State of the art on condition based monitoring concepts

5/24/2018 State of the art on condition based monitoring concepts.

http:///reader/full/state-of-the-art-on-condition-based-monitoring-concept

WCM-IP

Workpack 2Task 4step 4.

Authors: Geert Henk Wijnants; John Marinus Page 1 10-Jan-12

World Class Maintenance Innovation projects(WCM-IP)

FINAL

Survey of State of the Art with respect to conditionmonitoring concepts.

Report task 4 step 4.

Workpackage # 2

Author(s): Geert Henk Wijnants, John MarinusOrganization: Stork Technical Services.Report date: Dec 23rd, 2011



WCM-IP



1 Summary

On behalf of the task of describing the status quo of condition monitoring (CM) within theDutch Industry, a questionnaire has been sent in order to assess the current level ofapplication of condition monitoring concepts.In order to safeguard that a broad range of Dutch Industry has been reached, the nextcontact channels have been used subsequently: the openWCMwebsite, theNVDOmembers website (appr.1700 members), a mailing to about 560 recipients from 420 differentcompanies who have been selected based on their function profile and finally by means of apresentation to an audience of about 40 people withinAMCcentre(Asset ManagementControl Centre) context.In order to check the clarity of the information sent, in 5 cases addressed persons have beencontacted in order to check for their response.This effort has resulted in 19 surveys that have been filled in and returned.

The answers to the various questions have been scored and ranked on a score list varyingon a scale from 1-10 in order to assess the various answers in a systematic way. Since thereare various angles of perception for a specific answer, 5 different angles have been selectedrespectively: Level of organization, Technical development, Analytical development, Use ofexpertise and cost-efficiency.

The various scores and the overall response have led to the next findings:

With respect to the tool and format used for the given goal:

Surveys of this type appear to have a poor effectiveness

Other tools for executing surveys are considered more effective, such as web-basedmaintenance fora, round table sessions and direct surveys during conferences.

With respect to the answers obtained:

The number of responses is far below the amount of 125 responses that was defined asa representative number. Therefore the current result should be considered indicative.

The amount of experience with CM is normally 10 yrs or longer.

The majority of the state of the art applications refers to bearing and wall thicknessmeasurements

The overall rating by the 5 angles of perception lie in the range 6-7 which is adequate.

There is no specific sector within industry that scores better than others. For one type ofindustry the ratings vary in between the extreme scores. In general for infrastructure thescores are on the low range, the highest ratings are obtained in the petrochemical

industry, yet all still above 6 so adequate. The majority of responses identify a need for specific developments in order to leverage

the application of CM to a higher level. 30% identifies a joint knowledge development assuch.

When considering CM as a process within asset management rather than a separateactivity, various factors all require at least a level good. The majority of responsescontain gaps which lead to ineffectiviness in the overall approach. Yet 5 responses scorean overall effectiveness that represents 90% of the maximum attainable which can beconsidered quite good.

With respect to the level of development of CM in comparison to the WCM-Reference model:

Most CM is focused onto determining whether the current condition is still acceptable(checking role) rather than being focused onto what future performance is likely to be(predictive role).
http://www.worldclassmaintenance.com/index.php?option=com_content&view=article&id=240:medewerking-gevraagd-&catid=45:nieuwshttp://www.worldclassmaintenance.com/index.php?option=com_content&view=article&id=240:medewerking-gevraagd-&catid=45:nieuwshttp://www.worldclassmaintenance.com/index.php?option=com_content&view=article&id=240:medewerking-gevraagd-&catid=45:nieuwshttp://www.nvdo.nl/http://www.nvdo.nl/http://www.nvdo.nl/http://www.amccentre.nl/http://www.amccentre.nl/http://www.amccentre.nl/http://www.amccentre.nl/http://www.nvdo.nl/http://www.worldclassmaintenance.com/index.php?option=com_content&view=article&id=240:medewerking-gevraagd-&catid=45:nieuws



WCM-IP



2 Terms of reference

Introduction.The projectplan for WCM task condition monitoring contains the taskAssessing the state of the art with respect to condition monitoring by means of a

questionnaire within Dutch industry. Since Dutch industry and the state of the art arebroad concepts, the next references have been introduced: Dutch industry is interpreted by means of 5 sectors as discriminated by Profion inRef. 1.

This also covers the civil infrastructure sector.

The state of the art is perceived by means of the characteristics of a conditionmonitoring (CM) as discerned by the WCM CM reference model, which is based onRef.

5.The checklist for designing a complete condition monitoring approach has beencondensed onto a lite version which is used as a more comprehensive tool to assessthe status of CM within industry.

In this framework a state of the art implementation of condition monitoring is consideredan overall process in which CM acts as a trigger for activities, rather than an isolated

activity in which measurement are done and reports are delivered.

Alike the structure ofRef. 5,questions have grouped into focus areas such as datainterpretation, supporting tools and organization as well as phases during the CM lifecycle such as preparation, measuring, reporting and advice as well as evaluation/end of

life by means of a cost and benefit assessment.

