WF21: Classify Maintenance Action (Back-Fit RCM)

Pre-requisites

• RAM Module: Reliability, Availability and Maintainability (RAM) Module enables access to Back-Fit Reliability-Centered Maintenance (B-RCM) Analysis.
• FBD Model: model items defined with reliability data and failure diagrams.

Detailed Descriptions (numbered steps)

1. Access Back-fit RCM Analysis via the right-click context menu opened on the target model item, or alternatively under 'Analyses' in the main menu bar whilst target item is selected.
2. Define time span that the analysis shall be performed over, supported with a narrative.
3. Select tick boxes adjacent to existing maintenance action(s) applicable to target model item.
4. Select failure mode, from the drop-down menu, and continue to the next tab 'Failure Assessment', to begin the analysis.
5. Determine if there is an existing maintenance action to review, before conducting failure mode assessment.
6. Determine if failure mode is significant to warrant further analysis. If not significant, recommendation shall be NO CHANGE.
7. Determine if a maintenance action could address the failure mode, resulting in recommendation of ADD NEW TASK. However, if not, recommendation shall be RE-DESIGN.
8. Select existing maintenance action from drop-down menu.
9. Determine if failure mode is significant to warrant further analysis. If not significant, recommendation shall be DELETE TASK.
10. Select radio button adjacent to classification applicable to maintenance action.
11. Maintenance action classified, enabling Back-fit RCM Analysis to continue.

Fields referenced in the diagram

• Define Back-fit RCM Analysis Time Span: Time Span, Narrative
• Select Existing Maintenance Action(s): Import Action, Copy Action, New Action
• Classify Maintenance Action options: Condition-directed, Time-directed, Failure Finding, Servicing, Lubrication

Decision points

• Existing Action? — No → Failure Mode Significant? decision (leads to NO CHANGE or ADD NEW TASK/RE-DESIGN); Yes → Select Maintenance Action.
• Failure Mode Significant? (no existing action branch) — No → Recommendation: NO CHANGE; Yes → Action Applicable? decision.
• Action Applicable? — No → Recommendation: RE-DESIGN; Yes → Recommendation: ADD NEW TASK.
• Failure Mode Significant? (existing action branch) — No → Recommendation: DELETE TASK; Yes → Classify Maintenance Action.

Screenshot walkthrough (captions/labels extracted)

Step 1: Access Back-fit RCM Analysis

• Project Explorer tree: Vehicle System [4/29] > Functions, Coupling, Driveline [11], Power Generation [3/14] > Functions, Control Measures, Control Unit, Diesel Engine [8], Fuel Tank (highlighted); Vehicle. Context menu on Fuel Tank: New (System Model, Failure Diagram, Functions), RBD Model, Back-Fit RCM (highlighted), Maintenance Actions, Markov Analysis, Cut/Copy/Paste, Delete, End Effect Item, Response Paths, Override Failure Diagram, Failure Injection, Response Simulation, Load from Library, Save to Library, Advanced Properties.
• 'Analyses' menu equivalent: Fault Tree, Response Paths, Connection Matrix, Common Mode Analysis, Critical Item Analysis, Criticality & Reliability Editor, Technical Budget Analysis, Failure Rate Prediction, Markov Analysis, RBD Analysis, Reliability Allocation Editor, Back-Fit RCM (highlighted), Model-based RCM, Maintenance Cost Estimates.

Step 2: Define Back-fit RCM Analysis Time Span

• "Back-Fit RCM - Fuel Tank": left nav NAVSEA Road Map, Maintenance Association, Back-Fit Summary. "Back-Fit RCM Time Span": "Provide the time span that the Back-Fit RCM analysis will be performed over." Time span "1.00" "years". Narrative: "Back-Fit RCM analysis covers the analysis of the Fuel Tank for the operational period from 2022 to 2023."

