Reduce Coupling Maintenance Costs through Online Monitoring - MTA-MA-011

Administrative Items
Date	12/15/2020
Functional Area Where Benefits Will Be Realized	Maintenance Engineering
Reference Implementation Guidance	Continuous On-Line Monitoring: Couplings, Gear Type – Grease Lubricated (EPRI 3002012775) Continuous On-Line Monitoring: Couplings, Disc or Diaphragm Type (EPRI 3002012776) Continuous On-Line Monitoring: Couplings, Elastomeric Type – Jaw or Spider Insert (EPRI 3002012777) EPRI Preventive Maintenance Basis Database (PMBD) (EPRI 3002005428)
Industry SME	EPRI – Mike Taylor Contact: NuclearPlantMod@epri.com
Previous Implementation	Please contact EPRI for implementation examples and contacts.
Implementation Enablers	MTA-MA-003 – Implement a Wireless Network Infrastructure Using a Distributed Antenna System (DAS) MTA-MA-004 – Implement a Wireless Network Infrastructure Using WiFi
SWEEP Score	Cost – Level 3 – Implementation costs should be less than $1 million. Savings – Level 1 – Savings are less than $1 million per year. Payback – Level 2 – Based on available cost and savings information, payback period for implementation would be greater than one year but less than five years. Licensing Readiness – Level 3 – Elements of this approach have already been implemented at nuclear power plants. Technology readiness – Level 3 – The technology is ready for wide operational deployment. Advanced OLM on couplings has already been implemented at fossil generating facilities. Implementation proficiency – Level 2 – Implementation proficiency is dependent on site‑specific experience related to wireless data infrastructure, wireless data transmission for maintenance and monitoring, cyber‑security protocols, etc.
Applicability	All reactor types All geographic regions
Keywords	On-line monitoring; couplings; equipment reliability; condition-based maintenance; quick guides; vibration
Business Case Analysis Cross-Reference	N/A

Description

Data acquisition and processing tools have reached the point where Continuous Online Monitoring (COLM) of equipment is possible and cost‑effective. COLM can be used to transition from time‑based preventative maintenance (PM) to condition‑based maintenance (CBM), which reduces maintenance costs by eliminating or reducing premature maintenance activities. COLM also provides valuable insights into equipment health that may help to detect incipient failures before major equipment damage. This MTA specifically applies to the vibration monitoring of couplings.

A coupling connects two shafts together at their ends to transfer motion. To function properly, couplings require routine inspection and maintenance (e.g., vibration analyses). Historically, these inspections and maintenance have been performed through time‑based periodic maintenance. Technology advances in sensors, wireless communications, and data analysis now enable continuous monitoring and trending of various component parameters. Couplings have been historically linked to equipment failures from shaft misalignment or improper lubrication; monitoring couplings would provide benefits in avoided costs. Additionally, properly implementing coupling COLM could allow for the elimination of existing inspection activities or a transition to CBM.

Benefits

Benefits Estimate

Level 1 – Savings are less than $1 million per year. Potential savings are achieved through eliminated maintenance tasks or extended maintenance intervals.

Benefits Description

• Potential labor savings for eliminated or extended PM and inspection tasks by transitioning to CBM. As an example, vibration analyses of couplings could be replaced with COLM.
• Early detection of equipment degradation, resulting in reduced equipment forced outages and corrective maintenance (CM) costs.
• Improved visibility to asset or system condition through more frequent data collection.
• Reduced risk of equipment unreliability caused by maintenance, because COLM replaces PM items or extends the maintenance interval.

Costs and Schedule

Cost

Level 3 – Implementation costs should be less than $1 million. These costs include the sensors, installation, and software. This cost can be shared site or fleet‑wide if other components implement OLM.

Schedule

Six months to two years, which includes planning and implementing new sensors.

Scope Context

Per unit. All rotating equipment have some sort of coupling that can be monitored. Results for multi‑unit sites or across a fleet should be scaled, accounting for any potential efficiencies in larger deployments.

Risks

IT risks associated with integrating with existing plant network, data storage, and analysis software. Addressing IT concerns at the requirements phase of the project (for example, how the sensor data will be gathered and used) will mitigate this risk.

Sensors can vary in implementation difficulty and cost.