sag and ball mill drive failures

  • STEPPING FORWARD USING VARIABLE SPEED DRIVES

    2018 2 20 The breakage rate function shape of the SAG mill is largely governed by the mill load particle size distribution and mill speed The feed in the mill contains fractions of ore that serves as the grinding media Larger ore fractions break the smaller particles but also breakdown themselves and exit the mill as a

    Chat Online
  • SAG Mill Control It Shouldnt be that Hard

    2010 4 13 SAG mill control fundamentally means managing the load in the mill by adjusting the feed rate of ore to the mill and/or manipulating the rotational speed of the mill The best way to measure load is to mount the mill on load cells The load cells are calibrated to measure the total weight of water grinding media balls and ore in the mill

    Chat Online
  • THE ENGINEERING AND PROCESS EFFECTS OF

    The paper specifically describes SAG mills but the equations and principles apply equally to any conventional tumbling mill such as AG ball or rod mills MOTOR ELECTRO MECHANICAL CHARACTERISTICS The cost of a motor of a Gearless Mill Drive depends mainly on two parameters Diameter of the motor Rated Torque of the motor

    Chat Online
  • Grinding Mills

    SAG mill product feeds two parallel ball mills of 6.6 m 11.1 m internal diameter length each with a 9.7 MW twin pinion drive The ball mills are operated at a ball charge volume of 30–32 and 78.5 critical speed The SAG mill trommel undersize is combined with the ball mills discharge and pumped to two parallel packs clusters of

    Chat Online
  • SAG mill ball charge determination and its influence on

    1990 5 24 In semi autogenous grinding SAG the grinding mill inventory i.e volume of total charge volume of ball charge etc is important in determining the optimum operating condition for maximum production tph minimum specific energy kwh/t or lowest cost /t A two dimensional graphical method is presented for determining the actual ball charge within the total charge when parameters

    Chat Online
  • An electrical impact study between variable speed dual

    2015 10 22 Conventional mining process circuits use both Semi Autogenous Grinding SAG and Ball mills It is very common that the SAG mills are operated with adjustable frequency drives AFDs and the Ball mills are operated at fixed speed 1 Recently however adjustability of Ball mill speed has been given more consideration Also to maximize throughput the Ball mills are sized to be operated at

    Chat Online
  • Grinding Mill Foundations

    2014 9 23 Grinding Mill Foundations admin 23 September 2014 2014 Design Foundations Stiffness System Analysis Vibration Most of our work since 2000 has been in developing grinding mill foundations to avoid vibration and unacceptable deflections On a recent project for a plant in Peru the client was told by the mill vendor that there was no need

    Chat Online
  • 1 x FLS SAG Mill excl

    2019 2 25 2 x FLS Ball Mills excl Motor/Drive For Sale/Re Assignment Mill Details Type of Mill FLS Ball Mills set of 2 Mill Dimensions 7925 x 12344 mm 26 x40 6 Diam x L Default Mill Speed 11.41 RPM Mill Speed 10.65 to 12.17 RPM Liners Metal/RubberExcluded Mill Drive Motor Type Wrap Around GMD Mill Drive Motor Size 16 400 kW 21 993 hp

    Chat Online
  • Wear and Failure Analysis of Semi Autogenous Grinding

    2017 2 27 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 throughput.

    Chat Online
  • Mill Sag Mechanical Failure

    Following the SAG mill will be two 9 000 hp ball mills each one 20 ft in diam and 331/2 ft long that do the finish grinding.How to analyze gear failures EDM speeds cutting of precision gears Right angle gear drivesZero Max Inc.The Essentials of Mechanical Systems.

    Chat Online
  • Finding failure

    2017 9 6 During mill operation roller surfaces wear down which results in a higher dynamic load peaks which exceed the nominal torque and in general an instable mill operation and lower performance In many instances bearing failures at the rolls are caused by excessive dynamics in the grinding process.

    Chat Online
  • SAG mill ball charge determination and its influence on

    1990 5 24 In semi autogenous grinding SAG the grinding mill inventory i.e volume of total charge volume of ball charge etc is important in determining the optimum operating condition for maximum production tph minimum specific energy kwh/t or lowest cost /t A two dimensional graphical method is presented for determining the actual ball charge within the total charge when parameters

    Chat Online
  • Optimizing Performance of SABC Comminution Circuit of

    2017 5 13 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.

