ML16095A080
ML16095A080 | |
Person / Time | |
---|---|
Site: | Wolf Creek ![]() |
Issue date: | 04/12/2016 |
From: | Morris J Enercon Services |
To: | Plant Licensing Branch IV |
Lyon C F, NRR/DORL/LPLIV-1 | |
References | |
CAC MC4731 WCN-021-DSPEC-001, Rev 0B | |
Download: ML16095A080 (45) | |
Text
WCN-021-DSPEC-0011 Does this Design Specification contain any open assumptions, including preliminary information that require confirmation? (If , Identify the assumptions.) 2 Does this Design Specification supersede an existing Design Specification? (If , Identify the superseded Design Specification.) Initial Issue (Enter Name and Sign) Note 1: Design Verification is required for all safety-related Design Specifications.
WCN-021-DSPEC-0010B Initial Issue A 1 to 9 0B WCN-021-DSPEC-001 572.1 WCGS Strainer ............................................................................................................... 7 2.2 Sump Pool Volume ......................................................................................................... 13 2.3 Sump Pool Boron Concentration and pH ........................................................................ 14 2.4 Strainer Surface Area and Flow Rate ............................................................................. 14 2.5 Fibrous Debris Type and Quantity .................................................................................. 14 1617185.1 Fiber Type ...................................................................................................................... 19 5.2 Test Water Chemistry ..................................................................................................... 21 5.3 Fiber Concentration ........................................................................................................ 21 5.4 Fluid Temperature .......................................................................................................... 22 5.5 Approach Velocity........................................................................................................... 22 5.6 Test Cases ..................................................................................................................... 23 236.1 Requirements on Test Apparatus ................................................................................... 23 6.2 Requirements on Test Preparation ................................................................................. 26 6.3 Requirement on Test Control .......................................................................................... 28 31313132 ZOI Fibrous Debris Preparation .................................................................................................... 9 Design Specification Preparation Checklist ................................................................................... 2 Design Verification Plan and Summary Sheet ............................................................................... 1 Design Verification Checklist ......................................................................................................... 1 WCN-021-DSPEC-001
...................................................................... 5 Figure 2: WCGS Containment Sump Strainer System Elevation View (Ref. 3.11).................................... 6 Figure 3: 7 Disk Module and 11 Disk Module (Ref. 3.12) ......................................................................... 8 Figure 4: Sump A Strainer Plan and Section Views (Ref. 3.11 and 3.13) ................................................. 9 Figure 5: Wire Grill Details (Ref. 3.16) .................................................................................................... 10 Figure 6: Gap Disk Details (Ref. 3.16) .................................................................................................... 10 Figure 7: Isometric view of Wolf Creek lower containment (Ref. 3.30) .................................................... 12 Figure 8: CAD model view of sump geometry (Ref. 3.30) ....................................................................... 12 Figure 9: Sump water source streamlines (Ref. 3.30) ............................................................................ 13 Table 1: Material Characteristics of Fiber Types (Ref. 3.21, Table 5.1) .................................................. 15 Table 2: Bounding Fibrous Debris Quantities at the Strainer for Wolf Creek (Ref. 3.27) ......................... 15 Table 3: Fiber Penetration Test Variables (values derived in Sections 0 through 5.5) ............................ 18 Table 4: WCGS and PBNP Parameter Comparison ............................................................................... 19 Table 5: Parameter Comparison for WCGS and CCI Small-Scale Testing ............................................. 20 Table 6: NUREG/CR-6224 Description of Processed Fiber Classes (Ref. 3.3) ...................................... 28 Table 7: Required Debris Surrogate Quantities (Ref. 3.27) .................................................................... 29
WCN-021-DSPEC-001 During the sump recirculation phase after a loss-of-coolant accident (LOCA), the emergency core cooling system (ECCS) and containment spray (CS) pumps take suction from the containment sump and pump coolant to the reactor core and containment atmosphere, respectively. Fibrous and particulate debris, which consists of failed insulation and coatings, and latent debris could transport to the sump strainer. Some of this debris could then penetrate the strainer perforated plates and impose downstream effects on the ECCS and CS pumps and other components along the recirculation flow path. In order to determine the potential downstream effects, testing must be performed to quantify fibrous penetration. Figures 1 and 2 show the layout of the Wolf Creek Generation Station (WCGS) containment sump recirculation strainers designed by Performance Contracting Incorporated (PCI). The strainer system prevents the passage of debris to the suction lines of the ECCS and CS pumps through the two containment recirculation sumps referred to as A Sump (North) and B Sump (South) (Ref. 3.11).
WCN-021-DSPEC-001 While the majority of the fibrous debris can be filtered out by the strainers, some debris will penetrate1 be determined experimentally for Wolf Creek. The large-scale penetration testing shall be performed on a modified Wolf Creek strainer module to quantify the amount of fiber penetration at the plant. The results will then be used as part of the response to Generic Letter 2004-02 (Ref. 3.2). Due to the similarity between the WCGS strainers and the strainers at NextEra Point Beach Nuclear Plant (PBNP), the results from PBNP small-scale testing will be used to inform certain parameters of the large-scale testing at Wolf Creek. These parameters include water chemistry, fiber concentration, and modifications to mitigate fiber bridging. A comparison of these parameters is provided in Table 4 of Section 5.0. The approach velocity and water temperature parameters for the large-scale testing at Wolf Creek will be informed by the small-scale testing completed for the Pressurized Water Reactor Owner3.6. Using the combination of the results from PBNP small-scale testing and the PWROG small-scale testing, the large-scale test parameters at Wolf Creek can be fully informed. Therefore, small-scale testing at Wolf Creek will be forgone. Particulate debris shall not be used in the penetration testing. This is conservative because as a fiber bed forms on the strainer, introduction of particulate would serve to hasten bed formation and inhibit further fiber penetration. This is because fiber serves to entrap particulates within the fiber bed. A 1/8 inch fiber bed is sufficient to cause accumulation of a low-permeability granular 1 This occurrence is also referred to as fiber bypassing the strainer.
WCN-021-DSPEC-001 layer of particulate debris atop the fiber bed. This causes an increased pressure drop across the debris bed which serves to further compress the fiber bed and inhibit penetration (Ref. 3.4, Page 3-67). Thus, exclusion of particulate debris serves as a conservatism for fiber penetration measurement. In addition, if particulates were added to the test, they would pass through the strainer and collect in the capture filters. This would prevent accurate measurements of the fiber mass since it is not practical to separate the particulates from the fibers (Ref. 3.4, Page 3-37). This document develops the safety-related test specification for the large-scale fibrous debris penetration testing to be conducted by Alden Research Laboratory, Inc. (referred to as Alden -scale fibrous debris penetration test plan and implementation procedures, which are to be conducted in accordance with the test protocol proposed in Reference 3.8 and addressed by the NRC in Reference 3.9. As discussed above, the conservative conditions identified by small-scale tests from the PWROG and PBNP are used to inform the large-scale test parameters at Wolf Creek. The outputs of the large-scale testing shall be used to determine the quantity of fiber that will penetrate the containment sump strainers in the event of a LOCA. This test specification does not address sizing and design of the test strainer, which shall be finalized in the Alden test plan. As a result, the following quantities must be determined in the Alden test plan: 1. Test flow rate 2. Maximum allowable size for piping between test strainer and filter housings in order to meet the requirements provided in Section 6.1.3. 3. Total number of debris batches required 4. Debris introduction time for each debris batch 5. Test debris quantity This section presents the required test inputs obtained from existing plant documents for Wolf Creek strainer configuration, flow rate, sump pool parameters and debris loads. 2.1.1. Strainer Configuration There are two groups of vertically oriented strainer assemblies that fit into each of the two sumps, designated A and B, at WCGSECCS and CS systems and are fed by two independent strainer assemblies (Ref. 3.11). The strainer assemblies are identical with respect to design, surface area, orientation, design flow, and configuration. Each strainer train is comprised of sixteen strainer stacks with 4 inch gaps of separation between adjacent strainer stacks and between the end strainer stacks and pit walls WCN-021-DSPEC-001 (Ref. 3.11). There are two types of strainer stacks, Type A and Type B, of which there are eight of each in a single strainer assembly. Type A stacks are comprised of three modules with eleven disks and one module with seven disks, while Type B stacks are comprised of five modules with eleven disks each, as seen in Figure 4 (Ref. 3.11, 3.13). The major components of a module are end strainer disks (those at the top and bottom of a module), intermediate strainer disks, gap disks, and a core tube. A distance of 3 inches separates the end disk faces of adjacent modules within a stack. Both the 7-disk and 11-disk modules are shown in Figure 3 (Ref. 3.12).
