Gearless Mill Drives. Machinery Risk Solutions Practice

Transcription

1 2009 Gearless Mill Drives Machinery Risk Solutions Practice Matt Dugalic P.Eng., MARSH MRSP Risk Consultant, VP Kurt Tischler Dipl.-Ing., Siemens Product Manager, Mining

2 WHY shift to the gearless drives in mineral processing??? Mill size grinding economies of scale Relative lifecycle cost Lower power consumption Robust design Avoiding critical open gear power trains Variable speed Compatibility with processing plants Engineering design efficiencies Availability Minimal downtime Marsh 1

3 However, from the machinery breakdown underwriting perspective, this often creates a critical, single point exposure!!! Marsh 2

4 Significant Mining Industry Property Losses (Jan 2006 Jul 2009) Class Loss Type Gross Claim (MM US$) Coal Flood +/- 603 Coal Flood +/- 550 Coal Flood +/- 450 Iron Storm / Flooding +/- 180 Manganese Smelter Explosion +/- 170 Platinum Flood +/ Iron / Salt Typhoon (Glenda) +/ Copper & Zinc Electrical Flashovers of SAG Mill Stator +/- 115 Iron / Salt Typhoon (Emma) +/ Siemens Marsh 3

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6 SIMINE Mill Gearless Drive Mastertextformat bearbeiten Zweite Ebene Dritte Ebene Vierte Ebene Fünfte Ebene Siemens Gearless Drive Technology Performance Facts & Figures

7 SIMINE Mill Gearless Drive Performance Content Experience & References (5 minutes) Maintenance, Service (2 minutes) Major Problems and their Solutions (25 minutes) Cadia, Repairs, Lessons learned Chilean plant, Rotor failure Performance: Downtime; Availability (10 minutes) Page 2 October 2009 Kurt Tischler

8 SIMINE Mill Gearless Drive Experience First Gearless Drive in Mining Sydvaranger Norway Gearless Drive 8200 kw for a Ballmill of 21.3 ft ID Start-up: 1980 Page 3 October 2009 Kurt Tischler

9 SIMINE Mill Gearless Drive Experience Sydvaranger Norway Gearless Drive 8200 kw for a Ballmill of 21.3 ft ID Start-up: 1980 History: 1997: Shutdown of plant due to low iron prices 2005: Mill and Gearless Drive sold to Zinifex Australia Page 4 October 2009 Kurt Tischler

10 SIMINE Mill Gearless Drive Experience Sydvaranger Norway Gearless Drive 8200 kw for a Ballmill of 21.3 ft ID Start-up: 1980 History: 1997: Shutdown of plant due to low iron prices 2005: Mill and Gearless Drive sold to Zinifex Australia 2008: Restart in Zinifex Century Zinc Plant Page 5 October 2009 Kurt Tischler

11 CODELCO Chuquicamata, 2 GD 8210kW, 32 First Gearless Drives Start-up: 1988 Altitude: 3000 m Page 6 October 2009 Kurt Tischler

12 CODELCO El Teniente, GD kw First 36 Gearless Drive Start-up: 1991 Page 7 October 2009 Kurt Tischler

13 Freeport II; Indonesia, kw First 38 Gearless Drive Start-up: 1997 Altitude: 2700 m Page 8 October 2009 Kurt Tischler

14 Cadia Australia, GD kw, First 40 Gearless Drives Start-up: 1998 Page 9 October 2009 Kurt Tischler

15 SIMINE Mill Gearless Drive References Plant Country Type of Mill ID of Mill (ft) Rated Power (kw) Start-up SYDVARANGER Norway Ball-Mill , CHUQUICAMATA 1 Chile 32 8, CHUQUICAMATA 2 Chile 32 8, EL TENIENTE Chile 36 11, GOLDFIELDS 1 South Africa AG-Mill , GOLDFIELDS 2 South Africa AG-Mill , KENNECOTT USA 36 12, NORILSK NICKEL 1 Russia AG-Mill , NORILSK NICKEL 2 Russia AG-Mill , CANDELARIA 1 Chile 36 12, FREEPORT 1 Indonesia 34 10, ALUMBRERA 1 Argentina 36 13, ALUMBRERA 2 Argentina 36 13, FREEPORT 2 Indonesia 38 20, CANDELARIA 2 Chile 36 12, CADIA Australia 40 20, ANDINA Chile 36 12, OLYMPIC DAM Australia AG-Mill 38 18, PELAMBRES 1 Chile 36 13, PELAMBRES 2 Chile 36 13, Gearless Drives Total Power 233,542 kw Page 10 October 2009 Kurt Tischler

