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Types of Ore Feeders
Legend: (a) belt, (b) apron, (c) screw, (d) shaking, (e) vibrating, (f) drum, (g) disk, (h) chain
Moly-Cop Tools – Download
Here you will find the Moly-Cop Tools Version 3.0 Download 1 and download 2 collection of Excel files. Also find 2 great little PDF ‘free’ courses at https://www.scribd.com/doc/155884044/Moly-Cop-Tools-1 and https://www.scribd.com/doc/214561051/MCTools-Basic-II http://www.arrium.com/
Molybdenum Grind Size & Liberation VS Collector Dosage for Recovery by Flotation
In an effort to evaluate the metallurgical results of an operating plant, 3 process stream samples (red points) provided were subjected to detailed modal analysis using protocols established for mineralogically similar ores. This method of analysis provides quantitative estimates of the mineral composition and of the mineral fragmentation characteristics. This data can then be used to evaluate the efficiency of the
Molybdenum Flotation
A Molybdenum Flotation case study with about 6% of the molybdenum contained in the feed is present as an oxide form and about 90% of this is not recovered to the flotation concentrate. Recovery of molybdenum into the rougher concentrate varied between 90 to 95% at a concentrate grade of 2.5 to 3.7% molybdenum. The rougher concentrate can be upgraded
Gold Hog Sluice Mat Review
Looking for Gold Hog Matting Reviews I went on a large gold prospector forum and asked the question: What is so special about those Gold Hog Sluice Mats? Here below are all the many answers and comments I received. ———- Hi.It is hard too explain.but many years and testing go into these mats.You should watch the You Tube videos. Each and every
How to SIZE a Sluice Box
Table of ContentsOptimum Slope of a sluiceMotorised Sluices This week I went and asked “how to SIZE a sluice box” to the crew on a large gold prospector forum and other sluice or gravity gold recovery ‘experts’ and gathered the list of emails and forum posts here below. As you will see, in summary, most can optimize or troubleshoot a
Ore Feed Size * Work Index Hardness: Crushing & Mill Tonnage
The single most common reason for an increase or drop in the production of fines is the WORK INDEX of the ore. If you remember, the work index of the ore is a method of measuring the degree of hardness. As the ore becomes harder the fracture lines in the rock become cleaner or sharper with less crumbling of the
Feeder Control -Ore Feed Size and Mill Tonnage
One area of major importance for the identification of impending problems are the feed belts. By visually estimating the PHYSICAL CHARACTERISTICS of the ore it is possible to have advance warning of change in many of the variables. Feed size is the most apparent, if the crush is supposed to be minus 3/8 of an inch, any change in the
Operating a Grinding Circuit -How to Operate
What I would like to do now is expand upon the grinding theory involved. Bring all of the earlier information together and show you how it relates to the operation of a mill and make you capable of Operating a Grinding Circuit correctly. Then I will explain the differences between Rod mills, Ball mills, SAG and autogenous mills and how
Specific Gravity to Density of Pulp or Slurry
As mill operators you don’t have to worry about the mathematics of a Specific Gravity to Density conversion. These specific gravities have all been worked out and are presented in a table form. You simply consult the line that represents the specific gravity of the ore that you are working with, match it with the dissecting line that indicates the weight of
How to Find and Determine the Specific Gravity of a Rock
In the method we use to How to Find and Determine Specific Gravity of Rocks (some call it Specific Density because they don’t know better!), we’ll use simple equipment. What is required to make this measurement is a weight scale, and the list of the different minerals SPECIFIC GRAVITIES. What specific gravity is, is the mass of a solid in relationship
LSSM = Low Speed Synchronous Motor Drive Operation
In the world of mining and milling the “electrical term” LSSM stands for “Low Speed Synchronous Motor” and usually means a mill where the motor rated speed is in the range of 10 RPM, the same speed as the mill turns. A high speed motor can run at 900 RPM and uses a gearbox to turn down the speed. A medium speed motor runs in
Effect of Water & Density on Grinding Mill
The Time that the ore spends in the grinding mill is called, RETENTION TIME. This is a very important variable, the longer the retention time, the more the ore comes in contact with the rods, the better and finer the grind becomes. To understand this important control it must be remembered that any volume that is added to a circuit
Grinding Mill Gear Assembly
We will begin with the mill’s bull gear assembly and work towards the motor, The BULL GEAR, sometimes called the RING GEAR is designed to turn the mill transforming the energy of the motor into motion for the mill. By mill we refer to Ball Mills, Rod Mills and SAG Mills. Anything gear and pinion really. The discharge end of
Leaking Mill Shell Bolts
Dealing with leaking Mill Shell bolts is common enough an occurrence in most concentrator plants. All that an operator can really do about it is to keep the problem to a minimum. The cause of the bolts leaking is running the mill with a density that is to light or feed that requires a high impact to grind. This could either be
Mill Trunnion Liner
Table of ContentsTrunnion Liner SchematicsBALL MILL FEEDERBALL MILL FEED BOXBALL MILL GEAR GUARDBALL MILL MANUFACTURINGBALL MILL HEADS AND TRUNNIONSMILL FEED HEADBALL MILL DISCHARGE HEADROD MILL DISCHARGE HEADTRUNNION LINERS The Mill Trunnion Liner fits inside the bearing to protect it from wear caused by the ore being washed over the liner and through the bearing as it is fed to or discharged from
Trunnion Bearing Assembly Ball Mill & Rod Mill
Table of ContentsBall Mill TRUNNION BEARINGSTrunnion BRONZE BUSHINGSTRUNNION BASE AND CAPBall Mill LUBRICANT JACKSBall Mill PINION SHAFT BEARINGS The first part of the mill that we will look at is the TRUNNION BEARING. This is a HYDROSTATIC BEARING which is a slow moving bearing that carries a heavy load. Usually it is constructed from Babbitt’s metal. If you happen to remember the
How to do a Sieve Analysis
Let me explain as to how a Sieve Analysis is done. If you take a sample of ground ore, heat it until it is completely dry. Take 500 grams of that sample, and place it on top of a set of screens designed for size analysis. These screens have a graduated mesh size. The screen with the largest opening between
Grind to Liberate Mineral Grains
The next piece of information that is of value to the operator is to know the hardness of the ore. The WORK INDEX, as the hardness is referred to, is calculated on the amount of electrical energy that is required to grind the ore to a predetermined size. Said in another way, it is the amount of work required to
Rods or Balls
Mill operators will not get to design too many mills, but this doesn’t mean that the information that has been compiled isn’t of interest to the operator. Knowing the ore body shape, size, and content will give the operator prior knowledge of operating conditions to be expected. It is also beneficial to know how this information is obtained. The clearer
Simple Grinding Circuits & Flowsheets
To start the discussion on grinding circuits I would like to begin by showing you some simple Flowsheet SCHEMATICS of some sample circuits, but before I do there is one thing that I must explain for the schematics to make sense. When the ore is put into the first piece of equipment for grinding, water is added to it to
Ore Bin (Silo) Safety
Around these ore storage bins or areas there are three possible places of work, on top, under, and in. Each one has their own brands of danger, and methods of safety and protection. The dangers of working under these areas are MOVING EQUIPMENT, PRYING ON HANGUPS, STANDING’ON EQUIPMENT and SMALL PLATFORMS WITH LITTLE HEAD ROOM. That old saying an ounce of
Fine Ore Storage Bin and Stock Pile
Let’s begin with fine ore storage bin or stockpile, get it out of the way and then proceed to grinding. You would think that there isn’t that much to learn about when talking of fine ore storage, after all, all that this area is really for is to provide surge capacity for each of the circuits. True, but there are