As shown above, instead of running equipment to failure or performing preventive maintenance based on a calendar, equipment run-time or usage-based factor, a more desirable approach can be applied to measure material condition in order to determine the right time to perform maintenance. As CBM+ technologies evolve, the Navy will be able to collect data that will aid in predicting when equipment will fail thereby reducing corrective maintenance costs.
RCM Supports CBM+
Reliability centered maintenance (RCM) principles are the base that CBM+ is built upon. Using RCM, the Navy can ensure sensors are properly installed and placed where they can detect the failure modes that are trying to be prevented. When sensors are installed using RCM analysis and tied to preventive maintenance tasks in the Planned Maintenance System (PMS), maintenance can be triggered based on specific events such as reaching a particular equipment run time or exceeding a measured limit.
Unfortunately, there are numerous sensors on ships today that do not align to any PMS tasks and do not provide useful performance information because they are capturing data from areas unrelated to significant functional failures. Functional failures occur when the system or equipment fails to operate within the designated parameters. To prevent this mismatch from happening with new acquisitions, NAVSEA is working with program executive offices and field activities to ensure the proper placement of sensors using RCM analysis. Additionally, NAVSEA is taking the necessary steps to ensure that CBM+ is included in all future contracts to hold equipment providers accountable for proper sensor placement, installation, and compatibility with existing and follow-on data systems.
The use of CBM+ technologies is not only gaining attention in the Navy because of its proven success in the commercial world and throughout the Department of Defense, but because it can reduce the administrative burden on ship’s force. Additionally, using CBM+ technology improves the operational readiness and availability of equipment and will reduce future maintenance requirements.
CBM+ Test Pilots
The Navy is ambitiously working towards having sensors and CBM+ enabling technologies aid in scheduling preventive maintenance tasks when needed. To this end, a number of CBM+ technology pilots have been initiated with the hope of significantly helping the future fleet, Sailor quality of service and equipment availability. Examples of the benefits CBM+ implementation offers are explained in the pilots detailed below.
When the littoral combat ship (LCS) class was being designed, engineers, architects and designers knew the unique concept of operations, optimal manning and off-ship maintenance plan presented a special opportunity to apply CBM+ to this fleet asset. Therefore, they worked early in the ship’s lifecycle to apply sensors to key equipment. LCS 1, 2 and 3 have leveraged the highly “sensorized” equipment sets delivered to the fleet as part of a CBM+ pilot testing a technology called the Machinery Reliability Management System (MRMS).
The pilot saw a number of successes including the prediction of impending failures for equipment being monitored. These potential failures were headed off by thorough analysis of data received from over 6,800 sensors.
Overall, the LCS CBM+ pilot was instrumental in the sustainment of both LCS 1 and 3 during their maiden overseas deployments and garnered positive feedback from their crews and shore-based support teams. The pilot achieved several objectives: predicting remaining useful life of equipment, diagnosing failures, assisting in the scheduling of maintenance tasks for upcoming availabilities, reducing crew workload, and helping operators and maintainers make smart decisions that reduced risks and impacts to the ships’ operations and schedules. Lessons learned from this pilot will help inform and shape the future of LCS CBM+.
Another exciting pilot is underway. This pilot attempts to automatically schedule needed maintenance by linking data received from sensors and analyzed through a remote monitoring system directly to the Navy’s existing PMS scheduling tool (SKED) onboard ships. During a recent test conducted in a lab environment, the pilot successfully demonstrated the communication and transfer of engine data to SKED that resulted in a recommendation to the work center to schedule seven associated MRCs. Once the pilot is successfully tested on board ships and business rules are developed and tested to ensure correct scheduling, this direct maintenance scheduling capability will reduce the scheduling burden placed on Sailors while ensuring maintenance is performed only when the condition shows it is needed.
NAVSEA is doing its part to advance maintenance scheduling to the next level and to improve the Sailor’s ability to assess equipment and systems by implementing CBM+. In time, the use of properly placed sensors and advanced CBM+ technologies will allow the automatic scheduling of the correct maintenance at the right time, so less time will be spent reviewing, planning and performing maintenance. As CBM+ technologies are implemented in the fleet, the time spent manually entering data, conducting tag outs and disassembling equipment will likely decrease as well.
And hopefully, those painful trips down to shaft alley will decline too.