16 SIMINE Mill Gearless Drive References Plant Country Type of Mill ID of Mill (ft) Rated Power (kw) Start-up 20 above 233,542 SAN CRISTOBAL Bolivia 36 13, SAN CRISTOBAL Bolivia Ball-Mill 22 7, SAN CRISTOBAL Bolivia Ball-Mill 22 7, EL TENIENTE Chile 38 19, EL TENIENTE Chile Ball-Mill 24 11, EL TENIENTE Chile Ball-Mill 24 11, EL TENIENTE Chile Ball-Mill 24 11, Barrick Cowal Australia 36 12, Barrick Cowal Australia Ball-Mill 22 10, Equinox Lumwana Zambia 38 18, Equinox Lumwana Zambia Ball-Mill 26 15, RPM Kinross Brazil 38 20, Peñasquito México 38 18,300 Scheduled 2009 Peñasquito México 38 18,300 Scheduled 2010 Los Pelambres Chile 36 15,000 Scheduled 2010 Los Pelambres Chile Ballmill 26 15,500 Scheduled 2010 Las Brisas Venezuela 38 20,000 Project stopped Las Brisas Venezuela 38 20,000 Project stopped ANGLO Los Bronces Chile 40 22,000 Scheduled Gearless Drives Total Power 520,310 kw Page 11 October 2009 Kurt Tischler

17 SIMINE Mill Gearless Drive References Plant Country Type of Mill ID of Mill (ft) Rated Power (kw) Start-up 39 above 520,310 above ANGLO Los Bronces Chile 26 16,400 Scheduled 2011 CP Mining Australia 40 28,000 Scheduled 2009 CP Mining Australia 40 28,000 Scheduled 2009 CP Mining Australia 40 28,000 Scheduled 2010 CP Mining Australia 40 28,000 Scheduled 2010 CP Mining Australia 40 28,000 Scheduled 2010 CP Mining Australia 40 28,000 Scheduled 2010 CP Mining Australia 40 28,000 Scheduled 2011 Xstrata Las Bambas Peru 40 24,000 Scheduled 2011 Xstrata Las Bambas Peru Ballmill 26 16,400 Scheduled 2011 Xstrata Las Bambas Peru Ballmill 26 16,400 Scheduled 2011 Aurox Balla Balla Australia 34 14,000 Project stopped Aurox Balla Balla Australia Ballmill 26 17,000 Project stopped Antamina Peru 38 20,142 Scheduled 2011 Antamina Peru Ballmill 24 11,190 Scheduled 2011 Escondida Chile 40 22,000 Project stopped Escondida Chile Ballmill 26 15,700 Project stopped Escondida Chile Ballmill 26 15,700 Project stopped Escondida Chile Ballmill 26 15,700 Project stopped 58 Gearless Drives Total Power 892,942 kw Page 12 October 2009 Kurt Tischler

18 SIMINE CIS Mill gearless drives References Plant Country Type of Mill ID of Mill (ft) Rated Power (kw) Start-up 58 above 892,942 above Escondida Chile Ballmill 26 15,700 Project stopped Escondida Chile Ballmill 26 15,700 Project stopped Escondida Chile Ballmill 26 15,700 Project stopped Xstrata 2 Peru or Chile 40 24,000 Scheduled 2011 Xstrata 2 Peru or Chile Ballmill 26 16,400 Scheduled 2011 Xstrata 2 Peru or Chile Ballmill 26 16,400 Scheduled 2011 in operation: 33 in fabrication or installation: 21 project stopped: 4 order cancelled: 6 64 Gearless Drives Total Power 1 003,920 kw Page 13 October 2009 Kurt Tischler

19 SIMINE Mill Gearless Drive Clarification No flashovers in Siemens Stators Page 14 October 2009 Kurt Tischler

20 SIMINE Mill Gearless Drive Clarification Collahuasi Chile: 40 Gearless Mill Drive Escondida Chile: 38 Gearless Mill Drive Escondida Chile: 25 Gearless Mill Drives Antamina Peru: 38 Gearless Mill Drive Antamina Peru: 24 Gearless Mill Drives NOT Siemens supply NOT Siemens supply NOT Siemens supply NOT Siemens supply NOT Siemens supply Page 15 October 2009 Kurt Tischler

