Hyper-Integrated Causal Analysis (HCA) in Action
Case Study: Repetitive Motor Failures at a
Chemical Weapons Destruction Plant
7 Motor Failures
In an 11-month period
Figure 1 - 4160 volt Motor Platform
Multiple Failure Modes
Coupling, Shaft, Bearings
An independent BlueDragon HCA was commissioned by the prime contractor at a Department of Defense installation. During a period of 11 months, the three installed Compressed Air System (CAS) motors had experienced 7 failures (Figure 1). The three trains of CAS motors provide vital breathing air for site operations.
The HCA team consisted of Rob De La Espriella (the BlueDragon Team Lead), the motor System Engineer, and two volunteers in support roles.
Fault Tree Analysis
Electrical and mechanical Failure Modes
BlueDragon RCA Team
Rob plus three - 1 SME
The Fault Tree helped identify the failure modes for the 7 motor failures
Figure 2 - Fault Tree Analysis
The BlueDragon Hyper-Integrated Causal Analysis (HCA) is a 3-phased approach that included the following activities, performed in a seamless and efficient manner:
Phase 1 - Analysis of available data and evidence to develop focused, evidence-based Lines of Inquiry.
A detailed timeline was developed for each of the three trains of CAS motors. Additional details were added to the timeline from the results of the causal analysis sessions.
The BlueDragon team facilitated the development of a Fault Tree (Figure 2) using the two motor vendors and other subject matter experts (SMEs). The mechanical and electrical failure modes for this motor were identified. The Fault Tree allowed the team to establish a comprehensive troubleshooting plan to rule out as many of the failure modes as possible. A major component of the troubleshooting plan involved the installation and testing of a CAS motor. After extensive troubleshooting, the RCA Team was able to identify the probable causes of the seven motor failures.
An analysis of the defenses in place to prevent these kinds of events was conducted. The analysis included a total of 92 administrative requirements that were evaluated for effectiveness, as well as physical barriers and equipment interfaces.
Approximately 80 focused, evidence-based Lines of Inquiry were developed as the starting point for the causal analysis (Figure 3). To develop the Lines of Inquiry, HCA used available information from the chart to conduct a seamless and integrated analyses that included: Comparative Timeline Analysis,Task Analysis, Change Analysis and Barrier Analysis.
Phase 2 - Facilitated Causal Analysis sessions to identify the root causes and significant contributing factors.
There were a dozen facilitated causal analysis sessions conducted on-site at the client's facilities, which included Maintenance personnel, Subcontract Technical Representatives (STRs), Engineering personnel, Millwrights, Work Control Planners and Schedulers, Quality Control personnel, three different vendors, and managers from across the project.
The BlueDragon team guided the organization's SMEs through the causal analysis process, using their expertise to answer the Lines of Inquiry and identify the deepest-seated (root) causes and significant contributing factors.
The BlueDragon chart captured the results of the causal analysis sessions live (in real-time), with the participants observing how their answers were documented (total transparency). There are very few notes taken during this HCA process as the results are captured on the chart.
HCA calls for the results of the causal analysis to be validated by every group that participates. By the end of the analysis, the results had been validated up through the senior managers that participated in the process.
Phase 3 - The proposed corrective action plans and extent of the cause reviews to close performance gaps and prevent recurrence of the deepest-seated causes.
Corrective action plans are usually the responsibility of a separate group and requires additional input that includes the organizations budget and resources.
The HCA team provided informal recommendations to the organization for addressing the identified root causes and contributing factors.
Identify the Root Causes
Using the BlueDragon Chart
Integrates Multiple Tools Into One Chart
Figure 3 - BlueDragon Chart
The BlueDragon HCA was completed in 10-days. This level of efficiency can only be achieved by integrating many of the methods and techniques that are customarily done separately.
The HCA investigation identified four root causes, five significant contributing factors and a number of opportunities for improvement. Note that the results are derived by the SMEs participating in the causal analysis process, and not by the HCA team in a vacuum.
The exit briefing with the client's senior managers took place at noon on the 10th day. Briefings are conducted from the BlueDragon chart, which is a storyboard; no documents are provided to managers at the exit briefing.
Hyper-Integrated Causal Analysis (HCA) in Action
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