WCN-021-DSPEC-001 Intermediate strainer disks are composed of two perforated plates that sandwich a wire grill and are connected about their perimeter by a perforated rim disk. The perforated plates of both the disk faces and the rim disk are 22 ga. ASTM A240 type 304 stainless steel with 0.045 inch diameter holes on 0.081 inch staggered centers (Ref. 3.18). 3.14 and 3.15) and are separated by a 1/2 inch gap from the inside of each perforated plate, which is the width of the rim disk as well as the wire grill (Ref. 3.16). This results in a total disk thickness of 0.558 inches (Ref. 3.14 and 3.15). The wire grill configuration is detailed in Figure 5.
WCN-021-DSPEC-001 Gap disks share the same base material, sheet thickness, and perforation pattern as the disk face and rim disk perforated plates. They have an outer diameter of 10.063 inches and surround the core tube, spanning the 1 inch gap between adjacent strainer disks (Ref. 3.16). As seen in Figure 6, only 0.675 inches of the 1 inch gap is perforated.
WCN-021-DSPEC-001 The core tube has an outer diameter of 7.5 inches and is broken into sections, where one section of core tube belongs to each strainer stack module. Flow that penetrates the strainer disks and gap disks enters the core tube through rectangular perforations. The core tube is perforated with a row of four holes for each disk which are evenly spaced about its circumference so that the centers of adjacent holes are 90 degrees apart. The dimensions of the holes (width x length)vary continually through all sections of a stack, increasing in area from bottom (nearest the plenum) to top (Ref. 3.17). The bottom of the core tubes interface with the top of the plenum. The plenum is located at the bottom of the sump and has two sections which have no barrier between them. The first section, on which the Type B strainer stacks sit, has a clearance - from the bottom of the sump. The second section, on which the Type A strainer stacks sit, has a clearance - from the bottom of the sump, which provides space for the ECCS suction pipes (see Figure 2). The Residual Heat Removal (RHR) and CS systems have independent pipes that protrude into the plenum and draw flow; the RHR suction is via a 14 inch diameter line and the CS suction is via a 12 inch diameter line (Ref. 3.13). 2.1.2. Strainer Location and Recirculation Flow Path As shown in Figure 7, the Wolf Creek sump strainers are located just outside of the bioshield wall and are separated by a wall that extends out from the bioshield wall for the full length of the sump pit (Ref. 3.30, Page 47, 76). A top cover rests overhead the sump strainers, approximately -3.11) above the containment floor, but since this is above the Large Break LOCA (LBLOCA) sump water level, it will not affect debris transport. The sump pits are also surrounded However, the debris transport effects of these curbs were accounted for in the debris transport calculation (Ref. 3.30), and therefore do not need to be modeled in the penetration testing.
WCN-021-DSPEC-001 The area within the bioshield wall is connected to the area outside by a set of four passages, two of which have debris barrier doors to prevent debris from passing through to the sumps. As a result, recirculation flow exits the area within the bioshield wall on the east end of containment, opposite from the sumps, and then flows to the sumps in the annulus. Figure 9 shows the path that the recirculation flow takes to each sump (Ref. 3.30, Page 120). In both sumps, the majority WCN-021-DSPEC-001 of the flow initially approaches from the north or south direction and then either enters the sump from the side of initial approach or circulates around the strainer until it enters the sump. The is 18,745 ft3 at the ECCS switchover. This volume equates to a minimum water level elevation 3.19, page 30). The minimum sump volume in the event of a LBLOCA has been conservatively calculated to be 35,339 ft3 at the ECCS switchover. This volume is obtained by taking the total volume above the -(Ref. 3.19, page 30). The corresponding at the CS switchover in the event of a LBLOCA is 23,031 ft3. This volume equates to a minimum water level elevation 3.19, page 32). The corresponding sump volume at the CS switchover in the event of a LBLOCA has been conservatively calculated to be 39,626 ft3. This volume is obtained by taking the total volume , , and the trenches below -43.19, page 32). The highest point of the strainer is the top of the coupling on the top modules, which is at an
-113/16 (Ref. 3.13). By subtracting the length of the coupling (21/23.12) and the thickness of the external debris stop (1/43.12) on which the coupling rests, the e-113/16 -111/16 . The resulting strainer submergence for a LBLOCA at the ECCS switchover is approximately 2,002.09 2, = 1.17 The resulting strainer submergence for a LBLOCA at the CS switchover is approximately 2,002.43 2,.
WCN-021-DSPEC-001 As shown in Reference 3.20 sodium hydroxide (NaOH) is used as the buffer to adjust the sump pool pH. The minimum long-term post-LOCA recirculation sump pool pH of 8.73 results from a boron concentration of 2406 ppm and corresponding NaOH concentration of 2.7195 g/l (Ref.
3.20, Page 5). These conditions are taken for two-train eductor operation and a sump pool temperature of 86 °F. The maximum long-term post-LOCA recirculation sump pool pH of 9.62 results from a boron concentration of 2117 ppm and corresponding NaOH concentration of 4.5797 g/l (Ref. 3.28, Sheet 74-76). This maximum pH is calculated in Reference 3.28 using the provided boron and NaOH concentrations, assuming a sump temperature of 80 °F. The calculated surface area of the sump strainer assemblies is 3,311.5 ft2 each (Ref. 3.10). The maximum flow rate for an individual train during two train operation is 8750 gpm, consisting of an RHR pump flow rate of 4800 gpm and a CS pump flow rate of 3950 gpm. For the RHR pump, Reference 3.22 sized RHR orifices such that the maximum RHR pump flow rate is limited to 4800 gpm per pump. This criterion was met, as shown in Attachment 15 of Reference 3.23, which used a Fathom model and reported a maximum RHR pump flow of 4760 gpm. For the CS pump, Reference 3.31 determined a maximum flow rate of 3950 gpm by plotting the pump curve with the possible system curves. The same maximum flow rate is also shown in the pump curve found in the CS system description (Ref. 3.32). All flow rates presented above assume that two trains and all pumps are operational. Two train operation is considered when determining the strainer flow rate because it maximizes the amount of strainer surface area available for the fibrous debris to penetrate. For a given debris quantity, increasing the surface area available is conservative because there is more area available for penetration and the debris bed must cover more area, making it less dense and allowing for more penetration. Although the single train maximum RHR flow rate of 4880 gpm is 80 gpm higher than the two train maximum RHR flowrate presented above (Ref. 3.34), this increase has minimal impact of the approach velocity calculated in Section 5.5, and the increase in strainer surface area by assuming two train operation will have a larger impact on fiber penetration. Wolf Creek has the following fibrous debris types: Nukon, Antisweat blankets, Cerablanket, Thermo-Lag fire barrier, Darmatt fire barrier, and latent fiber. Material characteristics for these fiber types are summarized in Table 1 (Ref. 3.21, Table 5-1). Although Antisweat blankets and Darmatt fire barrier are fibrous debris types present at WCGS, neither of these materials are destroyed by the bounding Double Ended Guillotine Breaks (DEGBs) upstream of the first isolation valve (Ref. 3.27, Appendix 1). Therefore, these debris types will not be considered in penetration testing.
