5% critical speed. The SAG mill trommel undersize is combined with the ball mills discharge and pumped to two parallel packs (clusters) of twelve 660mm diameter cyclones. The cyclone underflow from each line reports to a ball mill, while the cyclone overflow is directed to the flotation circuit. The designed ball milling circuit product is 80% passing 150m.

Several large tonnage copper porphyry plants in Chile use an open-circuit SAG configuration where the pebble crusher product is directed to the ball mills (SABC-B circuit). The original grinding circuit at Los Bronces is an example: the pebbles generated in the two SAG mills are crushed in a satellite pebble crushing plant, and then are conveyed to the three ball mills (Mogla and Grunwald, 2008).

Pulverizer systems, which integrate drying, grinding, classification, and transport of the ground fuel to the burners, can present the greatest problems when switching coals/fuels (Carpenter, 1998). Low quality fuels may have grinding properties that are markedly different from the pulverizer design coal (Kitto and Stultz, 2005; Vuthaluru et al., 2003). Consequently, problems are experienced with pulverizer capacity, drying capacity, explosions, abrasive wear of the pulverizer grinding elements, erosion of the coal classifiers and/or distributors, coal-air pipes, and burners.

Whenever there is a loss of a pulverizer, the operator should light oil burner/s to help the operating group of pulverizers to stabilize the flame. At the same time, the operator should bring down the load matching to the capability of the running puverizer/s. Effort should be made to cut in standby pulverizer/s depending on draft fan group capability. Faults in electric supply, if there are any, can then be inspected and rectified. In the case of jamming in the pulverizer internals, the affected pulverizer should be cooled and cleaned and prepared for the next operation.

a pulverizer that is tripped under load will be inerted as established by equipment manufacturer, and maintained under an inert atmosphere until confirmation that no burning or smouldering fuel exists in the pulverizer or the fuel is removed. Inerting media may be any one of CO2, Steam or N2. For pulverizers that are tripped and inerted while containing a charge of fuel, following procedure will be used to clear fuel from the pulverizer:1.Start one of the pulverizers2.Isolate from the furnace all shut-down or tripped pulverizers3.Continue to operate the pulverizer until empty4.When the operating pulverizer is empty, proceed to another tripped and inerted pulverizer and repeat the procedure until all are cleared of fuel

NFPA 85 recommends the pulverizer system arrangement should be such as to provide only one direction of flow, i.e., from the points of entrance of fuel and air to the points of discharge. The system should be designed to resist the passage of air and gas from the pulverizer through the coal feeder into the coal bunker. To withstand pulverizer-operating pressures and to resist percolation of hot air/gas, a vertical or cylindrical column of fuel at least the size of three coal-pipe diameters should be provided between the coal-bunker outlet and the coal-feeder inlet as well as between coal-feeder outlet and the pulverizer inlet. Within these cylindrical columns there will be accumulation of coal that will resist percolation of hot air/gas from the pulverizer to the coal bunker. All components of the pulverized coal system should be designed to withstand an internal explosion gauge pressure of 344kPa [9].

Number of Spare Pulverizers: To overcome forced outage and consequent availability of a number of operating pulverizers it is generally considered that while firing the worst coal one spare pulverizer should be provided under the TMCR (Turbine Maximum Continuous Rating) operating condition. In certain utilities one spare pulverizer is also provided even while firing design coal, but under the BMCR (Boiler Maximum Continuous Rating) operating condition. Practice followed in the United States generally is to provide one spare pulverizer for firing design coal, in larger units two spare pulverizers are provided. However, provision of any spare pulverizer is not considered in current European design [5].

Pulverizer Design Coal: The pulverizer system should be designed to accommodate the fuel with the worst combination of properties that will still allow the steam generator to achieve the design steam flow. Three fuel properties that affect pulverizer-processing capacity are moisture, heating value, and HGI, as discussed earlier.