Step 3: Select Existing Maintenance Action(s)

• "Existing Maintenance Actions": "Select the Maintenance Action(s) that are currently performed on the Maintainable Item. These Maintenance Actions will be available to select as the 'Existing' Maintenance Action for a Failure Path. Without specifying any Existing Maintenance Actions, the options available for the Back-Fit RCM workflow will be significantly reduced." Buttons: Select All, Deselect All, Import..., Copy..., New... Table (Name/Used/Interval (hrs)/Cost(USD)/Duration (hrs)/Downtime (hrs)): Fuel Tank > "001 - Breakdown Maintenance" (Used "No", Interval 2593.87, Cost $2,600.00, Duration 6.00, Downtime 6.00).
• "Import Maintenance Action" dialog: "Select a Maintenance Action to import a copy into Fuel Tank." Tree: Vehicle System > Power Generation > Control Unit > "001 - Scheduled Repair" (selected). Details: Action ID "001", Action Name "Scheduled Repair", Description "Scheduled Repair based on MCE Analysis 1.", Maintenance Type "Scheduled Repair", Maintenance interval (hrs) "800", Does Maintenance require shutdown? "No", Inspection interval (hrs) "N/A", Does inspection require shutdown? "N/A", Location of Maintenance "Field". Buttons OK, Cancel.
• "Create a New Maintenance Action" dialog: Action ID "000", Action Name "New Maintenance Action", Description, Maintenance Type "Breakdown - Repair" dropdown, checkbox Continuous Monitoring, Maintenance interval "0.000 hours", Inspection interval "N/A hours", Location of Maintenance "Field", CCMR checkbox. Tabs: Maintenance (Tasks and Personnel / Equipment and Consumab...), Inspection (Tasks and Personnel / Equipment and Consumab...), Linked Failures ("12 of 12 Failures linked"), Summary ("0 hrs / $0.00"). Empty task table (ID/Task Name/Downtime/Duration (hrs)/Rate (USD/person/hr)/# Personnel/Total (USD)). Buttons OK, Cancel.

Step 4: Select Failure Path

• "Back-Fit RCM - Fuel Tank": top bar Previous Failure / failure dropdown "Corroding of Lining due to Cavitation corrosion" (expanded list: Corroding of Lining due to Cavitation corrosion, Corroding of Lining due to Corrosive attack, Interfering of Lining due to Buildup of debris, Perforating of Inlet due to Corrosive attack, Perforating of Lining due to Corrosive attack) / Next Failure / Recommendation "Continue Analysis". Tabs: 1. Identify Failure Mode (selected) through 8. Proposed Maintenance. "Identified Failures Modes": explanation that failure paths are automatically extracted from the Failure Diagram of the Maintainable Item. Table (Failure Paths/Recommendation), all "Analyze": Blocking of Lining due to Buildup of debris, Interfering of Lining due to Buildup of debris, Seizing of Lining due to Buildup of debris, Corroding of Lining due to Cavitation corrosion, Pitting of Lining due to Cavitation corrosion, Corroding of Lining due to Corrosive attack, Perforating of Inlet due to Corrosive attack, Pitting of Inlet due to Corrosive attack, Corroding of Lining due to Corrosive attack, Perforating of Lining due to Corrosive attack, Pitting of Lining due to Corrosive attack. "Existing Maintenance Actions": table with "001 - Breakdown Maintenance" (Used No, Interval 2,593.87, Cost $2,600.00, Duration 6, Downtime 6), Time span (hrs) "1,000", Maintainable Item MTTF (hrs) "2,593.87".

Step 5: Existing Action?

