particle size are calculated and the Bond ball work index is then calculated using the standard Bond ball work index formula: 𝑊𝑖= 44.5 𝑃0.23·𝑔𝑏𝑝0.82·[10 √𝑃80 · 10 √𝐹80] [2] where W i represents the Bond ball work index, F 80 and P 80 …
Bond Abrasion Index (Ai) – sufficient mass to produce 4 x 400 g of charges of -19+12.7mm ore. Bond rod mill work index (RWi). Typically, 10-12 kg at the target crush size. Bond ball mill work index (BWi). Between 6 …
Learn how to perform a Bond Work Index Test or Bond Ball Mill Work Index Test to determine the grindability of ore samples. Follow the steps, equations and examples to calculate the Bond Work Index and the grindability of the ore.
Introduction. The Bond grindability test for determining the Bond work index, W i, is conducted in a Bond ball mill having the dimensions D × L = 305 × 305 mm and a speed revolution of 70 min − 1.The mill is loaded with balls from 15.5 up to 30.6 mm in diameter, having thus a total mass of 20.125 kg.. This test simulates a closed circuit of …
JK Bond Ball Mill Test Since its introduction in the 1960s, the Bond Ball Mill Work Index (BBMWi) parameter has been extensively used in predicting ball mill power draw. Use of Work Index Along with comminution circuit design the work index parameter is widely used in tracking mill performance. Due to the age and lack of controls for the test,
The 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 ...
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. Source 1 Source 2 Source 3 Source 3 Source 4 Source 5 Source 6 Source 6 KWh/t Source 6; Avg Bond Work Index: kWh/t: kWh/t: kWh/sh.t: kWh/t: kWh/t: kWh/t: kWh/t: …
The Tovarov grindability index is used to determine the influence of materials on the cement clinker grinding capacity of a mill; the basis is rotary kiln clinker with a defined grindability index of a = 1.According to …
The test determines the Bond Impact Work Index which is used with Bond's Third Theory of Comminution to calculate net power requirements when sizing crushers*. It is also used to determine the required open-side settings (jaw crushers and gyratory crushers) or closed-side settings (cone crushers) for a given product size.P80 = …
1.. IntroductionA Bond Ball Mill Work Index test is a standard test for determining the ball mill work index of a sample of ore. It was developed by Fred Bond in 1952 and modified in 1961 (JKMRC CO., 2006).This index is widely used in the mineral industry for comparing the resistance of different materials to ball milling, for estimating …
the Bond Work Index (kWh/t) can be rapidly estimated (less than 2 hours) and show a high accuracy for mills of non-standard dimensions (R2= 0.96). Keywords: Bond´s Work …
The basic work index equation is: W = 10 Wi/√P – 10 Wi/√F(1) where W is the work input required in kilowatt hours per short ton to grind from 80% passing F microns to 80% passing P microns, and Wi is the work index, or the grinding resistance parameter. It represents the energy input required in kilowatt hours to reduce a s…
The self-grinding work index is an extension of the concept of Bond work index. It generally refers to the work index calculated by using Bond's fracture theory on the principle of ore crushing energy consumption according to the W, F, and P data of a small or semi-industrial or industrial self-grinding test. In this kind of test, McPherson …
The Bond Work Index (Wi) is a common technique for the estimation of hardness and energy requirement for comminution using ball mills. However, this technique is time-consuming (close to 5 hours ...
Bond Rod Index Mill, 12" x 24" consisting of a one (1) piece cast shell complete with integral wave, 1 Hp 3/60/220 volt motor/gear reducer drive, support frame which allows the mill to tilt +/- 5 degrees during operation and 45 degrees for discharge (manual operation), receiving pan, rod charge and control panel complete with digital revolution counter, …
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 ...
Derivation of Equation According to Hukki (1962), the specific energy required, E can be expressed in a general form of differential equation (1) for the case of a limited size range where C2 is ...