Unit Turndown: The design of a pulverizer system determines the turndown capability of the steam generator. The minimum stable load for an individual pulverizer firing coal is 50% of the rated pulverizer capacity. Normally in utility boilers, the operating procedure is to operate at least two pulverizers to sustain a self-supported minimum boiler load. Thus, the minimum steam generator load when firing coal without supporting fuel is equal to the full capacity of one pulverizer. Therefore, a loss of one of the two running pulverizers will not trip the steam generator because of loss of fuel and/or loss of flame.

Pulverizer Wear Allowance: A final factor affecting pulverizer system design is a capacity margin that would compensate for loss of grinding capacity as a result of wear between overhauls of the pulverizer (Figure 4.6). A typical pulverizer-sizing criterion is 10% capacity loss due to wear.

The grinder consists of a body with a conical inner surface in which is arranged an internal moving milling cone. The two cones form the milling chamber. On the axle of the internal moving milling cone a debal-ancing vibrator is fitted, which is driven through a flexible transmission. During vibrator rotation, the centrifugal force is generated, leading the internal cone to roll along the inner cone surface of the grinder body without clearance, if material is absent in the milling chamber or across a material layer. Such innercone movement difference is possible owing to the absence in these machines of kinematic limitation of inner cone amplitude. Thus, KID does not have a discharging gap as for eccentric crushers, therefore, the diametric annular between cones is received by coincidence of their axes.

The idea of using the vibrator drive of the cone crusher appeared as long ago as 1925 (US Patent 1 553 333) and then its later versions (German Patent 679 800, 1952; Austrian Patent 200 598, 1957; and Japanese Patent 1256, 1972) were published. In the Soviet Union, the first experimental KID specimens had been created by the early 1950s. Now, in the various branches of industry in the Commonwealth of Independent States, KIDs with capacity from 1 to 300 t/h are produced.

The basic KID feature absence of rigid kinematic bondings between the cones allows the inner moving cone to change its amplitude depending on the variation of grindable material resistance or to stop if a large non-grindable body is encountered; but this is not detrimental and does not lead to plugging. Another KID feature is the nature of the crushing force. In KID, the crushing force is the sum of the centrifugal force of debalance of the inner cone by its gyrating movement. Such force is determined by mechanics and does not depend on the properties of the processed material. The crushing force acts as well on idle running as the result of gapless running in of cones. Therefore, the stability of the inner cone on its spherical support during idle running is ensured.

The grinder consists of a body with a conical inner surface in which is arranged an internal moving milling cone. The two cones form the milling chamber. On the axle of the internal moving milling cone, an unbalanced vibrator is fitted, driven through a flexible transmission. During vibrator rotation, centrifugal force is generated, leading the internal cone to roll along the inner cone surface of the grinder body without clearance if a material that is being grinded is absent in the milling chamber or on this material layer. Such inner cone varying movement is possible owing to the absence in these machines of kinematic limitation of inner cone amplitude. KID does not have a discharging gap as do ordinary cone crushers; therefore, the diametric annular between cones is received by coincidence of their axes.

The idea of using the vibrator drive of the cone crusher appeared as long ago as 1925 (US Patent 1,553,333) and then its later versionsGerman Patent 679,800 (1952), Austrian Patent 200,598 (1957), and Japanese Patent 1256 (1972)were published. The first experimental KID specimens were created in Russia in the early 1950s. Subsequently, in the various branches of industry in the Soviet Union, KIDs with a capacity from 1 to 300t/h were produced. The manufacture of KIDs under license from Soviet Union was developed in Japan in 1981.

