Gearless mill drives
GMDs: 22 MW GMD for 28' ball mill 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 …
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GMDs: 22 MW GMD for 28' ball mill 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 …
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AG mills (or SAG mills with low ball charges) are often used in single-stage grinding applications. Based on their higher throughput and coarser grind relative to AG mills, it is more common for SAG mills to he used as the primary stage of grinding, followed by a second stage of milling. AG/SAG circuits producing a fine grind (particularly ...
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This puts the application in the realm of a single mill with gearless drive. xPower demand of more than 28 MW. ... The SAG mill model in the JKSimMet software has not been shown to accurately reproduce the performance of a single stage mill for greenfield design. A review of most modern power models shows that the prediction of
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Laguna Seca concentrator uses a SAG mill and three ball mills, all driven by gearless mill drive (GMD) systems. Table 1 gives an overview of the basic technical data of the installed drives. TABLE I. MILLS AND THEIR DRIVES IN THE LAGUNA SECA PLANT Equipment Drive Comments SAG Mill (Semi-autogenous Grinding) Quantity : 1 unit
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Whether you're talking about SAG or a ball mill, space is a delicate issue, especially in the concentrator. That's why we always design our Gearless mill drives drives to combine maximum performance with limited space requirements. Suitable foundation and adequate ground conditions Since our solutions have a low motor weight, this notice-
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gear drives". Award - Landmark Papers: SAG 2001 Conference. ... World's Largest SAG Mill Gearless Drive" and "Failure Analysis of Ball Mill Gears". Page 2 of 6 . PREVIOUS POSITIONS: 1994-2001 Frank Grigg & Associates Pty Ltd -Director . 1988-1994 M&A Mining & Industrial Consultants Pty Ltd – Senior Mechanical Engineer .
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SAG mills can produce a lot of impact if operated with a high ball charge and low filling. Rod and AG mills can produce a lot of attrition and varying amounts of impact and abrasion. Arraying different mills can take advantage of the strengths of …
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Advantages of SAG Mills: 1) ... Schematic of Typical Gear less Mill Driv e system [19] There is n o gear, because ... Since th e gearless mill drive i s typically .
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The world's most powerful gearless mill drives The three gearless mill drive (GMD) systems are the ABB most powerful ever made. The GMD for the 40-foot SAG mill has a power rating of 28 megawatts (MW), and the GMDs for the two 28-foot ball mills have a power rating of 22 MW. They are the largest diameter and most powerful SAG and ball …
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In June 1998, the world's largest grinding mill, the 40 ft (12.2 m) diameter 20 MW Cadia gearless SAG mill, was commissioned. This was a leap of over 40% above the largest operating SAG mill. A significant saving in capital …
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Siemens' gearless drive technology of 99.46 to 99.71% - as confirmed by real operational data from the Antapaccay mine in Peru. It was the first plant worldwide to use gearless drives for both applications. KEYWORDS Gearless Mill Drives, Gearless Conveyor Drives, Availability, SAG Mill, Ball Mill, Overland Conveyor, Antapaccay 15
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motor, ωrated as Hz, which for a Gearless Mill Drive is simply ϕRPM ÷ 60. For a gear driven mill, the motor For a gear driven mill, the motor speed is a function of the mill …
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Ringmotor of the Gearless Mill Drive (GMD) System. CYCLOCONVERTER Principle The Cycloconverter is a frequency changer which converts a poly-phase voltage with the frequency f1 into a single or poly-phase voltage with a different, lower frequency f2. On Gearless Mill Drives (GMD), the operational output frequency varies from 0.3 Hz up to …
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gearless ringmotor. Typical gear driven mill and gearless mill with a ringmo-tor are shown in Figs. 1 and 2. Early SAG mill designs using gear drives were limited in the amount of power that could be applied to the pin-ions, 3.7 MPa (5000 hp). The exception to this design was the Hibbing taconite operation. It used two4.47 MPa (6000 hp) motors ...