WCN-021-DSPEC-001 Debris Type Macroscopic Density (lbm/ft3) Characteristic Size (µm) Nukon 2.4 7.00 Antisweat Blankets 5.5 8.25 Cerablanket 8.0 3.20 Thermo-Lag 144.2 7.00 Darmatt 64.5 - 75.5 2.7 Latent Fiber 2.41F2 73 Table 2 shows the Wolf Creek fine fibrous debris quantities transported to the sump strainers (Ref. 3.27, Appendix 1). The total (Low Density Fiberglass (LDFG) and latent fiber) fiber mass is shown for the bounding Double Ended Guillotine Break (DEGB) cases that result in the most fiber transported to the strainer for various break sizes. Large-scale penetration tests will be performed with only fine debris. The fibrous fines debris quantities shown in Table 2 also include the quantity of fines generated due to erosion of small and large pieces of debris. These fines due to erosion are calculated for both settled debris, as well as debris transported to the strainer, and the calculation process is described in detail in the Debris Quantity Summary calculation (Ref. 3.27). As shown in the table, the maximum total fine fibrous debris amount results from a break in the steam generator loop D crossover leg (Ref. 3.21, Page 16) and is 485.6 lbm, which will be used to calculate the maximum sump pool debris concentration. The debris quantities presented in Table 2 are the maximum amounts that transport to the strainer in sump B, as presented in the Debris Quantity Summary calculation (Ref. 3.27, Appendix 1).Weld Name (Break Location) Compartment Pipe ID (in.) LDFG Fines (Includes Latent Fiber) (lbm) BB-01-S101-07 SG 1&4 8.75 51.5 EJ-04-F025 SG 1&4 10.5 82.9 BB-01-F001 SG 1&4 11.188 71.7 BB-01-S402-03 SG 1&4 11.5 77.4 BB-01-F201 SG 2&3 27.5 325.6 BB-01-F204 SG 2&3 29 470.9 BB-01-F405 SG 1&4 31 485.6 2 Per NEI 04-07 SER (Ref. 3.5, Page VII-3), the macroscopic density of latent fiber is 2.4 lbm/ft3. 3 See Assumption 4.1 WCN-021-DSPEC-001 3.1 Nuclear Energy Institute, Revision 1, January 2012. ML120481057. 3.2 NRC Generic Letter 2004-during Design Basis Accidents at Pressurized- ML042360586. 3.3 NUREG/CR-6224, "Parametric Study of the Potential for BWR ECCS Strainer Blockage Due to LOCA Generated Debris," October, 1995. 3.4 NEI 04-07, Volume 1, "Pressurized Water Reactor Sump Performance Evaluation ML050550138. 3.5 NEI 04-07, Volume 2, "Safety Evaluation by the Office of Nuclear Reactor Regulation Related to NRC Generic Letter 2004-02, Revision 0, December 6, 2004 Revision 0, December 2004. ML050550156. 3.6 AREVA Calculation 32-9217765- 3.7 ASTM D1193- 3.8 ML12228A330. 3.9 Generic Letter 2004- ML12121A384. 3.10 TDI-6002-01 / TDI-6003- Revision 3. 3.11 WCGS Drawing C-1016-00001, Rev. W03, [Vendor Drawing SFS-WC/CW-GA-00 Revision 3]. 3.12 WCGS Drawing C-1016-00006, Rev. W03, [Vendor Drawing SFS-WC/CW-PA-7100, Revision 3]. 3.13 WCGS Drawing C-1016-00003, Rev. W05, [Vendor Drawing SFS-WC/CW-GA-02, Revision 5]. 3.14 WCGS Drawing C-1016-00007, Rev. W05, [Vendor Drawing SFS-WC/CW-PA-7101, Revision 8]. 3.15 WCGS Drawing C-1016-00008, Rev. W06, [Vendor Drawing SFS-WC/CW-PA-7102, Revision 9]. 3.16 WCGS Drawing C-1016-00010, Rev. W04, [Vendor Drawing SFS-WC/CW-PA-7104, Revision 5]. 3.17 WCGS Drawing C-1016-00009, Rev. W04, [Vendor Drawing SFS-WC/CW-PA-7103, Revision 2]. 3.18 WCGS Drawing C-1016-00002, Rev. W05, [Vendor Drawing SFS-WC/CW-GA-01, Revision 8].
WCN-021-DSPEC-001 3.19 WES-009-CALC-/Callaway Post-LOCA Containment Water Level CalculationRevision 1. 3.20 EN-03-W-002- 3.21 WCN019-CALC-Debris Gen. (DRAFT) 3.22 EJ- 3.23 ARC- Revision 1. 3.24 EMG E-1, Loss of Reactor or Secondary Coolant6. 3.25 NEE-021-PI-001-Scale Fibrous Debris Penetration Test Plan for Point Beach Nuclear Plants Units 1 and 2 Containment Sump Strainers, Revision 0. 3.26 1142PBNBYP-R1-. 3.27 WCN019-CALC-. (DRAFT) 3.28 GS-M-. 3.29 1142PBNBYP-R2-Revision 0. 3.30 WCN019-CALC- (DRAFT). 3.31 EN-05- Revision W-0. 3.32 M- 3.33 . 3.34 AN-97--97-. 3.35 1137CCISM-R1-00, Revision 0. 3.36 1137CCISM-300-. Latent fiber is assumed to have the same as-fabricated density and hydraulic properties as Nukon per the Safety Evaluation of NEI 04-07 (Ref. 3.5, Page VII-3). It is assumed that even if the filter bag only retains the minimum amount of fiber it is rated for (i.e 97% of all bypass), this amount is still conservatively higher than the retention of the fuel assemblies.
WCN-021-DSPEC-001 This section outlines the parameters that are relevant to the scope of the Wolf Creek large-scale penetration testing. A total of two large-scale penetration tests may be performed. Past large-scale fiber penetration testing has shown that a few parameters (i.e., strainer geometry, perforated plate opening size, approach velocity, water chemistry, and fiber type) have strong effects on fiber penetration (Ref. 3.6, Section 8). Fiber type, water chemistry, and approach velocity are addressed in the following sections, and strainer geometry is addressed in Section 6.1.1.Variable Variable Type Values for Testing Low High Fiber Type Fixed Nukon Water Chemistry Fixed Most conservative value as determined by small-scale tests (See Section 5.2) Approach Velocity (ft/s) Fixed 0.0061 (Section 5.5) Fiber Concentration (lbm/ft3) Fixed 0.01504 0.02748 (Section 5.3) Water Temperature Fixed 120°F (Section 0) Fiber Preparation Fixed All fibrous debris shall be prepared using high-pressure water jets in accordance with the NEI guidance (see Section 6.2.5). Perforate Plate Configuration Fixed The perforated plates of the test strainer shall have the same properties (e.g., opening diameter, arrangement and thickness) as the actual strainer at the plant (Section 6.1.1). Flow Condition Approaching Strainer Fixed Sizing of the test strainer shall ensure flow conditions approaching the test strainer are comparable to the actual strainer (Section 6.1.1). Due to the similarity between the WCGS Nuclear Plant (PBNP), small-scale testing for WCGS will be foregone and the results from PBNP small-scale testing will be used to inform some of the large-scale testing parameters at Wolf Creek. The parameters from PBNP testing that will be used to inform the testing at Wolf Creek include water chemistry, fiber concentration and modifications to mitigate fiber bridging. A comparison of these parameters for PBNP and WCGS is provided in the table below.
