ML20071L168
| ML20071L168 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 07/22/1994 |
| From: | NORTHEAST NUCLEAR ENERGY CO. |
| To: | |
| Shared Package | |
| ML20071L163 | List: |
| References | |
| NUDOCS 9408020237 | |
| Download: ML20071L168 (10) | |
Text
I t
Docket No. 50-423 B14905 Millstone Unit No. 3 Proposed Revision to Technical Specifications Maximum Allowable Power Range Neutron Flux High Setpoint with Inoperable Main Steam-Line Safety Valves Marked-Up Pages July 1994 9400020237 940722 PDR ADOCK 05000423 P
~
q TABLE 3.7-1
' YAN-3 M 986~
MAXIMUM ALLOWABLE POWER RANGE NEUTRON FLUX HIGH SETPOINT WITH INOPERABLE STEAM LIhE SAFETY VALVES DURING FOUR LOOP OPERATION e
HAXIMUM NUMBER OF INOPERABLE MAXIMUM ALLOWABLE POWER RANGE SAFETY VALVES ON ANY NEUTRON FLUX HIGH SETPOINT OPERATING STEAM GENERATOR (PERCENT OF RATED THERMAL POWER)
I i
1
@ GS--
2 h 2$
3 t
4 TABLE 3.7-2 MAXIMUM ALLOWABLE POWER RANGE NEUTRON FLUX HIGH SETPOINT WITH INOPERABLE STEAM LINE SAFETY VALVES DURING THREE LOOP OPERATION MAXIMUM NUMBER OF INOPERABLE MAXIMUM ALLOWABLE POWER RANGE SAFETY VALVES ON ANY NEUTRON FLUX HIGH SETPOINT OPERATING STEAM GENERATOR *
(PERCENT OF RATED THERMAL POWER)
I h
47 f
2 33 3
h l3 4
l DAt least two safety valves shall be OPERABLE on the non-operating steam i
generator.
l 9
}
MILLSTONE - UNIT 3 3/4 7-2
i 3/4.7 PLANT SYSTEMS
-p_JAN'3 H986
(
BASES 1
3]4.7.1 TURBINE CYCLE 3/4.7.1.1 SAFETY VALVES The OPERABILITY of the main steam line Code safety valves ensures that the Secondary System pressure will be limited to within 110% (1305 psig) of its design pressure of 1185 psig during the most severe anticipated system operational transient.
The maximum relieving capacity is associated with a Turbine trip from 100% RATED THERMAL POWER coincident with an assumed loss of condenser heat sink (i.e., po steam bypass to the condenser).
cM 4.q ~ M w w The specified valve(lift settings and relieving capacities are in accordance with the requ'rements of Section III of the ASME Boiler and Pressure Code, 1971 Edition.
Th total relieving capacity for all valves on all of the 7 lbs/h which is 105% of the total secondary steam flow steam lines is 1.579 X of 1.504 X 107 lbs/h at 100% RATED THERMAL POWER.
A minimum of two OPERABLE safety valves per steam generator ensures that sufficient relieving capacity is available for the allowable THERMAL POWER restriction in Table 3.7-2.
STARTUP and/or POWER OPERATION is allowable with safety valves inoperable within the limitations of the ACTION requirements on the basis of the reduction in Secondary Coolant System steam flow and THERMAL POWER required by the The
(
reduced Reactor trip settings of the Power Range Neutron Flux channels.
Reactor Trip Setpoint reductions are derived on the following bases:
For-four-loop-operation SP = (X) - (Y)(V) x 109 X
h For three lo ration Sp,(X) - (Y3tU) 80 X
Where:
SP = Reduced ctor Trip Setpoint in pe nt of RATED TF 9 MAL i
POW V - Maximum number of inoperable safety valves per am lin, U = Maximum number of inoperable safety valves per operati stee= m.
e
(
MILLSTONE - UNIT 3 8 3/4 7-1
[\\nwk.d Wo.
W
=
i emer o w ar e. - w. m.
.eusimp e.wammess e -, emi 43
.-e-es
...a 5
~
V-JAN-3 H986-PLANT SYSTEMS BASES' I
!^fET V^.LVES (Ccntinecd)
- Power Range Neutron Flux-High Trip Setpoint f ur loop pe tion, 80 =
Maximum perce f RATED T POWER permissible by P-8 Setpoint for t oop operation, j
X =
Total r ng capacity of al ty valves per steam n 1bs/ hour, and Y =
ximum relieving capacity of any one safety valve 3/4.7.1.2 AUXILIARY FEEDWATER SYSTEM s
The OPERABILITY of the Auxiliary Feedwater System ensures that the Reactor Coolant System can be cooled down to less than 350'F from normal operating or accident conditions coincident with a total loss-of-offsite power.