The basic KID featurethe absence of rigid kinematic bonding between the conesallows the inner moving cone to change its amplitude, depending on the variation of grindable material resistance, or to stop if a large nongrindable body is encountered. This is not detrimental and does not lead to stopping the debalance. Another KID feature is the nature of the crushing force. In KID, the crushing force is the sum of the centrifugal force of debalance and the inner cone by its gyrating movement. Such force is determined by mechanics and does not depend on the properties of the processed material. This characteristic in combination with the resilient isolation of KID from the foundation allows a two-fold increase in the inner cone vibration frequency.

how i built a quick and easy home-made ball mill

how i built a quick and easy home-made ball mill

Anyone who has looked through my web site can see that I am fascinated with glass. I like to melt it, cast it, fuse it and turn it into new things. Eventually I got the idea of doing the ultimate glass hack and making my own glass from scratch. For that I needed a way of grinding and mixing the chemicals that would make up a batch of glass into a very fine and homogeneously mixed powder. I needed a ball mill. So naturally I decided to build my own. Here it is in all it's bodged together glory. It doesn't look like much, but it works great, and it cost almost nothing to build. As a bonus, this ball mill can also be used as a rock tumbler, or a glass tumbler to make your own "sea glass" at home. To use the mill as a rock tumbler, just leave out the steel balls, add rocks, tumbling grit and water, and let it spin.

Here is a video of my home-made ball mill in operation with a brief explanation of all the parts and how I put it together. For detailed descriptions of all the parts, how I built it, and how I use it, read further down this page.

The drum I used for the ball mill was originally a plastic container that held abrasive grit used in vibratory tumblers. It is about two liters in size. I had several empty containers of this type, and decided to put them to use in this project. They work pretty well in this application. There are a few potential problems. The container lids are not liquid-tight. So use as a rock tumbler would require adding a cork or rubber gasket. Also, a little bit of the plastic does get ground off the inside surface and contaminates the batch being ground. This is not a problem for my application because anything organic will be vaporized out of the mix long before it reaches melting temperature in my kiln. Contamination might be an issue for other uses. A steel drum would probably work better if you can find one, or make one, but it would be a lot louder in use.

Here you can see an overview of the ball mill with the drum removed. Construction is super simple. Just three pieces of wood plank banged together to make a platform for mounting all the parts. The platform is made from a 1X10 wooden plank 14 inches long. It sits on two pieces of 1X4 wood. Four inexpensive fixed caster wheels were mounted on top of the platform for the drum to roll on. They were mounted about 2 inches in from the edges of the platform, and 7.5 inches apart. The drive motor was mounted on the underside of the platform, and the dive belt comes up through a slot in the platform.

Here is a close-up showing how two of the caster wheels are mounted. The slot in the middle of the platform for the belt to pass through is also visible. The fixed caster wheels were quite inexpensive, and were one of the few items I actually had to buy to build this project.

Here is a close-up of the other side of the platform and the other two caster wheels. Also shown is a stop mounted on one side of the platform. It was found early on in using the mill that the drum tended to slowly walk toward one side and would eventually drop off the wheels. So I found a scrap piece of aluminum and mounted it the end the drum walked toward to act as a stop. The drum riding against the smooth aluminum surface doesn't seem to produce much friction.

The ball mill is powered by a fairly robust 12V DC motor salvaged from a junked printer. It had a pulley for a fine-toothed belt on it. It was left in place and it seems to drive the heavy round rubber belt well without slipping. The motor was mounted using screws on only one side, which were deliberately left loose. This allows the motor to pivot downward under its own weight to put tension on the belt.

A long, narrow slot was cut in the platform for the belt to pass through. I did it by marking out where I wanted it, drilling a hole at each end, and then cutting out the material between the holes with a jigsaw.

This photo shows the makeshift end stop that prevents the drum from walking off the casters. It is just a random piece of aluminum I found in my junk collection. It conveniently had some holes already drilled in it which made mounting easy. Just about anything that the drum will ride against nearly frictionlessly will work for a stop.

One of the few things I had to buy for this project, aside from the casters, was the steel balls. I found these online. They were quite inexpensive. I went with 5/8 inch diameter balls, which seem to work well in a mill this size.

I have been powering the ball mill with my bench variable power supply so I could fine tune the rotation speed. I wanted it to turn as fast as possible to speed grinding, but not so fast that centrifugal force pins the balls to the wall of the drum preventing them from tumbling over each other. With a little experimentation, the correct speed was found.

