44 JUL-SEPT 2010 Visit our websites at www.safan.com / www.pm-pipeliner.safan.com

Integrity Management SoftwareSolution - Managing your dailyactivitiesBy Sebastian Ruik Beyhaut

TechnologyTechnology

1. AbstractMany owners of vertical above ground storage tanks

have their own dedicated Asset Integrity ManagementSystem in place. However, due to increasing local andinternational regulations, higher operational costs, andlack of resources, implementing supporting tools for a fullycompliant system is a challenging step for mostorganizations.

One of the primary objectives of an Asset IntegrityManagement System (AIMS) is to maintain assets operationalcondition in the most reliable, safe, and cost-effectivemanner. In order to overcome these challenges, ROSENsexperts have developed a supporting tool which ensuresqualitative and quantitative data management, which assistthe tank owner in his decision making processes throughoutthe system and lead him towards the direction of preventivemaintenance regime.

This paper presents a tool for supporting a maintenancemanagement process illustrated by a case study. Thesupporting tool is intended for professionals at every level,as part of a Total Integrity Management System. The resultsof the study show how the different process aspects arehandled and supported by ROSEN Asset IntegrityManagement Software (ROAIMS) Tank Suite, helping tooptimize inspection and repair expenditures based ondetailed Inspection assessments.

2. BackgroundWith advances in inspection approaches, and increasing

understanding of the type and rate of degradation, inspectionintervals became more reliant on the actual state of theequipment, instead of considering a predefined interval by

local authorities. Codes such as API 510 and 570 evolvedto an inspection philosophy defining inspection intervalsbased on equipment half-life, furthermore worldwidestatutory authorities have opened thier minds by increasingthe allowance of flexible inspection intervals.

API RP 580 for Risk-based Inspection provides a way andrecommendations for defining inspection interval byfocusing on optimizing risk reduction. May we draw yourattention in the fact that ROSENs Tank RBI methodologywas compiled with the objective that it would comply withthe API requirements for applying RBI. Although the riskmanagement principle and concepts that RBI is built on areuniversally applicable, RP 580 is specifically targeted at theapplication of RBI in the hydrocarbon and chemical processindustry.

RBI, as a risk-based approach, focuses specifically on theequipment and associated deterioration mechanismsrepresenting the most risk to the asset. In focusing on risksand their mitigation, RBI provides a better linkage betweenthe mechanisms that lead to equipment failure and the

Figure 1: API RP 580 defines the following Process for RBI

JUL-SEPT 2010 45

inspection approaches that will effectively reduce theassociated risks. The main targets are to avoid catastrophicfailures, unplanned shutdowns, minimize and structure theIn-service maintenance & inspections (NDT), last but notleast optimized planned shutdown.

The final deliverable of ROSENs Tank RBI methodologyis an inspection plan for the tank and its sub-components.The inspection plan details the activities related to thecurrent operation from a safety/health/environmentperspective and/or from an economic standpoint. For risksconsidered unacceptable, the plan contains the mitigationactions that are recommended to reduce the unmitigatedrisk to an acceptable level. The plan describes the type,scope and timing of inspection/examination recommended.Ranking of the tank components by the unmitigated risklevel allows users to assign priorities to the variousinspection/examination tasks. This ranking is graphicallydone in a matrix where the components are plotted usingprobability and consequence outcomes.

3. RBI Benefits and LimitationsThis RBI plans also identify equipment which does not

require inspection or some other form of mitigation. As aknock-on effect, this can end up in an important decreaseon the amount of inspection data that is collected, thusinspection and maintenance activities can be focused andmore cost effective. Therefore, in some cases, RBI plansmay not only result in absolute risk reductions and processsafety improvements but also in cost reductions.

RBI is based on sound, proven risk assessment andmanagement principles which play an important roleduring this exercise, and hence rubbish in, is rubbish out.RBI will not compensate inaccurate or missing information,inadequate designs equipment installation, operatingoutside the acceptable design envelope, not effectivelyexecuting the plans in a timely manner, lack of qualifiedpersonnel or teamwork, and lack of sound engineering oroperational judgment. Moreover, risk mitigation is notobtained if inspection data that are gathered are not properlyanalyzed and acted upon where needed. The quality of theinspection data and the analysis or interpretation willgreatly affect the level of risk mitigation. Therefore, properinspection methods and data analysis tools are criticalissues which should be considered.