The auxiliary feedwater system is capable of delivering a total feedwater flow of 480 gpm at a pressure of 1236 psia to the entrance of at least three steam generators while allowing for (1) any spillage through the design worst-case break of the Normal feedwater line, (2) the design worst-case single fail-ure; and (3) recirculation flow.
This capacity is sufficient to ensure that i
adequate feedwater flow is available to remove decay heat and reduce the Reactor Coolant System temperature to less than 350*F at which point the Residual Heat Removal System may be placed into operation.
t 3/4.7.1.3 DEMINERALIZED WATER STORAGE TANK The OPERABILITY of the demineralized water storage tank with the minimum water volume ensures that sufficient water is available to maintain the RCS at HOT STANDBY conditions for 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> with steam discharge to the atmosphere concurrent with total loss-of-offsite power, and with an additional 6-hour cooldown period to reduce reactor coolant temperature to 350*F.
The contained water volume limit includes an allowance for water not usable because of tank discharge line location or other physical characteristics, 3/4.7.1.4 SPECIFIC ACTIVITY The limitations on Secondary Coolant System specific activity ensure that the resultant offsite radiation dose will be limited to a small fraction of 10 CFR Part 100 dose guideline values in the event of a steam line rupture.
This dose also includes the effects of a coincident 1 gpm primary-to-secondary tube leak in the steam generator of the affected steam line.
These values are consistent with the assumptions used in the safety analyses.
M'.LLSTONE - UNIT 3 8 3/4 7-2
{\\m,v.v<un Du
o, INSERT A Hi $ = (100/0) where:
Hip - Safety Analysis power range high neutron flux setpoint, percent Q
- Nominal NSSS Jower rating of the plant (including reactor coolant pump leat), Mwt K
- Conversion factor, 947.82 (Btu /sec)
Mwt h,, - heat of vaporization for steam at the highest MSSV opening l
pressure including tolerance (13%) and accumulation, as appropriate, Btu /lbm N
- Number of loops in plant w,
- Minimum total steam flow rate capability of the operable MSSVs on any one steam generator at the highest MSSV opening pressure including tolerance and accumulation, as appropriate, in 1b/sec.
i for example, if the maximum number of inoperable MSSVs on any one steam generator is one, then w, should be a summation of the capacity of the operable MSSVs at the highest operable MSSV operating pressure, excluding the highest capacity MSSV.
If the maximum number of inoperable MSSVs per steam generator is three, then w, should be a summation of the capacity of the operable MSSVs at the highest operable MSSV operating pressure, excluding the three highest capacity MSSVs. The following plant specific safety valve flow rates were used:
SG Safety Main Steam System Valve Number (Bank No.)
Set Pressure (psia)
Flow (1bny'hr per loop) i 1
1200 893,160 2
1210 900,607 3
1220 908,055 4
1230 915,502 5
1240 922,950
.. =
a, Docket No. 50-423 B14905 i
i i
Millstone Unit No. 3 Proposed Revision to Technical Specifications Maximum Allowable Power Range Neutron Flux High Setpoint with Inoperable Main Steam-Line Safety Valves Retyped Pages July 1994
o.
TABLE 3.7-1 MAXIMUM ALLOWABLE POWER RANGE NEUTRON FLUX HIGH SETPOINT WITH INOPERABLE STEAM LINE SAFETY VALVES DURING FOUR LOOP OPERATION MAXIMUM NUMBER OF INOPERABLE MAXIMUM ALLOWABLE POWER RANGE SAFETY VALVES ON ANY NEUTRON FLUX HIGH SETPOINT OPERATING STEAM GENERATOR (PERCENT OF RATED THERMAL POWER)
I I
65 2
46 3
28 TABLE 3.7-2 MAXIMUM ALLOWABLE POWER RANGE NEUTRON FLUX HIGH SETPOINT WITH INOPERABLE STEAM LINE SAFETY VALVES DURING THREE LOOP OPERATION
]
MAXIMUM NUMBER OF INOPERABLE MAXIMUM ALLOWABLE POWER RANGE SAFETY VALVES ON ANY NEUTRON FLUX HIGH SETPOINT OPERATING STEAM GENERATOR *
(PERCENT OF RATED THERMAL POWER)
I 47 2
33 3
19
- At least two safety valves shall be OPERABLE on the non-operating steam generator.
1 l
MILLSTONE - UNIT 3 3/4 7-2 Amendment No.
