DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Status of Claims
A reply was filed on 04/27/2026. The amendments to the claims have been entered. Claims 1, 3-12, 14, 16, and 18-21 are pending in the application with claims 5-6, 8-12, and 18-20 withdrawn1. Claims 1, 3-4, 7, 14, 16, and 21 are examined herein.
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim Rejections - 35 USC § 103
Claims 1, 3-4, 7, 14, 16, and 21 are rejected under 35 U.S.C. 103 as being unpatentable over “Experimental Study of New Generation WWER-1000 Fuel Assemblies at JSC NCCP” (“Enin”) in view of “Study on the Spacer Grid Dynamic Crush Strength According to Cell Sizes” (“Ryu”) and “Development and Demonstration of a New Testing Capability for Simulating Multiple Fuel Assembly Impact During a Seismic Event” (“Zhao”).
Regarding claim 1, Enin (previously cited) (see FIG. 6; see also figure in Table 3) discloses a method of testing nuclear fuel assembly test spacer grids, the test method comprising:
providing a test assembly (“dummy model”) modeling a section of a nuclear fuel assembly, the test assembly comprising a bundle of test rods (“fuel rod”, “FR”) and three test spacer grids (“spacer grid”, “SG”) distributed along the test rods (p. 221: “Dummy models of skeletons and FR bundles containing three spacer grids each were fabricated ... and tested”),
wherein the test assembly comprises exactly three test spacer grids (p. 221: “Dummy models of skeletons and FR bundles containing three spacer grids each were fabricated ... and tested”), and
wherein the test assembly excludes a bottom nozzle and a top nozzle.
Enin discloses testing the test spacer grids by applying a force to a centrally located test spacer grid (“middle SG”) of the three test spacer grids to determine mechanical characteristics and performance of the test assembly structures (p. 217: “Substantiation of design element strength and rigidity”, “This made if possible to conduct the comparison experiments and determine the required mechanical characteristics of different design modifications with small expenses”; p. 221: “The cage design makes it possible to apply a transverse force to the middle SG of dummy model”, “Skeleton and FR bundle rigidity was determined by means of bend test”), but does not appear to explicitly disclose performing an impact test on the centrally located test spacer grid as recited in claim 1.
Ryu (previously cited) (see FIG. 4) is similarly directed towards a method of testing a nuclear fuel assembly test spacer grid (“test grid”, “specimen”) comprising a bundle of test rods (“fuel rod cladding”, “guide tubes”) (Abstract, p. 2: “Short fuel rod cladding and guide tubes are inserted in each cell of the test grid”). Ryu teaches the method comprises:
generating an impact on the test spacer grid (p. 2: “During the test, the spacer grid is impacted by the pendulum hammer”);
measuring and recording at least one impact parameter and/or at least one displacement of the test spacer grid (FIG. 5, p. 2: “The dynamic crush strength in each group was determined at the maximum impact load before buckling”),
wherein the test assembly includes a stationary support (“load cell”, “back plate”), the test spacer grid being pressed against the stationary support during the generating of the impact on the test spacer grid; and
prior to generating the impact, bringing the spacer grid into abutment with the stationary support.
Ryu further teaches the pendulum impact test provides the advantage of verifying seismic performance and mechanical integrity of the spacer grid by investigating the dynamic crush behavior of the spacer grid (Abstract, p. 1: “it is necessary to study the crush strength variations according to the cell sizes in order to verify the seismic performance and mechanical integrity of the fuel. And it can be improved to enhance grid buckling and maintain higher strength throughout the operating life time through structural design of the mid grid”). It would have therefore been obvious to a person having ordinary skill in the art before the effective filing date (“POSA”) to include Ryu’s impact testing in Enin’s method for the predictable advantage of investigating the dynamic characteristics of the spacer grid, as suggested by Ryu.
The modified Enin does not appear to teach the test assembly includes three of the stationary supports (e.g., Ryu’s “load cell”, “back plate”) as recited in claim 1.