WCN-021-DSPEC-001 Strainer Manufacturer PCI PCI 3.25 & Section 1.0 Perforated Plate Hole Diameter 3.25 & Section 2.1.1 Disk Thickness 3.25 & Section 2.1.1 Gap Between Discs (for installed strainers) 3.25 & Section 2.1.1 Buffer Solution NaOH NaOH 3.25 & Section 2.3 Water pH 8.73-9.62 7.0-9.5 3.25 & Section 2.3 Boron Concentration 2117-2406 ppm 2162-3243 ppm 3.25 & Section 2.3 Fiber Concentration 0.01504 0.02748 lbm/ft3 0.001-0.054 lbm/ft3 3.25 & Section 5.3 As shown in Section 2.5, Wolf Creek has the following fibrous debris types: Nukon, Antisweat blankets, Cerablanket, Thermo-Lag fire barrier, Darmatt fire barrier, and latent fiber. Latent fiber will be substituted by Nukon as a result of equivalent density and hydraulic properties (see Section 4.0). Per assumption 4.29 in Reference 3.21, the fibrous portion of Thermo-Lag is assumed to have the same microscopic material properties as Nukon, and will therefore be substituted by Nukon as well. For the bounding fiber breaks provided in Table 2, the fiber mass consists entirely of Nukon, latent fiber (substituted by Nukon), and Thermo-Lag fire barrier (substituted by Nukon). These breaks contain no Antisweat blankets, Cerablanket, or Darmatt fire barrier (Ref. 3.27, Appendix 1). Therefore, Antisweat blankets, Cerablanket, and Darmatt fire barrier will not be included in the large-scale test. Cerablanket is only generated by reactor nozzle breaks, which can only be partial breaks due to plant geometry (Ref. 3.21). The reactor nozzle partial breaks range in size from 4are bounded by the DEGBs presented in Table 2 with regards to total fiber fines transported to the strainer. Calvert Cliffs Nuclear Power Plant (CCNPP) and Arkansas Nuclear One (ANO) conducted small-scale fiber penetration testing which, in part, performed a sensitivity analysis on what impact various fiber type mixtures had on fiber penetration (Ref. 3.35). The sensitivity analysis included WCN-021-DSPEC-001 WCN-021-DSPEC-001 From the results of the CCNPP/ANO small-scale testing, it is concluded that testing with Cerablanket would result in non-conservative bypass results. Therefore Cerablanket will not be included in the large-scale penetration tests for WCGS. In summary, the only fiber type that shall be tested is Nukon. As discussed in Section 1.0, particulate debris shall not be used in penetration testing. Water chemistry utilized in large-scale testing shall be representative of the post-LOCA conditions at Wolf Creek, as described in Section 2.3. The results from small-scale testing at PBNP show that water chemistry with low boron concentrations and high pH is the most conservative for fiber penetration (Ref. 3.26, Page 27). The results from PBNP small-scale testing are valid to inform the WCGS large-scale test because both plants use NaOH as a buffer and the ranges for water pH level and boron concentration are comparable, as shown in Table 4. Fiber concentration is defined as the mass of fibrous debris divided by water volume. The small-scale testing at PBNP indicated that penetration quantity is unaffected by variation in fiber concentration within tested ranges (Ref. 3.26, Page 27). Therefore, fiber concentration will be treated as a fixed parameter to be met within the range specified. As shown in, the fiber concentration range for PBNP bounds both the high and low ends of the range for WCGS, therefore the results from the PBNP small-scale testing are valid to inform the Wolf Creek large-scale testing. Since the debris quantities presented in Section 2.5 are for a single strainer, the fiber concentration in the recirculating water volume is estimated by doubling these values. The minimum fiber concentration is calculated to be 0.00260 lbm/ft3 by dividing the mass of 8.75diameter pipe break (2 x 51.5 lbm, Section 2.5) by the sump pool volume after a LBLOCA at CS switchover (39,626 ft3, Section 2.2). Similarly, the maximum fiber concentration is calculated to be 0.02748 lbm/ft3 by dividing the maximum fine fibrous debris mass (2 x 485.6 lbm, Section 2.5) by the sump pool volume after a small break LOCA (SBLOCA) at ECCS switchover (35,339 ft3, Section 2.2). The intermediate debris concentration is taken to be the average of these two values, 0.01504 lbm/ft3. The debris concentration utilized in large-scale testing shall be chosen by Alden, shall fall between the intermediate and maximum prototypical values provided in this section, and shall be the same for both tests. Since the range of fiber concentrations of WCGS is bounded by the range tested at PBNP, testing with any concentration in the range should not have a statistically significant impact on the penetration results, per the conclusions of the PBNP testing (Ref. 3.26). Therefore a concentration between the intermediate and maximum prototypical values is used for practical purposes.
WCN-021-DSPEC-001 The water temperature to be used during testing shall be fixed at 120°F and shall be maintained consistently within +/-5°F of the prescribed test temperature. The test temperature will not be varied because past PWROG small-scale fiber penetration tests indicated that water temperature does not have a statistically significant impact on fiber penetration quantity (Ref. 3.6, Section 8). Additionally, testing at this temperature is more prototypical than at room temperature and does not present significant safety risks to the testing personnel. Past testing at Alden also has shown that testing at higher temperatures results in less floating fiber. This is due to a decrease in the solubility of air in water as temperature increases. Average approach velocity is calculated by dividing the volumetric flow rate through the sump strainer by the surface area of the strainer. The WCGS strainer is designed such that the average approach velocity for each strainer module or stack is equivalent. As described in Section 2.4, the calculated surface area of the sump strainer assemblies is 3,311.5 ft2 each. PWROG small-scale fiber penetration tests, which tested the sensitivity of fiber bypass to approach velocity, concluded that high velocities yielded more fiber penetration than low velocities (Ref. 3.6, Section 7.2). Therefore the maximum approach velocity is used for large-scale testing at Wolf Creek. The CS flowrate is constant for both one train and two train operation. The single train RHR flowrate (4880 gpm, Ref. 3.34) is 80 gpm higher than the two train RHR flowrate (4800 gpm, Section 2.4), resulting in a higher approach velocity and potentially a higher bypass fraction. However, experience indicates that doubling the surface area will have a greater impact on the penetration quantity than the 2% increase in velocity. Therefore, the two train RHR flowrate was chosen for the penetration testing because two train operation maximizes the strainer surface area, which has a greater effect on the total amount of fiber penetration. The maximum flow rate through each strainer for two train operation is calculated to be 8750 gpm, which will be rounded up to 9100 gpm for testing. This rounding bounds the +1% EDG over frequency (Ref. 3.33, SR 3.8.1.7) which would result in a total maximum flow rate of 8837.5 gpm. Using 9100 gpm as the testing flow rate provides an additional 262.5 gpm of margin beyond the maximum flow rate caused by the 1% EDG over frequency. This margin is adequate to cover the 80 gpm difference between single train and two train operation. The testing flow rate of 9100 gpm yields a maximum approach velocity of 0.0061 ft/s. Equation 1 WCN-021-DSPEC-001 As stated in Section 5.0, a total of two large-scale tests may be performed. The first test should be performed at the maximum approach velocity, with prototypical debris type and concentration. The second test may be used to examine the impacts of changing a test parameter value, or it may be used as a confirmatory test. The need for as well as the input parameters for the second test will be discussed with WCGS before proceeding. The testing shall be designed to quantify the amount of fiber penetration through the strainer and also provide data to analyze fiber penetration as a function of time. In general, it is expected that a given quantity of fibrous debris is batched into a test tank for each test. The debris-laden water shall then be circulated by a pump through the test strainer, a debris filtering system, and other components along the flow loop. Fiber that passes through the test strainer shall then be collected by a debris filtering system, which may include filter bags installed inside filter housings.
Before and after each test, the filter bags shall be weighed, and the weight gain of the filter bags shall be used to quantify the amount of fiber penetration. The results of different test cases shall then be used to determine the total amount of fiber penetration expected in the plant as a function of time. The following subsections contain additional requirements pertaining to test apparatus, test preparation, and test control which shall be incorporated into the Alden test plan. 6.1.1 Test Strainer The test strainer for the large-scale Wolf Creek fiber penetration testing shall be a section of one of the strainer modules, representative of those installed at the plant, which maintains the configuration of the strainer module assembly. When sizing the test strainer, the following requirements must be considered. 1. Approach velocity of the test strainer shall match that of the actual strainer modules at the plant (see Section 5.5). 2. Key dimensions (e.g., opening diameter, thickness) of the perforated plates used for the test strainer shall match those of the actual strainer at the plant. 3. The spacing between external faces of two neighboring disks must be equal to or greater than that of the actual strainer (1" from face to face, see Section 2.1). Increasing the space is allowed only for the purpose of preventing fiber bridging over the gap. 4. The flow conditions approaching the gap between two neighboring disks shall be maintained as closely as possible to that of the actual strainer. A reduction in circumscribed fluid velocity resulting from an increase in the gap width between strainer disks to prevent bridging is acceptable. 5. The frictional head loss for flow inside a disk of the test strainer shall be comparable to that of the actual strainer.
