RIMAP (RISK BASED INSPECTION ANDMAINENANCE FOR EUROPEAN INDUSTRIES) THE EUROPEAN APPROACH Sture Angelsen (DNV) – Mikael Johansson (DNV) – Alasdair Pollock (Corus) – Gjermund Våge (DNV) Key words: risk, maintenance, inspection ABSTRACT This paper presents an overview of the European project RIMAP (Risk Based Inspection and MAintenance Procedures for European industries). The paper also provides a short review of the results from the demonstration case in the steel industry. INTRODUCTION Current practice to inspection and maintenance planning is for most industries based on tradition and prescriptive rules, rather than being an optimized process where risk measures for safety and economy are integrated. New technology for taking risk based decisions is emerging in a broad range of sectors, and they have proven to be a very efficient tool (Fig. 1). There is, however, a great need to define the technical content, links to local legislation and to integrate this approach with the day-to-day operation of the plants. Profitability Long term goal Integration of tools & best practice Short term goals Previous practice Detailed requirements: • owner own and • authorities requirements Past regime Excellence: plant lifetime Best practices and analysis tools: • risk based inspection (RBI) • reliability centred maintenance (RCM) • life cycle cost Current Future Fig. 1 RIMAP objective to develop a unified approach to risk based decisions within inspection and maintenance. This is the background for the RIMAP project, where a consortium of 16 European companies representing a broad industry base have joined forces to develop a European best practice and to demonstrate its applicability in several case studies. The project addresses the petrochemical, chemical, steel works and the power industry in particular, but the techniques can easily be extended and used in other industry sectors as well. 2). within the field of inspection and maintenance (Fig. Risk is here understood as the combined effect of the probability of failure and the consequence of failure (to personnel safety. Wanted situation: Current Status: • Prescriptive rules • No accepted standard • Old plants • Cost constrain for investment • Cost optimised plants • Safe and reliable operations • Extended lifetime of old plants • Enhanced competitiveness • Uniform legislation in Europe Means: • Structured risk based decisions process • Use of modern risk analysis tools • Standardisation of methods for RBMI • Development of best practice • Experience transfer between industry sectors • Damage model development Fig. and tools • form the basis for future standardization in this area. which is a standard for design and construction of pressure equipment. The EU has no similar standard for the in-service phase. The EU has recently introduced the pressure equipment directive (PED). The RIMAP project will develop the technological basis for a standard for risk based maintenance and inspection planning (RBMI). quality of product. and economic loss). 2 RIMAP objective to develop a unified approach to risk based decisions within inspection and maintenance.The objective of the project is to define a unified approach to making risk based decisions. personnel qualifications. The RIMAP project has • developed a unified approach to risk based inspection and maintenance planning • set requirements to the contents of an analysis. environmental damage. . . The RTD/ DEMO projects will be completed in 2004. The project is divided into three sub-projects: • RTD (Research and Technology Development) • DEMO (Demonstration for each industry sector) • TN (Thematic Network) The RIMAP RTD/DEMO/TN projects started in 2001. based on a multi-criteria decision process. The WP's are structured with a clearly defined interrelation in order to achieve an efficient execution of the project. steel. Workshop on utilisation of methods Discuss revised methods Exchange of experience. damage models for participating industry sectors. WP3: Development of detailed risk assessment methods. the RIMAP Demo and the interaction with the RIMAP Thematic Network. industries •User requirements WP5: Validation and comparison RTD WP2: Generic Method Demo: chemical.. • Chemical and • Steel. power. WP5: Validation of the RIMAP methodology. see Fig. • Petrochemical.RIMAP (RISK BASED INSPECTION AND MAINTENANCE PROCEDURES FOR EUROPEAN INDUSTY) Project Overview Risk Based Inspection and Maintenance Procedures for European Industry (RIMAP) is a European project that shall develop a unified approach for making risk based decisions within inspection and maintenance. The focused industries are: • Power. while the RIMAP TN will be completed in 2005. WP4: Development of RIMAP application workbooks for each industry sector: guidelines for development of Risk Based Inspection and Maintenance plans. WP2: Development of a generic RBMI method. 