However, as discussed above, Enin discloses the test assembly comprises three spacer grids (FIG. 6, Table 3). It was known in the art to provide a stationary support for each spacer grid of a test assembly for a pendulum impact test. For example, Zhao (previously cited) (see FIGS. 2-3, 6) is also directed towards a method of conducting a pendulum impact test on a test assembly (“fuel assembly”, “FA”) comprising a bundle of test rods (“fuel rod”) and test spacer grids (“spacer grid”, “grid”) distributed along the test rods, the impact test comprising generating an impact on a centrally located test spacer grid (“Grid 5”) of the test spacer grids (Abstract, p. 2: “a series of impact tests of spacer grids were performed”; p. 3: “a prototype fuel assembly was tested using selected pendulum parameters”). Zhao teaches the test assembly includes stationary supports, each of the test spacer grids being pressed against a respective one of the stationary supports during the generating of the impact on the centrally located test spacer grid such that the impact on the centrally located test spacer grid is taken up in part by the centrally located test spacer grid and in part by the other test spacer grids (FIGS. 8-10, p. 3: “It can be seen that the impact loads on the two sides of the grid were close to each other”). Zhao further teaches providing each of the test spacer grids with a respective stationary support provides the advantages of measuring and recording impact parameters of multiple test spacer grids of the test assembly, allowing for the investigation of the mechanical characteristics of multiple test spacer grids (FIGS. 8-10, p. 4: “a comparison of the impact forces at various spacer grid locations for pendulum at Grid 5 elevation”, “It shows impact loads at various grid locations and Grid 5 deformation as a function of time. It can be seen that impacts at different spacer grids occur at different time instances”). It would have therefore been obvious to a POSA to include a stationary support for each of the modified Enin’s three test spacer grids for the predictable purpose of examining the characteristics and performance of each of the test spacer grids, as suggested by Zhao.
Regarding claim 3, Enin in view of Ryu and Zhao teaches the testing method according to claim 1. Ryu teaches the generating of the impact is generating a two-side impact that includes impacting the centrally located test spacer grid with an impact member (“hammer”) on a side of the centrally located test spacer grid opposite the stationary support against which the centrally located test spacer grid is applied (FIG. 4, p. 2: “the spacer grid is impacted by the pendulum hammer”). Therefore, Enin’s method, modified to include Ryu’s impact testing and additional stationary supports as taught by Zhao, would have resulted in the features of claim 3.
Regarding claim 4, Enin in view of Ryu and Zhao teaches the testing method according to claim 3. Ryu teaches the impact member is movably mounted by a pendulum to project the impact member against the centrally located test spacer grid (FIG. 4, p. 2: “pendulum impact test equipment”). Therefore, Enin’s method, modified to include Ryu’s impact testing and additional stationary supports as taught by Zhao, would have resulted in the features of claim 4.
Regarding claim 7, Enin in view of Ryu and Zhao teaches the testing method according to claim 1. Ryu teaches heating the test assembly prior to and/or during the generating the impact on the centrally located test spacer grid (p. 2: “The temperature for this test is chosen as operating temperature”, “Three groups of specimens were tested at 600°F temperature”). Therefore, Enin’s method, modified to include Ryu’s impact testing and additional stationary supports as taught by Zhao, would have resulted in the features of claim 7.
Regarding claim 14, Enin in view of Ryu and Zhao teaches the testing method according to claim 1. Enin discloses the test spacer grids each define a plurality of rod cells, each of the rod cells receiving one of the test rods such that each of the test rods passes through one of the rod cells of each test spacer grid (FIG. 6; see also figure in Table 3).
Regarding claim 16, Enin in view of Ryu and Zhao teaches the testing method according to claim 1. Ryu teaches the generating of the impact on the centrally located test spacer grid includes compressing the centrally located test spacer grid between the impact member and the one of the three stationary supports against which the centrally located test spacer grid is pressed against (FIG. 4). Therefore, Enin’s method, modified to include Ryu’s impact testing and additional stationary supports as taught by Zhao, would have resulted in the features of claim 16.
Regarding claim 21, Enin in view of Ryu and Zhao teaches the testing method according to claim 1. Ryu teaches heating the test assembly with a heating device (“furnace”) during the generating of the impact on the centrally located test spacer grid (FIG. 4, p. 2: “The temperature for this test is chosen as operating temperature”, “Three groups of specimens were tested at 600°F temperature”),
the heating device including a heating enclosure (FIG. 4),
the test assembly being disposed within the heating enclosure during the generating of the impact on the centrally located test spacer grid of the three test spacer grids (FIG. 4),
the heating enclosure including a passageway opening (“door”) through which an impact member generating the impact passes to generate the impact on the centrally located test spacer grid (FIG. 4).