WCN-021-DSPEC-001 Although the test strainer will be modified, the key design parameters of the test strainer shall still match those of the actual strainer installed at the plant. PWROG small-scale testing indicated that strainer geometry impacts the amount of fiber penetration. However, this impact is attributed to differences in the angle of attack of the flow approaching the strainer (Ref. 3.6, Section 7.5). The angle of attack of flow to the modified strainer shall match that of the installed strainer such that it will not impact large-scale penetration testing results. The test strainer shall also be designed such that it can be disassembled and thoroughly cleaned after each test. In addition to the above requirements, the test strainer should be modified in order to mitigate bridging effects from the fibrous debris. This is appropriate because bridging occurs more readily during penetration testing as a result of the absence of particulate, which can serve to break up fibrous bridges. It is recommended that every other strainer disk be removed from the prototypical Wolf Creek strainer module in order to mitigate bridging effects. This modification In the PBNP large-scale bridging (Ref. 3.29, Page 1, 16). It is also recommended that distance between the strainer and the pit wall be increased to a larger than prototypical gapWCGS (Ref. 3.11). The PNBP large-scale testing report shows that, similar to removing disks, this larger than prototypical gap has a conservative impact on penetration results (Ref. 3.29, Page 16). Note that the actual installed strainer at Wolf Creek will not be modified. Instead, the fibrous penetration per unit area results from the test on the modified strainer will be applied to the installed strainer. This technique is conservative because it assumes that the entire surface area of the installed strainer is available for penetration, when in reality some surface area may not be available due to bridging or a low-permeability granular layer of particulate atop the fiber bed (Ref. 3.4, Page 3-67). Having the entire surface area available for penetration is conservative because it maximizes the amount of fiber penetration. Therefore, because the penetration per unit area results from the large-scale penetration test represent a strainer with no bridging and the entire surface area available for penetration, they are conservative and bounding for the installed strainer at Wolf Creek, which likely would not have the entire surface area available for penetration. 6.1.2 Debris Introduction System Debris shall be added to the test tank away from the test strainer. The introduction system shall be designed to minimize splashing, which may result in loss of debris, and to avoid significant effect on the system flow rate.
WCN-021-DSPEC-001 6.1.3 Strainer Suction Piping The piping connecting the test strainer to the filter housings shall be designed to avoid the settling of fibrous debris, and must meet the following requirements (excluding vertically-mounted piping with downward travelling flow, as settlement will not be an issue): 1. Flow velocity greater than 1 ft/s shall be maintained to ensure complete fiber transport. This requirement is based on NEI 04-07 (Ref. 3.4, Page 4-29) which indicates that a t 2. There shall be no sudden and significant flow area expansions or contractions on horizontal pipes along the flow path as these may facilitate fiber settling and accumulation in front of the area of change. 6.1.4 Isokinetic Sampling System Grab samples of the debris laden water downstream of the test strainer shall be taken using an isokinetic sampling system and shall be used to determine live debris concentrations at the time of the sample during post processing. The sampling system should be installed downstream of the test strainer and upstream of the filter housing. For each test, sampling shall be done eight different times, with two samples taken each time. 6.1.5 Fiber Penetration Filtering System Water and fibers that pass through the test strainer shall enter a filtering system which collects the fibers. The filtering system must meet the following requirements: 1. The filtering system shall have at least two parallel filter housings to facilitate filter bag change during the test. 2. The filter bags shall have a retention rating of >97% for the fiber type that has the smallest characteristic size (see Table 1). Per Assumption 4.2, it assumed that even if only 97% of the bypass is retained by the filter, this will still be conservatively higher than the retention of the fuel assemblies at WCGS. 3. At any given time during a test, at least one filter housing (with appropriate filter bags installed) shall be in service to accommodate the full flow of the test system. The filter housing and filter bags shall have appropriate flow rate rating for such use. 6.1.6 Test Loop Pump The pump shall be sized to provide sufficient head to circulate water through the test loop while meeting test specifications. Specifically, the pump shall be capable of maintaining a flow rate such that requirements of Section 6.3.1 are met and the required strainer approach velocity is WCN-021-DSPEC-001 satisfied (see Section 5.5). In order to avoid interference with debris, the pump shall be placed upstream of the debris introduction system and downstream of the filter bags. 6.1.7 Instrumentation The Alden test plan shall specify the accuracy, uncertainty, and measurement range of the instrumentation required. The following parameters shall be measured during the testing. 1. Test strainer head loss 2. Test flow rates 3. Filter housing head loss 4. Test water temperature 5. Test water pH 6. Test water conductivity 7. Weight of filter bags (before and after testing) 8. Weight of test fiber batches 6.1.8 Test Loop Air Entrainment Prior to starting large-scale testing, the test loop shall be water solid with minimal amount of air entrainment. Bubble formation shall be minimized and have little to no effect on fiber debris surrogate transport and settling. It is strongly recommend that the loop (or portions thereof) be pneumatically pressure-tested prior to starting large-scale testing.6.2.1 Test Water As discussed in Section 2.3, the large-scale fiber penetration testing shall use borated and buffered water as the test solution. The test solution shall be prepared using deionized (DI) water which shall have a conductivity less than 5 micro-laboratory reagent water per ASTM Standard D1193 (Ref. 3.7). 6.2.2 Preparation of Test Loop Prior to any testing, thorough shakedown of the test loop shall be performed. The shakedown should include (but not be limited to) the following: 1. Perform leakage tests on all components and connections of the test loop, including all vent valves, dead ends, and isolation valves. 2. Confirm the test loop can perform satisfactorily at the highest test flow rate. 3. Demonstrate appropriate level of mixing inside the test tank to minimize settling of debris and disturbance to the debris bed on the strainer.
WCN-021-DSPEC-001 4. Confirm that the debris introduction system (if required) performs satisfactorily at the highest introduction rate required for the tests. 5. ty to heat up and cool down if required by the test plan. 6. Check instrumentation installation and calibration. 7. function as desired. At the beginning of each test, the test loop shall be thoroughly cleaned. The cleaning may be performed by running the test loop through filter bags, which can be inspected periodically until no residual debris is observed visually. The filter bags used for cleaning shall be discarded. Prior to the test, all instrumentation devices and the data gathering system must be verified to be functioning properly. 6.2.3 Filter Bag Treatment Prior to Test Prior to testing, each of the filter bags shall be uniquely labeled and verified to be free of damage.
The bags shall be dried and weighed to obtain a steady state baseline weight. Care shall be taken to ensure that foreign debris shall not be introduced to the filter bags during this process.
Afterwards, the treated bags shall be properly stored until testing. 6.2.4 Control Filter Bag After preparation of the test loop (Section 6.2.2) has been completed, one filter bag, having met the requirements outlined in Section 6.2.3, shall be installed inside a filter housing as the test pump is run at test conditions for 10 pool turnovers (PTO) without debris addition. Afterward, the bag shall be removed and processed according to Section 6.3.11 and marked CONTROL. This bag will serve as a reference for baseline weight gain. 6.2.5 Debris Preparation Prior to debris processing, Alden shall confirm that the debris materials have been heat treated according to NEI protocol (Ref. 3.1). If the debris materials need to receive heat treatment as part of the debris preparation process, Alden shall submit a heat treatment procedure to ENERCON for review. Appropriate test solution shall be used for debris preparation. Fiber fines shall be prepared per the NEI protocol (Ref. 3.1). During the separation of the test quantity from the bulk quantity of debris (Ref. 3.1, Section 6.6), care shall be taken to prevent the creation of debris shards (i.e., no separated pieces shall have any side with a length less than the thickness of the bulk material from which the piece was cut).