3 Relationship between the RIMAP RTD WPs. . • • • • • WP1: Current practice within the involved industries. the use of inspection data. RIMAP WP-relations Update on RBMI WP3: Risk Assessment Methods WP4: RIMAP Application Workbooks •State of practice from inv. The RIMAP RTD project is divided in 5 main technical work packages (WP). 3. Recommendations Standardisation TN Point of departure Demo WP1: Current Practice Time Fig.. 2 Exec. RIMAP Work Process To implement and manage a system for risk based inspection and maintenance management sets requirements to a plant’s (maintenance) management system.II RIMAP Tools Damage Mechanisms NDT Efficiency Human factors PoF CoF D3. 4 RIMAP document hierarchy The main deliverables from the RIMAP RTD project will be (compare Fig. The RMAP TN project accompanies the entire development by disseminating the information and results of the RTD and DEMO part to a wider community of companies to review what has been developed and to get an overall acceptance. RIMAP Documentation Level . Implementation of RIMAP also requires an active management that focuses on the following issues: • Management of change • Operating procedures • Safe work practices • Pre-start-up reviews • Emergency response and controls • Investigation of incidents • Training • Quality assurance . • Guidelines for practical use.1) RIMAP Documentation Level .1 and I3. The project is currently completing WP4 and WP5 in addition to having started the industry specific demonstration projects.x Fig.x as Appendices to D3. 5 illustrates the work processes involved in developing a risk based maintenance and inspection plan as well as implementing and managing this plan at a plant or facility.III RIMAP Application Workbooks Power Petrochemical Steel Chemical D4. Fig. in the format of one "Workbook" for each industry sector.1 RIMAP Documentation Level .I D2. • Spread knowledge between industry sectors. to prove the applicability of the methodology.The RIMAP DEMO project consists of 4 demonstration cases. 4): • A method describing a unified approach to maintenance and inspection planning based on risk decision criteria and cost optimization.1 RIMAP Framework RIMAP Validation / Benchmarking WP5 Overview Document (D3. RIMAP defines the working processes and provides requirements to the personnel that shall execute the working processes. one for each industry sector. Summary & Introduction to RIMAP RIMAP Procedure D2. 6 illustrates how different methods of analysis are applied to each type of equipment. The steps in the process above are the same for all involved industry sectors (petrochemical. Fig. where all necessary competencies are represented and expertise are available. goals & Programme requirements Organisation Materials Execute Work orders Active management Resource needs Support Plan Tasks & Activities Perform Corrective Actions Prepare Improvement Tasks Results Costs Technical condition Evaluate Technical condition Reliability SHE level Report Failures & Status Fig. Another important issue is the regular evaluation to assess the performance of the maintenance and inspection activities based on the new data that becomes available from these activities. PoF. The RIMAP description of Risk. as well as instrument protective functions (IPF). . & Maint.Resources Management of work processes Define Establish Insp. chemical). static components. CoF The RIMAP project provides guidelines on how to perform risk based inspection and maintenance planning for all types of equipment: active components. 6 Structure of analysis The steps required to perform maintenance and inspection planning are similar for each type of equipment: Plant hierarchy: The plant hierarchy is a prerequisite for an efficient risk assessment and maintenance and inspection planning. Equipment database Screening Experience Risk Level High Risk Containment Y RBI N Low Risk Run to Failure evaluation Protective Function Y SILassessment RBM N RCM SIL: Safety Integrity Level Fig. since the plant is divided into manageable sections. It requires a team. steel. power. 5: RIMAP Work process Risk based inspection and maintenance planning is a multidisciplinary task. This may lead again lead to a sub-optimal maintenance and inspection plan. and damage mechanisms. loss of all fluid within the segmentation area. rate models. Probability of failure (PoF): A number of methods for determining the probability of failure are discussed (expert judgement. is combined with the CoF assessment to obtain a risk for the given maintenance program. or business). by means of an event tree PoF Fig. failure modes. Scenario development: RIMAP uses risk. causes etc. environment. • Instrument protective functions: For instrument protective functions the risk assessment is used to determine a requirement on availability. physical models. The PoF limit is combined with the damage rate to obtain a maximum time to inspection. the acceptable risk is combined with the consequence of failure to determine a PoF limit. The PoF assessment enters into the analysis in different ways for the static equipment. see Fig. Event Consequence tree CoF analysis e. ignition. operational disturbance or similar) the probability and