See this useful summary Table of Bond Work Index by Minerals. For any circuit, whether a crushing circuit, a rod mill, or a closed ball mill circuit, the Work Index always means the equivalent amount of energy to reduce one ton of the ore from a very large size to 100 um. The sample was received crushed appropriately for the ball mill test.
Read OnBond models, SGI, Morrell Mi. 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 'locked-cycle' test where ground product is removed from test cycles and replaced by fresh feed. The test much achieve a steady-state before completion.
Read OnComparison of UCS to Bond Work Indices. FIGURE 8: ROD MILL/BALL MILL WORK INDEX RATIO v. UNCONFINED COMPRESSIVE STRENGTH 100 200 300 400 UCS (MPa) 0 0.5 1 1.5 2 WiRM/WiBM (metric) Siddall et al (1996) identified the ratio of Bond rod mill Work Index and ball mill Work Index as being indicative of an ore's compentency.
Read Onthe final product size. The prediction of the SAG mill transfer size used in the formula is made by comparison with pilotplant data and operating plant data for similar ore types (Barratt, 1989). The approach acknowledges grinding efficiency as the ratio of operating work index to that for a single-stage ball mill.
Read OnApr 08, 2018 The parameter Wi, known as the work index of the ore, is obtained from batch bench tests first devised by Bond (1961). The power calculated on using equation 1, (Bond, 1961; Rowland and Kjos, 1978), relates to: 1) Rod milling – a rod mill with a diameter of 2.44 meters, inside new liners, grinding wet in open circuit.
Read OnFor equation 7, if available, use either the work index from an impact test or a rod mill grindability test, which ever is higher and for equation 8, use the work index from a rod mill grindability test, since these more represent the coarse faction of the …
Read OnIt shows that the ball mill work index is normally distributed with an average of 14 6 and a median of 14 8 kWh t BOND ROD MILL GRINDABILITY The Bond Rod Mill Grindability Test is performed similarly to the ball mill test The feed sample is stage crushed to ½ and the test is run under a 100 circulating load As in ... 10 Sep 2017 Here is a ...
Read OnThe working principle of ball mill Jul 30, 2012· Autogenous (AG) and Semi-Autogenous (SAG) milling has seen increased use in recent years, especially in large mineral processing operations. These mills typically have a large diameter relative to their length, typically in …
Read Oneffects of grinding media shapes on ball mill WIReDSpace . 2 2 1 Bond 39 s theory The Bond law of grinding has been widely used for mill sizing and design The model is an empirical equation based on analysis of data from laboratory and industrial mills It is based upon the two power calculation approaches used in majority of ball and rod mill design processes Smit 2000 i e a
Read Onan average work index of 15.5 kWh/t. A very broad range of results was received, characterising the 'standard ore' from medium to very hard. A disappointing result considering the reliance on this test globally for design and optimisation. An improved method using less mass compared to the Bond Ball Mill Work Index test.
Read OnThe ability to simulate the Bond work index test also allows examination of truncated ball mill feed size distributions on the work index. For grinding circuits where the feed to a ball mill is sent directly to the classifier and the cyclone underflow feeds the ball mill (see Figure 3.10), a question arises as to whether this practice will alter the ball mill work index (BW i) of the material ...
Read On04/11/2020 Bond Ball Mill Work Index, BWi, kWh/t 13.4 Bond Rod Mill Work Index, RWi, kWh/t 18.1 Table 1. Example of AG/SAG Ball Mill Circuit Wio Calculations [1] [2] ABstrAct Optimum use of power in grinding, both in terms of grinding efficiency …
Read OnThe biggest characteristic of the sag mill is that the crushing ratio is large. The particle size of the materials to be ground is 300 ~ 400mm, sometimes even larger, and the minimum particle size of the materials to be discharged can reach 0.1 mm. The calculation shows that the crushing ratio can reach 3000 ~ 4000, while the ball mill's ...
Read Onrod mill work index has not been de ned as yet. The ball fi mill work index is con rmed at 16 kWh/t. The operating fi work index, though, is in the range of 21 kWh/t to 25 kWh/t showing high ineffi ciency. This raises the point that, in some cases, the Bond EF4 oversize factor calculation is not suf cient to compensate fi
Read OnThe Bond Ball Mill Work Index (BBWi) test is carried out in a standardised ball mill with a pre-defined media and ore charge. The Work Index calculated from the testing can be used in the design and analysis of ball mill circuits. The test requires a minimum of 10kg of sample that has been stage-crushed to passing size of <3.35 mm.