WCN-021-DSPEC-001 The processed fiber shall then be inspected by a knowledgeable technician to ensure that the fine fiber load contains mainly Class 2 fibers per Table B-3 of the NUREG/CR-6224 standard (Ref. 3.3, see Table 6 below). The fiber processed per the above instructions should be easily transportable and readily dispersed in water. Each processed fiber batch shall be photographed on a light table for record-keeping. Class No. Description 1 Very small pieces of fiberglass material, "microscopic" fines which appear to be cylinders of varying L/D. 2 A single flexible strand of fiberglass, essentially acts as a suspended strand. 3 Multiple attached or interwoven strands that exhibit considerable flexibility and which due to random orientations induced by turbulence drag could result in low fall velocities. 6.3.1 Flow Control For all test cases, the flow rate shall be consistently maintained at +5/-0% of the prescribed test flow rate. It is recognized that flow adjustments and filter housing switchover may induce flow variations. Care shall be taken to prevent the variation in flow rate from causing excessive disturbance to the debris bed on the strainer. If the differential pressure across the test strainer or the filter housings becomes larger than the design limit of the test system, the flow rate shall be reduced or the test terminated. The design limits shall be established in the Alden test plan. 6.3.2 Test Solution Temperature For all test cases, the test solution temperature shall be maintained consistently within +/-5°F of the prescribed test temperature. 6.3.3 Test Strainer Submergence The submergence of the test strainer shall be maintained as close to that of the actual strainer as possible (i.e., from to per Section 2.2). Submergence shall be adequate to prevent vortexing, fully submerge the debris bed, and prevent hindrance of debris transport to the strainer. Proposed deviations from the values above by Alden shall require adequate justification WCN-021-DSPEC-001 in the test plan. The fibrous penetration results shall be provided in such a manner that they can be applied on a fibrous penetration per unit area basis. 6.3.4 Test Debris Quantity The test debris loads shall be determined based on the plant loads, provided in Table 7, and the ratio of the test strainer surface area to that of the Wolf Creek strainer. As shown in Table 2, the total fiber quantity related to the 10.5 inch break bounds that of the 11.118 inch (which is the bounding surge line break from a fiber fines perspective) and 11.5 inch breaks. Therefore, the loads related to the 11.118 and 11.5 inch breaks do not need to be tested. Batches of all breaks shall include an additional 10% fiber quantity over the plant loads to provide margin, as provided in Table 7. As described in Section 5.1, only Nukon will be used in large-scale penetration testing for Wolf Creek. Table 7 summarizes the batching requirements that must be met for each of the listed break sizes. The debris quantities listed in Table 7 are cumulative debris quantities. It is expected that batches at intermediate debris loads will be added to the batching requirements in Table 7 in order to eliminate sudden, large fiber load increases. This is acceptable as long as the debris loads below are tested. As described in Section 2.5, only fine debris will be tested, and no small or large pieces will be included. Representative Break Size (in.) Debris Surrogate Size Bounding Fibrous Debris Quantities at the Strainer (lbm) 10% Margin Required over Plant Debris Loads (lbm) Cumulative Total Plant Debris Load to be Tested (Including Margin) (lbm) 10.5/11.118/11.5 Fine 82.9 8.29 91.19 27.5 Fine 325.6 32.56 358.16 29 Fine 470.9 47.09 517.99 31 Fine 485.6 48.56 534.16 6.3.5 Debris Introduction Incremental fiber addition shall be used for the penetration testing since fiber penetration is expected to be higher when the strainer is relatively clean, eventually leveling off as debris accumulates on the strainer. For the same reason, it is expected that the batch sizes will increase gradually throughout the penetration testing. The number and sizes of the debris batches shall be specified in the test plan. If a debris concentration is specified, the introduction process should be timed to ensure the acceptance criterion on the debris concentration is met. 6.3.6 Debris Addition Interval Timing Before introducing additional debris when multiple batches are required for a given break size, a minimum of 5 PTO shall be run after the completion of bulk addition, and it shall be confirmed WCN-021-DSPEC-001 that little to no debris from the previous batch remains suspended in the test tank. For all other additions, the minimum time between additions shall be governed by the Alden test plan. 6.3.7 Filter Bag Change Schedule The filter bag change schedule shall be developed in the Alden test plan. The schedule shall ensure that fiber penetration data obtained from the testing is adequate to evaluate both prompt penetration occurring as fiber arrives at the strainer as well as long-term penetration due to fiber erosion and shedding from the fiber bed formed on the strainer. Long-term fiber penetration shall be evaluated for the last batch of debris, as well as some intermediate batches. The long-term penetration data shall be adequate to accurately extrapolate the penetration results out to 30 days. Per page 6 of Reference 3.8, the suggested duration for which the test loop should run after final debris addition is at least as long as the hot leg switchover time for the plant. For Wolf Creek, the hot leg switchover time after a LOCA is approximately 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> (Ref. 3.1, Page 45). Thus, a minimum duration of 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> after final debris addition is required to gather adequate data to evaluate shedding penetration. 6.3.8 Tank Turbulence Level The turbulence level inside the testing tank shall be maintained high enough to maximize transport of fiber fines to the test strainer. The turbulence level close to the test strainer shall be carefully controlled to avoid disturbances to the debris bed formed on the strainer. Such a level of turbulence shall be maintained throughout each test. 6.3.9 Treatment of Settled Debris If non-representative debris settling is observed during a test, additional agitation should be provided to minimize non-representative settling. Such activities shall be documented in the test log (e.g., when, where and for how long the agitation is performed). No settling of fiber fines in the introduction portion of the test tank is allowed. Agitation must not disturb the debris bed on or around the test strainer. Debris that has settled non-representatively shall be photographed, noted in the test log, and quantified. 6.3.10 Treatment of Floating Debris After adding each batch of debris to the tank, any significant amount of floating debris (>~1 g)shall be collected, mixed in a bucket and re-introduced to the test tank in the same manner as the bulk batch. At least 5 PTOs shall be run after the re-introduction to allow the re-introduced debris to reach the filter. At the end of one test, significant quantities of residual floating debris shall be collected, dried and weighed. The amount of collected floating debris will be deducted from the total debris amount when calculating fiber bypass fraction.
WCN-021-DSPEC-001 6.3.11 Process of Filter Bags after Test The filter bags with collected fibers shall first be rinsed with DI water to remove any residual chemicals. The bags shall then be dried and weighed with the weight gain of each bag taken to be the amount of fiber penetration collected. This test specification provides the inputs and requirements to the Wolf Creek large-scale fiber penetration testing. A test plan and various test procedures will be developed by Alden and approved by ENERCON. The test plan shall include lessons learned from all Alden Condition Reports issued within the last year, and specify their actions to prevent reoccurrence. The test procedures shall provide prescriptive step-by-step instructions and require signed documentation for the execution of each step. ENERCON and WCGS shall have the option to witness the performance of critical steps. A test log shall be created to record key testing activities and observations as required by the test procedure, including, but not limited to, flow adjustments, debris addition (beginning and completion), agitation (including time and duration), filter removal and installation, and all other actions that affect the testing environment. The test logs shall describe the activities in adequate details without recourse to the test engineer. The test log should also include written documentation of the test conditions as a backup to the electronic data acquisition record. A test report shall be prepared to document the test system setup, instrumentation, test conditions and test results. The test results shall include a maximum penetration total for the WCGS strainers and the results shall be extrapolated out to 30 days. The test report shall also include a penetration model that will curve fit time-dependent penetration test data with the amount of fiber accumulated at the strainer. The model will allow for the use of overall fiber penetration for any given debris load in the sump pool bounded by the tests performed. Any deviations from the test specification, test plan and test procedures shall be approved by the Alden test engineer with concurrence from the ENERCON and utility representatives. The testing activities outlined in this document involve the use of various insulation materials, boric acid, and NaOH. All applicable requirements in the Safety Data Sheet (SDS) shall be followed when handling the insulation and other test materials and components.
WCN-021-DSPEC-001 proved Suppliers List. Therefore all testing activities and document preparation shall be performed under meet the requirements of 10 CFR 50, Appendix B and 10 CFR, Part 21.