21 SIMINE Mill GD Experience Number 11 Ball-Mills Xstrada 2 Antapaccay Pelambres Los Bronces Lumwana s Pelambres San Cristobal Cowal Pelambres Andina Alumbrera Candelaria Kennecott El Teniente Goldfields Antamina El Kolskaya San Teniente Cristobal Sydvaranger Cowal Chuquicamata Balla Balla Freeport Antamina Las Brisas Paracatu Peñasquito Lumwana El Teniente Olympic Dam Freeport Xstrada 2 Antapaccay CP-Mining Los Bronces Cadia Mill Diameter Page 16 October 2009 Kurt Tischler

22 SIMINE Mill Gearless Drive Experience Total Operation hours SIMINE Mill GD in Mining: 307 Machine years until September 2009 Page 17 October 2009 Kurt Tischler

23 SIMINE Mill Gearless Drive Experience Total Operation hours SIMINE Mill GD in Mining: 105,000 Machine days until September 2009 Page 18 October 2009 Kurt Tischler

24 SIMINE Mill Gearless Drive Performance Content Experience & References (5 minutes) Maintenance, Service (2 minutes) Major Problems and their Solutions (25 minutes) Cadia, Repairs, Lessons learned Chilean plant, Rotor failure Performance: Downtime; Availability (10 minutes) Page 19 October 2009 Kurt Tischler

25 SIMINE Mill Gearless Drive Maintenance, Service Preventive Maintenance of Gearless Drive is performed during downtime for Mill Maintenance No additional downtime for preventive Maintenance of Gearless Drive Page 20 October 2009 Kurt Tischler

26 SIMINE Mill Gearless Drive Recommended Maintenance Schedule Page 21 October 2009 Kurt Tischler

27 SIMINE Mill Gearless Drive Recommended Maintenance Schedule Preventive maintenance recommended Four (4) actions (in total 13 minutes) once per month, during operation, Eleven (11) actions (in total 247 minutes) once per 3 months, during operation, Two (2) actions (in total 130 minutes) once per 6 months, during downtime for maintenance of mill, 27 actions (in total 25 hours and 46 minutes) once per year, during downtime for maintenance of mill, Five (5) actions (in total 8 hours) once per 3 years, during downtime for maintenance of mill, Five (5) actions (in total 9 hours) once per 5 years, during downtime for maintenance of mill, Page 22 October 2009 Kurt Tischler

28 SIMINE Mill Gearless Drive Maintenance, Service Minimum work for maintenance of Gearless Drive, average of 37 hours per year, Normal electricians and engineers are requested for scheduled maintenance, Siemens offers maintenance and service contracts Page 23 October 2009 Kurt Tischler

29 SIMINE Mill Gearless Drive Performance Content Experience & References (5 minutes) Maintenance, Service (2 minutes) Major Problems and their Solutions (25 minutes) Cadia, Repairs, Lessons learned Chilean plant, Rotor failure Performance: Downtime; Availability (10 minutes) Page 24 October 2009 Kurt Tischler

30 Cadia; Australia Gearless Drive kw for a 40 ft. Observed Phenomena at the Motor of Cadia Commissioning in May 1998 Elastic Deflections During Startup Vibrations during operation Page 25 October 2009 Kurt Tischler

31 Cadia: Investigation P [MW] Resonance frequency of the stator system 20 Rated speed: 9.01 rpm Rated frequency: 6.6 Hz Maximum speed: rpm Max. frequency: 7.6 Hz 10 Operating range 0 7 Hz = 9.5 rpm f [Hz] Page 26 October 2009 Kurt Tischler

32 Cadia: Resonance of the stator system The resonance already appeared during commissioning in July 1998 The problems occurred at cold condition of the motor. Reaching the operation temperature of the Ring motor the vibrations disappeared and the Gearless Drive was operated using the complete speed range Page 27 October 2009 Kurt Tischler

33 Cadia: Resonance of the stator system; PRELIMINARY MEASURES During commissioning stage Siemens provided preliminary measures to enable the operation of Gearless Drive and also at cold condition. Pedestals with hydraulic jacks were installed at the stator bottom to increase stiffness of stator. Page 28 October 2009 Kurt Tischler

34 Cadia: Resonance of the stator system; PRELIMINARY MEASURES The preliminary measures allowed the operation in the complete speed range also in cold condition. The preliminary measures were so successful that Cadia operated the continuously at full throughput. As a consequence Cadia allowed access for investigation only during liner change, six months after start of commercial operation. Page 29 October 2009 Kurt Tischler

