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Condition based maintenance with M2M Bigdata Analytics

By on September 17, 2013

Manufacturers and operators employ array of maintenance strategies, all of which can be broadly categorized as below:

  • Corrective Maintenance
  • Preventive Maintenance
  • Predictive Maintenance

Corrective maintenance is the classic Run-to-Failure reactive maintenance that has no special maintenance plan in place. The machine is assumed to be fit unless proven otherwise.

  • Cons:
    • High risk of collateral damage and secondary failure
    • High production downtime
    • Overtime labor and high cost of spare parts
  • Pros:
    • Machines are not over-maintained
    • No overhead of condition monitoring or planning costs

Preventive maintenance (PM) is the popular periodic maintenance strategy that is actively employed by all manufacturers and operators in the industry today. An optimal breakdown window is pre-calculated (at the time of component design or installation, based on a wide range of models describing the degradation process of equipment, cost structure and admissible maintenance etc.), and a preventive maintenance schedule is laid out. Maintenance is carried-out on those periodic intervals, assuming that the machine is going to break otherwise.

  • Cons:
    • Calendar-based maintenance: Machines are repaired when there are no faults
    • There will still be unscheduled breakdowns
  • Pros:
    • Fewer catastrophic failures and lesser collateral damage
    • Greater control over spare-parts and inventory
    • Maintenance is performed in controlled manner, with a rough estimate of costs well-known ahead of time

Predictive Maintenance (PdM) is an alternative to the above two that employs predictive analytics over real-time data collected (streamed) from parts of the machine to a centralized processor that detects variations in the functional parameters and detects anomalies that can potentially lead to breakdowns. The real-time nature of the analytics helps identify the functional breakdowns long before they happen but soon after their potential cause arises.

  • Pros:
    • Unexpected breakdown is reduced or even completely eliminated
    • Parts are ordered when needed and maintenance performed when convenient
    • Equipment life and there by its utilization is maximized
  • Cons:
    • Investment costs for implementing the condition-based monitoring (CBM) system
    • Additional skills might be required to effectively use the CBM system effectively

Predictive maintenance, also known as Condition Based Maintenance (CBM) differs from preventive maintenance by basing maintenance need on the actual condition of the machine rather than on some preset schedule or assumptions.

For example, a typical preventive maintenance strategy demands automobile operators to change the engine oil after every 3,000 to 5,000 Miles traveled. No concern is given to the actual condition of vehicle or performance capability of the oil. If on the other hand, the operator has some way of knowing or somehow measuring the actual condition of the vehicle and the oil lubrication properties, he/she gains the potential to extend the vehicle usage and postpone oil change until the vehicle has traveled 10,000 Miles, or perhaps pre-pone the oil change in case of any abnormality.

Underlying preventive maintenance is the popular belief that machine failures are directly related to machine operating age, which studies indicate not to be true always. Failures are not always linear in nature. Studies indicate that 89% of the problems are random with no direct relation to the age. Table 1 showcases some of these well-known failure patterns and their conditional probability (Y-axis) with respect to Time (X-axis).

FailurePattern

Fig: Failure Probability Curves

Complex items frequently demonstrate some infant mortality, after which their failure probability either increases gradually or remains constant, and a marked wear-out age is not common. Considering this fact, the chance of a preventive maintenance avoiding a potential failure is low, as there is every possibility that the system can fail right after a scheduled maintenance. Thus, preventive maintenance imposes additional costs of repair. Predictive Maintenance reduces such additional costs by scheduling maintenance if and only when a potential breakdown symptom is identified.

However, the costs of monitoring equipment and monitoring operations should not exceed the original asset replacement costs; lest the whole point of Predictive Maintenance becomes moot. Studies have estimated that a properly functioning CBM program can provide savings of 8% to 12% over the traditional maintenance schemes. Our customer reports indicate the following industrial average savings resulted from initiation of a functional predictive maintenance program:

  • Reduction in maintenance costs: 25% to 30%
  • Elimination of breakdowns: 70% to 75%
  • Reduction in equipment or process downtime: 35% to 45%
  • Increase in production: 20% to 25%

Predictive analytics with M2M telematics provides deep insights into the machine operations and full functionality status – giving rise to optimal maintenance schedules with improved machine availability. The enormous data streamed in realtime from sensors attached to the machine/vehicle is processed with big data architectures to enable anomaly detection and failure prediction in real time.

