atw 2018-02

inforum

atw Vol. 63 (2018) | Issue 2 ı February

OPERATION AND NEW BUILD 102

can be used for OMA for manual

disconnection or operations.

To prevent equipment malfunction

due to fire-induced cable damage, a

fire alarm in FZ 1W signals the control

room to initiate the first safe shutdown

path using Series A cables.

Similarly, a fire alarm in FZ 1E signals

the control room to initiate the second

safe shutdown path using Series B

cables. On-duty staff must take the

actions presented in Table 6.

FZ 17 contains mainly Series B

cables as well as 11 Series A cables.

The post-fire hot shutdown cable list

(Table 7) revealed there is no way to

re-route the cable paths. At this point

10b can be used for OMA for manual

disconnection or operations.

A fire alarm in FZ 17W signals the

control room to initiate the first safe

No.

| | Fig. 5.

Conformity to regulations in chart form.

No. Cable No. SSD

Code

SSD

Equipment No.

Status

1 B-EF-HV203 ON

2 B-EF-HV206 ON

3 B-EF-HV221 ON

4 B-EF-HV222 OFF

5 B-EF-HV230 OFF

| | Tab. 8.

Valve states in hot shutdown mode.

Cable

Code

SSD Equipment

No.

SSD

Path

shutdown path using Series A cables.

A fire alarm in FZ 17E signals the

control room to initiate the second

safe shutdown path using B cables.

On-duty staff must take the actions

presented in Table 8.

The application of TRIZ requires

that the following conditions be

satisfied: At least one of the wire series

has avoided fire damage. For the sake

of simplicity, we adopted two inventive

principles: finding local properties

and taking preliminary actions.

Nuclear power regulation 10 CFR

50.48 APP.R stipulates that any wiring

essential to post-fire hot shutdowns

that passes through the same fire zone

require sufficient shielding to protect

them from fire for at least three h.

They must also be separated at least

20 ft, and automatic fire detection

and extinguishing systems must be

installed in the fire zone in question.

All wiring is expected to comply

with these regulations; however, prior

to modifications based on the proposed

method, 22 of the wires in

Series B were non-compliant. This

situation could not be foreseen without

integration of 850,000 pieces of

path data via knowledge management.

Among the 22 wires, 11 were

re-laid and within a fire compartment,

thereby reducing the number of

non-compliant wires to 11. According

to the principle of preliminary action,

the remaining 11 wires were deemed

not to affect post-fire hot shutdown

performance; therefore, even these 11

wires can be said to comply with

regulations.

Regulations stipulate that the

control room or emergency control

station be equipped with a series of

hot shutdown systems capable of

maintaining hot shutdown conditions

in the event of a fire in Fire Zones 1

and/or 17.

SSD

Cable Type

Raceway

No.

1 B1EEFHBCBSB H2 939 B-EF-HV230 HSD-P2 HSD-S B1EZJF4TPBA SE

2 B1EEFHBCBSD H2 939 B-EF-HV230 HSD-P2 HSD-S B1EZJF4TPBA SE

3 B1EEFHBCBSE H2 939 B-EF-HV230 HSD-P2 HSD-S B1EZJF4TPBA SE

4 B1EEFHBCJSA H2 C77 B-EF-HV206 HSD-P2 HSD-S B1EZJF4TPBA SE

5 B1EEFHCC8SA H2 C27 B-EF-HV203 HSD-P2 HSD-S B1EZJF4TPBA SE

6 B1EEFHCC8SB H2 C27 B-EF-HV203 HSD-P2 HSD-S B1EZJF4TPBA SE

7 B1EEFHCC8SC H2 C27 B-EF-HV203 HSD-P2 HSD-S B1EZJF4TPBA SE

8 B1EEFHCC9SA H2 C27 B-EF-HV222 HSD-P2 HSD-S B1EZJF4TPBA SE

9 B1EEFHCC9SB H2 C27 B-EF-HV222 HSD-P2 HSD-S B1EZJF4TPBA SE

10 B1EEFHCC9SC H2 C27 B-EF-HV222 HSD-P2 HSD-S B1EZJF4TPBA SE

11 B1EEFHCCASA H2 C77 B-EF-HV221 HSD-P2 HSD-S B1EZJF4TPBA SE

| | Tab. 7.

Series A cables in fire compartment 17 for safe hot shutdown.

Rway

Code

Fire compartments capable of

withstanding fire for three hours were

installed between post-fire safe hot

shutdown wires. The wires were

horizontally separated by at least 20 ft

and automatic fire detection and

extinguishing systems were installed.

Following these improvements in Fire

Zones 1 and 17, the post-fire safe hot

shutdown wires were in full compliance

with regulations (Figure 5).

Number of cables that do not

comply with regulations ≠ Estimated

number of cables that do not comply

with regulations = “Do not comply

with regulations”

Number of cables that do not

comply with regulations = Estimated

number of cables that do not comply

with regulations = “Comply with

regulations”

Number of non-complaint cables in

case study nuclear power plant = 0

5 Conclusions

This study applied TRIZ and

knowledge management to an actual

nuclear power plant in order to

bring the facility up to regulatory

minimums. Problems were identified

using hierarchy analysis in conjunction

with knowledge management for

the construction of a database. We

then identified elements that failed to

meet current regulations. TRIZ was

used to identify optimal solutions in

order to minimize the costs involved

in making improvements to existing

nuclear power plants.

The database of wires and circuits

essential to post-fire safe shutdown

operations enables operators to

identify affected systems and decide

whether immediate isolation is

required. The implementation of fire

zones makes it easy to determine

whether a zone lies along a safe

shutdown path. The proposed method

Operation and New Build

The Application of Knowledge Management and TRIZ for solving the Safe Shutdown Capability in Case of Fire Alarms in Nuclear Power Plants ı Chia-Nan Wang, Hsin-Po Chen, Ming-Hsien Hsueh and Fong-Li Chin

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