Numerically, 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.
Calculating crushing constant using bonds law bond work index formula-equationee this useful summary table of bond work index by mineralsor 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 bond s law for crushing mills -.
The 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.
Calculating Crushing Constant Using Bond S Law. Calculating crushing constant using bonds law bond work index formula-equationee this useful summary table of bond work index by mineralsor 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 bond s law for crushing mills -.
Mill Type Overview. Three types of mill design are common. The Overflow Discharge mill is best suited for fine grinding to 75 – 106 microns.; The Diaphram or Grate Discharge mill keeps coarse particles within the mill for additional grinding and typically used for grinds to 150 – 250 microns.; The Center-Periphery Discharge mill has feed reporting from both ends and the product discharges ...
However, if the sample is to be prepared by cutting with a diamond saw (cut-core method) as little as 5kg is normally sufficient. Also remember that the products from the SMC Test® can be re-used for Bond ball work index testing, the SMC Test® being effectively used as a feed preparation step for the Bond ball work index test.
A Bond Work index mill ball charge and closing screen product size distributions for grinding crystalline grains Int. J. Miner. Process., 165 ( 2017 ), pp. 8 - 14, 10.1016/j.minpro.2017.05.011
has to supply this energy and it has a different (higher) work index than the crusher (ie the ball mill is less energy efficient than a crusher and has to input more energy to do the same amount of size reduction). Hence from equation 7, to crush to the ball mill circuit feed size (x. 2) in open circuit requires specific energy equivalent to:
A 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 10 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.
The rod mill oversize feed factor (EF 4 RM) in the Barratt E SAG equation is calculated using the greater of the sample's rod mill or crushing work index. The optimal feed size and EF 4 are both calculated using whichever is greater. The ball mill oversize feed factor (EF 4 BM) is always calculated with the
Crushing of coal and calculation of size reduction efficiency. Feb 25, 2015· Feb 25, 2015· Bond Work Index 𝑤 = 10𝑊𝑖 1 𝑝 − 1 𝑓 W = Power required in KWH to crush 1 short tonne ( 2000 pound) of material Wi is the work index of the material p is the 80 % passing size of the product f is the 80 % passing size of the feed 2/25/2015 6:58:05 AM 23 24.
The 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.
Bond F C 1962 Crushing And Grinding Calculations. Bond ball mill calculations spreadsheet devalklier bond ball mill calculations spreadsheet n grinding, selecting calculate the correct or optimum ball size that allows for the best and optimumideal or target grind size to be achieved by your ball mill is an important thing for a mineral processing engineer aka metallurgist to do.
Ball Mill Design Calculation Pdf. Ball mill designpower calculation 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.
The ball mill work index laboratory test is conducted by grinding an ore sample prepared to passing 3.36 mm (6 mesh) to product size in the range of 45-150 µm (325-100 mesh), thus determining the ball mill work index (Wi B or BWi). The work index calculations across a narrow size range are conducted using the appropriate laboratory work ...
Test design Slide 14 Variation of Bond work index with circulating load. C.L. = 250%  Variation of Bond work index with circulating load. C.L. = 400% 15. Slide 15 Conclusions There are two strategy based on the change of feed rate or added water to classifier.
EF5BM=[ P80+10.3 1.145×P80] ( 3 ) The EF4 formula requires both the rod mill and ball mill work index (rod mill Wi is used to calculate the optimal feed size) and because this is a "single-stage ball mill" calculation, the F80 is actually the rod mill feed size (10,000 µm) from Table 1 and the P80 is the ball mill circuit product. The EF5 factor only applies below 75 µm to ball
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 …
two. Results of Bond ball mill tests conducted with closing screens of 75 µm or finer are to be treated with caution. The Bond Work Index relationship has been noted to apply down to approximately 70 m, and perhaps no finerµ, without making qualifications. Calculations: First, calculate the actual Operating Work Index, WloACT-, of the
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). These indexes are readily obtained using the special-purpose laboratory equipment (Fig. 1). Finding the total specific energy consumption
torque mill test is the mill energy input divided by the solids load. The energy specific cumulative grinding rate at each screen size is calculated from a torque-mill test as in the example that follows. Torque mill solids load during test: 11.25 kg (24.8 lb) of ball mill feed sample from plant survey. Sample is reconstituted with water to be
The aim of this study was to develop a new method for assessing the Bond work index in a ball mill (BBWI), which is based on a first order kinetics present in the Bond ball mill for grinding mineral raw materials (Austin et al., 1981; Ahmadi and Shahsavari, 2009). Theoretical basis of quick procedure
Ball Mill Costing Calculation. Prompt : Caesar is a famous mining equipment manufacturer well-known both at home and abroad, major in producing stone crushing equipment, mineral separation equipment, limestone grinding equipment, etc. ball mill design calculator Description : Bond Ball Mill Index – JKTech A Bond Ball Mill Work Index test may ...
bond 26 2339 3 s rod mill for work index. 19.0 MINERAL RESOURCE AND …. Table 18.3: Bond Crushing work index Results . power calculation of impact coal crusher based on bond work ...
heat balance wet ball mill in ball mill . ball mill heat calculation zacarafarm. Ball Mill Power Calculation Example 1 A wet grinding ball mill in closed circuit is to be fed 100 TPH of a material with a work index of 15 and a size distribution of 80% passing inch (6350 microns).
involve grinding). With Lloyd's ball milling book having sold over 2000 copies, there are probably over 1000 home built ball mills operating in just America alone. This article borrows from Lloyd's research, which was obtained from the commercial ball milling industry, and explains some of the key design criteria for making your own ball mill.
grinding circuits (crush-rod-ball mill or crush-ball mill). By the 1970s, the application of conventional circuits tended to be li mited to relatively low capacities.
Bond/Barratt Specific Energy Consumption SABC Model. This is a SAG or AG mill plus ball mill model that estimates the overall circuit specific energy consumption using the classical Bond work index equation for multi-stage crushing and single-stage ball milling (E ssbm) including Rowland efficiency factors.The circuit E total is equal to the E ssbm plus an inefficiency factor (CF) related to ...
Kinetic grinding test approach to estimate the ball mill work index BOND F.C., 1961, Crushing and Grinding Calculation, British Chemical Engineering 6 (June Read more. the Concentrating Process Britannia Mine Museum. In the rock, chemical and physical bonds hold the valuable minerals to crusher. In many mines, including Britannia . Get Price
The 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.
Mib Fine material (< 750 µm) work index in tumbling mill circuit(s) (kWh/t) Mic Ore work index in crusher circuits (kWh/t) Mih Ore work index in HPGR circuits (kWh/t) P100 passing size or closing screen aperture (µm) P80 80% passing size of the circuit product (µm) SABC Semi-Autogenous-Ball-Milling-Crushing SAG Semi-Autogenous Grinding
bond work index uses in gold processing - crusher in India. bond crushing work index of copper slag ... Values of Bond crushing work index will vary from a 8 kWh/t for laterite hardcap through to 22 kWh/t for banded iron ...
work inde for iron ball mill crusher manufacturers quotes. Ball Mills Mineral Processing Metallurgy. ensp· enspIn all ore dressing and milling Operations including flotation cyanidation gravity concentration and amalgamation the Working Principle is to crush and grind often with rob mill ball mills the ore in …