sured on a real operating GMD at Goldcorp's Peñasquito mine in Mexico. The quality of the tuned FE-model is demonstrated by a Campbell diagram showing a very good correlation between measured and calculated natural fre-quencies. Keywords Gearless Mill Drive, GMD, 42ft Mill size, Siemens, condition monitoring, finite element analysis, ring motor.
Following a successful commissioning and start-up, we believe that two grinding lines at Las Bambas, Perú, each consisting of one SAG Mill and one Ball Mill (this mill combination is uniquely specific to Las Bambas ore types), are operating at design throughput of close to 140,000 tpd and within the range predicted by DJB from a managed multi-sample …
The SAG mill was designed to treat 2,065 t h −1 of ore at a ball charge of 8% volume, total filling of 25% volume, and an operating mill speed of 74% of critical. The mill is fitted with 80 mm grates with total grate open area of 7.66 m 2 ( Hart et al., 2001 ).
This distribution affects the SAG mill load and the load affects directly the mill power and the efficiency of the mill operation (Van Nierop and Moys, 2001). If a SAG mill has been designed with a conventional power or specific energy model which do not consider the projected feed size distribution it is likely that this mill will reach the ...
operating cost in jaw crusher sag mill ball design copper. SAG is an acronym for semi-autogenous grinding. SAG mills are autogenous mills that also use grinding balls like a ball mill. A SAG mill is usually a primary or first stage grinder. SAG mills use a ball charge of 8 to 21%. [6] [7] The largest SAG mill is 42′ (12.8m) in ...
AG/SAG mill testing Procedures available to characterize grindability 8 Verret, F.-O., Chiasson, G. & McKen, A., 2011. SAG mill testing - An overview of the test procedures available to characterize ore grindability. SGS. (SVT)
the MinnovEX SPI (SAG Power Index) test using a 30 cm diameter SAG mill and a test procedure designed by John Star-key. The objective of the MinnovEX SPI test work was to provide design teams with an orebody profile of required SAG/ AG. 1. power from hardness data. The technical considerations and theory . involved in the measurement of SAG
Fig. 1. Typical semi-autogenous (SAG) mills This chapter presents a dynamic simulator of a semi-autogenous grinding operation deduced from first principles coupled to an on-line parameter estimation scheme able to simulate industrial operations for future control purposes. The proposed procedure for
The result is the most advanced and comprehensive instrument available for use on SAG and AG mills known as MillSlicer. DCL is based in Gainesville Florida, and we proudly design and manufacture our systems in the United States. Digital Control Lab. Digital Control Lab (DCL) is a USA based company with global reach. ...
OPERATION AND MAINTENANCE OF CRUSHER HOUSE FOR COAL HANDLING IN THERMAL ... consist of a crusher followed by a SAG mill followed by a ball mill. In this context, the SAG mill and ball mill are considered grinders rather than crushers. Crushers may be used to reduce the size,
SAG mill by feeding crushed pebbles The standard destination for crushed pebbles has been to return them to SAG feed. However, open …
For a process: Write enough detailed description of the procedure to guide the user through the process including details of startup, normal condition operation, temporary operation condition and emergency shut-down, etc. Also cover enough information, such as: 1. Chemical concentrations, gas amount 2. Pressure limits, temperature ranges 3.
Mill in Brazil and Lumwana having a 38ft, 18 MW SAG and one 26ft, 16 MW Ball Mill in Zambia, all three mills put in operation in 2008, as well as Los Bronces, Confluencia in Chile equipped with one 40ft SAG Mill of 22 MW and two 26ft Ball Mills of 16.4 MW commissioned in 2011. In the light of increasing interest in that technology various ...
The concentrator has a milling rate of 70,000t/d and is the largest single-circuit SAG-milling operation in the world. The SAG mill provides feed for ball milling to produce flotation feed, with the ball mills featuring variable-speed drives to enable the mills to handle the range of different ore hardness found at Antamina.
TABLE 1 Comparison of RoM and SAG mill operating regimes Speed, % critical Charge Filling, % total mill volume Bali filling, % total mill volume Internallength Aspect ratio, diameter/length Recycle stream Application AG/SAG 70- 80% 20 - 30% 4-15% 3-5m 0.7 -2 Trommel oversize & J)ebble crusher Primary grind South African RoM 75 -90% 35 - 45% 15 ...