The draft versions of the questionnaire have been tried out with Bosch Rexroth, at TUTwente and has been discussed with Nedtrain, in order to make sure that both time

expenditure is acceptable (max. 1 hr.) and the questions are clear (these try-outs outhave been excluded from this report).

The number of required responses in order to deliver a representative result, is defined

as 125 based on about 25 responses per sector, for which a mailing size of 500 isconsidered sufficient based on an a guesstimated 25% response.

3 Mailing.

Target group:The mailing has focused onto people involved in maintenance management,maintenance engineering and inspection, since these are the disciplines that likewise haveresponsibility with respect to the effective application of condition monitoring within themaintenance process.In order to pronounce the importance of the questionnaire, an recommendatory note hasbeen written by Lex Besselink, WCM director, which has been appended to the Email.

Distribution of the questionnaire has been executed in the following ways: The mailing list is defined by means of a selection by the task force of 19 known CM

users, to which an address list has been added that has been filtered on people that aredirectly related (based on their function description) to the implementation of

maintenance tasks. This resulted in a mailing that has effectively reached 561 email

addresses. The Email has also been published on the WorldClassMaintenance site with a link to the

accompanying Excel questionnaire.

A general call for participation referring to the WCM site has been published by Lex

Besselink by means of a discussion on the Linkedin World Class Maintenance group.

NVDO has been willing to publish the Excel questionnaire on the website for theirmembers. By this manner the approximately 1700 members of this maintenance societyshould be able to participate in the questionnaire.

During a presentation on the AMC Centre on Nov. 3rd the audience of about 40 people

has been informed about the questionnaire and has been asked for their participation. At least 5 persons have been contacted personally in order to ask for their response. This

has been done in order to check on the priority that is given on questionnaires like this.



WCM-IP



The ultimate limit for the questionnaire has been set to the end of November 2011. Yetresults returned within revision time for this report have been included.

4 Approach.

Explanation on the process of gathering information and assessing the available material: The results of the questionnaires have been evaluated as follows:All questionnaires are imported into one database, in which company information isexcluded. Reference for the sender of a questionnaire is made by including the date and timeof reception of the Email in the listing as well as the date&time stamp on which the file waslast saved. This should enable everyone to retrieve his/her own response and rating amidstthe other responses.The answers on the various questions are assessed by assessing the answers through 5different perceptions (views) with respect to the specific CM application:

Development of organization

Development of CM method Analytical development

Use of company specific experience (with respect to the method)

Evaluation of cost efficiencyWhen there is a relation between one of the views than that answer is related to a score.The different possible answers are rated on a scale from 1-10 which are alike report notes.So a 10 is excellent, a 6 is adequate and a 1 is beyond all limits.Since there is no template for good or bad, in practice scores range from 4 to 8.Only when a specific answer is obviously deviating, a lower or higher score is possible.Such a situation occurs when one answers that the state of the art CBM technique clearlyfails to meet the expectations (why then is it state of the arts?). This results in a 3 score.The scores are processed in two manners:

As an absolute score (abs).

As the percentage of maximum achievable on that anwer (rel).

The resulting scores are grouped into an overall score in two ways:a) Averaging:Assessing the average of the abs answers-scores per viewb) Product series:Combining the rel percentages into one product figure. This implies

that low scores in specific aspects can reduce the overall score. This implies that alow score can highlight specific aspects that can be hidden in an averaged figure.Since the product of up to 66 answers can easily lead to for instance 0,966so an very

small number (10-3), the 10 Log of this figure is taken for comparison purposes.These assessing methods are illustrated by the next examples in which:

The Maxmentioned are the maximum scores that can be attained for a specific question.The 2ndrow represents either a code for a column or the way how a column is calculated

by means of other columns.

Answer 1 Score 1(Max = 8)

Answer 2 Score 2(Max =9)

%Score 1 %Score 2 a)Average

b)Product series

A B C D E F Average(B,D) E*F

Yes 8 Average 6 100% 66% 7 66%

No 4 Poor 3 50% 33% 3,5 16,5%



WCM-IP



5 Result.

On a total of at least 600 requests for input, 19 filled in questionnaires have beenobtained.

The personal contact revealed that in general the subject was considered as being ofinterest. To give response was considered as being low on the priority list, thequestionnaire had been forgotten or questionnaire fatigue was present.

The questionnaire results in a poor response. This does not necessarily imply there is nointerest for the subject. Yet it is clear that the questionnaire tool is ineffective for thecurrent purpose.

The responses received reflect that personal involvement with the subject is aprerequisite in order to take part in the questionnaire.

No common relationship has been found between the type of activities that a person isrelated to and affinity with the subject..

Given the poor response the results can only be regarded as indicative for the currentstate of the art with respect to CM. The response is too small to discriminate between

various sectors. Assessment of the questions resulted in the next overviews:

Overall score.Average score of responses on the 5 views

Process score,the 10Log of the product of percentual score

per subject.Note: the color scale is set per view (column)since the amount of aspects that are

combined varies per column.



