The three tests are: The Bond ball mill work index (Wi BM, or BWi) conducted from a feed size of approximately 2 mm to a product size on the order of 100 µm. The Bond rod mill work index (Wi RM, or RWi) …

The mill originally operated at 16 r.p.m., or 62%, of critical speed, which gave sufficient grinding capacity for the massive sulphide ore. The rod-mill discharge flows to a two-cell bank of rod mill unit cells, where approximately 30.0%, of the total copper in the ore is removed as final grade concentrate. Tailings from the rod mill unit cells ...

Ball mill is suitable for grinding hard materials, such as iron ore, copper ore, slag, etc. If the grinding materials are molybdenum ore, aluminum ash, lime, cement, etc. the processing capacity of the ball mill is stronger. Select a rod mill. Rod mill is suitable for grinding brittle materials, commonly used in materials such as tungsten ore ...

Rod mills are similar to ball mills and use metal rods as the grinding media. Pebble mills use rock pebbles as the grinding media to cause friction and attrition between the pebbles and ore material. Pebble mills may be used when metal balls must be avoided. Autogenous grinding ...

for fine grinding (<0.1 mm) while rod mills were efficient for th icker and harder particles in the feed. It ... increased breakage of round particles of the raw ore compare d to those produced by ...

Rod mills are very similar to ball mills except for the use of steel rods as grinding media. In the rod mill, steel rods grind the ore by rolling and rotating. The feeding of rod mill is 50 mm, and its output particle size is …

SAG & AG Mills can be sized according to any of the most appropriate methods of rock hardness testing like SPI, JK, Barrett and Starkey. This discussion will be limited to testing for selection of rod and ball mills. Rod and ball milling, using grinding media of known qual­ity, are well established and require much simpler grinding test ...

rod mill grindability tests. As discussed earlier in this paper, it is important in this case to match the reduction size of the test to that desired from the industrial mill. As such, …

Grinding Mills: Ball Mill & Rod Mill Design & Parts Common types of grinding mills include Ball Mills and Rod Mills. This includes all rotating mills with heavy grinding media loads. This article focuses on ball and …

Therefore, rod mill has the function of selective grinding, and its products are uniform in particle size and overgrinding is slight. The rod mill is mainly used for …

grinding mills. Our rod mills have been manu-factured since 1925. Applications The rod mill, a tumbling mill characterized by the use of rods as grinding media, grinds ores, coal/ coke, and other materials for both wet and dry p- a plications. The rod mill accepts feed ore as coarse as 1 1/2" top size although better performance is obtained

A SAG mill, or semi-autogenous grinding mill, is a type of machine used in mining and mineral processing operations. It uses the crushing and grinding action of rocks to reduce materials such as copper ore into smaller pieces for further processing. Unlike traditional mills that rely on steel balls or other media to break down materials, SAG ...

The true densities of the grinding media and the ore were 8.0 and 2.35 t/m 3, respectively. Forty percent of the mill volume was filled with grinding rods. ... It was, therefore, ground in a wet rod mill 2.85 m × 4.27 m using steel rods of 4.11 m in length. The total mass of the rod charge was 63.8 t. The test work index was 13.2 kWh/t. During ...

The size of 30 mm was optimum for raw materials of −0.45 + 0.15 mm and −0.15 mm. The optimal ball size distribution was 12 mm (40%), 20 mm (40%), 32 mm (10%), and 40 mm (10%) for dry fine-grinding of calcite ore. Finer ball loads were unable to break coarser particles nipped in the feed.

grinding media in a grinding mill with about 26-30 wt.% chrome by Chen et al. [37] using a phosphate ore in a modified ball laboratory ball mill whose electrochemical potential could be controlled.

Though mill length is limited by manufacturing constraints for the grinding rods, our Rod Mills are available in diameters from 5 feet up to 15 feet. Designs extend to 15 feet in diameter by 21 effective feet in length. ... Suitable for coarse ore feed Our Rod Mills are suited to grind coarse materials like limestone, potash, coal, phosphate ...

The roller press, also called high-pressure grinding rolls (HPGRs), has been successfully used for over 25 years in increasing the surface area of iron ore concentrates for pellet feed production ...

Crushed ore is fed to the ball mill through the inlet; a scoop (small screw conveyor) ensures the feed is constant. For both wet and dry ball mills, the ball mill is charged to approximately 33% with balls (range 30-45%). Pulp (crushed ore and water) fills another 15% of the drum's volume so that the total volume of the drum is 50% charged.

Rod Mills = Selective Grinding. Ball Mills = Non-Selective Grinding. Large Balls & Small Rods Compared. Is it better to use a grinding mill with large balls or will small rods? How do you decide …

Rod Mills may be considered either fine crushers or coarse grinding equipment. They are capable of taking as large as 2″ feed and making a product as fine …

Rod grinding process is an ore grinding method which uses a long round metal rod as the grinding medium in a mill to smash the ore. In the rod grinding …

Ball Mill & Rod Mill Design. In all ore dressing and milling processes, including flotation, cyanidation, gravity concentration, and amalgamation, it is necessary to crush and grind, often with rob mill & ball mills, the ore in order to liberate the minerals. In the chemical and process industries, grinding is an important step in preparing raw ...

The Bond rod mill is made of metal, 305 mm maximum inside diameter, with a wave-type lining. The internal mill length is 610 mm. The grinding charge consists of six 31.8 mm and two 44.5 mm diameter steel rods, all 533.4 mm in length, and weighing a total of 33,380 g.

Mill capacity is dependent on: 1. Mill Characteristics (length, diameter, rotation speed, lifters) 2. Feed Characteristics (work index) 3. Reduction Ratio Under given load and particle size requirement, capacity is a function … See more

Grinding and Flotation. Fine ore at minus 19mm (¾") sizing is fed at a controlled rate into the open-circuit 2600mm x 3960mm (8'-6 x 13'-0) Hardinge rod mill at an average feed rate of 2,106 STPD or 87.75 STRH. Rod mill discharge at a nominal size of minus 16 mesh and a pulp density of 75 percent solids combines with ball mill …

Rod mills are similar to ball mills, but instead of using grinding balls, they use long steel rods to do the grinding. The rods grind the ore by tumbling within the mill, similar to the grinding balls in a ball mill. Autogenous Mills. Autogenous mills are designed for grinding ore without the use of grinding media. Instead, the ore itself acts ...

Ball Mill & Rod Mill Design. In all ore dressing and milling processes, including flotation, cyanidation, gravity concentration, and amalgamation, it is necessary to crush and grind, often with rob mill & ball mills, the ore in order to liberate the minerals. In the chemical and process industries, grinding is an important step in preparing raw ...

Why is Ore Grinding Necessary. The reasons for the grinding of industrial materials are numerous but the principal reasons may be summarized under the following headings: ... The rod mill is a mill in …

Submit your question to a subject-matter expert. A two-stage grinding circuit using a rod mill in an open circuit with a ball mill in a closed circuit with a cyclone classifier is used to grind 100 tonnes per hour of ore (S.G. = 3). The circuit layout is illustrated in the Figure below. Assuming that the circuit is sampled and the results are ...

FEATURES: DOVE Supplies three types of Rod Mill with different discharge mechanism, Overflow Mill, End Peripheral Ore Discharge Mill, and Central Peripheral Ore Discharge …