Low Energy Impact Crushing Work Index

Bond Impact Crushing Work Index Testing Machine

The Pendulum Tester / Bond Impact Crushing Work Index Tester. Working principle Crushing by impact. 76 mm maximum feed size. Test repetition: At least 10, preferably 20 test runs. ... This mode of breakage is similar to that occurring in a primary gyratory crusher where power rates (energy input per tonne of feed) are low (approximately 0.1 KWH ...

Bond Work Index Formula-Equation

The work index Wi can be determined from plant operations and from laboratory ball mill grindability, rod mill grindability, and impact crushing tests. The laboratory test results are used to check the efficiency of commercial operations and to compute the proper machine sizes for new installations.

Using Rock Geomechanical Characteristics to Estimate Bond …

The Bond low-energy impact test, also named impact work index or Bond impact crushing work index, can measure the crushing work index (CWI) and describes …

Bond Work Index Formula-Equation

Crushing work index Calculation

The Bond crushing work index test (sometimes called the "impact work index" test) is noisy, and the difference you observed is perfectly reasonable. The paper by Angove & Dunne (1997) reports a standard deviation in crushing work index tests across laboratories as 4.5.

Energy considerations in compressive and impact crushing …

The operating work index is constant in the energy equations (1), (2), (3) computed in a real application where particle size distribution, tonnage, and energy consumption are known. ... If it is so that impact or compressive crushing is a more energy efficient method than grinding, it will be tempting to reduce the size as much as possible in ...

Bond ≠ Ball

The Low-energy Impact Crushing work index is another Bond work index, applicable to the size range of crushing (very roughly: from 100 mm to 20 mm).

Power-based modelling of single-stage AG and SAG mill …

This parameter also goes by the acronym LEIT (Low Energy Impact Test). Results derived from drop-weight tests (could be a JK DWT™, SMC Test™ or a generic drop- ... WiC is the Bond crushing work index, unitless P80 is the SAG hydrocyclone overflow 80% passing size, µm F80 is the milling circuit feed 80% passing size, µm,

Crushing in Mineral Processing

The Bond' Crushing Work Index is common to calculate the power needed to crush rocks from a given F80 size to a resulted P80 product size. Bond's impact method comes from a double mirrored pendulum impact crusher test …

Impact work index prediction from continuum damage model …

Bond (1947) defined the impact energy per unit of thickness C B by dividing the impact energy by the thickness of each particle w, so that (1) C B = 117 (1-cos ϕ) / w where ϕ is the angle, w is given in mm and C B in J/mm. From this and the material specific gravity ρ s (in g/cm 3) Bond proposed to estimate the crushing work index using the empirical relationship …

SAG mills selection methods. III. The F. Bond index calculation (crushing)

The crushing work index (CWi) is an indicator characterizing the energy amount (kW * h / t) needed to destroy single pieces of material with a relatively large size range (-75 + 50mm). The impact on such material generally is provided by using impact energy (crushing process), that is formed by collision of two oncoming pendulums.

The Importance of Work Index in Mineral Processing

The kilowatt-hours per tone (kWh/t) will work out your work index. The number of kittowatts consumed in a hour divided by the tonnes of rock gives you your work index. Remember, the higher the Work Index the more work required to crush the rock. This will impact the equipment chosen for your project.

Comparison of UCS to Bond Work Indices

It is counterintuitive for a rock with a high UCS to have a low crushing Work Index. Therefore this result is considered unreliable and use of UCS to estimate Wi C is not recommended for this mine. 0 5 10 15 20 25 30 35 40 ... role in determining the total grinding energy required to fracture rocks inside of tumbling mills. The

impact crushing work index

The Bond LowEnergy Impact test can be used to determine the Crusher Work index (CWi), also known as the Impact Work Index The test determines the impact energy at which a specimen fails and allows approximation of net power requirements for sizing crushers The open and closed sized settings for given product sizes can also be determined index ...