The demo video below showcases the Predictive Maintenance in operation with an electric locomotive airbrake as M2M predictive analytics case study. It demonstrates computing the Failure rate and MTTF from realtime operating conditions, and how alternate scenarios can be evaluated for a what-if analysis that can benefit from big data architectures.

More details can be found in my M2M Telematics & Predictive Analytics paper.

About Author:

Gopalakrishna Palem is a Technology Management & Strategy constultant specialized in Big data architectures and M2M predictive analytics. During his 12+ year tenure at Microsoft and Oracle, he helped many customers build their high volume transactional systems, distributed render pipelines, advanced visualization & modeling tools, real-time dataflow dependency-graph architectures, and Single-sign-on implementations for M2M telematics.

When he is not busy working, he is actively engaged in driving open-source efforts and guiding researchers on Algorithmic Information Theory, Systems Control and Automata, Poincare recurrences for finite-state machines, Knowledge modeling in data-dependent systems and Natural Language Processing.

He can be reached at [email protected]

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There Are 35 Comments

  1. Rahul yadav says:

    Respected Sir,
    Sir ITI Praivate College Se kre Ya Regular College se kre,
    Plese Answer.

  2. ITI pass fitter 2years exp &apprentice 8757230208

  3. RISHIRAJ says:

    I injured my leg was operated on but I have never been to the matter So it will have any effect on the time of medical? If i want become alp. Plz tell me sir

    • RISHIRAJ says:

      Plz reply us i waiting a long time plz reply me

      • Mahesh Kumar Jain says:

        I will not be able to comment about the medical issue. As regards books, I am working on an article to assist the way one should prepare. The examination will certainly be one year later and in the mean time, study your books of class IX and X for general science, class VI to VII for mathematics.

  4. RISHIRAJ says:

    Suggest book for alp

  5. kusum kumar says:

    Good morning sir
    I have a problem please help
    Mera selection group D post pe Rrc Jaipur se hua h. Iski joining dipavali tak aane ki kah rahe h. And Sir mere Delhi police head constable me 95% chances h selection ke jiska result February tak aayega or joining final result aane ke bad minimum 10 days me karni jaruri h nhi to post cancelled ho jati h.
    Sir m ab group d join kar rha hu. Agar Delhi police me selection ho jata h to group D ko leave kar dunga.
    Dear sir what is the process to leave group D and join a new post

  6. Ashraf says:

    Sir i have glasses of number 0.75 and 1.75 both of both eyes i m in 12th science now and its always my dream to become an alp m i eligible if not what can i do and why i am not eligible due to my eyes or my studies? Ans fast

  7. Ashraf says:

    But what if i do laser treatment and come my eyes at normal vision then i think railway will accept me right? Please reply fast..

  8. Ashraf says:

    Isnt therr anyway that can make my dream come true please help

  9. Ashraf says:

    Ok just tellme if a do b. Sc with physical then it is applicable for alp job too na?

  10. vipul shrma says:

    sir i have only btech (ece) degree.and called for document verification for alp.
    i am getting worry about eligibility.
    eligible or not please help me

    • Mahesh Kumar Jain says:

      Why you are getting worried about eligibility. You possess the qualification more than required. In fact you will find difficulty to adjust yourself in the environment on joining with the other candidates possessing much less educational qualification. But once decided, forget to regret and enjoy every moment of training and further job experience.

      • vipul shrma says:

        infactly i am geteing worried about the demand of electronics engineer in place of electronics and communication engineering which i have possess. actually i have called in rrb board about this problem he said that u are not eligible thats why i am woried please give me perfect solution.

        • Mahesh Kumar Jain says:

          There in authenticity of what is said over phone. You should ignore it. Electronics or any other branch with electronics as the central branch shall be acceptable. This is but natural. I don’t think you should be worried and have your confidence in place.

  11. sundarraj says:

    I am waiting .12th,ITI mechanic diesel complete

  12. Anugrah Chauhan says:

    Dear sir,My document verification is 25oct in mumbai but sir I lost my both call letter written and psycho test I have only DV call letter. Sir please suggest what I do. I am very depressed. Sir please tell me is there any problem without that call letter
    Tel:-9891001966

    • Mahesh Kumar Jain says:

      It should not be a big issue. You produce your document based on DV letter. In any case, if you have lost it, FIR shall help or if it is not tracable not nothing can be done.

  13. surendhar says:

    Sir I’m doning present diploma EEE..can I get ALP in railways…

  14. Ajith says:

    sir, i have completed my 12th education(science) what is the next step that i should do to become a locopilot.

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