WCM-IP



The organisations from the various series are distributed as seen in the following table:

Series: Sector: Organisation size:

Series 1 (Petro-)Chemical 10- 100 Incl. contracting

Series 2 (Petro-)Chemical 10- 100

Series 3 Infrastructure (rail, road- and waterway construction) -

Series 4 Infrastructure (rail, road- and waterway construction) 10- 100

Series 5 Manufactering industry > 1000

Series 6 Rail > 1000

Series 7 ..other.., see 10- 100


Series 9 Food 10- 100

Series 10 (Petro-)Chemical > 1000Series 11 Manufactering industry 10- 100

Series 12 (Petro-)Chemical < 10

Series 13 Voedingsmiddelen 10-100

Series 14 - -

Series 15 Manufactering industry < 10


Series 17 (Petro-)Chemical < 10

Series 18 Energy(Electricity/Gas) > 1000

Series 19 Waterkwaliteitsbeheer 10- 100

6 Conclusions.

With respect to the answers obtained:

The number of responses is by far not the amount of 125 responses that was defined asa representative number. Therefore the current result should be considered indicative.

The amount of experience with CM is normally 10 yrs or longer.

The majority of the state of the art applications refers to bearing and wall thicknessmeasurements

The majority of responses identify a need for specific developments in order to leveragethe application of CM to a higher level. 30% identifies a joint knowledge development assuch.

Most CM is focused onto determining whether the current condition is still acceptable(checking role) rather than being focused onto what future performance is likely to be(predictive role).



WCM-IP



With respect to the views obtained as a result on the questionnaires: The two different approaches ( a)averaging and b) product series) with the various views

to assess the questionnaires, provide comparable results when combined to the level of aview.

The overall view a) rating by the 5 angles of perception lie in the range 6-7 which isadequate.

There is no specific sector within industry that scores better than others. For one type ofindustry the ratings vary in between the extreme scores. In general lower ratings havebeen scored for infrastructure while the highest ratings apply to the petrochemicalindustry, yet all still above 6 so adequate.

The variation in scores within one type of Industry comply with findings within other WCMstudies so far, for which it was stated that there are somewhat isolated front-runningcompanies which are not representative for their branch of industry in general.

The variety of scores for the product series assessment reveal that there is a tendencyfor poorer scores when stepping subsequently from view Organisation to Technical

development, Analytical development through Use of experience to cost effectivity.This is indicative for a process in which attention is primarily focused onto executionwhilst the overall cost-effectiveness of the process gets obscured.

Due to the variety in levels of application of CM within the same type of industry, it can beconcluded that clear efficiency and cost effectiveness advantages can be achieved byaligning the implementation processes for CM.

Using the product series assessment b). when considering CM as a process within assetmanagement rather than a separate activity, various factors all require at least a levelgood. The majority of responses contain gaps which lead to ineffectiveness in theoverall approach (a low score). Yet 5 responses score an overall effectiveness thatrepresents 90% of the maximum attainable which can be considered quite good.

With respect to the questionnaire tool and format used:

This survey appears to have a low effectiveness for which the next successiveexplanations have been found:

a) surveys have a low priority compared with other tasks that are directly task related.b) there is a specific survey fatigue since nowadays a multiplicity of surveys is

distributed.

c) when going more into depth, the time required for this type of questionnaires presentsa considerable barrier for the response

d) the reward for sending in the survey is not clear

Other tools for executing surveys are considered more effective, such as web-basedmaintenance fora, round table sessions and direct surveys during conferences.

Although the questionnaire response is poor, it is worth considering continuation of the

questionnaire cycle on a yearly basis. Yearly gathered responses related to a yearlyupdate of the type the 2011 Dutch CM State of the artby WCMis likely to be of interestfor the specific group that sees clear benefits of improving their CM approach.

Development of a specific WCM State of the art Assessment tool is worthwhileconsidering . Attractive functionality would be achieved when registered users can fill intheir findings with a) immediate reward by means of feedback of the score incomparison to other scores and b) direct advises for improvements, based oncomparison with other companies. Initiatives for improvement could be leveraged to ahigher level since arguments for improving the current asset management situation canbe provided by the tool.

It seems worthwhile to highlite risk assessment either in a separate survey or within thisCM survey since this provides the guiding principle for all types of maintenance tasks (soalso CM) whilst interpretation of the actual risks present vary widely when no commonframework is applied.



WCM-IP



References.Ref. 1. Inventarisatie van de branche industriel onderhoud 2005-2006. November 2006.

Profion.Ref. 2. Guidelines for Condition Based Maintenance, Version 1.8, Jan 12 2010. Tinga,

Souters, Roeterink. Editor: World Class Maintenance.

Ref. 3. Workinstruction checklist HERMES. G.H. Wijnants; P. Hlscher. Delftclusterpublication nr. 01.01.07-09, Feb 2003.

Ref. 4. A Framework for Condition Monitoring and Condition Based Maintenance. P. A.

Scarf. Quality Technology & Quantitative Management Vol. 4, No. 2, pp. 301-312,

2007Ref. 5. HerMes: The rational monitoring evaluation system. Final report. P. Hlscher,

G.H. Wijnants. Delftcluster report 01.01.07-10. Feb. 2003.



WCM-IP



7 Appendix. Survey.



WCM-IP



Documents

State of the art on condition based monitoring concepts