Crushing, Screening & Conveying

Crushing, Screening & Conveying

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Started by Leocent
Our ore is a very clay minerals, thus in the scrubber, very hard "clay balls" is forming become oversize of our screens and then send to the reject, but those clay balls contains low grade nickel and cobalt. (we are a ore preparation plant of nickel ...
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Last replied to by rob riggir
Hi Leocent, Clay balls are always an issue with the basic scrubber design, the rolling action being perfect for their formation. There is a way to overcome this issue, but a redesign of your feed pr...
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679
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Started by aweaver
I am learning about various comminution tests and I was wondering how people have previously handled CWi with whole PQ core. I realize that sample size should be between 2" and 3". Should these samples always be crushed versus cut due to the diameter...
Last commented on by Mike
As decribed by Jorge, see: https://www.911metallurgist.com/blog/bond-impact-crushing-work-index-procedure-and-table-of-crushability
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608
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Started by Adilbek Rustemov
Hello everyone,  Is there someone who has an experience with different dust suppression reagents for the coarse ore stockpile area?  I know that Golden West supply some good products; however, I would like to know more about other suppliers and t...
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Last replied to by Jem Tuck
Get hold of Benmarc.  Not sure if I can post commercial info, but they know what they doing and I have no commercial interests.  
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Started by TFulton
Metso 54x74 Mk1 crusher at a Cu mine in BC When the concaves got worn this crusher started packing, leading to high motor amps and motor overheating. What is the mechanism of packing? Why does it occur?
Last replied to by Mike
The most common cause of packing is an increase in clay/soft feed, with a crusher volume increase due to the wear and a soft orethis can lead to build up on the surfaces, especially if there are groov...
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2307
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Started by Sarah
Hello, I have a question about coal crusher. Why do we choose impact and roll crusher on coal? Why can't we choose cone crusher? Please help
Last replied to by Proman
Cone crushers have limitations in terms of the maximum feed size they can handle. If the feed material exceeds the crusher's capacity, it can cause blockages and reduce efficiency.
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Started by ppquintal
Hi. What is the best type of backing compound to use between the mantle and the main shaft in a gyratory crusher? Is it an epoxic base material? The mantle is turning around the shaft, meaning that the locking mechanism is not working anymore. Wh...
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Last replied to by Smilewei
we have gyratory crusher
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Started by Jorge Quintanilla
Hello Everyone.i am envolving in a new expansion project en Bolivia. There was a discussion about foundation of crusher equipments, traditionally We use a concrete foundations. But i worked in one plant with steel foundation and we had a big vibratio...
Last replied to by Proman
Steel is cheaper than concrete and faster to erect, but comes with a longer lead time. Due to its lower fire resistance, insurance premiums for steel structures tend to be higher.
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1629
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Started by Dachmann
Hi, I am new to the field of mining. Recently I looked into the process of liberation and concentration. Many papers suggest that HPGR and Stirred Mills are a better alternative to SAG and Ball mills in terms of energy efficiency and mineral liberat...
Last replied to by Proman
Stirred mills are used by the mining industry for ultrafine grinding to enhance liberation, and to decrease particle sizes of industrial minerals to tailor functional properties. HPGR technology has ...
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1666
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Started by BrantT
Hi.  I'm re-configuring a circuit and i need to install a DSM screen prior to a Knelson though i am not sure how to size it?  Are there any rule of thumbs or models out there to determine the size and angle of the DSM based on incoming flowrate, % ...
Last replied to by Proman
DSM Screen is a curved concave wedge bar type of stationary screen. The common DSM screen available types are 45°, 60°, 120°, 270°, 300°. Different types have the special applications, they are w...
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768
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Started by kikonatsumo
Hi guys, I want to ask how to size a rotary vibrating screen with single layer and 2 outlets. I want to use the screen to separate course ash and fine ash (under 150 micrometer). I got the mass flowrate of input and output but I don't know how to sta...
Last replied to by Proman
Here I am sharing Working Principle of Rotary vibrating screen, which may be helpful in understanding procedure of sizing the screen."Rotary vibrating screen is designed as a high-precision screening ...
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1096
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Started by Netsie
How does the size setting of secondary and tertiary crushers is related.we do have Hp 200 and Hp300 cone crushers, for a better throughput how do I have to calibrate them related to each other and the feed material which has size of 80mm and should b...
Last replied to by Proman
The ore come from a Primary crusher and be scalped. The coarse material will be crushed by the secondary crusher. Once the secondary has finished with the ore, it will be reclassified by a second set ...