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Abstract. Gearless mill drives (GMD) are a well established solution for grinding applications in the minerals and mining industries. The paper describes the functionality …
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The gearless mill drive (GMD) has been continuously developed since its introduction in 1969. The ... SAG Mill Figure 2 Core pressing system with spring plate/washer and re-tightening statistics in a typical installation Access to the inside of …
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For economy of scale, new projects consider grinding circuits with SAG and ball mills with 36′ or larger mill diameters with cycloconverter-fed drives with powers in the range near 20. MW.. For the huge volume of slurry flows, big pumps with low-speed gearless drives fed by medium voltage converters in the range of 1–2 MW are being …
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Image credit: Rexnord Corporation. An inching drive is used as an auxiliary system to the main drive for a large machine such as a ball mill, industrial kiln, conveyor, or elevator. Its purpose is to turn the …
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Eleven 5MW gearless drives with synchronous motors running at low speeds (50-60rpm) drive three conveyors; two with four motors each and one with three. Two 20MW conveyors transport the ore from the open pit operation to the surface, overcoming an elevation change of around 1,300m, while the second conveyor feeds into a slightly smaller, 15MW ...
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Gearless or ring motor drives; Twin CCV or Cycloconverter; Twin ICI or Load Commutated Inverters using variable frequency; Quadramatic II LCI drive. For power requirements up to approximately 4,476 kW (6,000 hp), it is convenient to drive the mill through a ring gear and single pinion arrangement.
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The current paper looks at evaluating the merits of large geared mills versus gearless driven mills by evaluating the following factors: The capability of currently available …
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The current paper looks at evaluating the merits of large geared mills versus gearless driven mills by evaluating the following factors: ... Among the many reasons that geared drives on large SAG mills are not favoured, is due to not having an efficient variable speed drive option (60 to 80% critical speed), which is required for process ...
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ABB continuously extends technical and performance frontiers of ring-geared mill drive (RMD) technology to fit your site requirements. We provide optimized mill drive solutions for all types of ring-geared mills: low and high speed, single and dual pinion, with and without a gearbox — all designed for reliable, long life and low maintenance ...
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Case studies: Aktogay and Bozshakol. ABB has partnered with Kaz Minerals to supply GMDs for the company's Aktogay and Bozshakol copper mines in Kazakhstan, both of which are expected to process 25 Mt/y of ore. ABB was awarded a multi-million contract to provide a 28 MW GMD for a 40 ft (12.2 m) SAG mill and two 22 MW drives …
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Gearless Mill Drive (GMD) or a conventional gear drive. T = P × (2π × ω)−1 ( 1 ) where, T is motor output torque measured at the output shaft (pinion) or mill shell (GMD), N·m; P is motor output power measured at the output shaft (pinion) or mill shell (GMD), W; ω is the motor speed, revolutions per second or Hz.
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Do more with less - go gearless. Mine operators are challenged with moving more material on conveyors that may cover distances in the tens of kilometers and ascend steep gradients. To increase overall reliability, …
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SLIP ENERGY RECOVERY DRIVE Geared and Gearless SAG Mills must consider variable speed ability for process reasons Issues regarding load sharing & torque pulsation Slip Energy ... then largest gear drive in operation on a SAG mill (34ft x 18ft) at Escondida 13.4MW (18,000hp) - 1995. Shop test run SINO Iron project 7.9m X 13.6m Ball Mill Twin …
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Gearless Get more mill with drives less. Go Gearless gearless mill drives: Increased process availability, reliability and energy efficiency. Gearless mill drive (GMD) systems …
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reasonable working estimate to use in the case of gear-and-pinion drives would be 6-7%, ie the estimated power at pinion would be about 6-7% lower than the gross power draw. Gearless drives (also known as wrap-around motors) are quite different to gear-and-pinion drives. They do not have gears or pinions and ... AG/SAG mills in the data
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This two-stage grinding circuit consists of a 40 ft SAG mill with a 20 MW Siemens gearless drive and two parallel 10 MW gear driven ball mills. Siemens has now fitted the SAG mill with a Sinamics SL 150 cycloconverter for closed-loop control as well as with a Sinamics DCM control module for the excitation circuit – the first time that both ...
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