RELIABILITY CENTRED MAINTENANCE RCM OFFSHORE CRANES

Transkript

1 RELIABILITY CENTRED MAINTENANCE RCM OFFSHORE CRANES

2 Reliability Centred Maintenance Offshore Cranes Introduction RCM Basic Experiences technical problems & Challenges Maintenance system Jan Ketil Moberg Technical Responsible Engineer Lifting Equipment ConocoPhillips Norway

3 Tananger Regionalt hovedkontor for Europa og Vest-Afrika og for Nordsjøen forretningsenhet. Forsyningsbase for Ekofisk-feltene.

4 Tananger Storbritannia Norge Teesside Eldfisk Embla Tor Ekofisk Oljerørledning Gassrørledning Emden Tyskland Ekofisk-området Det største olje- og gassfeltet på norsk sokkel

5 GEA Infra-structure - Current 2/4 K 2/4 B Ekofisk 2/4 E 2/4 R 2/4 P 2/4 C 2/4 J Tor 2/4 T 2/4 X 2/4 M 2/4 G 2/4 H 2/4 Q 2/4 FTP 2/4 W 2/7 B 2/4 A Embla 2/7 D Eldfisk 2/7 E 2/7 A 2/7 FTP

6 Ekofisk Eldfisk Tor Embla

7 Skal fjernes (to be removed) Ekofisk 2/4 T Ekofisk 2/4 R Ekofisk 2/4 H Ekofisk 2/4 P Ekofisk 2/4 Q Ekofisk 2/4 FTP Ekofisk 2/4 B Ekofisk 2/4 A West Ekofisk 2/4 D Edda 2/7 C Cod 7/11 A Albuskjell 1/6 A Albuskjell 2/4 F 37/4 A 36/22 A

8 Eko A Molde KHOD 3512/0540 Eld FTP Øst Eld E Seatrax 7216 Molde Barriere Vest Molde KHOD 4015/1343 /0845 Eko B Eko J Sør/øst Eko J Nord/vest Eko X Nord Eko X Øst EKoH Molde KHOD 3512/0540 Seatrax 7238L Seatrax 7238R Molde A30D Seatrax 7228 Seatrax 7216 Eld Bravo Vest Eld Bravo Øst B-11 Vest B-11 Øst H-7 Vest H-7 Øst Embla Seatrax 7216 Molde Seatrax 7216 Molde MK60 MK100 Molde KHOD 4015/0842 Eko Kilo Vest Eko Kilo Øst EKOM Tor Øst Eld Alpha Vest Eld Alpha Øst MK100 MK100 Molde C3500L Seatrax 7216 Seatrax 7216 Molde Eko C Øst Molde KHOD 5022/1055 Whisky Molde KHOD offshore cranes split on Eko FTP Vest MK60 13 NOV Moldecrane 9 Seatrax cranes 4 MK cranes

9 Reliability Centred Maintenance Offshore Cranes RCM Basic Maintenance is based on RCM technology and gained experience *) Risk = Probability x consequence **) RCM = Reliability Centered Maintenance

10 Reliability Centred Maintenance Offshore Cranes The goal is to have necessary availability (A) A = MTBF / MTBF + MTBR MTBF = Mean time between failure MTBR= Mean time between repair (included waiting time for spares)

11 Reliability Centred Maintenance Offshore Cranes Reliability, R (t) = Probability for equipment to survive time t (repair to failure) R (t) = e -L t L = 1 / MTBF = Failure rate* Failure rate = Probability for failure pr time (tidsenhet) unit by time t

12 Reliability Centred Maintenance Offshore Cranes Experiences technical problems & Challenges Important experience, some examples: a. Installation of new cranes (8 cranes > 2000) b. Upgrading of king post cranes (9 cranes) c. Upgrading of slew bearing cranes (7 cranes)

13 Reliability Centred Maintenance Offshore Cranes a) Installation of new cranes (8 cranes > 2000) Background: Regulations and cost evaluation Scope of work: New offshore crane in accordance to EN Experience: Need for high skilled maintenance specialist. High regularity, but operational experience has unveiled weaknesses as (examples): Cracks in hand rails (welded aluminium) Flexible couplings Gear wear HVAC system

14 Reliability Centred Maintenance Offshore Cranes Cracks in hand rails (welded aluminium)

15 Reliability Centred Maintenance Offshore Cranes Flexible coupling ca 8500 running hours

16 Pump split gear- wear

17 Reliability Centred Maintenance Offshore Cranes Ventilation system

18 Reliability Centred Maintenance Offshore Cranes b) Upgrading of king post cranes (9 cranes) Background: Working environment Technical problems PSA requirements Low availability Scope: New hydraulic system New swing system New control system (included driver s cabin) New boom sections New winches New top bearing

