Ball mill is the key equipment for grinding after the crushing process, which is widely used in the manufacture industries, such as cement, silicate, new building material, refractory material, fertilizer, ferrous metal, nonferrous metal and glass ceramics and can be used for the dry and wet grinding for all kinds of ores and other grind-able materials.
Oct 03 2015 · The Titan Bond Work Index Rod Mill is onepiece cast construction with integral wave liners of a form described by Bond This mill is used to perform the necessary metallurgical testing to determine the grinding characteristics of ores and power requirements for
The standard Bond Rod Mill Work Index test procedure is firstly to stage crush the feed to pass 127 mm and size a representative sample The test then involves a series of batch grinds in a standard Bond rod mill A Bond rod mill is 0305m by 0610m with wave liners of a form described by Bond which runs at 40rpm and tilts as described below
The Bond Index conforming rod charge consists of 6 rods of 125“ diameter and 21“ length 2 rods of 175“ diameter and 21“ length The grinding jar for the Bond Index Rod Mill is 12″ x 24″ in size and has a waveshaped design At least 15 to 20 kg sample material is required to simulate a closed grinding circuit in a ball or rod mill
Generally Bond work index is a common method for selecting comminution equipment as well as estimation of grinding efficiency and calculating required power In the current research a simple fast and accurate procedure is introduced to find the rodmill work index based on
FIGURE 5 BOND ROD MILL WORK INDEX v UNCONFINED COMPRESSIVE STRENGTH 0 100 200 300 400 UCS MPa 5 10 15 20 25 30 35 WiRM metric The lack of fit observed relating the crushing Work Index was expected to carry over to the other Bond Work Indices Figure 5 displays the plot of rod mill Work Index Wi RM versus UCS These
Standard Bond crushing and rod mill work indices abrasion indices and by Dawson for Bond Ball Mill Work Index tests using crushed feed and Standard Autogenous Grinding Design SAGDesign Tests patented by Outokumpu See reference 8 below The comparison of these results gives context to how the various measurements relate to each
Table of Bond Work Index by Minerals This Table of Ball Mill Bond Work Index of Minerals is a summary as tested on ‘around the world sample’ You can find the SG of each mineral samples on the other table Andesite 201 183 201 195 Basalt 189 171 188 190 190 Coke Petroleum 745 Emery 625 567 625 625 Fluorspar 119
The Bond Ball Mill Work Index is a measure of the resistance of the material to grinding in a ball mill It can be used to determine the grinding power required for a given throughput of material under ball mill grinding conditions
The Bonds standard ball mill is used to determine the work index value of differ ent samples The Bond work index is defined as the kilowatthours per short ton required to break from infinite size to a product size of 80 passing 100 µm If the breakage characteristics of a material remain constant over all size ranges the calcul ated work index would be expected to remain constant since it indicates the
Rod Mill Power Draft Rod mill power is dependent on mill capacity and work index Mill power increases with Increasing rod charge Increasing mill speed Increasing mill length Rowland and Kjos 1980 provided an expression to quantify power draw at the pinion shaft per unit mass of rods P↓M M↓R 1752 D↑033 63 – 54J↓R Φ↓C kWt
W is the work index measured in a laboratory ball mill kilowatthours per metric or short ton P 80 is the mill circuit product size in micrometers F 80 is the mill circuit feed size in micrometers Rod mill A rotating drum causes friction and attrition between steel rods and ore particles
The Bond ball mill work index is one of the most commonly used grindability tests in mining and is often referred to as the Bond work index The test is a lockedcycle test where ground product is removed from test cycles and replaced by fresh feed
Determining the Bond work indexes of a sample involves tests using laboratory scale grinding circuits A unit weight is determined by achieving maximum packing of the prepared ore sample the unit weight is then fed into the circuit with undersized product being replaced by
The Bond rodmill work index is used in conjunction with Bond’s third theory of comminution to merely calculate net energy requirements for sizing rodmills This test was originally developed in the mid 1930s by FC Bond