4. ECOPETROL S.A.ECOPETROL S.A. is one of the largest petroleum

companies in Latin America, and among other assetsoperates pipeline network of approximately 8,500 km andmore than 250 above storage tanks in Colombia only.

During 2006-2008 ECOPETROL S.A. successfully carriedout an implementation of Asset Integrity ManagementSoftware provided by ROSEN (ROAIMS) and execution ofassociated services which involved data integration andrisk assessment. ROSEN provided ECOPETROL S.A. withthe knowledge and software tools for Quality Assurance/Quality Control of the individual processes within theirsystem.

Before the project ECOPETROL S.A. had digital files withinformation of tank inspection and integrity spread all overthe country. Mechanical data, tank inspections and otherimportant data were available in printed version and excelsheets. Therefore, the need for a centralized and morerobust system was recognized.

5. Project Framework for RBI implementationBased on API 580, a detailed approach was developed to

tackle a challenging implementation step into ECOPETROLS.A. system.

The core of a RBI assessment is being aware of the factthat this exercise is a team-based process. During the initialmeetings between ROSEN and ECOPETROL S.A. Engineersrelevant decision were made, e.g. define relevant RBItargets, describe the way of doing it, teams involvement,responsibilities, definition of roles, codes and standards tobe used, the length of the assessment and future uses of theresults.

Identification of the appropriate deteriorationmechanisms, susceptibilities and failure modes for all tankcomponents included in the RBI study were defined whichhad an effect on the quality and the effectiveness of the RBIevaluation. Corrosion specialists were consulted to definethe equipment deterioration mechanisms, susceptibilityand potential failure modes. Data used and assumptions

Figure 2: Project implementation

46 JUL-SEPT 2010 Visit our websites at www.safan.com / www.pm-pipeliner.safan.com

made were validated and documented. The deteriorationmechanisms, rates and susceptibilities were the primaryinputs into the probability of failure evaluation. The failuremode is a key input in determining the consequence offailure except when a worst case consequence analysis,assuming total release of component inventory, is used.This fact brings us to the conclusion that within ROSENtank RBI, only credible scenarios were analyzed.

RBI is a dynamic tool that can provide current andprojected future risk evaluations. As time goes by, changesare inevitable and the results from the RBI assessment areupdated by the user of the system. ECOPETROL S.A. isconscious of the importance of maintaining and updatingthe RBI methodology assuring that the most recentinspection, process, and maintenance information isincluded. The results of inspections, changes in processconditions and implementation of maintenance practiceshave significant effects on risk and can trigger the need toperform a reassessment.

6. Acceptable and unacceptable riskFor Tanks with low Risk the inspection intervals derived

from the RBI procedure may be longer than the maximumpermissible inspection interval prescribed by locallegislation which is governing. In order to focus on the rightpriorities, a distinction should be made between itemsqualified as High compared with those indicated asLow or Medium.

If the risk is unacceptable, irrespective of its rating, a fulltank integrity assessment (TIA) needs to be carried out bythe RBI team preferably under guidance of a qualified tankIntegrity Assessor. In general this assessment is a teameffort. The TIA should be capable of making a soundassessment of the integrity of storage tank and foundationin order to offer guidance on the need for repair, itsurgency, and the methods of affecting such repair.

7. Roles, Responsibilities, Training andQualifications

Considering that ECOPETROL S.A. Integrity engineersdid not have the background to conduct the entire RBIassessment in an effective manner, a tailored training wasorganized at early stages of the project. All team members(e.g. Tank inspector(s), Tank maintenance staff, Operationsstaff, Material/corrosion engineer(s), reliability engineer,etc) received basic training on RBI methodology and on theprogram(s), being used primarily geared to an understandingand effective application of RBI. Moreover, the traininghelp them with understanding the technical integrity issuesof tanks in general and its consequence if something goes

wrong. It certainly brought them awareness about tankmaintenance in gen