Therefore, Enin’s method, modified to include Ryu’s impact testing and additional stationary supports as taught by Zhao, as discussed above with regards to claim 1, would have resulted in the features of claim 21.
Response to Arguments
Applicant argues “Enin teaches push/pull testing which is fundamentally different from the claimed method step of generating an impact” (emphasis in original) (Remarks, p. 7) and “Ryu teaches testing single grids in isolation, not a test assembly with three test spacer grids as claimed” (emphasis in original) (Remarks, p. 7). One cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). Enin discloses testing a test assembly having three test spacer grids to determine mechanical characteristics and performance of the structures of the test assembly (FIG. 6, pp. 217, 221); Ryu establishes that the mechanical characteristics and performance of test spacer grid, such as seismic performance and mechanical integrity, may be determined by generating an impact on the test spacer grid (Abstract, p. 1); Zhao further establishes that providing a stationary support for each of the test spacer grids in a test assembly allows for the investigation of the mechanical characteristics of multiple test spacer grids (FIGS. 8-10, p. 4). Accordingly, the combination of Enin’s method with the impact testing as taught by Ryu and the additional stationary supports as taught by Zhao results in a method of testing a test assembly having three test spacer grids comprising a step of generating an impact as recited in claim 1.
Applicant further argues “[t]here is no motivation in Enin to perform impact testing” (Remarks, p. 7). However, obviousness may be established by combining or modifying the teachings of the prior art to produce the claimed invention where there is some teaching, suggestion, or motivation to do so found either in the references themselves or in the knowledge generally available to one of ordinary skill in the art. See In re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988), In re Jones, 958 F.2d 347, 21 USPQ2d 1941 (Fed. Cir. 1992), and KSR International Co. v. Teleflex, Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007). In this case, the rejection states that Ryu supplies the required motivation: “Ryu further teaches the pendulum impact test provides the advantage of verifying seismic performance and mechanical integrity of the spacer grid by investigating the dynamic crush behavior of the spacer grid (Abstract, p. 1: “it is necessary to study the crush strength variations according to the cell sizes in order to verify the seismic performance and mechanical integrity of the fuel. And it can be improved to enhance grid buckling and maintain higher strength throughout the operating life time through structural design of the mid grid”). It would have therefore been obvious to a []POSA[] to include Ryu’s impact testing in Enin’s method for the predictable advantage of investigating the dynamic characteristics of the spacer grid, as suggested by Ryu” (see Non-Final Rejection dated 01/27/2026, p. 5; see also above rejections).
Applicant further argues “[t]he method of Zhao is thus incompatible with the claimed method which recites that the test assembly excludes a bottom nozzle and a top nozzle” because “Zhao teaches a testing method requiring complete fuel assemblies with nozzles and controlled gaps” (emphasis in original) (Remarks, pp. 7-8). However, the feature of a test assembly excluding a bottom nozzle and a top nozzle is disclosed by Enin (see FIG. 6). As discussed above, Zhao is used to teach providing a stationary support for each test spacer grid. Zhao teaches that this provides the advantages of measuring and recording impact parameters of multiple test spacer grids of the test assembly, allowing for the investigation of the mechanical characteristics of multiple test spacer grids (FIGS. 8-10, p. 4). There is nothing in Zhao to suggest that providing additional stationary supports for a test assembly comprising three test spacer grids and excluding nozzles would not produce useful results. The skilled artisan would have recognized that Zhao’s supplied motivation for providing additional stationary supports (i.e., measuring and evaluating mechanical characteristics of multiple test spacer grids) would be realized regardless of whether the test assembly includes or excludes a bottom nozzle and a top nozzle.
Applicant further argues “Zhao’s testing methodology requires controlled gaps or pre-displacement before impact in both single and multiple assembly tests” (Remarks, p. 8). However, the feature of “bringing the centrally located test spacer grid into abutment with the respective one of the three stationary supports” is taught by Ryu (FIG. 4). As discussed above, Zhao is used to teach providing a stationary support for each test spacer grid.