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Started by Fuloshixwa
Good day everyone. Anyone with the belt cut test procedure. The test is used to check if the conveyor belt weightometers are still accurate. Did it once with my supervisor but I cant seem to remember it all. Anyone please? 
Last replied to by Proman
There are a few things to look at when assessing your belt scale.- Environment & scale condition- Scale installation location- Belt scale parameters
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Started by erdenetsogt
Hi everyone? Is VSI good choice for circulating load or over sieve product of tertiary (3rd stage) crusher. The ore has p80=18-20 mm, Bond work index Bwi=15-17 kWh/t.?  How about the CAPEX and OPEX?
Last replied to by Proman
The VSI crushes hard and brittle materials with ease. It is the right choice for handling rock, cement clinker, grinding material, concrete aggregate, and refractory material.
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Started by shayne
Am doing an internship at a mine with a comminution plant, how can I practically apply the laws of comminution to predict energy consumption on a 3 stamp mill .
Last replied to by Proman
There are three laws of comminution: -First law- Rittinger-Second law- Kick-Third law- Bond According to third law, the work consumed is proportional to the new crack length produced by the breakage...
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Started by balan@ce
Hello, The shaft in question is very similar to the Metso GP100S and the shaft has broken as in the attached picture. The vitals were good and the crusher was beginning to give some odd sounds before the operator found that the shaft was broken. Any...
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Last replied to by Smilewei
There may be several reasons:1. Fatigue failure2. Overloading3. Material issues4. Improper maintenance5. Foreign objects In order to prevent the cone crusher shaft from breaking, the following points...
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Started by bettsgauce
How many months does it usually take to set-up a static crusher plant?
Last replied to by Proman
The Static crusher plants requires substantial time to set it up. For instance, a 700 tph plant would take a total of 12-16 weeks to set up from zero date.
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730
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Started by figueroalizcanocarlos
Hello everyone, I have been looking for a formula to the retention time on a mineral rotatory trommel but I'm unsure about one I found in the internet. I want to know if there is a formula for that so I can calculate the average or theorical retenti...
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Last replied to by Romain CADENAT
Good afternoon  I your process is wet process you should use a rotary scrubber before the trommel in order to get a good separation of the ore. If dry process trommel alone is fine. 
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499
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Started by christian tshakambowa
hi everyone my concern is like that :  I am working in a copper concentrator using HPGR for finding Ball mill we are facing with rolls working pressures dropping itself. For becoming normal we are restarting it and affecting the running time so t...
Last replied to by Mike
Most newer roll crushers control the roll set using a hydraulic system  (Older, like 40-50+ yearss ago it was controlled mechanically by setting the space between rolls.)  This means you have a hydr...
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Started by aua kiahla
Hello everybody. I've been studying lately about energy consumption for crushers but I haven't found anything regarding this subject for the screening area. Could someone help me and tell me if it is possible to do this energy estimate for screen?
Last commented on by Mike
If you float your pointer over the section title (Crushing, Screening, & Conveying) it will change clor, then click on that title. New page will open and give you the option of adding a new topic in ...
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803
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Started by wtan
How does presence of shale in mineral processing affect the grinding circuit (mill). Is it just a wear issue with the mill liners? or the efficiency of the grind size.
Last replied to by Mike
As with many thingd, a simple question with a very complex answer, "it depends". First off, shale being fairly friable it grinds easily, but does tend to create a lot of fines.  If you are a cement ...
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Started by alitorabi1369
Hello good time - Thank you for answering some of my questions One of the main problems in rotary kilns in pelletizing plants is the presence of chunks or waste materials 1. What is the main reason for the formation of lump? 2. What is the propos...
Last replied to by Mike
As said before and implied in David's comments, a main cause is in the pelletizing stage where the pellets are created.  Normally you would have a classification step between the pellet formation and...
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Started by Fuloshixwa
Good day guys, I am interning at a Gold mine here in Namibia where we seem to be having way to much water being carried over onto our conveyor belts and later on into our concentrate/tailings bins. This water can be seen as a loss of water from the c...
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Last replied to by xosomienbac
thank 
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1124
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Started by alitorabi1369
Hello good timeI am the hpgr operator of a pelletizing plant. Thank you for answering some of my questions One of the major problems in HPGR is the concentration of the concentrate on the rollers. What do you think is the best solution to eliminate...
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Last replied to by mohammad1364
Hello, if you want do maintenance on tyres, for example replacing a broken or chipped stud or you want to measure gap between tyres to reset the static gap, use high pressure water and wash away that ...