    Chat Online
  • Industrial Ball Mills Steel Ball Mills and Lined Ball

    Ball Mills Steel Ball Mills Lined Ball Mills Particle size reduction of materials in a ball mill with the presence of metallic balls or other media dates back to the late 1800 s The basic construction of a ball mill is a cylindrical container with journals at its axis.

    Chat Online
  • Mines Safety Significant Incident Report No

    2021 9 9 A worker was seriously injured during a ball mill relining operation when he was struck by a large liner plate weighing about 1.5 tonnes The worker had been preparing to remove two unsecured liner plates still in place inside the ball mill when the top liner plate was dislodged and fell pinning him to

    Chat Online
  • Frozen charge detection and automatic loosening with

    2021 9 14 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

    Chat Online
  • Optimizing Performance of SABC Comminution Circuit of

    2017 5 13 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.

    Chat Online
  • Major Mines Projects

    The mills operate as parallel lines of one SAG and one ball mil with one line fed from the Fayalala crusher and the other from the Lero Karta crusher It is possible however for either SAG mill to be fed from either crusher and for the circuit to operate with one SAG mill and one or both ball mills offline depending on operating and

    Chat Online
  • An electrical impact study between variable speed dual

    2015 10 22 Conventional mining process circuits use both Semi Autogenous Grinding SAG and Ball mills It is very common that the SAG mills are operated with adjustable frequency drives AFDs and the Ball mills are operated at fixed speed 1 Recently however adjustability of Ball mill speed has been given more consideration Also to maximize throughput the Ball mills are sized to be operated at

    Chat Online
  • Solutions for the mining mineral processing and cement

    2020 12 9 Ball and SAG mill trunnion and gearbox drive systems where lengthy strip down is a costly problem failures SKF provides a sealing solution to replace the standard seals arrangement By using a specially designed seal made of the abrasion resistant H ECOPUR and in

    Chat Online
  • Stepping forward Using variable speed drives for

    2021 10 11 Stepping forward Using variable speed drives for optimising the grinding process in SAG and ball mills ABSTRACT Comminution is usually the heaviest energy consuming process in the mine site These days when efficiency concerns are becoming more and more important developing a reliable and highly efficient way to grind and crush ore is a new

    Chat Online
  • Industrial Solutions polysius ball mills

    2021 9 8 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 For higher drive powers the combiflex gear unit is the unit of choice The combiflex has an output of up to 8 000 kW and with a dual drive

    Chat Online
  • Safe Reliable and Efficient Crushing and Grinding in

    2021 4 16 SAG and Ball mills are one of the most critical pieces of equipment for the process Mining operators need to optimize grinding mill performance and reliability to ensure tight shutoff This process equipment can have unexpected shutdowns and production loss high reprocessing rates high operating costs risks to personnel and the environment

    Chat Online
  • DuraFlex Coupling V Belt Drive

    Dura Flex couplings connect the motor to the speed reducer on ball and sag mills TB Wood s v belt drives are heavily utilized in underground and processing applications including ball sag mills crushers conveyors cooling towers winders and hoists.

    Chat Online
  • RESPONSE OF PRIMARY GRINDING MILL PERFORMANCE

    SAG mill and how the vibration response and hence mill operating conditions vary as a function of time including during mill equipment failures such as a broken discharge grate Opportunities for improved mill control based on the data from the on line monitor are also discussed as well as the implications in terms of mill processing and

    Chat Online
  • Mill drives the desire for increased power and the

    2021 9 11 The standard method for sizing secondary ball mills usually the overflow type in AG/SAG circuits follows published mill supplier information with aspect ratios in the range 1 1.5 to 1 2.0 depending upon product sizing and pulp flow i.e the highest expected circulating loads Morrell 2001 The applied net power calculated from testwork

    Chat Online
  • SmartMill

    Combine ABB s variable speed drive system with advanced process controlABB Ability Expert Optimizer for grindingto provide maximum mill control It can be applied to new or existing AG SAG and ball mills powered by either ring geared mill drives RMD or gearless mill drives GMD .

    Chat Online
  • Finding failure

    2017 9 6 During mill operation roller surfaces wear down which results in a higher dynamic load peaks which exceed the nominal torque and in general an instable mill operation and lower performance In many instances bearing failures at the rolls are caused by excessive dynamics in the grinding process.