• "2. Failure Assessment" tab: "Identify Failure Mode" — "Is there an existing Maintenance Action?" radio Yes/No, guidance text for each. Existing Maintenance Action dropdown "000 - No Maintenance Action", buttons New..., Copy... "Does the Failure Mode actually occur in the service life or a significant rate of age degradation exist?" Yes/No with guidance and Comment field. "Is it possible to create a Maintenance Action to address the failure path?" Yes/No with guidance and Comment field. "Existing Maintenance Action" panel (right): Maintenance Action "000 - No Maintenance Action", Description "This Maintenance Action indicates that no action is taken. This Maintenance Action is treated intrinsically as a Breakdown action, although nothing is actually done in the event of failure." Location of Maintenance "Field", CCMR checkbox, Maintenance Type "Breakdown - Repair", Maintenance interval 0.000 hours, Inspection interval N/A hours. Tabs Maintenance (Tasks and Personnel/Equipment and Consumables) / Inspection (disabled Tasks and Personnel/Equipment and Consumables); empty task table.

Step 6: Failure Mode Significant?

• Same tab with "Is there an existing Maintenance Action?" = No selected. Recommendation banner still "Continue Analysis".

Step 7: Action Applicable?

• Same tab scrolled to show "Does the Failure Mode actually occur..." = Yes selected; "Is it possible to create a Maintenance Action to address the failure path?" = Yes selected. "Recommended Action" panel: Recommendation "Continue Analysis", note "Further analysis is required to determine the recommended change (if any) to the Maintenance." Link "Go to step 8: Proposed Maintenance."

Step 8: Select Maintenance Action

• "Is there an existing Maintenance Action?" = Yes selected. Existing Maintenance Action dropdown expanded: "000 - No Maintenance Action" (Breakdown - Repair) and "001 - Breakdown Maintenance" (Breakdown - Repair, highlighted/selected). "Existing Maintenance Action" panel updates: Maintenance Action "000 - No Maintenance Action" shown with same description; Maintenance interval, Inspection interval fields; empty task table.

Step 9: Failure Mode Significant?

• Same tab with Existing Maintenance Action now "001 - Breakdown Maintenance", "Does the Failure Mode actually occur..." = Yes selected. "Existing Maintenance Action" panel: Maintenance Action "001 - Breakdown Maintenance", Description "Breakdown Repair based on MCE Analysis 1.", Location of Maintenance "Field", Maintenance Type "Breakdown - Repair", Maintenance interval "2593.870 hours", Inspection interval N/A. Task table populated: 001 Detection/Diagnosis (Downtime unchecked, Duration 0.5, Rate $100.00, 1 Personnel, Total $50.00), 002 Removal (checked, 1, $100.00, 1, $100.00), 003 Repair (checked, 3, $100.00, 1, $300.00), 004 Reinstallation (checked, 1, $100.00, 1, $100.00), 005 Testing / Administration (checked, 0.5, $100.00, 1, $50.00).

Step 10: Classify Maintenance Action

• "3. Classification" tab: explanatory text on maintenance task types. "Maintenance Type Task" table (Name/Action/Circumstance/Typical Tasks/Evident), unselected radio buttons: CONDITION-DIRECTED (CD) — "'Renew Life' (Restore or replace) Based on measured condition compared to standard." / "Equipment characteristics corresponding to failure mode." / "Diagnostic Test, Material Condition Inspection" / "Yes/No"; TIME-DIRECTED (TD) — "'Renew Life' (Restore or replace) Regardless of condition." / "Imminent wear out." / "Discard and replace with new item" / "Yes/No"; FAILURE FINDING (FF) — "Determine whether failure has occurred." / "Failure of off-line or 'hidden' function (e.g. safety/protective devices)." / "Inspection, Functional Tests" / "No"; SERVICING (S) — "Add/replenish consumable (e.g. Windshield washer fluid)." / "Reduced level of operating consumable." / "Top off consumables (e.g. fluids)" / "N/A"; LUBRICATION (L) — "Oil, grease or otherwise Lubricate." / "Accelerated wear." / "Lubricate" / "N/A". Link "Go to Step 4: Applicability."

Step 11: Maintenance Action Classified

• Same table with "CONDITION-DIRECTED (CD)" radio selected. Tabs at top now show checkmarks on 2. Failure Assessment, 3. Classification (green checks) indicating completion.

Related workflows

• WF22 – Assess Maintenance Action (Back-Fit RCM)