consequences of which are analyzed in order to define risk related to it. RIMAP recommends the use of the expected scenario in analyses. A scenario is damage mechanisms leading to a potential event with a consequence (safety. etc. statistical.g. CoF Cause tree: PoF analysis covering e. functional problem. issue. • Active components: The PoF assessment. the combination of probability and consequence of failure.g. 7 The “Bow-tie-model” RIMAP distinguishes between two types of scenarios: • Worst case scenario: Combine a given root cause/damage mechanism with the most serious/severe consequence that the given root cause/damage mechanism may lead to. instrument protective functions and active components: • Static equipment: For trendable degradation mechanisms. This limit is then used to determine maintenance strategies that meet the requirements. Failure or main event (e. health.g. 7. e. If not. – “adverse event”. The failure modes are then used to identify failure causes. this will affect the choice of risks that will be mitigated. etc.g. The assessment of the probability and consequence of failure are combined in the bow-tie model. given a certain maintenance program. root causes.Failure mode: Assigning functions and sub-functions to the physical items at the plant simplifies the identification of failure modes. to prioritize inspection and maintenance activities.) The industry specific workbooks contain industry specific models. It is essential that the choice of approach is made before the analysis starts and that the same method is used consistently throughout the analysis. problem. • Expected scenario: Combine the root cause/damage mechanism with the expected or typical consequence that the given root cause/damage mechanism will lead to. . 8 Method for identifying mitigating activities RIMAP STEEL DEMO APPLICATION The RIMAP steel application workbook was tested on the vacuum degassing (VDG) subsystem at the BOS plant. Complying with the requirements implies that the RIMAP procedure has been followed. The consequence assessment applies to all equipment types (rotating. Canfailure failurecause causebe beidentified identifiedand and Can eliminationclearly clearlycost costeffective? effective? isiselimination YES Implement Implement Procedures • • Procedures Modification • • Modification • Operatingconditions conditions • Operating NO Establishmaintenance maintenancestrategy strategy Establish YES Maintenancestrategy strategyimplies implies Maintenance lowrisk riskfor forpersonnel personneland and aalow introductionofofnew newfailures. static. The methods are easily extended to other industry sectors. a cost-benefit assessment is proposed. Fig. operational constrains depending on the actual case. introduction Substitutionofofmaintenance maintenance Substitution strategypossible? possible? strategy NO Redesign Redesign NO YES Apply Apply Fig. health. The cost related to the mitigation cost. A sketch of the VDG unit is shown in Fig 9. The level of risk is compared to the company acceptance criteria regarding safety and environmental risk. Corus carried out this work in close . Methods have been provided for assessing • Safety – instant consequences on humans within or outside the plant’s area. the benefit is the reduced risk related to the mitigation. at the Corus Scunthorpe (UK) site. The VDG unit was chosen based on foreseen increased utilisation and that the unit represents a crosssection of the equipment types within a steel plant. Risk assessment: Risk is the combinations of the probability of failure and consequence of failure. • Environmental consequences and business consequences of failure. Consequence of failure (CoF): A set of requirements to CoF assessments have been formulated. Mitigation activities can be maintenance/inspection. environment. business) mitigating activities are proposed for the high-risk items as illustrated in the figure below. The objective of the VDG unit is to purify the liquid steel and clean out gas emissions in the molten steel. Mitigating activities and risk reduction: Based on the risk assessment (safety. For financial and cost consequences. instrument protective functions) and to all industry sectors represented in the project. redesign.For all types of equipment more frequent inspection or maintenance (than currently used or legally required) may be proposed if this is cost effective. • Financial consequence of failure. • Health consequences – long term effects on humans within or outside the plant’s area. failures. The overall aim for Corus was to test out the methodology presented in the RIMAP program and to establish a maintenance program for the VDG unit that optimise operations in a future increased demand for the VDG unit. 8 provides a decision tree for identifying mitigating activities. The RIMAP approach helps to document the knowledge of the personnel in the maintenance system. The result of the RBIM study was hence a major change in workload for a relatively small unit. Fig. results in risk reduction. The suggested risk based methodologies are a means for satisfying the requirements from the government. By adopting a risk based regime the overall cost and SHE standard are optimised as the resources are focused to the most important areas. The RIMAP steel demonstration project has shown that the RBIM methodology is easy to adapt. 