• Mill inspection via the inlet is possible, thus increasing personnel safety • Less wear and simpler form of wear lining on straight end walls • Short inlet cone • Less bearing clearance and thus less mill shell deflection polysius ® ball mill with direct drive There are two types of gear unit available for the mill drive unit.

Ball Mill Failure Modes Pdf The Failure and ball mill journal bearing ball mill failure modes pdf ball mill pinion failure in south Get Price And Support Online A Publication of the Lubrication Engineers Technical if a ball mill or SAG mill is out of operation for one hour at a Chilean Copper Mine it costs the mine 200 000 or 300 000 failure or ...

By mill we refer to Ball Mills, Rod Mills and SAG Mills. Anything gear and pinion really. The discharge end of the mill; For the operator this only becomes a problem should the bolts that hold the liners in begin to leak water and ground rock. …

the mill builder can provide the gear designer with input power and output speed. The next step is the interface dimen-sions. Since the gear needs to turn the mill, it needs to have a bore larger than the mill outside diameter. The mill out-side diameter is a function of the grind-ing process selected. Autogenous mills

Re Pinion pitting. One of the main reasons for mill gear and pinion problems has been incorrect lubricant and/or incorrect application of lubricant. Misalignment of pinion with the gear can make the problem much worse. It is essential to get both lubrication and alignment right to avoid problems.

The Outotec slurry wheel upgrade is a retrofit sealing solution for the grinding mill feed end. The existing configuration is replaced with a new and improved slurry return system featuring a unique water-wheel design that significantly improves the material containment of the feed ends.

P-F Curve Mill Gearing Diagram (with examples) When ingress and indentation starts (Plastic Deformation, Abrasion, Localized Overloading) — when detectable crack forms ~ 3mm with ECA — cracks relieved — functional failure. There two main points of the PF curve:

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. When standing at the feed end of the mill, and facing the mill, if the mill rotates clockwise, it is a right hand mill.

The first major commissioning failure on the SAG mill occurred during installation when the mill was inched without adequate lubricant flow, …

of the SAG mill and ball mill (both rated at 6000 kW with a single pinion drive). The capacity of the SAG mill was not fully utilized, as the actual operating power draw was only 3358 kW. This meant it was only operating at 56% of its maximum power, providing large room for …

Wet Grid Ball Mill |. Capacity: 0.5-500TPH Feed Size: ≤25 mm. Grid ball mill is widely used in smashing all kinds of ores and other materials, ore dressing and national economic departments like building and chemical industries etc. The size of ore shall not exceed 65mm and the best feed size is under 6mm. The effect in this job is better ...

As mentioned the Sag Mill was run for 8 days at its limit 5,500kwto 5700 kw and this is the time the high vibration started, I still have the motor suspect but the gearing pinion and girth gear did not look too bad.

Firstly, there was a serious flaw in the power configuration of the SAG mill and ball mill (both rated at 6000 kW with a single pinion drive). The capacity of the SAG mill was not fully utilized, as the actual operating power draw was only 3358 kW. This meant it was only operating at 56% of its maximum power, providing large room for improvement.

Ball Mill PINION SHAFT BEARINGS. Pinion shaft bearings are of the SKF anti-friction type mounted in a common twin bearing assembly. Bearings are fixed in place so that the pinion shaft of the mill is always in alignment with the drive components. V-belt driven mills are furnished with an outboard bearing of similar construction.

SAG Mill Components. Once the basic operating conditions have been defined for the mill designer then, and only then, can he begin taking into …

SAG mill conference, provided details of the then largest gear drive in operation on a SAG mill (34ft x 18ft) at ndida 13.4MW, which began operation in 1995. The reason for not having larger gear drives was due to the limitation of gear manufacturers not having access to larger single piece special alloy castings. To the benefit of

The larger the mill, the greater are the stresses between the shells and heads and the trunnions and heads. In the early 1970s, maintenance problems related to the application of gear and pinion and large speed reducer drives on dry grinding cement mills of long length drove operators to seek an alternative drive design.

SAG mill drives (as GMDs) by some operators and principal motor designers/manufacturers until the reasons for known problems in design or manufacturing were better understood and resolved. Accordingly, the latest 40 ft dia. SAG mill is rated at 29 MW and 78% C.S., with a 42 ft dia. mill built but not yet operational. The more recent option

general, the bigger the mill diameter, the lower are the mill operating and critical speeds. Thus, for larger mills the number of poles will increase. As a result, the number of poles can vary from 48 to 72 poles (Fig. 3.) with typical mill speed requirements of about 10 rpm for larger SAG mills and about 15 rpm for smaller ball mills. Figure 3.

Both the SAG mill and ball mill are each driven by two gear units. Because, on a conventional drive variant, only one engagement per pinion with the girth gear is possible per side, an economic power limit of about 8 MW per drive is in effect. With the DMG2 gear units, Siemens said this limit expands to as much as 12 MW per drive.

When SAG mill liner bolts loosen, break or stretch beyond limits, liner impairment and degraded performance are generally next on the agenda, followed by mill stoppage for repair or replacement. ... Finding and fixing issues early will avoid undesired wear, broken teeth or even complete failure of the gear and pinion.

The gearless mill drive eliminates ring-gear, pinion, gearbox, coupling, motor shaft and motor bearings, used within a conventional mill drive ... • 28 MW GMD for a 40' SAG mill • 28 MW GMD for 42' SAG mill ... possibility of the catastrophic inter-turn failure by default. They make it possible to have real motor

Online pinion temperature monitoring of the pinion with infrared temperature sensors is the most consistent and effective means of detecting misalignment of gear driven mill systems, allowing the user to quickly detect and correct any misalignment that may develop.. A common failure cause of gear driven mill systems is misalignment, which in its most severe form can cause …

pinion (Fig. 7) corresponds to the damage observed on its mating gear. However, the level of damage on the low-speed pinion is much more se vere than that on the mating, low-speed gear. Since the pinion sees many more cycles than the gear, the disparity in the level of damage is expected. The location

drive application is a dual-pinion SAG mill driven by two 5,000 kW wound rotor induction motors (WRIM). Two TMdrive-10SPRs control motor speed by recovering rotor current and returning the power to the utility supply. Configured in a twin motor arrangement, the motors share load in the tandem mill. The Customer Need

The graph of SAG pinion energy (to 1.7mm) Vs Bond BM Wi is given in Figure 3. Excluding the very soft and very hard projects, shows that the database in general does support a broad correlation between SAG and ball mill hardness but that the function is -defined to be useful in sizing a SAG too ill mill from a Bond BM Wi measurement.

This white paper focuses on the work carried out by Alphatec Engineering in the rehabilitation of the mounting system (concrete foundation, anchoring, and grout) of a pinion-bearing pedestal of an 8,5 m ø x 3,8 m semi-autogenous grinding mill …

Horsburgh & Scott (H&S) was contacted by a sugar mill in Central America due to a catastrophic failure on a competitor's gearbox that was driving one of their main mills. The failure threatened to reduce their profits by over 10% for the 2014/2015 grinding season.

SAG MILL BALL MILLS MILL DESIGN DATA. These projects involved SAG mills from 26 to 36 ft in diameter, with installed power in the range 9.7 to 16.8 MW using single, twin pinion, and gearless technology for drives over 16 MW. The ball mills used varied from 13.5 to 25 ft in diameter, with installed power in the range 1.85

The largest ringmotor- driven mill in the world is a 36-ft diam., 16,000-hp SAG mill that processes up to 2,000 tons of ore per hour. Located at Kennecott Utah Copper near Salt Lake, this mill ...