The performance of tumbling mills is sensitive to the volumetric mill filling which influences grinding media wear rates, throughput, power draw, and product grind size from the circuit. Each of these performance parameters peaks at different filling values. In order to contin-uously optimize mill operation, it is vital to
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SAG mills respond well to a bi-modal feed, as reported in the work of Putland, Siddall and Gunstone (2004), however to produce this feed requires a screening plant to …
Safe operating procedures should be reviewed on a periodic basis, e.g. every 2 years, depending upon the level of risk, to ensure that the procedure remains current and appropriate. Reviews of safe operating procedures will be required sooner than two years in the event: • An incident occurs that relates to the safe operating procedure ;
SAG mills have a power higher than 10 MW. Even ball mills have a power larger than 10 MW. For this reason, they have an important impact in energy consumption and in the operation of the power distribution system. Figure 1. Picture of a typical GMD system for a SAG mill Figure 2 presents the power circuit of a cycloconverter fed synchronous motor.
• 28 MW GMD for a 40' SAG mill • 28 MW GMD for 42' SAG mill Whether it is size or an installation at the highest altitude (4600 m.a.s.l.), ABB's GMDs are well positioned to contribute to the building of larger and ever more powerful mills. — Leading the gearless mill drive evolution The ABB gearless mill drive (GMD) is the most powerful ...
Grinding is one of the most important and expensive steps of mineral processing. Therefore, different types of grinding mills such as rod mills, ball mills, semi-autogenous (SAG) mills and autogenous (AG) mills can be utilized for comminution of mineral ores [].Up to today, SAG mills and AG mills have been widely used to reduce operation costs and increase …
Kinross Paracatu and Process Technology and Innovation (PTI) have reviewed and optimized the operating strategies for the SAG mill circuit at …
SAG Mill Testing Test Procedures to Characterize Ore. involves replacing the mill charge several times throughout the test. The Bond tests are typically run for a minimum of seven cycles, while the MacPherson and pilot plant tests are operated for about 6-10 hours.
tailed in Chapters 4 through 7, especially the models of the SAG mill, oversize crusher, primary cyclones and SAG mill discharge screen. The source of the data utilised for model validation is detailed in Section 3.2. The development and validation of the unit operation models in isolation is described in Section 3.3.
crushers to SAG circuits, on both greenfield and retrofit projects, to increase feed rate to the SAG mill. In other words, crushing plants, from primary to quaternary circuits, are here to stay. There are three main steps in designing a good crushing …
OPERATION AND MAINTENANCE OF CRUSHER HOUSE FOR COAL HANDLING IN THERMAL ... consist of a crusher followed by a SAG mill followed by a ball mill. In this context, the SAG mill and ball mill are considered grinders rather than crushers. Crushers may be used to reduce the size,
The SAG mill optimisation challenge Running a SAG mill more efficientlywithout added expenseis. Chat Online; Ball Mill Operation -Grinding Circuit Startup Shutdown . · Normal Shutdown Sequence of Ball Mill and Grinding Circuit . Shut off cyanide metering pump. Put weight controller into MANUAL mode and turn controller output to 0 .
However, the SAG route is more power-intensive and, for very hard ores, comes with some process risk in predicting performance. More recently, a hybrid solution has become available in the form of high pressure grinding rolls (HPGRs), which can replace the third stage of crushing and also the SAG mill.
The mill should rotate in the proper direction. The mill gear should be lifted by the pinion causing a downward pressure on the pinion shaft bearing. Mills are made either right or left "hand". There are two methods of identifying the "hand" of the mill.
samples, is a more typical approach to grinding mill design. This paper summarises the requirements and deliverables of various bench-scale test procedures, their strengths and weaknesses, and cases where AG/SAG pilot testing should still be performed.
2006). The laboratory bench-scale SAG mill reproduces operating conditions of a commercial SAG mill, in a closed circuit dry grinding environment. The ground product for the laboratory SAG mill is then submitted to the Bond ball mill work index test. The number of …
11.3 Control of the equipment during operation 193 11.4 Lifecycle costs 193 11.5 Condition monitoring systems and their implementation 195 11.6 Temperature, pressure and vibration measurement 198 11.7 Campbell diagram 201 11.8 Gas turbine performance measurement and calculations 202 11.9 Protection systems and alarms 206
Blank spreadsheet that is pre-populated with the field names needed to import laboratory test results into the SAGMILLING circuit model testwork database (subscription required). Enter your test results, one per row, arranged into the columns indicated. To import into your testwork database, copy the block of cells starting with the top row ...
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