The first Gearless Mill Drive (GMD) with a power of 6.5 MW was installed 1969 in a cement milling process in the cement plant Le Havre in France. In the first few years, the GMD was only used in the cement industry. The GMD is also known as …

Mills & Kilns. Hofmann Engineering has a long and successful history of designing, manufacturing, installing and servicing mill and kiln parts. With a capability of manufacturing girth gears up to 15m (49ft) diameter and shells up to 13.4m (44ft) diameter, Hofmann Engineering is in a unique position to supply these large parts.

Girth gears can be supplied individually, or as part of a fully optimised package which includes: • Mill drive gearbox • Girth gear • Pinions • Barring drive • Auxiliary equipment including couplings, brakes, pedestal bearings and clutches Whichever option you chose, rest assured that your girth gear will be designed

Get the most out of your open gears at every stage of life using the industry's highest performing lubricant portfolio. Formulated specifically for open gear drives, our full range of specialty lubricants is designed to maximize your productivity and lower operational costs. This industry-leading portfolio now includes Klüberfluid C-PG 17 ...

Figure 2: Two pinion gears drive the girth gear on this double-drive cement ball mill. Courtesy: Lubrilog/STLE. For vertically moving gears, the spray nozzles can be contained in a covered box that delivers an atomized, directed spray to the surface of the girth gear as it passes through the box, Kumar said. This type of gear assembly requires ...

Girth gears are now being used to drive ball and SAG mills having total installed power in excess of 17,000 kW (23,000 hp). The development of high-hardness materials suitable for these applications has resulted in the design and manufacturing of cast girth gears up to 350 HBW in steel and 340 HBW in ductile iron.

Girth gears fall into two basic categories; flange mounted and tangential spring mounted. Flange-mounted girth gears, the more common of the two, are most frequently utilized in …

materials, our line of girth gears is ensuring high-performance for your mill or kiln. Get the best from your mill or kiln with our girth gears Technology We build our fabricated girth gears using forged gear rim material and bodies made in an electro-welded structure. Compared to girth gears with cast base material, the manufacturing process

not an option for a 42ft Gearless Mill Drive. The ring motor is not self-supported and needs the mill to fix the rotor poles to and it needs the mill foundation to support the stator. Finally you would need a few thousand tons of ore and possibly even an earthquake would be needed to have a realistic test environment representative of a mine site.

SAG Mill Components Once the basic operating conditions have been defined for the mill designer then, and only then, can he begin taking into account shell and head stresses and trunnion bearing sizes …

Global Physical Asset Management | 465 followers on LinkedIn. Third-party girth gear engineering, installation, risk assessments, E2905 inspections, pinion alignments and maintenance | Our third-party capabilities are in the engineering, design, manufacture, installation, inspection and maintenance of large girth gear systems. We provide a …

Traditionally, the number of shell lifters used in a SAG mill is equal to twice the number of the feet in the mill shell diameter (e.g., a 34-ft-diameter mill shell would have 68 shell lifters). This is also called a 2-D shell lining. Eliminating some shell lifters increases the volume of charge between the lifters

The MDX range of mill drives is specifically designed for mill applications across a range of minerals processing applications. 11 Pinions David Brown can manufacture both integral and non-integral mill pinions, for SAG and ball mill applications and rotary kilns. Girth gears Girth gears are used to drive horizontal grinding mills globally. Our ...

The mill drive system consists of the main mill motor, the main reduction gear box, mill pinion and girth gear. The mill is also equipped with a barring drive which is either connected to the main drive reduction unit or alternatively mounted at the back of the main motor. Refer to Figure 2 for a schematic of the mill drive system.

Girth Gear Inspection Deliverables: We provide a complete non-destructive examination of the integrity of the mill gear teeth in accordance with ASTM E2905, for macro-pitting and cracking. We analysis the data as we scan the teeth. If cracks are detected, we provide remedial relief (excavating services) during the inspection site visit.

Girth Gears. These are the gears that have a multitude of industrial applications. These gears are pretty different from others as they are manufactured in numerous segments such as two, four, or eight equal sizes. These kinds of gears' practical benefits are their easy installation, low initial cost, and simple operation.

Gears and pinions A complete range of gear and pinion sets, inspections, design, installation and alignment services to drive your mill's performance Introducing a new name Outotec is proud to announce the launch of our new rebranded offer: Outotec Gears and Pinions. You can expect the same quality supported by decades of gearing and

Grinding Mill Gear Assembly. We will begin with the mill's bull gear assembly and work towards the motor, The BULL GEAR, sometimes called the RING GEAR is designed to turn the mill transforming the energy of the motor into motion for the mill. By mill we refer to Ball Mills, Rod Mills and SAG Mills.

Grinding (Ball & SAG Mills) SAG Mill shells, Ball/Rod for Mill shells, Ball Mill head in halves, SAG Mill heads. Girth gears, Pinions, Trunnions, Bearings, Lubrication Units. Millrex dual-pinion self-aligning (2,3 & 4 stages) and Ermill single-pinion self-aligning compact lateral drives. Ermaster single, multi-stage and inching drive brake ...