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1061
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Started by pandamanishankar
I am working on budgeting the costs for an copper processing plant and need to estimate potential power consumption of jaw crusher? I have work index, F80 and P80 of the ore. Any guidance is really appreciated?
Last replied to by Alex Doll
The specific energy consumption at the motor input can be predicted using Bond's equation: E = 10 × CWi × (P80–½ - F80–½) where CWi is your work index, F80 is the 80% passing size of the fee...
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Started by LordPage
Please tell me if you know the year, make and manufacturer of this. Ball Mill located in Creede, Colorado USA. This Ball Mill was driven by a Steam Engine (missing). Do you know what Steam Engine would have been used to drive this Ball Mill?Many th...
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Last replied to by David
Hi, no idea as to make or year of this antique. Best I could do is if you gave me the mill's dimensions, I could tell you the Horse Power needed to run it. In any case, where would you get a steam en...
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Started by Nikita Gupta
We are using SAG and ball mills for grinding zinc lead ore. I want to know about the possibility of replacing the same with High Pressure Grinding Rolls (HPGR)s. Would the replacement require any changes in the plant design. What would be the feasibi...
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Last replied to by Peter Murphy
Depends on the application and ore characteristics. Sizing and selection of appropriate equipment for throughput and recirculation loads to be considered. Full evaluation of project aims or objective...
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Started by Nikita Gupta
I would like to understand why do companies use SAG mills instead of Rod mills for grinding these days? Apart from the alleviation of need for secondary and tertiary crushers, is there any other reason for inclination towards the installation of SAG ...
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Last commented on by Peter Murphy
Surely its got to do with the feed size and product reduction size required? SAG mills are used predominantly with feed material with a larger max lump sizes (from primary crushing plant typically i...
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Started by redcastle
I have a small gold project that I am looking at conducting a heap leach trial of around 5,000 tons, I'm looking at the most cost effective way to do the crushing with regards to mobile plant hire as I think outright purchase is unsuitable at this st...
Last commented on by Mike
All clays do not expand on wetting, so it is important to determine the type of clay involved. And those clays that do expand do it upon wetting, whether it is a cyanide solution or just regular wate...
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Started by Eder Figueiredo
Dear Friends, I working on a solution for repairing the spider tapered internal bore of our 60” x 89” primary gyratory crusher , as it has loosed its fit interference due excessive wear and can not hold the spider bushing. The results are freque...
Last commented on by Eder Figueiredo
Thanks my friend. I really appreciate your comments.
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1193
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Started by Mark Pulley
Hi,our project is a pilot plant for a Detrital Ore concentrator pilot plant. Feed 600 metric TPH Max size 12mm Screen size 1mm After the screen, the +1mm -12mm material goes through a cylclone and is then screened again.my query is... Can the sc...
Last commented on by Mike
What kind of details are you looking for? Trommels. scrubbers, or what?
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Started by Reactor
We are looking for expertise in the best grade of steel to use for the internals of a pump to transport a slurry with the following characteristics: Particle size is typically 100 mesh / 150 microns Mohs hardness between 3.5 to 4 Solids content ...
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Last replied to by Reactor
Thanks AshKot1. The device we manufacture is not a pump, however, we need to handle the slurry that is delivered by a pump. I'll work on getting the input pressure from the feed pump and the discharge...
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Started by mhasanmtqn
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 ...
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Last replied to by carman
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 ...
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Started by PMD
Hello everyone, I'm currently preparing for a repair job on an old Allis Chalmers crusher from the 50's of which I have no real information on. I've included a photo of the wooden boards I refer to. Replacing parts is all well and good, we have tho...
Last replied to by Mike
In all probability they are a combination of shim and vibration isolators.  If you decide to remove them you will probably need to jack up the crusher and put large shims under it.  You will also ne...
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1092
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Started by Chromst
Hi all,Is it possible to change the closed side setting of a DDC sizer whilst it is operating? Are the roller and breaker bar positions fixed?
Last replied to by Mike
It is never a good idea to try and adjust any equipment while it is operating.  This can cause major failures and also safety issues.  You should always have the equipment shut down cleaned out and ...
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Started by kwmcb
Greetings, I'm researching sand mining in Morgan County, WV, USA.  In the pre-1930 pulverizing plant I saw the piece of equipment in the attached photo.  Can anyone identify the device to aid me in my research. Thanks,  Kent
Last replied to by Mike
Probably a horizontal hammer mill from the looks.

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