19 Reliability Centred Maintenance Offshore Cranes Experience: Operational experience Operational experience has unveiled weaknesses within as (examples): Spline connections in winches Wear in top bearing

20 Wear in winch Reliability Centred Maintenance Offshore Cranes

21 Reliability Centred Maintenance Offshore Cranes Incident on EKOC (fall of crane boom):

22 Reliability Centred Maintenance Offshore Cranes

23 Installation of new winches (main,whip and boom)

24 New lifting winches on ELDA New boom winch on Tor

25 Installation of new lifting winches on Tor by using a service crane installed on the boom

26 Reliability Centred Maintenance Offshore Cranes Weakness with top bearing:

27 Pictures of top bearing, ELDA king post crane

28 Reliability Centred Maintenance Offshore Cranes New technical solutions (alternative):

29 Reliability Centred Maintenance Offshore Cranes c) Upgrading of Upgrading of slew bearing cranes Background: Working environment Technical problems PSA requirements Scope: Based on remaining lifetime Experience: Upgraded EKOK west crane on EKOK was a success. This included new engine module, driver s cabin, new winches.

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34 Reliability Centred Maintenance Offshore Cranes Maintenance system Background: Risk evaluation Scope: ConocoPhillips initiated autumn 2004 a project in cooperation with National Oilwell Moldecran for a total RCM evaluation for typical for 2 typical crane models Upgraded King Post Crane New slew bearing crane Experience: Results from the RCM analysis could be used as basis for revision of all offshore cranes. Incident on EKOC (mars 2005) showed the importance with the risk evaluation of components (RCM). In addition, inspection of the split gear on a 2 year old crane unveiled the importance for risk based inspections.

35 Reliability Centred Maintenance Offshore Cranes The RCM analysis is based on the standard SAE JA1011. The criteria of a RCM process is met by the following activities: 1. Listing the functions and their accompanying components in a hierarchy (main functions sub functions components) 2. Carrying out a FMECA* 3. Setting the appropriate maintenance activities for each component The functions in item 1 can be main functions, main components or systems. The hierarchy are similar to the description in Norsok standard Z-008. *) Failure mode effect consequence analysis

36 Reliability Centred Maintenance Offshore Cranes Component failures and criticality : By failure modes usually component failures are meant. Only one failure mode is handled at a time, while all the other equipment is working. And also no maintenance is assumed. The failure rate or frequency is estimated in classes by means of MTBF values (very approximate estimates). The MTBF is the inverse of the frequency. Frequency classes A-C given by MTBF values A >12 years* B 3-12 years C 0-3 years *) 1 Y = 2000 running hours

37 Reliability Centred Maintenance Offshore Cranes The severity of the failure effect especially with respect to safety and operation is given by the consequence. Consequence classes 1-5 given by the severity of the failure effects 1. Normal operation, but irregularities which should be improved within reasonable time 2. Limited operation (finishing the task) 3. Loss of main function (stop of crane) 4. May result in fall of load or boom 5. Fall of load or boom

38 Reliability Centred Maintenance Offshore Cranes The criticality is a function of both consequence and failure frequency, and therefore given by the criticality matrix. Three criticality values are defined, low, medium and high. Criticality matrix Consequence classes Frequency classes A-C given by MTBF values

39 Criticality/ risk matrix The criticality levels low, medium and high (1/L, 2/M and 3/H) is defined by the matrix. Consequence category > 25 1/L MTBF (years) /M /H Curve of acceptable risk (as an example, not agreed upon) Consequence categories 5 Fall of load or fall of boom 4 May result in category 5 3 Loss of main function (stop of crane) 2 Limited operation (finishing the task) 1 Normal operation (except some irregularities) Criticality Maintenance strategy Risk reduction Low Run to failure and cost reduction is the main objective Not required Med Maintenance if benefit > cost or if safety demands it Must be discussed High Improved mainten. or redesign/modification of equipment Must be included

40 No Main sys Sub sys Disc Tag Int ID Description Function Failure mode Failure cause Local effect System effect MTBF (Y) Cons cat 28 Boom hoist Main pump H Luffing pump, shaft/spline Transfer torque from splitter gir to pump Break down Wear, corrosion Oper. stop, load may drop Boom winch 631 Boom winch Drum/ Gear M Spline Transmission between drum and winch gear shaft Fracture No transmission between parts No lifting capasity Gear M Main-gear Torque transmission Fracture Overloaded Winch gear breakdown Drop of boom 5 5 Drop of boom Boom winch 637 Boom winch 638 Boom winch 639 Boom winch 644 Boom winch Mech M Fastening point Connect the winch to the structure Mech M Fastening point Connect the winch to the structure Motor M Spline Transmission between motor and brake Motor M Spline Transmission between brake and gear Rope M Socket Connects the wire to the boom Bolt losing pretensioning. Overloaded Fracture Fracture Reduction of the load carrying capacity Failure when tension the bolts. Fracture of the bolt No transmission between parts No transmission between parts Critical deformasion on the structure. Reduction of the mechanical strenght No lifting capasity No lifting capasity The winch can stop working. 5 4 Drop of boom 5 4 Drop of boom 5 4 Drop of boom 5 4 Fracture Drop of load Drop of boom 10 5