Bond Rod Mill Work Index RWi kWht 181 Table 1 Example of AGSAG Ball Mill Circuit Wio Calculations 1 2 ABstrAct Optimum use of power in grinding both in terms of grinding efficiency and use of installed capital can have a large effect on profitability Mill operators have long used operating work indices to evaluate grinding circuit
This test determines the Bond Rod Mill Work Index which can be used with Bond’s Third Theory of Comminution to calculate net power requirements of sizing rod mills The test is a closedcircuit dry grindability test is run in a standard rod mill and can be performed at sizes ranging from 476 mm to
The Bond ball mill work index is one of the most commonly used grindability tests in mining and is often referred to as the Bond work index The test is a lockedcycle test where ground product is removed from test cycles and replaced by fresh feed
Rod Mill Batch Process The mill dimensions D × L are 0204 × 03 m and it is loaded with 855 kg steel rods 14 to 20 mm diameter The mill rotates on rolls and its frequency is set to 70 RPM corresponding to 85 of the critical frequency The mill power is 225 Watts calculated by 6 Fi P
Upon obtaining a consistent IPP the undersize product of the final cycle is sized to obtain a work index Bond Ball Work Index BBWi The sample is staged crushed to 100 passing 335 mm
The work index covering grinding in tumbling mills of coarse sizes is labelled M ia The work index covering grinding of fine particles is labelled M ib Morrell 2008 M ia values are provided as a standard output from a SMC Test Morrell 2004a whilst M ib values can be determined using the data generated by a conventional Bond ball mill work index
This mill has been operating inefﬁ ciently due to the hard coarse feed The rod mill work index has not been de ned as yet The ball ﬁ mill work index is con rmed at 16 kWht The operating ﬁ work index though is in the range of 21 kWht to 25 kWht showing high inefﬁ ciency
The Titan Bond Work Index Rod Mill is onepiece cast construction with integral wave liners of a form described by Bond This mill is used to perform the necessary metallurgical testing to determine the grinding characteristics of ores and power requirements for operating productionsize rod mills
The Bond work index Wi is defined in a Bond ball mill on the samples of standard size − 3327 0 mm
As in ball mills the power draft of a rod mill is the product of capacity and work index which is the energy required to break a mineral of a given size to the required size The mill power is also increased by increasing the rod charge and the mill speed while the mill power and capacity are both increased with increasing mill length
W is the work index measured in a laboratory ball mill kilowatthours per metric or short ton P 80 is the mill circuit product size in micrometers F 80 is the mill circuit feed size in micrometers Rod mill A rotating drum causes friction and attrition between steel rods and ore particles
The standard Bond Ball Mill Work Index test procedure is firstly to stage crush the feed to minus 335mm and size a representative sample The test then involves a series of batch grinds in a standard Bond mill A Bond mill is 0305m by 0305m with rounded corners a smooth lining and runs at 70rpm
For in stance for large particles comminution from 100 down to 10 mm the crushing work index SWI is applicable for me dium size particles from 100 mm to 2100 μm rod milling work index RWI for finer particles ball milling work index BWI Table
Bond Test WI’s kWht Rod Mill Ball Mill 95 kWht8 9 kWht Bond Standard Circuit Work Index Assume the rod mill Work Index of 95 applies from the actual rod mill feed sizeof 19300 mµ although some of this work might ideally be done by crushers to achieve a rod mill F80 of 16000 m to a rod µ
10 mm the crushing work index SWI is applicable for medium size particles from 100 mm to 2100 μm rod milling work index RWI for finer particles ball milling work index BWI Table These indexes are readily obtained using the specialpurpose laboratory equipment Fig
The work index covering grinding in tumbling mills of coarse sizes is labelled M ia The work index covering grinding of fine particles is labelled M ib Morrell 2008 M ia values are provided as a standard output from a SMC Test Morrell 2004a whilst M ib values can be determined using the data generated by a conventional Bond ball mill
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