35 Cadia: Resonance of the stator system; INVESTIGATION During liner change was performed the deflection measurement taken on the motor of Cadia with photogrammetric system Page 30 October 2009 Kurt Tischler

36 Cadia: Lessons learned Improved FE model, considering non-linear air gap behavior Special airgap elements allow a direct input of excitation current Reaction forces are calculated on deformed structure Stator modeled with beam elements Mill modeled as rigid body on springs Air gap elements Dynamic reaction of structure is calculated with direct time integration Mill stiffness Foundation stiffness Non-linear air gap force vs. deflection relation Page 31 October 2009 Kurt Tischler

37 Cadia: Lessons learned Improved FE model, considering non-linear air gap behavior 3 rd mode shape: Ovalization Page 32 October 2009 Kurt Tischler

38 Cadia: Lessons learned Improved FE model, considering non-linear air gap behavior 4 th mode shape: Twisting Page 33 October 2009 Kurt Tischler

39 Cadia: Repairs Modification of stator Additional stiffener built on the stator Modified form of the stator Page 34 October 2009 Kurt Tischler

40 Cadia: Resonance of the stator system; End of 1999 the stiffener was installed on the stator The installation of the stiffener was performed during a downtime of 7 days parallel to a liner change of five days. Page 35 October 2009 Kurt Tischler

41 Cadia: Resonance of the stator system; Final solution: Stator with stiffener Since installation of the stiffener, end of 1999, the Ring motor of Cadia does not show any vibrations any more. Page 36 October 2009 Kurt Tischler

42 Cadia: Rotor Pole Segments Cracks at support ribs Rotor poles Lamination core Rotor support Rotor flange Mill flange Page 37 October 2009 Kurt Tischler

43 Cadia: Rotor Pole Segments Cracks at support ribs Change of airgap at several spots was detected in The problem was investigated during liner change. Engineering analysis and repair concept was developed by Siemens together with Cadia and EAnD. Cadia published a paper on the SAG-conference 2006 in Vancouver. Please find more details there. Page 38 October 2009 Kurt Tischler

44 Cadia: Rotor Pole Segments Repair Repair was performed during a scheduled downtime of 15 days in June 2005 in parallel to a liner change, which normally needs four days. Page 39 October 2009 Kurt Tischler

45 Cadia Gearless Drive AVAILABILITY Start-up July 1998 to 2003 mechanical & electrical: 98.5 % From 2003 to 2005 electrical: 98.5 % 2005 Repair of rotor electrical: 95.5 % 2005 to date electrical: higher than 99 % Ring motor: 100 % Page 40 October 2009 Kurt Tischler

46 Cadia: Cracks of welding beams at rotor support Design Change Pressure plate Pressure bolt Lamination Weld Flange plate Divided rib Page 41 October 2009 Kurt Tischler

47 Cadia: Cracks of welding beams at rotor support Design Change Stator core Magnetic pull Magnetic pull Tensile Tensile load load Stress concentration Page 42 October 2009 Kurt Tischler

48 Cadia: Cracks of welding beams at rotor support Design Change Magnetic pull Stator core The magnetic pull tries to bend the lamination and the rib welded on to it. Through this a tensile load arises in the lower edge of the rib. Tensile load There is no stress concentration since the rib cross section is undisturbed. Page 43 October 2009 Kurt Tischler

49 Cadia: Cracks of welding beams at rotor support Design Change Design Change was implemented 2005 and is in operation in all Siemens Gearless Drives since then. Page 44 October 2009 Kurt Tischler

50 38 Gearless Mill Drive, Chile Cracked Weld at rotor support The 38 is in operation since September 2003 During the weekend of August 31, 2008 the stopped several times and was restarted. Finally the air gap supervision tripped the motor and did not permit to restart it again on September 1, at 4:48 a.m. Air gap and rotor were revised and there was found a crack of a weld of the rotor segment support (Picture next page) Specialists from Siemens Germany arrived on September 3 at site and investigated the motor. They found another crack at the same segment and another segment with cracks. They started the repair on September 4 and the mill restarted on September 8, 2008 at 9:10 a.m. Page 45 October 2009 Kurt Tischler

51 Chilean Plant Cracked Weld at rotor support Page 46 October 2009 Kurt Tischler

52 Chilean Plant Origin: Fatigue by mechanical stress The mechanical stress is caused by three effects Constant stress by constant magnetic force, (does not cause fatigue) Fatigue is caused by variable stress Variable stress by gravity, Variable stress by changing magnetic force over the circumference, due to air gap deformation Page 47 October 2009 Kurt Tischler