ZOI Fibrous Debris Preparation: Processing, Storage and HandlingRevision 1 January 2012 Nuclear Energy Institute Page i Revision 1, 1/24/12 Generic Procedure ZOI Fibrous Debris Preparation: Processing, Storage and Handling TABLE OF CONTENTS SECTION PAGE 1. SCOPE ...................................................................................................... 1 2. PURPOSE ................................................................................................. 1 3. DEFINITIONS ............................................................................................ 1 4. REQUIREMENTS ...................................................................................... 1 5. RESPONSIBILITIES .................................................................................. 2 6. PROCESS ................................................................................................. 2 6.1 Safety......................................................................................................... 2 6.2 Initial Procurement and Storage ................................................................ 2 6.3 Aging of Fiber ............................................................................................ 2 6.4 Storage of Aged Fiber ................................................................................ 3 6.5 Soaking of Aged Debris ............................................................................. 3 6.6 Preparation of Aged Debris Fines .............................................................. 3 6.7 Preparation of Aged Debris Smalls ............................................................ 4 6.8 Photographs of Fiber Debris ...................................................................... 5 6.9 Records ..................................................................................................... 5 7. REFERENCES .......................................................................................... 5 APPENDICES Appendix A Safe Handling of Fiber ............................................................................... 6 Appendix B Datasheet for Fiber Preparation ................................................................. 7 Generic Procedure Revision 1, Page 1 ZOI Fibrous Debris Preparation: Processing, Storage and Handling 1. SCOPE This document covers the procedures for processing, storage and handling of the fiber that will be used in sump strainer testing. The resulting fibrous debris from this procedure is intended to represent fibrous material generated as a result of jet impingement within the appropriate zone of influence (ZOI). The overall test program is described in a test plan. This document is intended to outline the procedures to be used by the technical support team to process, store and handle fibrous debris that will be used as part of the test program. The material will be procured externally and processed to meet the requirements before it is used. 2. PURPOSE The purpose of this document is to ensure that the requirements for processing, storage and handling of the fibrous debris that will be used for the XYZ Sump Strainer Test Program will be met, and that any additional requirements relating to processing, storage and handling are also identified. 3. DEFINITIONS oFines - readily suspendable in water (Classes 1 through 3 of Table 3-2 ofNUREG/CR-6808)oSmall pieces - Table 3-2 of NUREG/CR-6808)oLarge pieces - clumps of fibers > 4 inches on a side (Class 7 of Table 3-2 ofNUREG/CR-6808)4. GENERAL REQUIREMENTS The fiber required for the testing is specified in the test plan as to the type of materialto be used for preparation per this document, e.g., Nukon, Mineral Wool, Temp-Mat,etc. The fibers will be processed as fines, small pieces, and large pieces, asdictated by the test plan.
Generic Procedure Revision 1, Page 2 All weight measurements shall be performed using calibrated scales.The weighed debris must be stored and clearly labelled with weight, type, and date.This is done to prevent the possibility of incorrectly identifying the material at thetime of its use. Documentation of the weighed debris shall be per the requirementsof the test plan.The debris must be handled in a safe manner to ensure minimal hazard to personnel. Each relevant material safety data sheet (MSDS) must be read before handling debris and each worker must wear appropriate personal protective equipment (PPE).A data sheet, in a form similar to Attachment B, shall be used to document the completion of the applicable steps of this procedure.5. RESPONSIBILITIES The Scope of Work will be performed in accordance with this document and the test plan developed for the specific client. 6. PROCESS This section identifies the procedures to be used to procure, store, process and handle fibrous debris. Fibrous debris will be heated on a hot plate to simulate the aged insulation in the plant before a loss of coolant accident (LOCA), and processed to achieve the required fiber size distribution. 6.1 Safety Due to its potential negative effect on health and status as an irritant, the fiber material requires appropriate safety precautions when handling. These procedures are outlined in Appendix A. Due care must be used to ensure operator safety. 6.2 Initial Procurement and Storage Fiber materials will be procured from specified manufacturers. The procured materials will be stored in a sheltered location prior to further processing. The fiber will normally be received as rolls or bundles. 6.3 Aging of Fiber NOTE Fiber material that had previously been heat treated, but may not have had full documentation as provided in the following steps may still be used for final debris size preparation provided a visual inspection of the acceptability of the heat treatment (as described below) is performed and documented within the test plan.
Generic Procedure Revision 1, Page 3 The fiber shall be aged by heating one side of the insulation on a hot plate at300C, +/- 38C for 6 to 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. (Previous testing has shown this temperatureand time to be adequate to appropriately age the material.)The specific aging procedure is as follows:
oA batch (sheet) of fiber is placed on the hot plate.oA method is provided to periodically monitor plate temperature.oThe hot plate is energized with the time of starting recorded.oWhen plate temperature reaches the required temperature, the time isrecorded (start of 6 to 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> heating).oAfter time at temperature, the hot plate is deenergized. This time is recorded.oWhen safe to do so, the insulation material is removed from the hot plate and allowed to cool to near ambient conditions.oThe insulation is then inspected to ensure the heat treatment was effective.
Inspection criteria for acceptance is a gradient of color in the fiberglass from the hot face to approximately half way through the thickness of the insulation sheet commensurate with the temperature gradient through the insulationsheet. (Reference 7.b)oThe aged fiber is then weighed and placed into labelled bags that identifiesthe type of fiber, how processed, and the weight.6.4 Storage of Fiber The aged insulation is stored in a sheltered location approved by the testing engineer. Each bag is labelled to identify how the debris was processed, the type of debris, the batch number and the lot number, if available. 6.5 Soaking of Aged Debris (Optional) As specified by the test plan, the aged debris may be soaked to remove the aging produced particulate matter such as unattached binders and combustion products. This is done by soaking the fibrous debris in a container of water for no less than two minutes and then draining the contents through a Tyler 65 mesh screen (or functional equivalent) to remove small particles and excess water. If used, this step should be accomplished just prior to subsequent steps to prepare the fibers for testing. Long term storage of wetted materials in closed containers should be avoided. 6.6 Preparation of Aged Debris Fines NOTE Wetted materials should not be stored for longer than approximately 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to use due to the potential for changes to the properties of the material. NOTE Prior to performance of Step 6.5, if used, the mass of material specified by the test plan shall be obtained as specified in the first two bullets of Step 6.6. Post-soaking weights do not need to be obtained.
Generic Procedure Revision 1, Page 4 The mass of fiber required by the test plan is identified and this quantity is removedfrom the bulk aged material through either mechanical means (shears, knife, orequivalent) or by hand separation.The removed aged fiber is then weighed and recorded.Smaller batches of fiber are then separated from the quantity separated from the bulk quantity by pulling material such that the final volume will result in a fiber to.The smaller batches of fiber are then placed in the bottom of a suitable container(typically a cut off section of a plastic barrel) that has been rinsed clean of othermaterials and contains the required amount of water necessary to maintain thespecified fiber volume to water ratio.Fiber separation is then accomplished by using a high pressure water jet from acommercially available 1500 psi pressure washer with a small diameter fan type tip(recommended), with the nozzle maintained at slightly above or slightly below thewater surface. The time necessary to separate the clumps into individual fibers varies, but is generally accomplished within about 2 to 4 minutes.The degree of fiber separation is confirmed, by visual inspection, to meet expectations and consistency with previous batches, including meeting the definitionof fines provided previously.Several batches, prepared as described above for subsequent introduction and usein testing, are then mixed together to create the quantity needed for testing. Thebatches that are mixed should be combined such that the combined mixture resultsin a fiber mass to volume of water ratio less than or equal to approximately 0.21 lbs/gal (25 gm/l). The combined materials are then agitated through use of the pressure washer previously described or with other mechanical agitation (paddle or paint stirrer) prior to addition to the test loop. The test plan shall contain thenecessary step to verify that minimal agglomeration of the fibers has occurred at the time of addition to the test loop.6.7 Preparation of Aged Debris Small and Large Pieces NOTE oPrecautions should be taken during the following step to minimize direct impingement of the water jet on the fibers. oThe quantity of water required for the following step is not as important as the ability to verify that the fibers are separated and readily suspendable in the resulting solution. NOTE Wetted materials should not be stored for longer than approximately 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to use due to the potential for changes to the properties of the material.