41 Reliability Centred Maintenance Offshore Cranes More than 800 components for each crane model have been evaluated

42 Reliability Centred Maintenance Offshore Cranes Typical new standards which have been developed as result of the RCM analysis: High Criticality (examples) Winches: Spline inspections (for one and two motors) Winch foundations Revised oil analysis Split gear: Spline inspections Revised oil analysis Boom: Extended structural inspections Wire: Extended inspection Replacement program

43 Reliability Centred Maintenance Offshore Cranes medium Criticality (examples) Swing system: Swing motors Diesel motor: Flexible coupling Top Bearing King Post cranes: Extended inspections PLS system: Extended inspections & tests Hydraulic system: Heating elements

44 Reliability Centred Maintenance Offshore Cranes Low Criticality (example) Electrical system: Switches

45 Plattform / Plassering; Eko J Sør/øst Eko J Nord/vest Eko X Øst EKoH Eko C Vest Tor Øst Kran Fabrikant / Modell; Seatrax 7238L Seatrax 7238R Seatrax 7228 Seatrax 7216 Seatrax 7216 Seatrax 7216 Kategori; Nr.; Eq. / Tag; B A (4Y) WS-19KRAN130.M Splineforbindeler for vinsjarrangement - 1 motor (Molde vinsjer) Maintenance Item; N/A N/A N/A BD/EKOH/00061 Task list; N/A N/A N/A G: 19DCRA GC: 74 Work Standard nr.; N/A N/A N/A BD/WS-19KRAN130.M Work Standard Tittel; N/A N/A N/A SAP Implementerings status; N/A N/A N/A Splineforbindelser for vinsjarrangement - 1 motor (Molde vinsjer) WS-19kran130.M implementert i OpAc WS- 19kran127.M slettet. Lagt inn timer / insp. Intervall Preservert - uavklart mht oppgradering av vinsjer og videre bruk Preservert - uavklart mht oppgradering av vinsjer og videre bruk Preservert - uavklart mht oppgradering av vinsjer og videre bruk Preservert - uavklart mht oppgradering av vinsjer og videre bruk Preservert - uavklart mht oppgradering av vinsjer og videre bruk BD/TOR/00563 G: 19DCRA GC: 19 BD/WS-19KRAN130.M Splineforbindelser for vinsjarrangement - 1 motor (Molde vinsjer) WS-19kran130.M implementert i OpAc WS- 19kran127.M slettet. Lagt inn timer / insp. Intervall es - Inspeksjon 2 (4Y) WS-19KRAN131.M Splineforbindeler for vinsjarrangement - 2 motorer (Molde vinsjer) Maintenance Item; N/A N/A N/A N/A Task list; N/A N/A N/A N/A Work Standard nr.; N/A N/A N/A N/A Work Standard Tittel; N/A N/A N/A N/A SAP Implementerings status; N/A N/A N/A N/A Preservert - uavklart mht oppgradering av vinsjer og videre bruk Preservert - uavklart mht oppgradering av vinsjer og videre bruk Preservert - uavklart mht oppgradering av vinsjer og videre bruk Preservert - uavklart mht oppgradering av vinsjer og videre bruk Preservert - uavklart mht oppgradering av vinsjer og videre bruk N/A N/A N/A N/A N/A

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47 Reliability Centred Maintenance Offshore Cranes Summarize -RCM analyse: Gap analyse of the RCM and existing maintenance maintenance program showed gaps Unveiled GAP between RCM and manufacturers proposed maintenance program ConocoPhillips initiated revision of the maintenance program based on the RCM program. Involved manufacturer, maintenance personnel and verification body Added > 6400 hours/year (expanded the maintenance program) Revised the spare part system (critical components) Crane specialists from manufacturer on fixed offshore schedule Continuous need for verification and adjusting of the maintenance program based on gained experiences

48 Sikkerhet og miljø Arbeidet er aldri så viktig eller haster så mye, at vi ikke har tid til å gjøre det sikkert. Vi setter spesifikke sikkerhets-, helse- og miljømessige mål for alle våre aktiviteter og vi anstrenger oss hele tiden for å forbedre vårt prestasjonsnivå. Miljøet vi opererer i gjør vår forpliktelse til en bærekraftig utvikling til en vesentlig strategi for ConocoPhillips.

49 Takk for oppmerksomheten! Thanks for the attention!