A Statistical Comparison of Bond Ball Mill Grindability Work Index

The Bond low energy impact (crushing) work index test is specified to be performed on rock specimens between 50 mm and 75 mm in effective diameter. NQ-diameter drill core, frequently used in ...

Crushing Work Index and UCS

Not a great relationship, R² is less than 1/3. Changing the regression from linear to non-linear options doesn't help much. Drilling down, partitioning the data sources

GeolabsGlobal | South Africa | Comminution

The Bond Low-Energy Impact Crushing Work Index uses Bond's Third Theory of Comminution to determine the power requirements when calculating the sizing and open-side setting for rock crushers: jaw, cone, and gyratory. Sample Requirements: 20 particles in the range of …

Bond Crushing Law and Work Index Calculator …

Work Index. Work Index (𝑊 𝑖 ) is a parameter used to quantify the gross energy required in kilowatt hours per ton of feed needed to reduce a very large feed to such a size that 80% of the crushed product is finer than a 100 microns size. It is derived from Bond's Law, which relates the energy required for comminution (crushing and ...

BOND'S WORK INDEX: WHAT IT IS AND WHAT IT ISN'T

For the purposes of this paper, it is useful to classify three types of work indices: 1. A grindability measurement made in a laboratory work index apparatus, such as a ball mill work index …

Bond Impact Crushing Work Index -Procedure and Table of …

Correlation of crushing work index and drop-weight index.

Ore hardness can be estimated using commercially available standard techniques such as the SAG Power Index (SPI), Bond Work Index (BWI), and JK Drop Weight (JKDW) tests (Bailey et al., 2009 ...

Effect of Core Diameter on the Bond Impact Crushing Work Index …

The Bond low energy impact (crushing) work index test is specified to be performed on rock specimens between 50 mm and 75 mm in effective diameter. NQ-diameter drill core, frequently used in mineral exploration programs does not meet that specification, it being 45 mm diameter or less. This paper reports the effect of performing the impact test on contiguous …

Crushing Work Index for PQ Core sample

I've worked on a lot of projects where we used the cut whole-diameter PQ core for the Bond low-energy impact crushing test. One instance where the core was crushed instead of loaded into the test resulted in quite different values (lower results than whole-diameter) which we interpreted as the crushing pre-stressing the rock creating fractures.

Impact of HPGR operational pressing force and material …

It can be concluded that for this type of material, the moisture content has insignificantly higher potential influence on decreasing of Bond work index, than F value. Both used variables, however, have positive effect on decreasing the W i index and thus, potential energy savings in downstream crushing and grinding stages of technological circuit.

A public Database of tumbling mill grindability …

The `wic` (crushing work index or low energy impact work index) table includes the following fields: • # Specimens – The quantity of specimens tested for a particular sample. • WiC – The mean crushing work index of a set of specimens, metric units. • WiC Min – The minimum crushing work index of a set of specimens, metric units.

The five types of Work Index

Ball mill work index. ... Crushing work index. The Bond low-energy impact crushing work index goes by the abbreviates CWi, LEIT, and Wi_C. Specified conditions are here: https://gmggroup ...

Relationship between A*b and Bond impact work …

Also, values of crushing work index (CWi) increased inversely with the A*b breakage index, as commonly observed (Napier-Munn et al., 1996; Tavares and Silveira, 2008). In order to demonstrate the ...

impact crushing work index

Bond Work Index Tests Grinding Solutions offers a range of Bond Work Index Testing from crushability and abrasion to ball and rod mills For more information on the tests please see below: Bond Low Energy Impact Test The Bond LowEnergy Impact test can be used to determine the Crusher Work index (CWi), also known as the Impact Work IndexIMPACT ...

Model:Bond/Barratt SABC Models

Bond crushing (low-energy impact) work index; Required parameters. F 80, µm is the 80% passing size of the fresh feed to the circuit (expected to be a Bond-compatible size distribution). P 80, µm is the 80% passing size of the circuit product (expected to be …

Testwork: Bond crushing work index

There is a high-energy impact work index which is a different (and incompatible) test. The high-energy test has fallen into disuse and any recent (post year 2000) test labelled as a …