When accurate mill ore feed rate in dry tons per hour, mill power draw in kilowatts, and mill feed and product size analyses in microns are available the Bond Equation can be used to measure the operation of comminution machines, reporting it as operating work index. The equation for operating work index as given in the paper …
of the Third Theory fitting of the work index formula to the rod mill apparatus. • The nature of the breakage will be skewed towards abrasion breakage in the smooth liner ... Grindability Database is plotted as rod mill work index (Bond in blue, non-standard in red) versus the A×b of a drop weight test (JK DWT or SMC Test). 0 20 40 60 …
Based on the standard procedure defined by Bond, the ball mill work index is determined by simulating a closed cycle dry grinding in a laboratory Bond ball mill until a stable circulating load of 250% is established (Bond, 1949, Bond, 1952, Bond, 1961). The ball mill work index is determined by Eq. (10). The recommendation is the ball mill ...
Josefin, Y., Doll, A.G., 2018. Correction of Bond Ball Mill Work Index Test for Closing Mesh Sizes. Procemin-Geomet 2018. 14th International Mineral Processing Conference & 5th International Seminar on Geometallurgy, …
The bond work index for a mesh-of-grind of 200 mesh for a rock consisting mainly of quartz is 17.5 kWh/ton. How much power in kW is needed to reduce the material in a wet-grinding ball mill from an 80% passing size of 1100 µm to an 80% passing size of 80 µm at a capacity of 10 ton/hr?
The Bond Work Index approach is the standard method of selecting ball mills to grind from about 3 mm to 25 µm provided that correction factors are used if …
A modified equation has been proposed to calculate the Bond Ball Grinding Index (BWI), that considers the ratio of the MSL-14K mill net grinding power to the net …
grams per revolution (Gbp) is the ball mill grindability. The ball mill work index, Wi (kWh/short ton) is calculated from the following equation (Bond 1961):1 The mill should be cleaned by either blowing air into it or wiping the interior with a cloth and or brush. The FC Bond ball mill is now ready for the next sample.
The computation of a Bond ball mill work index was empirically calibrated by Fred Bond using a short ton basis. The modern (metric tonne) basis is the following equation: Derived values composed from Wi BM results. Morrell Mib value is calculated for a sample if the following are available: umClosing, F80, P80, gpr.
Commentary on the apparatus of the Bond rod mill Work Index by Alex Doll December, 2015 alex.doll@sagmilling The Bond "Third Theory" of comminution was originally divided into three size classes reflecting the varieties of comminution equipment common during the time period when Bond (and his collaborators) were …
The grinding-product size, P, in a Bond ball mill, ... (1961), is deter- mined by the formula: / 10 10 (I) The work index is determined by grinding experiments carried out in a labo- ratory Bond ball mill. Based on the results of grinding experiments, numerical values of the work index Wi are calculated according to the formula: 0301-7516/89 ...
Learn about the Bond work index, a parameter to measure ore hardness based on Bond's law of energy consumption. Find chapters and articles on comminution, Bond tests, and …
Differences up to 6,2% in the Bond ball mil work index can be observed due to different siz distribution in P 80 calculation.. 13 ores were tested using the Bond ball mill grindability test, obtaining P 80 using different interpolation functions. Rosin Rammler's model showed the best behavior, so its use must be not only suggested, but …
A standard Bond mill (Fig. 1) was designed to perform the work index tests and determine the energy consumption of various s minerals.The mill has a round internal housing at the corners, has no lifters, and is for dry grinding. The inner diameter and the length are 0.305 m, and the ball load is 19.4% of mill volume (equaling a total weight of …
The grinding-product size, P, in a Bond ball mill, which is given by the aperture size which passes 80% of the grinding product as a function of the aperture size of the test screen Pk, can be ...
Mill diameter; Mineral density; Work Index. Bond estimated the amount of wear in terms of kilograms per kWh based on the abrasion index, A;, i.e., Wet Ball Mill = kg kWh = 0.16(A i-0.015) 0.33; Dry Ball Mill = kg / kWh = 0.023A i 0.5; Replacement Ball Size
Fig. 1. Ores for the work index test: a) type and b) feed size 2.2. Ball mills and operation conditions Fig. 2(a-d) shows the ball mills used in the determination of the Work Index (standard mill BBM and non-standard mills BM-1 to BM-3, all ball mills without lifters). Bond standard ball mill (Fig 2(a);