Read OnJul 30, 2020 An improved method using less mass compared to the Bond Ball Mill Work Index test. The JK Bond Ball Mill JKBBM test, is a locked cycle grindability test conducted using a standard laboratory Bond Ball Mill with the same steel ball charge and material feed size 100 passing 3.35 mm as the Bond Ball Mill Work
Read OnSag Mill And Ratio Of Bond Ball And Rod Work Index. Ball Mill DesignPower Calculation - 911 Metallurgist. 19062015 The basic parameters used in ball mill design power calculations rod mill or any tumbling mill sizing are material to be ground characteristics Bond Work Index bulk density specific density desired mill tonnage capacity DTPH operating solids …
Read OnA Bond Ball Mill Work Index may also be used in the simulation and optimisation of existing mill(s) and the associated grinding circuit(s). Sample requirements: A minimum of 8 kg of material crushed to nominally minus 10 mm is preferred. JKTech would stage crush the sample to minus 3.35 mm, as required for the Bond Ball Mill Work Index test feed.
Read OnThe mill product can either be finished size ready for processing, or an intermediate size ready for final grinding in a rod mill, ball mill or pebble mill. AG/SAG mills can accomplish the same size reduction work as two or three stages of crushing and screening, a rod mill, and some or all of the work of a ball mill.
Read OnSag Mill And Ratio Of Bond Ball And Rod Work Index. Sag Mill And Ratio Of Bond Ball And Rod Work Index Mill (grinding) - Wikipedia Deze pagina vertalen W is the work index measured in a laboratory ball mill This ball mill, also called mill for measuring bond work index, is a key device for measuring grinding work index It is widely used by teaching and researching departments for …
Read OnBond Ball Mill Grindability Test Golden Ratio. achieved similar to the Bond rod mill and ball mill The MacPherson Autogenous Grindability Test is a continuous test performed in an 18 46cm semi- autogenous mill with an Get Price P80 of Bond ball mill Work Index tests - LinkedIn. Rod Mill Design Calculation Prominer Shanghai Mining
Read OnA Method of C alculating Autogenous/ Semi. stage ball mills rod mills or AG/SAG mills when using Bond rod mill work index RMWI and Bond ball mill work …
Read OnThe Work Index is used when determining the size of the mill and grinding power required to produce the required ore throughput in a ball mill. 2. Procedure 2.1. Bond Ball Mill Grindability The sample was crushed to passing 6 mesh (3.35mm), from this a 700 cc volume was measured and weighed to be used as feed for the Bond Mill.
Read OnBall mill： Ball mills are the most widely used one. Rod mill： The rod mill has the highest efficiency when the feed size is <30mm and the discharge size is about 3mm with uniform particle size and light overcrushing phenomenon. SAG mill: When the weight of the SAG mill is more than 75%, the output is high and the energy consumption is low ...
Read OnThe standard bond rod mill work index test procedure is firstly to stage crush the feed to pass 12.7 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 0.305m by 0.610m, with wave liners (of a form described by bond), which runs at 40rpm and tilts as described below.
Read OnThe rod mill test gave RWilab of 14.5 kWht and a ball mill work index BWilab of 13.8 kwh t. Accepting that the rod mill work index applies to size reduction of the circuit feed down to the rod mill test product P80 of 1050 um and that the ball mill work index applies from this size to the circuit product size, calculate the standard Bond energy ...
Read OnBond Rod Mill. Rod Mill Design Calculations Wibm is the bond ball mill work index unitless cfnet is an empirical adjustment to a ball mill circuit cfnet 235 029 lnp80 morrell mi model morrell 2008 published a twoparameter model based on two equations 3 amp 4 to describe a variety of comminution devices including singlestage sag and ag mills the.
Read OnThe 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) conducted from a feed size of approximately 10 mm to a product size on the order of 1 mm. The Bond crushing (impact) work index (Wi C, CWi, LEIT or IWi) conducted ...
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