Determining the Bond index using the Fred Bond method [1,2] is considered the state-of-the-art methodology for mill calculations and a critical process parameter in raw materials selection and grinding process control.Although it is usually referred to as a standard test, no ISO (International Organization for Standardization) or ASTM (American …
Đọc thêm
To determine the actual mill power draw and volumetric load of your mill from plant readings and measurements. 4. Work Index Efficiency To determine the Work Index calculations for evaluating grinding circuit efficiency, as initially developed by Mr. Fred Bond. 5. Functional Performance of Ball Milling To determine ball mill circuit …
Đọc thêm
The basic parameters used in ball mill design (power calculations), rod mill or any tumbling mill sizing are; material to be …
Đọc thêm
Many power-based grinding models exist, and most operators are familiar with Fred Bond's "third theory". Bond's model is most commonly used to describe primary and secondary …
Đọc thêm
E = K (P80 ⁿ – F80 ⁿ ) where K and n are empirical constants measured for your ore. One solution for this equation Bond's equation if K = (10·Wi) and n = –½. 1. Reference ore. Run a ...
Đọc thêm
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 expressed by the formula P= P k K 2. These functions for G and P enable us to calculate the value of Wi for any other size of grinding product if we know ...
Đọc thêm
capacity ball mills were installed from the late 1970s (5.5 m diameter and larger) it was found that throughput predictions for large mills with high feed rates of coarser particles were greater than those achieved. Correction factors based on the new data were required. SAG mill-ball mill circuits using large diameter mills
Đọc thêm
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 expressed by the formula P=Pk/K2. These functions for G and P enable us to calculate the value of Wi for any other size of grinding product if we know ...
Đọc thêm
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 … See more
Đọc thêm
2.2.1. Bond Ball Mill Standard Test The procedure to carry out the Bond grindability test [1,18] is described below. The test is performed in the so-called Bond's standard ball mill, a laboratory mill 1200 1200, running at 70 rpm (BICO, San Francisco, CA, USA) with rounded inner edges and without lifters.
Đọc thêm
The Bond's Equation is commonly used to predict the size-reduction energy in tumbling mills. The calculation of the Bond Equation requires the Bond Index, which …
Đọc thêm
size reduction equipment power and circuit tonnage (equation 1). Auxiliary equipment power is excluded. P W = ––– (1) T Where, W is the specific work input (kWh/t), P is the …
Đọc thêm
The rod mill motor power is in horsepower at the mill pinion-shaft. For different length rod mills power varies directly as rod length. For difference between new and worn liners increase power draw by 6%, …
Đọc thêm
In Hukki's example, Bond's equation with exponent of -½ fits grinding to the 1 mm size range, roughly the product size expected from a rod mill. The exponent in ball mill size range, around 100 µm, is close to -1, the exponent predicted by Von Rittinger's model. This is only one result (Hukki acknowledges
Đọc thêm
The 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 …
Đọc thêm
of two or more grate discharge ball mills in series. The same equation is used to calculate the power that each ball mill compartment should draw. The total power is the sum of the power calculated for each of the separate compartments. Although, Bond's method has been widely used, the required link to classification is missing.
Đọc thêm
the form of Equation (3). The Jar Mill test favoured by gives a table of results of E and measured size x for a progressive batch grinding test; these results can be fitted as demonstrated in Figure 4. A series of Bond ball mill work index tests run at different closing mesh sizes can be fitted in almost the same way.
Đọc thêm
The ball to charge ratio may be 5:1, 10:1, 15:1. This method is more efficient in achieving fine particle size. Rod mills: Horizontal rods are used instead of balls to grind. Granularity of the discharge material is 40-10 mm. The mill speed varies from 12 to 30 rpm. Planetary mill: High energy mill widely used for producing metal, alloy, and ...
Đọc thêm
The Bond ball mill grindability test is one of the most common metrics used in the mining industry f or or e har... [↓ read more ↓] Alex Doll, Vladimir Nikolić: static image: Example test database plot [] Example database chart for the Subscriber Tools page...
Đọc thêm
The failure of these rod mill and ball mill bench-mark studies to validate either model led to the development of a "Third Theory" by Fred Bond Bond 1952. ... the mill power draw models are independent of the ore being processed (ore density matters, but feed and product sizes should not affect power draw if the mill is run properly). ...
Đọc thêm
Many power-based grinding models exist, and most operators are familiar with Fred Bond's "third theory". Bond's model is most commonly used to describe primary and secondary grinding to product ...
Đọc thêm
The Work Index (BWi) is calculated according to Fred Bond's Equation. Bond Work Index for Testing Procedure. Cleaning and Storing of Ball Mill Charge after the Bond Work Index Procedure is done: Add about 500 g of silica sand into the mill containing the ball charge. Seal the mill. Rotate for 20 revolutions to clean. Empty the …
Đọc thêm
The Bond Equation as found in reference 5 is: W = 10Wi/p0.5 – 10Wi/p0.5. Where: W = kwh per short ton. Wi = Work Index determined from crushing and grinding tests. P = The size in microns (micrometers) that 80% of the product is finer than. F = The size in microns (micrometers) that 80% of the feed is finer than.
Đọc thêm
Bond mill power equation T15:03:05+00:00 Who we are > Products > Cases > Solutions > Contact Us > Solutions. Copper ore beneficiation plant; Iron Ore Beneficiation Plant; Iron ore powder beneficiation production sand …
Đọc thêm
The "effective mill power" (EMP) can then be defined relative to the total mill power (TMP). EMP is the per-centage of total mill power draw delivered to the "coarse" ore and is defined as EMP = TMP x CSEff (1) The ball mill circuit functional performance equation. A practical measure of a given circuit's productivity (as
Đọc thêm
The proposed model, combined with a model giving the ball-mill power draw, is used for the ball-mill scale up. Comparisons with the Bond procedure showed a good agreement for the prediction of the ...
Đọc thêm
energy in ball mills for which the Bond equation was originally designed. 3.1 The standard Bond grindability test . ... revolutions per minute which equates to a mill power draw of 111.1 W.
Đọc thêm
This is a material transport problem and in the case of grinding mills it is usually sufficient to assume that if the machine can draw the required power it can also process the required ...
Đọc thêm
Total SAG Motor Power = (ESAG × tonnes/hour) ÷ 0.985 ÷ 0.90 (9) The ball mill motor can be sized using a similar equation, but ball mills normally operate at a higher proportion. of their rated power output, use 0.94. The ball mill gear/pinion efficiency is the same as for a SAG mill. For a.
Đọc thêm
In a review for a ASM publication, Morrell (in Anderson et al., 2014) notes that Bond's contribution and what made his equation so successful is that he combined it with a series of associated laboratory …
Đọc thêm