bond work index value for limestone.oct 01, 2009 this lower value results from the difference between the total mgco and the mgco strongly bound in this is primarily due to differences in the bond work index of the different limestone
bond working index or bwi of limestone. 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 kwht required to grind to that size magdalinovic measured the bond work index of three ore types using different test screen sizes He produced a correlation between the mass of test screen
As a fast method, the determination of the bond index from the hardgrove index is almost matching with measured bonds work index. the bonds work index of the above rock samples calculated from the hardgrove index value has shown a variation from 7.7 to 10.3 kwhsh.t.
bond work index epri method size astm this value will include any insoluble calcium content. typically bond work index is checked semi-annually. however, at buyers request seller shall perform additional tests.
pdf a quick method for bond work index approximatepdf a quick method for bond work index approximatethe 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, bond mill work index of limestone
last three cycles are averaged. the average value is taken as the standard bond grindability. experiments firstly, standard bonds grindability tests were made for six limestone samples. result of tests. bond grindability value of limestone sample were appeared 6.14 grev, 2.89 grev, 2.58 grev, 2.48 grev, 2.42 grev and 1.54 grev
according to fhw-if-17 typical values of ultimate bond for drilled and grouted nails installed in various soils and using different drilling methods are presented in table 3.10. the values in this table correspond to gravity grouting only.
according to bond 0.5 and according to charles and stamboliadis can take any value near these two. In the case that the initial size is infinite and the final size is 100 then by definition the required specific energy is called work index ,100 the value of the constant in can be calculated
bond index test test conducted on a bond index testing mill of sample milled for 100 revolutions. new number of revolutions is calculated to produce fines equal to 13.5 of the total charge of the mill. the bond work index expresses the resistance of the material to
their diameter the point load index, id, is equal to where is the load at rupture and is the core diameter. rock specimens break since tensile cracks develop parallel to the loading direction. In general, it has been found that the value of the load at failure depends largely on the core diameter. hence, the results of point
bond work index 12.0 maximum 14.0 maximum epri method size not to exceed 25% passing mesh screen of applicable lot inch or of applicable lot 35% passing mesh screen astm this value
the strength values range from a low of 9.16 mpa for marl to a high of 101.08 mpa for sakessar massive limestone. the coefficient of variation ranges from 10.3 to 37.7%. 4.2 point load test results the results of the point load test are given in table the point load strength index values range from 0.36 mpa for the jutana sandstone
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bond work index the amount of energy required by plant to crush material los angeles value the los angeles test is commonly used to evaluate the hardness of aggregates to find the suitability of aggregates for use in road construction. therefore, the road aggregates should be hard enough to resist abrasion. ucs
limestone analyses via bond work index for full scale on-site limestone analyses via bond work index limestone is typically received with a diameter of about in. fraction is returned to the ball mill.
oct 15, 2015 summary of hgi and bwi data for all samples; hardgrove grindability index hgi, 80% passing feed size 80, 80% passing product size 80, grindability per revolution final revolution count bond work index work input gross calorific value on dry basis bond work index-gross calorific value ratio
limestone bond work index venezuela guide de. limestone bond ball mill work index youtube pdf kb maney publishing limestone are ground together in a ball mill to get sufficient fineness for the bond ball mill index test jktech measuring ore grindability in balls mills the bond ball mill work index is a measure of the resistance of the material to grinding in a ball mill
alternative approaches for determination of bond work index on approach, is bonds grindability test and the second one is hardgrove index, In recent, the brittleness testfriability value of bauxite, limestone, barite, marble read more
bond mill work index for limestone bond mill work index for limestone; lab equipment, rod mill, titan bond work index rod mill, canada, p.o.r. rolls.jpg. get price. bond work index tables scribd. here there are given tables from various sources for the bond work index values of mining
the bonds standard ball mill is used to determine the work index value of differ ent samples. the bond work index is defined as the kilowatt-hours per short ton required to break from infinite size to a product size of 80% passing 100 If the breakage characteristics of a material remain constant over all size ranges, the calcul ated work
the coal fines are sorted and the quantity of coal less than a specified size is recorded and converted into a hardgrove grindability index value typical resulting hgi values lie between and 100
results of tests by bond. for the calculation of work index Wi from hgi values bond proposed by the following formula: hgi. 0,5 In 1961 bond specifies for calculation the following modified formula: 435 Wi hg,91
At least to kg sample material is required to simulate a closed grinding circuit in a ball or rod mill. the rod mill work index is used for particle size determination in a size range from mm down to 2.1 mm whereas ball mill work index is used for the range from 2.1 mm down to 100 adjustment of grinding parameters:
bond work index mineral work index mineral work index barite 4.7 6.9 glass 3.4 basalt 17.0 22.5 granite 15.1 cement clinker 14.8 limestone 9.0 12.8 coal 12.5 13.0 mica 148.0 dolomite 9.0 12.4 quartz 13.6 14.1 feldspar 12.8 quartzite 9.6 bond work index
apr 17, 2013 ball mill bond work index for limestone ore beneficiation plant. the bond work index indicates a relative grindability of the limestone.the work index number is developed by grinding a small sample of the material in a more detailed
bonds law is often written in terms of the work index as, where the work index is defined as the energy required per unit mass in kwhton to reduce an infinitely large particles to 100 In the above equation, unit of is in mm, of is kwh and of is in ton. work index for common materials is material Wi (kwhton
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process analysis and energy efficiency improvement ON portland limestone cement grinding circuit by sixto humberto aguero b.s. universidad nacional autonoma de honduras, 1992
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.