ML20238E917

Proposed Tech Specs,Changing Control Blade Withdrawal & Adding Shutdown Margin & Regulating Blade Worth to Safety Limits

ML20238E917
Person / Time
Site:	05000134
Issue date:	09/10/1987
From:	WORCESTER POLYTECHNIC INSTITUTE, WORCESTER, MA
To:
Shared Package
ML20238E910	List: ML20238E907 ML20238E917
References
NUDOCS 8709150291
Download: ML20238E917 (2)

Text

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ep 2.0 ' SAFETY LIMITS AND'0PERATING RESTRICTIONS 2.1 Safety Limits Criticality: The' reactor shall be subcritical when the three control blades are at their fully 1:ithdrawn positions and the regulating blade is in its. fully inserted position.

Shutdown Mergin:

The minimum shutdown margin under any condition with the highest worth control blade fully withdrawn shall be no less than 1% Ak/k.

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Magnet Release and Blade Drop Times: The interval between the occurrence

.F, of cutoff voltage (scram) and the separation of each control blade from its

- magnet shall not exceed 100 msec. Total time of insertion of the first 24 in, of the control _ blades following initiation of a scram signal shall be

[ce less than 600 msec, including the magnet release time.

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Maximum Excess Reactivity: The maximum excess reactivity above cold, clean, critical shall be 0.5% Ak/k.

Radiation Alarms: Upon indication of radiation levels in excess of 50 mrems/hr (20 mrems/hr for fuel storage) area rianitors shall actuate audible

- evacuation alarms < in the reactor room and in the second and third floor areas above the. reactor pool.

Radiation Levels:

The maximum rediation levels 1 m above the pool surface and at the surface of the concrete shield, when the beam port and' thermal column ~ are closed, shall be'less than 50 mrems/hr.

Control Blade Withdrawr,1: the maximum withdrawal rate for.a control blade i

shall be 7.5 in./ min. ?The maximum reactivity addition ratt through move-1 ment of. the regulating blade shall be 0.006% Ak/k sec.

Interlocks shall p

prevent simultaneous withdrawal of more than one control blade and shall d

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Y prevent withdrawal. of any control blade unless the regulating blade is T(

fully inserted.

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Regulating Blade Worth: The regulating blade shall have a reactivity worth of less.than the effective delayed neutron fraction.

Startup Source Requirement: Ouring reactor startup, a neutron source producing at least 10 neutrons /sec shall be located adjacent to the fuel region.- When readings on the log count rate meter are below 50 counts /sec, 1

an interlock shall prevent withdrawal of any control blade.

Temperature and Void Coefficients: Thetemperatureandgoidcoefficients of reac6v~Eishall-be more neggtive than -2 x 10~5 k/k F and -2 x 10~8 A k/k %. void,nmspectively, at 80 F.

Water Level: The minimum depth of water above the top of the end box of the core Fiel elements.in the reactor pool shall be 10 f t.

i Water Puritv: Corrective action shall be taken promptly if the following Timits TEF'the pool water are not met:

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Worcester Tech Specs 3

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'I (1) startup channel, background to'10-2%, full power, i.e.,Taackground to 1 W.

-(2) log-N period channel: 2 x 10 % to 150% full power; i.e.., 0.2 W.to 13 kW (3) Linear safety channels 1 aad 2; 2 x 10~3% to 150% full power; Ne.,

0.2 W to 15 kW 4.5.2 Control Blades m

..There shall be three control blades, tvch consisting of vertical y

aluminum-clad boral blades 10.5 in. wid2 x 40.5 in. long x 0.375 in thick.

4.5.3 Regulating Blade t

m There shall be one regulating blade consisting of 'a vertical stainir.ss-steel blade 10.65 in wide x 40.51r,. long x 0.125 in. thick.

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4.5.4 Blade Position I'ndicators The blade position indicator on tne consolec shall provide an indication of the blade position to within +.02 dn. ' Signal lights shall be proviced for each control blade drive and for the regulating; blade to indicate the upper and lower limits of travel and, in the case of control blades, an armatcre engaged by a magnet.

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9 Worcester Tech Specs

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