2017-1-7 The 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 100% 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 More2018-12-7 The goal of this work is to create an equation to adjust a Bond ball mill work index from one P 80 basis to another. The proposed model consists of two components, the variable coefficient that is determined from a specific work index determination and a fixed exponent determined by a
Read MoreThe 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 More2017-7-9 In this regard calculation of work index of limestone made by standard Bond grindability test. Ball mill was employed to conduct the grinding test of seven different samples. Among all seven samples collected from the different faces of quarry, Bond work index of limestone Face4A results less than 20kwh/t, remaining 6 samples are marked as hard -
Read MoreThe Bond ball mill grindability test is run in a laboratory until a circulating load of 250% is developed. It provides the Bond Ball Mill Work Index which expresses the resistance of material to ...
Read More1989-1-1 The Bond work index, W i, as an indicator of the grindability of raw materials is not a material constant but rather it changes with change of size of the grinding product.Therefore, in practice we can expect some difficulties and errors when the energy consumption is determined according to this formula in the case when, for a given size of grinding product, the value of the work index W i ...
Read More2020-9-24 Where, WioACTis the Actual Operating Bond Work Index (kWh/t), W is the specific energy input (kWh/t), P80 is the 80% passing size of product (µm), and F80 is the 80% passing size of circuit feed (µm). 2. Calculate the Standard Circuit Bond Work Index (WiSTD) for the material being processed (equation 3). Wtotal
Read More2014-6-27 The Bond's standard ball mill is used to determine the work index value of differ ent samples. The Bond work index is defined as the kilowatt-hours per short ton required to break from infinite size to a product size of 80% passing 100 µm. If the breakage
Read More2015-6-19 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,
Read More2020-3-19 Bond Ball Mill Work Index. GTEK Bond Ball Mill Work Index is used for determine the grindability of materials, and help to choose the most suitable type and model of grinding equipment. Ask For Quote Donwload. Find more details in the options below. Photo.
Read MoreThe Bond ball mill grindability test is run in a laboratory until a circulating load of 250% is developed. It provides the Bond Ball Mill Work Index which expresses the resistance of material to ...
Read More2020-9-24 Where, WioACTis the Actual Operating Bond Work Index (kWh/t), W is the specific energy input (kWh/t), P80 is the 80% passing size of product (µm), and F80 is the 80% passing size of circuit feed (µm). 2. Calculate the Standard Circuit Bond Work Index (WiSTD) for the material being processed (equation 3). Wtotal
Read More2014-6-27 The Bond's standard ball mill is used to determine the work index value of differ ent samples. The Bond work index is defined as the kilowatt-hours per short ton required to break from infinite size to a product size of 80% passing 100 µm. If the breakage
Read MoreAn alternative mill ball charge is proposed that closely approximates Bond's original total ball mass, number of balls and ball surface area. Results of 30 Bond Work index tests of six pure ...
Read MoreBond ball mill work index: Figure 2: Ball mill for determining Bond ball mill work index 1 For the purists, there were two models in existence at the time: the Von Rittinger and Kick models. Neither of these gave results that matched the observations of specific energy consumption from tumbling mills.
Read More2021-11-30 Only relatively small quantities of sample are required and can be re-used to conduct Bond ball work index tests. The results from conducting the SMC Test® are used to determine the so-called drop-weight index (DWi) which is a measure of the strength of the rock as well as the comminution indices Mia, Mih and Mic.
Read More2018-2-20 Bond Test WI’s (kWh/t): Rod Mill: Ball Mill: 9.5 kWh/t.8 9 kWh/t . Bond Standard Circuit Work Index: Assume the rod mill Work Index of 9.5 applies from the actual rod mill feed sizeof 19,300 mµ (although some of this work might ideally be done by crushers to achieve a
Read More2014-10-1 submitted to the Bond ball mill work index test. The number of SAG mill revolutions required to grind the material to a P 80 of 1.7 mm is used to predict AG/SAG specific energy using quation 4. Correction E factors for feed size and pebble ing are applied to
Read More2020-12-4 The laboratory procedure for running a Bond ball mill work index test requires that the operator choose a closing screen sieve size. The instruction is to choose a sieve size that results in the ...
Read More2021-2-24 21 CONCLUSIONS Continued In the present work, equations were also derived, giving: zthe ball-mill power drawP as a function of its dimensions: internal mill diameter D and length L, zthe ball-mill power drawP as a function of the feed D f (mm) and the product size d (mm), the Bond work index w i (kWh/short ton) and the mill throughput T (short ton/h), zthe ball-mill dimensions (D and L), when ...
Read MoreBond ball mill work index: Figure 2: Ball mill for determining Bond ball mill work index 1 For the purists, there were two models in existence at the time: the Von Rittinger and Kick models. Neither of these gave results that matched the observations of specific energy consumption from tumbling mills.
Read More2018-2-20 Mill Ball Mill Closed circuit crushing to 16 mm Open circuit 8’ dia. rod mill to 1 mm Closed circuit 8’ dia. ball mill to P80 um The ore Test Work Index = Circuit Operating Work Index 9 The Standard Bond Circuit Coarse Ore Bins Fine Ore Bins Screen Crushing Screen Classification Rod Mill Ball Mill THIS IS THE REFERENCE BASIS FOR ALL WORK ...
Read MoreThe Bond ball mill grindability test is run in a laboratory until a circulating load of 250% is developed. It provides the Bond Ball Mill Work Index which expresses the resistance of material to ...
Read More2020-3-30 The Bond Work Index for Ball Mill is a special equipment for testing Bond ball mill work index. Simple lab test can choose ball mill by power method or judge the effects of material properties change to the ball milling process or the operation condition of crusher by using this equipment. From 1980s, the company developed the equipment and ...
Read MoreNumerically, the work index is the energy required in kwh/t to reduce a given material from theoretically infinite feed size to 80% passing 100 microns. The work index of a particular material is determined in the laboratory by conducting the standard Bond grindability test. Bond developed separate tests for the rod mill and the ball mill.
Read More2016-12-27 micrometers in size. According to the Bond standard procedure, the work index is determined by simulating a dry grinding in a closed circuit in the Bond ball mill to achieve 250% circulating load (Bond, 1949, 1952, 1961). The test is performed on a raw material approximately weighing 10 kg, which coarseness is 100% -3.327 mm.
Read MoreThe Bond Index conforming rod charge consists of: 6 rods of 1.25“ diameter and 21“ length. 2 rods of 1.75“ diameter and 21“ length. The grinding jar for the Bond Index Rod Mill is 12″ x 24″ in size and has a wave-shaped design. At least 15 to 20 kg sample material is required to simulate a closed grinding circuit in a ball or rod mill.
Read More1998-11-1 Rowland, C.A., 1978, “Determination and use of operating work indices in controlled grinding circuits–A proposed concept,” Mill Operator’s Conference and Exhibit, Northwestern Branch, Australasian Institution of Mining and Metallurgy, Mt. Isa, Queensland Australia, June.
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