0273
.,a 3/4.7 PLANT SYSTEMS BASES 3/4.7.1 TURBINE CYCLE 3/4.7.1.1 SAFETY VALVES The OPERABILITY of the main steam line Code safety valves ensures that i
the Secondary System pressure will be limited to within 110% (1305 psig) of its design pressure of 1185 psig during the most severe anticipated system operational transient. The maximum relieving capacity is associated with a Turbine trip from 100% RATED THERMAL POWER coincident with an assumed loss of condenser heat sink (i.e., no steam bypass to the condenser).
The specified valve lift settings and relieving capacities are in accordance with the requirements of Section III of the ASME Boiler and Pressure Code, 1971 Edition. The design minimum total relieving capacity for all valves on l 7
all of the steam lines is 1.579 X 10 lbs/h which is 100% of the total secondary 7
steam flow of 1.504 X 10 lbs/h at 100% RATED THERMAL POWER. A minimum of two OPERABLE safety valves per steam generator ensures that sufficient relieving capacity is available for the allowable THERMAL POWER restriction in Table 3.7-2.
l 4
STARTUP and/or POWER OPERATION is allowable with safety valves inoperable within the limitations of the ACTION requirements on the basis of the reduction in Secondary Coolant System steam flow and THERMAL POWER required by the reduced Reactor trip settings of the Power Range Neutron Flux channels. The Reactor Trip Setpoint reductions are derived on the following bases:
Hi $ = (100/0) where:
Hip - Safety Analysis power range high neutron flux setpoint, percent i
Q
- Nominal NSSS power rating of the plant (including reactor coolant pump heat), Mwt K
- Conversion factor, 947.82 (Btu /sec)
Mwt hg - heat of vaporization for steam at the highest MSSV opening pressure including tolerance (13%) and accumulation, as i
appropriate, Btu /lbm N
- Number of loops in plant i
MILLSTONE - UNIT 3 B 3/4 7-1 Amendment No.
0274
. i e,
PLANT SYSTE]i1 BASES SAFETY VALVES (Continued) w,
- Minimum total steam flow rate capability of the operable MSSVs on any one steam generator at the highest MSSV opening pressure including tolerance and accumulation, as appropriate, in 1b/sec.
For example, if the maximum number of inoperable MSSVs on any one steam generator is one, then w, should be a summation of the capacity of the operable MSSVs at the highest operable MSSV operating pressure, excluding the highest capacity MSSV.
If the maximum number of inoperable MSSVs per steam generator is three, then w, should be a summation of the capacity of the operable MSSVs at the highest operable MSSV operating pressure, excluding the three highest capacity MSSVs. The following plant specific safety valve flow rates were used:
SG Safety Main Steam System Valve Number (Bank No.)
Set Pressure (psia)
Flow (1bm/hr per loop) 1 1200 893,160 2
1210 900,607 3
1220 908,055 4
1230 915,502 5
1240 922,950 3/4.7.1.2 AUXILIARY FEEDWATER SYSTEM The OPERABILITY of the Auxiliary Feedwater System ensures that the Reactor Coolant System can be cooled down to less than 350*F from normal operating or accident conditions coincident with a total loss-of-offsite power.
The auxiliary feedwater system is capable of delivering a total feedwater flow of 480 gpm at a pressure of 1236 psia to the entrance of at least three steam generators while allowing for (1) any spillage through the design worst-case break of the Norr-1 fa;owater line, (2) the design worst-case single fail-ure; and (3) recirculacon flow. This capacity is sufficient to ensure that adequate feedwater fisw is available to remove decay heat and reduce the Reactor Coolant System temperature to less than 350*F at which point the Residual Heat Removal System may be placed into operation.
MILLSTONE - UNIT 3 B 3/4 7-2 Amendment No.
0214
PLANT SYSTEMS BASES SAFETY VALVES (Continued) 3/4.7.1.3 DEMINERALIZED WATER STORAGE TANK The OPERABILITY of the demineralized water storage tank with the minimum water volume ensures that sufficient water is available to maintain the RCS at HOT STANDBY conditions for 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> with steam discharge to the atmosphere concurrent with total loss-of-offsite power, and with an additional 6-hour cooldown period to reduce reactor coolant temperature to 350*F. The contained water volume limit includes an allowance for water not usable because of tank discharge line location or other physical characteristics.
3/4.7.1.4 SPECIFIC ACTIVITY The limitations on Secondary Coolant System specific activity ensure that the resultant offsite radiation dose will be limited to a small fraction of 10 CFR Part 100 dose guideline values in the event of a steam line rupture.
This dose also includes the effects of a coincident I gpm primary-to-secondary tube leak in the steam generator of the affected steam line. These values are consistent with the assumptions used in the safety analyses, i
1 MILLSTONE - UNIT 3 B 3/4 7-2a Amendment No.
0274 j