So far, this makeshift mill has worked well for me. It has been run for long periods with no problems. It does a good job of reducing even fairly chunky material into a very fine powder, and thoroughly mixing everything. The only real problem I have faced is accidentally over-filling the drum a few times. The drum should not be too full or the balls and material to be ground won't have enough free space to tumble around.

After a milling run, the contents of the drum are dumped out into a sieve over a bowl. With a few shakes of the sieve, the powder drops through the mesh into the bowl leaving the balls behind to be put back in the drum. The sieve also catches any bits that haven't been sufficiently ground down.

I need to add a disclaimer here for anyone thinking of using this sort of ball mill for milling gunpowder or other flammable or explosive powders. First of all, it is really not a good idea. You could cause a fire or explosion and destroy your place, or maybe even get yourself hurt or killed. So don't do it, and if you do it, don't blame me if something bad happens. I'll be saying I told you so. Also do not to use steel, ceramic or glass balls to grind flammable or explosive materials because they can create sparks as they bang against each other while they tumble.

Future improvements: The plastic container I am using is really thick-walled and sturdy, but using it in this application will eventually wear it out. I also get some plastic contamination in the materials I grind in it. So in the future I would like to replace the plastic container with a piece of large diameter steel or iron pipe with end caps. That should also help improve the grinding action as the steel balls bash against the hard walls of the pipe. If I switch to a steel or iron container, which would be heavier, I might also have to beef up the motor driving the unit. We'll see,

Other applications: As I mentioned at the top of the page, and in the attached video, this setup could also be used as a rock tumbler. The plastic container would be ideal for that. Another possible application for this unit is for grinding samples of gold ore, and maybe other metallic ores. One of my many hobbies is gold prospecting. It's often necessary to grind an ore sample to release all the fine particles of gold it contains so they can be separated. This unit may get used for that in the future too.

[Back to Mike's Homepage] [Email me] Other places to visit: [Mike's telescope workshop] [Mike's home-built jet engine page] [Mike's Home-Built Wind Turbine page] [Mike's Home-Built Solar Panel page] Copyright 2014-2018 Michael Davis, All rights reserved.

[Back to Mike's Homepage] [Email me] Other places to visit: [Mike's telescope workshop] [Mike's home-built jet engine page] [Mike's Home-Built Wind Turbine page] [Mike's Home-Built Solar Panel page] Copyright 2014-2018 Michael Davis, All rights reserved.

[Mike's telescope workshop] [Mike's home-built jet engine page] [Mike's Home-Built Wind Turbine page] [Mike's Home-Built Solar Panel page] Copyright 2014-2018 Michael Davis, All rights reserved.

the grind: a z-axis problem

the grind: a z-axis problem

Sometimes it pays to read the directions! I experienced the dreaded z-axis grind that occasionally happens with installations of the CNC Fusion Kit. Check out the video below to hear how I solved the z-axis problem and some tips on making the z-axis installation go more smoothly.

When I jog (command the z-axis to move) the head of the mill would not move as commanded. The stepper motor would occasionally stall and often run in the opposite direction than commanded. There was a horrible grinding sound when the Z-axis would attempt to move.

I left the spring assist connected thinking it would help the stepper motor raise the head of the mill. Turns out, this was the problem. After I disconnected the spring, the z-axis worked perfectly. Now, if I had paid attention to the instructions associated with the CNC Fusion Kit, i would not have had this problem. The instructions specifically state to disconnect the spring assist.

Hi I have a problem with my settings and the error is the alarm and just cant get past that have tried to reset my axis with no joy. Ps.Im n first time user of the cnc hobby and not fermiliar with all settings as jet but Im learning and try to fix it my self so that if I get simular problems hopefully I can sort it my self.

Johan Thanks for reaching out and telling us about your problem. Will you tell me a little more about your problem & I will make some suggestions on how to solve it? What alarm code was sent when you received the alarm? Does you machine use limit switches?

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