Generic Procedure Revision 1, Page 5 The mass of fiber (small or large pieces) for each specific addition is measured andsoaked in a sufficient quantity of water in a suitable container, or as specified by thetest plan.The mixture is then stirred with a hand paddle until the pieces are fully saturated andseparated from one another (usually 30 seconds to one minute).The degree of fiber clumps separation is confirmed to meet expectations andconsistency with previous batches, including meeting the definition of small or large pieces previously provided.6.8 Photographs of Fibrous Debris Prior to the fiber addition, photographs of prepared fiber may be taken to confirm that the desired size distribution is acceptable. 6.9 Records The test plan shall specify the methods to be used for documenting the debris preparation information generated as a result of this document. For fibrous debris preparation, the Datasheet shown in Appendix B is an example of the type of documentation that can be used. The Datasheet records key information such as material processing date(s), reference purchase order number, mass, instruments used, etc. 7. REFERENCES a.Revised Guidance for Review of Final Licensee Responses to Generic Letter2004-02, "Potential Impact of Debris Blockage On Emergency RecirculationDuring Design Basis Accidents at Pressurized-Water Reactors", March 28, 2008(ML080230234)b.NUREG/CR-6808, "Knowledge Base for the Effect of Debris on PressurizedWater Reactor Core Cooling Sump Performance," February 2003 Generic Procedure Revision 1, Page 6 Appendix A Safe Handling of Fibrous Materials Fibrous materials can cause irritation due to contact (see MSDS before handling). In addition, some of the fibers or fiber products produced can be inhaled or ingested which represents a personnel risk unless necessary precautions are taken. Personnel handling this material should wear appropriate PPE, including an appropriate air filtration mask, safety glasses, gloves and long-sleeved clothing to prevent skin irritation. If necessary, a shower should be taken after handling to remove fibers. Care should be taken during processing and handling to minimize airborne fibers.
Generic Procedure Revision 1, Page 7 Appendix B Example Datasheet for Fibrous Material Preparation Test Number Test Date Mass of Nukon Required (g or lbs) Mass of Mineral Wool Required (g or lbs) Mass of Temp-Mat Required (g or lbs) Mass of XXX Fiber Required (g or lbs) Weigh Scale Instrument Number Aged Fiber Batch # Separation Method Operator WCN-021-DSPEC-001
YESNO N/A GENERAL REQUIREMENTS 1. If the Design Specification is being performed to a client procedure, is the procedure being used the latest revision? 1 2. Are the proper forms being used and are they the latest revision? 1 3. Have the appropriate client review forms/checklists been completed? 1 4. Are all pages properly identified with a Design Specification number, Design Specification revision and page number consistent with the requirements of the procedure? 1 5. Is all information legible and reproducible? 1 6. Is the Design Specification presented in a logical and orderly manner? 1 7. Is it possible to alter an existing Design Specification instead of preparing a new Design Specification for this situation? 8. If an existing Design Specification is being used for design inputs, are the key design inputs, assumptions and engineering judgments used in that Design Specification valid and do they apply to the Design Specification revision being performed? 1 9. Is the format of the Design Specification consistent with client procedures and expectations? 1 10. Were design input/output documents properly updated or identified for update, to reference this Design Specification? 1 11. Can the Design Specification logic, methodology and presentation be properly understood without referring back to the originator for clarification? 1 PURPOSE 12. Does the Design Specification provide a clear and concise statement of purpose? 1 13. Does the Design Specification provide a clear statement of quality classification? 1 14. Is the reason for development and the end use of the Design Specification stated? 1 15. Does the Design Specification provide the basis for information found in the 16. If so, is this documented in the Design Specification? 17. Does the Design Specification provide the basis for information found in the 18. If so, is this documented in the Design Specification? 19. Does the Design Specification otherwise support information found in the 20. If so, is this documented in the Design Specification? 21. Has the appropriate design or license basis documentation been revised, or are the change notice or change request documents being prepared for submittal? 1 22. Are design inputs clearly identified? 1 WCN-021-DSPEC-001
YESNO N/A 23. Are design inputs retrievable? 1 24. If not, have they been added as attachments? 1 25. If Attachments are used as design inputs or assumptions are the Attachments traceable and verifiable? 1 26. Are design inputs clearly distinguished from assumptions? 1 27. Are input sources (including industry codes and standards) appropriately selected? 1 28. Are input sources (including industry codes and standards) consistent with the quality classification and objective of the Design Specification? 1 29. Are input sources (including industry codes and standards) consistent with the 1 30. Are input values reasonable and correctly applied? 1 31. Are design input sources approved? 1 32. Does the Design Specification reference the latest revision of the design input sources? 1 33. Were all applicable plant operating modes considered? 1 ASSUMPTIONS 34. Are assumptions reasonable/appropriate to the objective? 1 35. Is adequate justification/basis for all assumptions provided? 1 36. Are any engineering judgments used? 37. Are engineering judgments clearly identified as such? 1 38. If engineering judgments are utilized as design inputs, are they reasonable and can they be quantified or substantiated by reference to site or industry standards, engineering principles, physical laws or other appropriate criteria? 1 Note: 1. Provide justification for answers to these questions and provide clarification of answers where needed. Question Justification or Clarification Design Specification Originator: Name Date WCN-021-DSPEC-001
Safety-Related Non-Safety-Related Document Verified: Rev. 0 Design Verification Number1: N/A Rev1. N/A Design Verification Method and Scope: Design inputs will be verified by comparing the documented input with the source references and checking the validity of the reference for the intended use. All source references are in the list of references and are referenced specifically where they are used. All assumptions will be evaluated and verified to determine if they are based on sound engineering principles and practices. The methodology, results, and conclusions will be verified. Design Verification Summary: After review of the Large-Scale Fibrous Debris Penetration Test Specification for Wolf Creek Nuclear Operating Corporation and its referenced documents, I have come to the following conclusions: 1. The methodology, design inputs, and approach are appropriate for the specification. 2. The assumptions, test parameters, and technical requirements are reasonably based on verified source references and design inputs. 3. The assumptions, test parameters, and technical requirements have been independently verified. The document content is clear and concise. Based on the above summary, the design document is determined to be acceptable. (Print Name and Sign) Design Verifier: John Chiulli Date: Approver2: Kip Walker Date: Note 1: This field only applies to Design Verifications requiring a unique identifier number. Otherwise, mark as N/A.
WCN-021-DSPEC-001
Document Verified: WCN-021-DSPEC-001 Rev. 0 Design Verification Number1: N/A Rev1. N/A Item CHECKLIST ITEMS Yes No 2 N/A 1 Design Inputs Were the design inputs correctly selected, referenced (latest revision), consistent with the design basis and incorporated in the Design Document? 2 Assumptions Were the assumptions reasonable and adequately described, justified and/or verified, and documented? 3 Quality Assurance Were the appropriate QA classification and requirements assigned to the Design Document? 4 Codes, Standards, and Regulatory Requirements Were the applicable codes, standards and regulatory requirements, including issue and addenda, properly identified and their requirements satisfied? 5 Construction and Operating Experience Have applicable construction and operating experience been considered? 6 Interfaces Have the design interface requirements been satisfied, including interactions with other Design Documents? 7 Methods Was the Design Document methodology appropriate and properly applied to satisfy the Design Document objective? 8 Design Outputs Was the conclusion of the Design Document clearly stated, did it correspond directly with the objectives and are the results reasonable compared to the inputs? 9 Acceptance Criteria Are the acceptance criteria incorporated in the Design Document sufficient to allow verification that the design requirements have been satisfactorily accomplished? 10 Computer Software If a computer program or software is used, have the requirements of CSP 3.03 for calculations or the applicable process CSP and CSP 3.09 been met? 11 Open Assumptions Is the Design Document free of open assumptions or preliminary information that shall be confirmed at a later date? 12 Lessons Learned Have problems with this design known from prior application been considered and resolved? COMMENTS: (Print Name and Sign) Design Verifier: John Chiulli Date: Note 1: This field only applies to Design Verifications requiring a unique identifier number.