9 The vacuum degasser unit (Courtesy of the Corus group) The analysis shows that the annual cost of preventive maintenance and inspection could be reduced by 20% per year.) and encourages thought processes in a structured manner” “Offers new tools in decision making . Assigning risk to each plant item and assigning mitigating actions based on the risk assessment. The need for this is increasing as the demands for traceability and history increases. service area asset risk management of DNV Consulting. The RIMAP steel demonstration project has shown that an RBIM (risk based inspection and maintenance) analysis and a risk based approach to maintenance and inspection planning may improve Corus’ performance in a number of areas. This reduces dependability of “experienced” personnel and facilitates sharing of knowledge between sections and sites.cooperation with Det Norske Veritas. In addition there is potential for additional savings after implementation. The potential reduction only accounts for the direct savings related to preventive maintenance labour costs. documenting decisions and processes and follow up of history.but with experienced input captured” . and the work was characterised as an eye-opening experience. Some comments made by Corus during the analysis is presented below: “RIMAP challenges new ideas (what if? etc. The new maintenance program will also result in increase uptime in the VDG unit (due to a reduction of PM activities that require stops) as well as a reduction in use of spare parts. During the analysis the team successively recognised the risk based mindset and at the end they fully adopted the concept. The work generated new ideas and revealed areas that needed focus. The RIMAP approach provides a documented basis for decisions concerning the inspection and maintenance regime. The participants expressed excitement and satisfaction. This can be achieved without compromising regularity and at the same time increasing the safety level of the unit. by means of continuous evaluation of effectiveness of maintenance and inspection activities. The current project RIMAP. Research Project RIMAP Risk Based Inspection and Maintenance Procedures for European Industry". The application of the RIMAP approach in the steel industry was very successful. The following companies participate in the RIMAP project: Det Norske Veritas AS (DNV) ExxonMobil Chemical Ltd. documented thought process” “An idea was to combine some (if suitable) electrical and mechanical inspections on the same kit to the same times to avoid any extra plant downtime” “In some cases it was decided that it would be beneficial to split some plant areas down further on the CMMS so we can see where the money is being spent” CONCLUSION European practices for risk based decision making are under development to create a guideline and applicable tools for practical use. (see References). The cost of inspection and maintenance can be reduced and process proved successful in changing the mindset of the participants and in implementing a risk based approach towards inspection and maintenance. involving more than 40 companies promise to deliver a desired level of a consolidated European risk based practice.“The project gives management confidence that this work force has gone through a structured. . NOMENCLATURE CoF D EU ISI NDT PED PoF RIMAP WP Consequence of failure Deliverable European Union In-service inspection Non-destructive testing European Pressure Equipment Directive 97/23 Probability of failure Risk Based Inspection and MAintenance Procedures for European industry Work package ACKNOWLEDGEMENT Risk Based Inspection and Maintenance Procedures for European Industry (RIMAP) is a project partly financed by the European Commission for the "Growth Programme. Contract Number G1RD-CT-2001-03008. Detailed information can be gathered on the project’s websites. (Exxon) Bureau Veritas (BV) Energie Baden-Württemberg AG (EnBW) Staatliche Materialprüfungsanstalt Siemens AG (Siemens) (MPA) Joint Research Centre of the European VTT Industrial Systems (VTT) Commission (JRC) TÜV Industrie Service. TÜV SÜD Group Electricity Supply Board (ESB) TNO Industrial Technology (TNO) Corus Ltd. The authors would like to acknowledge the financial support by the European Commission. dnv.com .de/rimap Sture Angelsen.mpa-lifetech. REFERENCES RIMAP RTD or RIMAP Demo project: RIMAP TN: http://research.com/rimap http://www. (DOW) Solvay S. (Norsk Hydro) Mitsui Babcock Energy Ltd.V. Norway sture.A.com Alasdair Pollock Corus Northern Engineering Services Steel House Redcar Teeside TS10 5QW [email protected] Agri Sluiskil [email protected]. Mikael Johansson. (MBEL) The Dow Chemical Company N. Gjermund Våge Det Norske Veritas N-1322 Høvik.