Use of the Bond Work Index to size industrial grinding equipment was widely known. Bond also described its application for measuring grinding circuit efficiency. Bond Work Index efficiency has been widely used by industry, but until now without concise standard methods, or a formal guideline, for doing so. The Bond Efficiency SubCommittee of -

2|DETERMINING THE BOND EFFICIENCY OF INDUSTRIAL GRINDING CIRCUITS Calculations: 1. Calculate the Actual Operating Bond Work Index of the grinding circuit. • Estimate the F80 and P80. • Calculate the work or specific energy input from the size reduction equipment power and circuit tonnage (equation 1). Auxiliary equipment power is excluded. P

Although widely known as a tool for sizing and selection of crushing and grinding equipment, use of the Bond Work Index Equation as a tool to measure grinding efficiency is less widely known and used.

Sizing a crusher can be done reliably calculated thanks to the Impact/Crushing Work Index and the testwork research done by Fred Chester Bond and his 1952 paper. According to Bond’s Third Theory of Comminution, the work/energy input is proportional to the new crack tip length created during particle breakage and equivalent to the work represented by the product – the feed. A crude test ...

The work Index Wi as previously determined at any specified 80% passing product size is still the most practical criterion of the actual work input required for reduction to near that size. Measurement of the exposure ratios of feed and product can increase the accuracy of work …

Sizing a crusher can be done reliably calculated thanks to the Impact/Crushing Work Index and the testwork research done by Fred Chester Bond and his 1952 paper. According to Bond’s Third Theory of Comminution, the work/energy input is proportional to the new crack tip length created during particle breakage and equivalent to the work represented by the product – the feed. A crude test ...

Although widely known as a tool for sizing and selection of crushing and grinding equipment, use of the Bond Work Index Equation as a tool to measure grinding efficiency is less widely known and used. Bond specified the specific energy (W, in kWh/t) that should be needed, that is for circuit design, based on average plant performance of his day ...

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.

the work index depending on the grind size. In this way, work index values are usually obtained for some specific grind size that characterizes the grinding operation to design or under evaluation. This study was carried out in a standard bond ball mill 305 mm x 305 mm size

The Bond work index is a measure of ore resistance to crushing and grinding and is determined using the Bond grindability test. Its value constitutes ore characteristic and is used for industrial ...

[2], the operating work index (Wio) of an existing grinding circuit can be calculated, given known mill power draw, throughput, feed and product size distributions. kWh/t = Power applied per ton of feed to the grinding unit Wi = The standard Bond work index of the ore P 80 = The 80% cumulative passing size of the product in microns F 80

Metallurgical ContentSizing a Ball or Rod Mill Sizing a Crusher using >1200 Wi of Ores from DatabaseHow to Find the Work Index (Wi)How to Find the Work Input (W)How to Correct Calculated Work Indexes for Unnatural FeedsHow to Find Impact Crushing Strength From the Work IndexHow to Find Work Index From Closed Circuit Grindability TestsHow to Find Work Index From Open Circuit …

Oct 15, 2015· The Bond Work Index (BWI or W i) is defined as the calculated specific energy (kW h/t) applied in reducing material of infinite particle size to 80% passing 100 μm . The higher the value for W i , the more energy is required to grind a material in a ball mill [10] , [26] .

* Bond F. C., “Crushing & Grinding Calculations”, Reprint from British Chemical Engineering, Allis-Chalmers Publication 07R9235B. Bond Low Energy Impact Test. 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*.

Dec 12, 2016· 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 ¼ inch (6350 microns).

In the present work, equations were derived, giving the specific grinding energy w as a function of: zthe feed D f (mm) and product size d (mm) (both 80% cumulative passing) and the Bond work index w i (kWh/short ton) or, zas a function of the size reduction ratio R = D f /d, of the Bond work index w i and the product size d,

particle to such a size that 80% of the product will pass through a 10micrometer, or 0.1 mm screen. •If Dp is in mm, 𝑊𝑖=𝐾 1 𝐷𝑝𝑝 𝐾 = 0.1𝑊𝑖=0.3162𝑊𝑖 I =0.3162𝑊𝑖 1 𝑝𝑝 − 1 𝑝 •Values of WI for wet Grinding: Property Soft Medium Hard Very hard Work Index,𝑊𝑖, KWh/ton 7-9 9-14 14-20 >20

Wi – Work index . Gross energy requirement in kilowatt-hour per tonne of feed needed to reduce a very large feed to such a size that 80% of the product passes through a 100 micro meter screen • An ideal size reduction equipment should fulfill the following conditions – Large capacity

the work index depending on the grind size. In this way, work index values are usually obtained for some specific grind size that characterizes the grinding operation to design or under evaluation. This study was carried out in a standard bond ball mill 305 mm x 305 mm size

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.

