Testwork: Bond abrasion index - Revision history

Alex Doll: /* Modelling */

2020-12-22T16:27:53Z

Modelling

Alex Doll: /* Modelling */

2020-12-22T16:27:26Z

Modelling

Alex Doll: /* Test outputs */

2020-12-22T16:11:50Z

Test outputs

Alex Doll: /* Test outputs */

2015-07-24T19:26:35Z

Test outputs

Alex Doll: /* Modelling */

2013-12-05T22:47:57Z

Modelling

Alex Doll: Created page with "category:Testwork ==Testwork: Bond Abrasion Index== {{Test|name=Bond Abrasion Index|Abrev=Ai|Alt=|F80=19 000 µm|P80=n/a|Models=Steel wear calculation}} The Bond..."

2012-12-18T18:37:58Z

Created page with "category:Testwork ==Testwork: Bond Abrasion Index== {{Test|name=Bond Abrasion Index|Abrev=Ai|Alt=|F80=19 000 µm|P80=n/a|Models=Steel wear calculation}} The Bond..."

New page

[[category:Testwork]]
==Testwork: Bond Abrasion Index==
{{Test|name=Bond Abrasion Index|Abrev=Ai|Alt=|F80=19 000 µm|P80=n/a|Models=Steel wear calculation}}
The Bond Abrasion Index is a measure of how readily a rock sample will wear away steel that comes into contact with it. It is conventionally used to estimate the liner and media wear rate in rod mills, ball mills and crushers.

This is a batch test and returns a result in units of grams (the amount of metal that wears off the test coupon).

===Sample Requirements===

The minimum sample consists of 2 kg of material in the -19 mm by +13.5 mm size fraction. Sample finer than 13.5 mm cannot be used and should be excluded from the 2 kg sample weight measurement.

===Test Inputs===

Not applicable

===Test outputs===
The laboratory will report the '''Ai''' value, in grams. The test product particle size distribution is commonly provided, but is rarely used for performing calculations.

===Modelling===
Abrasion Index is not used directly in any of the power models. It is used in secondary calculations to estimate the wear of mill liners and media.

The wear formulae are widely published, including Page 752 of the "Mineral Processing Plant Design, Practice, and Control Proceedings", Volume 1, SME 2002.

===Discussion===
The Bond Abrasion Index is related to wear estimates by formulae generated by Fred Bond at Allis-Chalmers in the 1950's. The relationships are entirely empirical and were calibrated to the liner and media metallurgy of that era. Large-scale SAG milling was not included in the process operations that Bond surveyed (they wouldn't appear in their modern form for another twenty years), and no widely-accepted formula for estimating liner or ball wear in SAG mills using Abrasion Index has been published.

@@ Line 33: / Line 33: @@
 The ball wear equations in SAGMILLING.COM use a newer calibration formula that uses the Bond Abrasion Index was published by Carlos Rabanal &amp; Levi Guzmán of Moly Cop Andesur (Procemin 2013).  This model is referred to as the "Improved Benavente" equation and computes the 'specific wear constant' <math>k^{E}_{d}</math> measured as µm of ball wear per kWh/t of net mill power.
-<math>k^{E}_{d} = 1.36 \left [  \left ( \frac {Ai - 0.05}{0.20} \right ) ^{0.166} \left ( \frac {F_{80}}{5000} \right ) ^0.069 \left ( \frac {pH}{10} \right ) ^{-0.243} \right ] </math>
+<math>k^{E}_{d} = 1.36 \left [  \left ( \frac {Ai - 0.05}{0.20} \right ) ^{0.166} \left ( \frac {F_{80}}{5000} \right ) ^{0.069} \left ( \frac {pH}{10} \right ) ^{-0.243} \right ] </math>
 ===Discussion===

@@ Line 29: / Line 29: @@
 Abrasion Index is not used directly in any of the power models.  It is used in secondary calculations to estimate the wear of mill liners and media.
-The wear formulae are widely published, including Page 752 of the "Mineral Processing Plant Design, Practice, and Control Proceedings", Volume 1, SME 2002.
+The original wear formulae are widely published, including Page 752 of the "Mineral Processing Plant Design, Practice, and Control Proceedings", Volume 1, SME 2002.  These equations were based on the ball and liner metallurgy of the mid 20<sup>th</sup> century and may be obsolete for more advanced steel alloys.
-A newer calibration formula that uses the Bond Abrasion Index was published by Carlos Rabanal &amp; Levi Guzmán of Moly Cop Andesur (Procemin 2013).
+The ball wear equations in SAGMILLING.COM use a newer calibration formula that uses the Bond Abrasion Index was published by Carlos Rabanal &amp; Levi Guzmán of Moly Cop Andesur (Procemin 2013).  This model is referred to as the "Improved Benavente" equation and computes the 'specific wear constant' <math>k^{E}_{d}</math> measured as µm of ball wear per kWh/t of net mill power.
 ===Discussion===

← Older revision		Revision as of 16:11, 22 December 2020
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	* '''Ai''' value, in grams. The test product particle size distribution is commonly provided, but is rarely used for performing calculations.		* '''Ai''' value, in grams. The test product particle size distribution is commonly provided, but is rarely used for performing calculations.

		+	The test consists of measuring the weight of a standard steel paddle before and after contact with the ore sample in a tumbling mill with a specific geometry. The reported '''Ai''' value is the quantity of mass (measured in grams) lost by the paddle during the test.

	Extra field available for modelling		Extra field available for modelling

← Older revision		Revision as of 22:47, 5 December 2013
Line 26:		Line 26:
	The wear formulae are widely published, including Page 752 of the "Mineral Processing Plant Design, Practice, and Control Proceedings", Volume 1, SME 2002.		The wear formulae are widely published, including Page 752 of the "Mineral Processing Plant Design, Practice, and Control Proceedings", Volume 1, SME 2002.

		+	A newer calibration formula that uses the Bond Abrasion Index was published by Carlos Rabanal & Levi Guzmán of Moly Cop Andesur (Procemin 2013).

	===Discussion===		===Discussion===

@@ Line 18: / Line 18: @@
 ===Test outputs===
-The laboratory will report the '''Ai''' value, in grams.  The test product particle size distribution is commonly provided, but is rarely used for performing calculations.
+* '''Ai''' value, in grams.  The test product particle size distribution is commonly provided, but is rarely used for performing calculations.
 ===Modelling===