E-Journal of Advanced Maintenance Vol. 11 No. 1 (2019) 34-39
Japan Society of Maintenology

TEPCO’s Work Management Initiatives
Hidenori SATO1,*, Satoshi SUZUKI1, Tsuyoshi UTAGAWA2, Masato ITO1 and Hideo
SAKURAI1
1Head Office, Tokyo Electric Power Company Holdings, 1-1-3 Uchisaiwai-cho, Chiyoda-ku, Tokyo
100-8560, Japan
2
Kashiwazaki Kariwa NPS, Tokyo Electric Power Company Holdings, 16-46 Aoyama-cho,Kashiwazaki, Niigata 945-0016, JapanABSTRACT
In order to pursue safety and efficiently manage resources, we are improving our maintenance business process
by using information technology (IT) and introducing a work management process (WM process). These efforts
have resulted in improvements in managing the duration of safety-equipment unavailability and in addressing
non-conformance backlogs.
KEYWORDS

ARTICLE INFORMATION

Information technology, Work management process, Performance indicator,
Corrective action program

Article history:
Received 21 November 2018
Accepted 9 May 20191.

Introduction

Tokyo Electric Power Company Holdings, Inc. (TEPCO) has been reforming its maintenancebusiness process by using improved IT and by introducing WM process referring to the Nuclear
Energy Institute (NEI) Standard Nuclear Performance Model (SNPM) [1] and the Institute of Nuclear
Power Operations’ Action Program (INPO’s AP) guidelines such as AP-928 [2] that describe bestpractices in the United States Nuclear Industry.
In April, 2017, the WM process was applied to maintenance work at Kashiwazaki Kariwa
Nuclear Power Plant (KK) Units 1～5, which are in long-term shutdown.The purpose of introducing
WM process by referring to the SNPM and INPO’s AP guidelines is as follows:
・To pursue safety by developing and adhering to plans that minimize nuclear safety risk andequipment protection risk of maintenance activities.
・To efficiently manage human and material resources, and enhance productivity.

2.

TEPCO’s Work Management

2.1. Reform of TEPCO's maintenance business process
We have changed our maintenance business process based on WM process that refers the SNPM
and INPO’s AP guidelines. For each core process of the SNPM, such as work management, operateplant, equipment reliability and configuration management, TEPCO has conducted gap analysis bycomparing its existing maintenance business processes with the INPO’s AP guidelines together with asupporting process called Corrective Action Program (CAP). Based on the results gained from thisanalysis, TEPCO has introduced a new business process which the company is continuouslyimproving.
This paper explains about the changes we made to the WM process, one of the core processes
mentioned above. Key points of the updated WM process are described below.
1. 7 phases and Milestone
2. Function Equipment Group(FEG)

ISSN-1883-9894/10 © 2010 – JSM and the authors. All rights reserved.

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TEPCO’s Work Management Initiatives

3. Work Window(WW)4. Performance Indicator(PI)Fig. 1. Gap/difference Analysis with SNPM and INPO’s AP-928

2.2. Milestones and Activities in WM Process
WM process is divided into 7 phases and Milestones set up. Milestones are set for each month up
to the Execution phase. Figure 2 shows the contents of implementation at each phase of WM.
Equipment maintenance activities are managed by Work Order (WO) utilizing IT system. WO isissued for preventive maintenance, design change request, non-conformance / equipment failure andOE information.

Fig. 2. WM process Model35

TEPCO’s Work Management Initiatives

Figure 3 shows Prioritization Matrix used in Screening phase, which is based on INPO’s AP-928.
Depending on the Significance and Type of Work, equipment is classified into four priority categories,and target work completion dates set.

Fig. 3. Prioritization Matrix

2.3.

WM Process and IT Support

An EAM software was introduced in 2014 to provide IT support for WM, Facility and Corrective
Action Program (CAP). An EAM software uses Work Order (WO) to manage status of maintenancework plan by each equipment, and is also used to accumulate Operating Experiences and workrecords.

Fig. 4. WM process and IT Support36

TEPCO’s Work Management Initiatives

2.4. Development of Functional Equipment Group（FEG）
A functional equipment group (FEG) is defined as "a group consisting of a main component
and subcomponents, within shared isolation boundary or fixed position". Isolation boundary is definedby work duration, target, function, content of work, etc. with all activities performed within thedefined boundary. Equipment in FEG is maintained at once during the execution phase.

Fig. 5. Functional Equipment Group（FEG）

2.5. Work Window（WW）Establishment
WW is a work period. Equipment is allocated to WW by FEG. Duration of a WW is one monthand One WW cycle is one year. The time frame during which safety systems and power supply
facilities are set out-of-service is assigned to WWs.

Fig. 6. Work Window（WW）

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TEPCO’s Work Management Initiatives

2.5.1. Safety Systems taken out of service at KK unit 1-5
Figure 7 shows safety systems A/B at KK units 1-5 assigned to WW to minimize D/Gunavailability. When assigning to WW, following two points are carefully considered.
Point1：Systems A/B are not removed from service at the same time to avoid loss of loading function.
To prevent systems A/B being out of service simultaneously, an interval is secured in case theout-of-service duration is extended.
Point2：System B of other unit is not assigned to a WW following a WW during which system B of agiven unit is out of service. By that, we avoid four D/Gs being out of service in case the out-of-service
duration is extended.

Fig. 7. KK units 1-5 safety systems A/B are assigned to WW to minimize D/G unavailability

2.6

Evaluation by Performance Indicator

During critique phase, we evaluate responses to safety risks, effectiveness of the process, andlessons learned, in order to utilize the results in our next planning. Effectiveness of the process isevaluated by following Performance Indicators (PIs). These PIs are counted up using IT system.
Table 1 Example of Performance Indicator (PI) for KK Units 1-538

TEPCO’s Work Management Initiatives

2.6.1. Evaluation of Past Performance
Figure 8 shows PI: Unavailability rate of HP/LP systems and emergency power supply during
plant shut-down. In 2017 when we launched WM, the PI was exceeding target. However in 2018 WM
process was established at KK site, and the PI showed improvement.

Fig. 8. PI：Unavailability rate of HP/LP systems and emergency power supply during plant shut-down

3.

Conclusion

TEPCO has conducted gap analysis by comparing its existing maintenance business processes
with the INPO’s AP guidelines and has arranged WM process flow, PI, duration of a WW etc. to fit
our business processes.
Efforts we placed on work management have resulted in improvements in setting and managing
the duration of safety-equipment unavailability and in addressing non-conformance backlogs, which
we believe to have contributed to enhanced safety. TEPCO is determined to continuously makeimprovements to minimize safety risks and to improve efficiency by managing risks.

References[1] Electric Utility Cost Group: EUCG Standard Nuclear Performance Model (2007).
[2] Institute of Nuclear Power Operations: Online Work Management Process Description, INPO’s AP-928(2016).

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