[2], the operating work index (Wio) of an existing grinding circuit can be calculated, given known mill power draw, throughput, feed and product size distributions. kWh/t = Power applied per ton of feed to the grinding unit Wi = The standard Bond work index of the ore P 80 = The 80% cumulative passing size of the product in microns F 80

Oct 19, 2017· The enterprises consumers grinding media have a question about right choise the grinding ball size (diameter) for the mill in order to achieve the required grinding quality. We noted earlier, this information can be obtained from several sources: — Technical documentation. It attached to the milling equipment (mill).

Oct 15, 2015· The Bond Work Index (BWI or W i) is defined as the calculated specific energy (kW h/t) applied in reducing material of infinite particle size to 80% passing 100 μm . The higher the value for W i , the more energy is required to grind a material in a ball mill [10] , [26] .

Sep 17, 2020· “Crushing and Grinding Calculations,” by Bond, F. C., 1961-62, reprinted from British Chemical Engineering by Allis-Chalmers Industrial Press Department This is the premier Bond Work Index equation application manual. Bond presents use of his breakthrough formula relating comminution circuit feed size (F80), circuit product size (P80) and the ore Work Index to industrial equipment …

Wi – Work index . Gross energy requirement in kilowatt-hour per tonne of feed needed to reduce a very large feed to such a size that 80% of the product passes through a 100 micro meter screen • An ideal size reduction equipment should fulfill the following conditions – Large capacity

available was the Bond work index, which was calculated with insufﬁcient ore comminution characteristics testing and semi-industrial testing [3–5]. This was due to the lack of research in this ﬁeld in China and the lack of knowledge in SABC circuit design. The sizing of the processing equipment

particle to such a size that 80% of the product will pass through a 10micrometer, or 0.1 mm screen. •If Dp is in mm, 𝑊𝑖=𝐾 1 𝐷𝑝𝑝 𝐾 = 0.1𝑊𝑖=0.3162𝑊𝑖 I =0.3162𝑊𝑖 1 𝑝𝑝 − 1 𝑝 •Values of WI for wet Grinding: Property Soft Medium Hard Very hard Work Index,𝑊𝑖, KWh/ton 7-9 9-14 14-20 >20

The work index covering grinding in tumbling mills of coarse sizes is labelled M. ia. The work index covering grinding of fine particles is labelled M. ib (Morrell, 2008). M. ia. values are provided as a standard output from a SMC Test ® (Morrell, 2004. a) whilst M. ib. values can be determined using the data generated by a conventional Bond ...

Bond Work Index an overview ScienceDirect Topics. The Bond work index is not solely a material constant but is influenced by the grinding conditions For example, the finer the grind size desired, the higher is the kWh/t required to grind to that size Magdalinovic [38] measured the Bond work index of three ore types using different test screen sizes He produced a correlation between the mass of ...

ground using the laboratory ball mill grinding machine. 80% passing size for the iron ore marble and granite samples were obtained at 100μm sieve size for the feeds and products. The work index of reference minerals; marble and granite were used to calculate the work index of iron ore.

Two Types Of Grinding Machines Free Essay Sample. the power predictions for ball mills typically use the following form of the bond equation: here is the energy Wi is the work index measured in a laboratory ball mill is the mill circuit product size in micrometers is the mill ball mill principle attrition mill for mining. ball mining process Of attrition grinding mill china ball mining process ...

delineating size between coarse and fine grinding is 750 µm. SMC test results are used to determine the Drop Weight Index (DWi) and the coarse ore grinding index (M ia). Test data from the Bond ball mill work index test is used to calculate the fine grinding index (M ib). The M ia and M ib indices are used to calculate specific energy for the ...