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Abstract
The new concentration plant of the Sarcheshmeh copper complex with the design throughput of 900 t/h started in 2005. Unlike the old plant which has three conventional crushing stages, the new plant uses a 32 by 16 ft fixed speed SAG mill which is driven by two 5500 hp motors. The liners are chrome-molybdenum steel casting type with a Brinell hardness between 325 and 375 with the lifter face angle of 14°. The shell liner consists of 120 (two 60 rows) pieces with a High-High configuration in a rail design. In the first seven months of operation, the plant availability due to various mechanical and operational problems was significantly lower than the expected value (85% vs. 47%). Contribution of the SAG mill in the plant shutdown time due to liner change amounted to 13%. In the same period, 70 liners out of 120 had to be changed at six different stages because of breakage. The main reason for liner breakage was postulated to be working with no or little ore mostly because of ore type change and a lack of experience. One implemented remedy was to change the make-up ball size from 125mm to 100mm and keep the ball charge between 8-10%. Upon gaining experience, the availability of the SAG mill for the second set of liners increased to 75% and the number of broken liners reduced to 2. A specially designed device was designed and built to measure accurately the wear profile of the liners. Using Solidworks©, a commercial mechanical software, and the liner profile measurements, the 3-D modeled liners were placed in a simulated mill. A criterion based on the liner weight and surface was proposed to determine the liner removal time. It was found that the liner wear profile is non-uniform along the liner length and the highest wear occurs between 1.25m and 2.75m of the mill length. The liners of the first half of the mill from the feed end showed more wear compared to that of the second half. The liner consumption for the first and second liner sets was found to be 19 and 18 grams per ton of ore ground, respectively.

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	All Years to Access Full-Text Export citations SAG MILL LINER WEAR AND BREAKAGE AT THE NEW CONCENTRATION PLANT OF THE SARCHESHMEH COPPER COMPLEX By S. Banisi, M. Hadizadeh, H. Mahmoodabadi, and A. Eilkhani Published in SAG Conference at 2006 Direct link: http://kmpchemmat.ir/pii/36396 Abstract The new concentration plant of the Sarcheshmeh copper complex with the design throughput of 900 t/h started in 2005. Unlike the old plant which has three conventional crushing stages, the new plant uses a 32 by 16 ft fixed speed SAG mill which is driven by two 5500 hp motors. The liners are chrome-molybdenum steel casting type with a Brinell hardness between 325 and 375 with the lifter face angle of 14°. The shell liner consists of 120 (two 60 rows) pieces with a High-High configuration in a rail design. In the first seven months of operation, the plant availability due to various mechanical and operational problems was significantly lower than the expected value (85% vs. 47%). Contribution of the SAG mill in the plant shutdown time due to liner change amounted to 13%. In the same period, 70 liners out of 120 had to be changed at six different stages because of breakage. The main reason for liner breakage was postulated to be working with no or little ore mostly because of ore type change and a lack of experience. One implemented remedy was to change the make-up ball size from 125mm to 100mm and keep the ball charge between 8-10%. Upon gaining experience, the availability of the SAG mill for the second set of liners increased to 75% and the number of broken liners reduced to 2. A specially designed device was designed and built to measure accurately the wear profile of the liners. Using Solidworks©, a commercial mechanical software, and the liner profile measurements, the 3-D modeled liners were placed in a simulated mill. A criterion based on the liner weight and surface was proposed to determine the liner removal time. It was found that the liner wear profile is non-uniform along the liner length and the highest wear occurs between 1.25m and 2.75m of the mill length. The liners of the first half of the mill from the feed end showed more wear compared to that of the second half. The liner consumption for the first and second liner sets was found to be 19 and 18 grams per ton of ore ground, respectively.