53 Chilean Plant Variable Stress around the circumference Normal air gap deformation during operation Small air gap higher force Large air gap smaller force Page 48 October 2009 Kurt Tischler

54 Chilean Plant Provisional Repair of Rotor Segment Page 49 October 2009 Kurt Tischler

55 Chilean Plant Provisional Repair of Rotor Segment Page 50 October 2009 Kurt Tischler

56 Chilean Plant, Provisional Repair of Rotor Segment Page 51 October 2009 Kurt Tischler

57 Defect of rotor segments; Consequences for other users Siemens investigated the possibility of similar damages in other Ring Motors and informed in September 2008 three other users to inspect the rotors: Other Chilean Plant Inspection was performed during mill maintenance in February 2009: no findings Australian plant Inspections were performed during plant maintenance in November 2008 and February 2009: cracks were found and provisionally repaired; 2 additional days of downtime; Indonesian plant Inspection was performed during plant maintenance in April 2009 cracks were found and provisionally repaired; 12 additional hours of downtime; Page 52 October 2009 Kurt Tischler

58 Chilean Plant Final Repair of Rotor Segment The final repair of the rotor segments were planned from June 30, 2009 to July 14, 2009, parallel to a mill maintenance (liner change). After replacing 4 segments, turning of motor for positioning was interrupted by earth fault. There were found foreign objects in the air gap, which had damaged stator windings and rotor coils. Repair of windings and coils was finished August 10, 2009 without completion of rotor segments. A failure of the feeding switchgear delayed the restart of production for another two days. Caused Downtime: 43 days minus 4 days for mill maintenance Page 53 October 2009 Kurt Tischler

59 SIMINE Mill Gearless Drive Performance Content Experience & References (5 minutes) Maintenance, Service (2 minutes) Major Problems and their Solutions (25 minutes) Cadia, Repairs, Lessons learned Chilean Plant, Rotor failure Performance: Downtime; Availability (10 minutes) Page 54 October 2009 Kurt Tischler

60 SIMINE Mill Gearless Drive Downtime, Availability Major downtimes for repair: Cadia, Vibrations, Cadia, defect at the rotor segments, Chilean Plant, defect at the rotor segments, Australian plant, defect at the rotor segments Indonesian plant, defect at the rotor segments Page 55 October 2009 Kurt Tischler

61 SIMINE Mill Gearless Drive Downtime, Availability Cadia; Vibrations Downtime for repair: 7 days minus 5 days for liner change Cadia; Defect of rotor segments During 2003 Cracks of welds at rotor support were found and provisionally repaired. Downtime: 5 days for investigation and repair minus 4 days for liner change. In 2005 the final repair was performed with a downtime of 15 days. Downtime for repair: 15 days minus 4 days for liner change Page 56 October 2009 Kurt Tischler

62 SIMINE Mill Gearless Drive Downtime, Availability Chilean plant; Defect of rotor segments September 1, 2008 the air gap supervision of the 38 Ring motor tripped the mill. Cracks were detected and provisionally repaired. September 8, 2008 the 38 mill was restarted. 9 days of unscheduled downtime First part of final repair in 2009 including repair of occurred damages: Downtime: 43 days minus 4 days for mill maintenance Scheduled completion of final repair in 2010: Downtime: 15 days minus 4 days for liner change Page 57 October 2009 Kurt Tischler

63 SIMINE Mill Gearless Drive Downtime, Availability Major downtimes for repair: Cadia, Vibrations: 2 days Cadia, defect at the rotor segments: provisional repair: 1 day. final repair: 11 days Chilean plant, defect at the rotor segments: 2008: 9 days First part of repair in including repair of damages 2009: 39 days final repair, scheduled 2010: 11 days Australian plant, defect at the rotor segments: 2009: 2 days final repair, scheduled 2010: 14 days Indonesian plant, defect at rotor segments: 2009: 0.5 days final repair, date to be defined: 10 days Total sum 99.5 days Page 58 October 2009 Kurt Tischler

64 SIMINE Mill Gearless Drive Performance Total Operation hours SIMINE Mill GD in Mining: 105,000 Machine days until September 2009 With major downtimes of in total 99.5 machine days Page 59 October 2009 Kurt Tischler

65 Thank you for your attention! Contact: Kurt Tischler Siemens AG Metals Technologies Mining Industry W-v-Siemens-Str Erlangen / Germany Phone: +49 (9131) Mail: kurt.tischler@siemens.com Page 60 October 2009 Kurt Tischler