Gearless mill drives (GMDs) constitute a compelling alternative to traditional ring-geared mill drives (RMDs) in such environments. Both drive types can be used to power large semi-autogenous (SAG), ball and autogenous mills, but GMDs are proven to offer superior availability, uptime and efficiency. When the first GMD was developed by …

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What is the difference between a SAG mill and ball mill?hgminingpartsOptimizing your SAG mill operation

WebABB's Gearless mill drive system is the most powerful mill drive system in the market to power semiautogenous (SAG), ball and autogenous (AG) mills.

With a variety of options for cast, fabricated steel or SG iron and multi-segmented gears, David Brown Santasalo is your one stop shop for girth gears for AG, SAG, ball mill and crushing applications. Engineered in segments, starting from two and with no upper limit, we can manufacture girth gears up to 14 metres diameter.

The mill drive is provided with an auxiliary drive for slow turning of the mill. The LGDX includes two independent lubrication systems, one which services the girth gear guard and intakes more dust, and a second which supplies oil for the fast-rotating gearing and bearings and stays clean. If requested, however, the mills can be

This is an update of work presented at the SAG 2001 conference on the Cadia gears [1]. ... This expansion explained why one of the girth gears at Cadia failed at the drive end and the other failed at the non-drive end. The expansion is shown in Figure 1. The work in [1] was limited by the size of the model we were able to create to simulate …

Girth and Ring Gears. If you need large diameter girth gears in your process machinery, then you need a product you can rely on. With a variety of options for cast, fabricated steel or SG iron and multi-segmented gears, David Brown Santasalo is your one stop shop for girth gears for AG, SAG, ball mill, kiln and dryer applications. Book an ...

SAG Mill Components. ... Manufacturing limitations from gear vendors determine the minimum number of pinions which can be used to drive the mill as well as the number of gear sections. If the mill requires approximately 6000 horsepower or less, it is possible to drive it with a single pinion. To date, however, economics has dictated that …

By delivering the lateral gear drive together with the girth gear, we ensure that both components match perfectly. Our girth gears have a key role in meeting the highest power demands in vertical rollers mills. The MAX Drive powers vertical roller mills up to 15,000 kW with two spur gear drive units that mesh with the girth gear under the mill ...

The single helical SAG mill girth gear, which is cast in four pieces, has 362 teeth, 0.75 DP, 863.6 mm face width, 12.4 m outside diameter and a 10.5 m diameter bore. It's manufactured ... 1605 Industrial Drive Auburn, CA 95603 Phone (530) 885-1939 Fax (530) 885-8157 Web: Call 530 885-1939 or visit …

The ABB gearless mill drive (GMD) is the most powerful mill drive system available, combining the highest levels of efficiency, reliability, flexibility and availability. The …

B Pfimary SAG, 30x11 Fixed speed ac synchronized motor coupled mill, $2.9 million 17,000 to a gear drive with an air clutch. motor, $568,000 inching drive, $289,500 6500 …

Our material handling gear systems are in operation in some of the world's harshest environments – thermal efficiency, mounting and sealing systems are optimised to ensure supreme performance whatever the weather. Extensive experience in delivering large, multi-segment, cast and fabricated girth gears for pyro processing and grinding ...

Sag Mill Drives Girth Gears At 18 000 Hp Motors How Much ... sag mill drives: girth gears at 18,000 hp motors in How Much Crusher[], news, photos and information about orlando sentinel the smarter travel ... what types of ore can be crushed by sag mill.

With inside dimensions of 36-ft diam. and 19-ft long, this semi-autogenous grinding mill (SAG — see next section) will use a 43-ft diam. ring-gear drive to transmit 18,000 hp and handle up to ...

mill gears. Most of these fluids meet the AGMA criteria. They provide excellent drainability but require a good sealing of the gear housing. High-viscosity fluids can show disadvantages if used on low-speed kiln gears, where a sufficient lubricant layer can hardly build up with pure oils. To separate the meshing gear flanks,

Segmented girth gears - flexible concept for diverse combinations. Traditional girth gears generally consist of two to four segments and are assembled together for processing. This requires extremely large and …

Girth gear drive and central drive are mechanical systems designed to reduce the motor speed to the working speed of the mill. Transmission is via gears. Gear units comprise …

The hours, days or weeks needed to get a mill back on line are often filled with tense periods of trouble-shooting and scrambling to locate and acquire needed parts, and the characteristics that make SAG mills such robust performers — powerful drives, massive components and capacity to carry a thousand tons or more of ore and grinding balls ...

Bordi: "We are increasing the 'tools in the chest' by offering some alternatives – for example – if the circuit actually needs a 38 ft, 20 MW SAG mill, you now have the option of a 38 ft gear driven mill. At this size gearless drive is a viable option, but it is significantly more expensive and therefore can pose a challenge.

Autogenous grinding is favored when the ore is quite competent and a fine grind is required. Semi-autogenous grinding is applied when fine crushing could cause severe problems or when ore is variable in hardness or competency. Figure 2 shows a typical conventional crushing-grinding circuit with three stages of crushing followed by …