    Chat Online
  • Solutions for the mining mineral processing and cement

    2020 12 9 Ball and SAG mill trunnion and gearbox drive systems where lengthy strip down is a costly problem failures SKF provides a sealing solution to replace the standard seals arrangement By using a specially designed seal made of the abrasion resistant H ECOPUR and in

    Chat Online
  • Ball mill high vibs

    Hi Observing high vibs on pressing and lifting pinion DE and NDE bearing on a ball mill Motor and main GB drive are OK Clear predominant gear mesh frequency is appearing in the spectrum along with harmonics and side bands But 1st GMF is predominant side bands with pinion speed is seen no GG speed side band was observed Some of the vib data spectrums and photos shown in the attachment.

    Chat Online
  • Cadia Girth Gear Failures

    2014 9 22 This is an update of work presented at the SAG 2001 conference on the Cadia gears 1 Both gears and pinions on twin ball mills failed almost simultaneously Our 2001 paper showed that the location of the failures is explained by the shape of the girth gear blanks Fresko et al 2 shows that T gears are in fact better than Y gears in terms

    Chat Online
  • BALL MILL GEARBOX PROBLEM

    2019 10 30 BALL MILL DRIVES LOADED WAVEFORM LEVELS SEPTEMBER 1A 1B Above is a plot of the waveform vibration levels at both the 1A 1B ball mills when loaded acceleration Note how waveform levels at 1A ball mill are higher than that at 1B ball mill for every measurement and especially at points PIH PIA pillow block coupling end bearing .

    Chat Online
  • SAG Mill Control It Shouldnt be that Hard

    2010 4 13 SAG mill control fundamentally means managing the load in the mill by adjusting the feed rate of ore to the mill and/or manipulating the rotational speed of the mill The best way to measure load is to mount the mill on load cells The load cells are calibrated to measure the total weight of water grinding media balls and ore in the mill

    Chat Online
  • sag mill ring gear failure

    NEWS RELEASE Kumtor Mine Ball Mill Repair and Centerra Gold Mar 6 2008 SAG mill and regrind mill circuits of the ball mill shell a defect in which is believed to have contributed to the failure of the ring gear mill until a new ring gear can be procured

    Chat Online
  • TECHNICAL NOTES 8 GRINDING R

    2009 7 30 LG A mill power equation for SAG mills Minerals and Metallurgical Processing Feb 1990 pp57 62 Gross power No load power Net power drawn by the charge 8.13 The net power is calculated from Net power KD2.5L e c. Watts 8.14 In equation 8.14 D is the diameter inside the mill liners and Le is the effective length of the mill including the

    Chat Online
  • Grinding Mills Harcliff

    GRINDING MILLS BALL Mills SAG Mills AG Mills ROD Mills We refurbish design and manufacture an extensive range of high quality mills and mill components to exacting standards offering you a turnkey service that s backed by two decades of engineering expertise BROCHURE Finite Element Analysis FEA Ball Charge Trajectory Modelling

    Chat Online
  • Detecting SAG Mill Seal Failures

    2017 3 31 SAG Mills AG Mills Ball Mills Gyratory and Cone Crushers are extensively used throughout the hard rock mining industry In these systems seal leaks leading to water ingression are intermittent and are therefore hard to detect A large Australian gold mine was experiencing problems with detection of seal failures on their large SAG Mill at

    Chat Online
  • SAG MILL DISCHARGE SCREENS TROMMEL vs

    2013 12 22 I ve got to explain this a little bit This flowsheet is typical of lines 1 and 3 The SAG mill has a trommel on the discharge end of it Oversize is returned to the mill by a bucket wheel and water jet Trommel undersize was pumped to a vibrating screen where the screen oversize was sent back to the mill and the undersize was pumped to the

    Chat Online
  • SmartMill

    Combine ABB s variable speed drive system with advanced process controlABB Ability Expert Optimizer for grindingto provide maximum mill control It can be applied to new or existing AG SAG and ball mills powered by either ring geared mill drives RMD or gearless mill drives GMD .

    Chat Online
  • Grinding Mills

    SAG mill product feeds two parallel ball mills of 6.6 m 11.1 m internal diameter length each with a 9.7 MW twin pinion drive The ball mills are operated at a ball charge volume of 30–32 and 78.5 critical speed The SAG mill trommel undersize is combined with the ball mills discharge and pumped to two parallel packs clusters of

    Chat Online
  • Home

    Improve Mill Availability Down Time Production Safety Relining experience AG Mills SAG Mills Ball Mills ROD Mills Our expertise Rubber and steel composite liner change outs Installations Applied manually or with a reliner handler Capacity Singular or multiple mills of any quantity Project Management Independent crew co ordinator appointed to each project.

    Chat Online

Solutions

Products

Project

News