Applicant further argues “Enin and Ryu also teach away from the method of Zhao. Enin’s simplified three-grid model without nozzles cannot provide the fuel assembly’s dynamic properties ... that Zhao identifies as essential. Ryu’s single-grid approach contradicts both Enin’s multi-grid assembly and Zhao’s complete fuel assembly requirements” (Remarks, p. 8). A prior art reference “teaches away” from a combination if the proposed modification would render the prior art invention being modified unsatisfactory for its intended purpose. Thus, the pertinent question is whether modifying Enin’s method to include impact testing, as taught by Ryu, and to include additional stationary supports, as taught by Zhao, would render the Enin’s method unsatisfactory for its intended purpose. There is nothing to suggest that such a modification would have resulted in an inoperable method or a change to the principle of operation of Enin. The intended purpose of Enin’s method is to analyze and evaluate fuel assembly designs by conducting experiments on test assemblies to determine mechanical characteristics and performance (p. 217: “But the analysis of [fuel assembly] and reactor core design strength and thermomechanical properties is rather sophisticated task that’s why at the beginning of experimental study of FA thermomechnical [sic] stability was established.... The program was aimed at the following: • More precise specification of design; • Verification of design models and codes; • Substantiation of design element strength and rigidity; • Substantiation of FA serviceability during [fuel rod] bundle-skeleton interaction. For tests the assembly fragments and small dummy models of FA skeletons and FR bundles were used. This made it possible to conduct the comparison experiments and determine the required mechanical characteristics of different design modifications with small expense”). There is no rational, technical reasoning that performing impact testing, as taught by Ryu, and including additional stationary supports, as taught by Zhao, would destroy this feature of Enin’s method. Moreover, there is no portion of Enin that would prevent a skilled artisan from performing impact testing, as taught by Ryu, and/or including additional stationary supports, as taught by Zhao.
Applicant’s argument that Examiner has applied hindsight reasoning (Remarks, p. 8) is unpersuasive. It must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the Applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971). Obviousness may be established by combining or modifying the teachings of the prior art to produce the claimed invention where there is some teaching, suggestion, or motivation to do so found either in the references themselves or in the knowledge generally available to one of ordinary skill in the art. See In re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988), In re Jones, 958 F.2d 347, 21 USPQ2d 1941 (Fed. Cir. 1992), and KSR International Co. v. Teleflex, Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007). In this case, as discussed above, Ryu teaches the pendulum impact test provides the advantage of verifying seismic performance and mechanical integrity of the spacer grid by investigating the dynamic crush behavior of the spacer grid (Abstract, p. 1: “it is necessary to study the crush strength variations according to the cell sizes in order to verify the seismic performance and mechanical integrity of the fuel. And it can be improved to enhance grid buckling and maintain higher strength throughout the operating life time through structural design of the mid grid”) and Zhao teaches providing each of the test spacer grids with a respective stationary support provides the advantages of measuring and recording impact parameters of multiple test spacer grids of the test assembly, allowing for the investigation of the mechanical characteristics of multiple test spacer grids (FIGS. 8-10, p. 4: “a comparison of the impact forces at various spacer grid locations for pendulum at Grid 5 elevation”, “It shows impact loads at various grid locations and Grid 5 deformation as a function of time. It can be seen that impacts at different spacer grids occur at different time instances”). Thus, Ryu supplies the required motivation for including impact testing in Enin’s method (i.e., investigating dynamic characteristics of spacer grids) and Zhao supplies the required motivation for including additional stationary supports in Enin’s method (i.e., examining the characteristics and performance of multiple test spacer grids).
Conclusion
THIS ACTION IS MADE FINAL. Prosecution on the merits is closed. See MPEP 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any extension fee pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the date of this final action.
RCE Eligibility
Since prosecution is closed, this application is now eligible for a request for continued examination (RCE) under 37 CFR 1.114. Filing an RCE helps to ensure entry of an amendment to the claims, specification, and/or drawings.
Interview Information
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, Applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
Contact Information
Examiner Jinney Kil can be reached at (571) 270-5217, on Monday-Thursday from 8:30AM-6:30PM ET. Supervisor Jack Keith (SPE) can be reached at (571) 272-6878.
/JINNEY KIL/Examiner, Art Unit 3646
1 Examiner notes, claims 6 and 20 were previously withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected species (Species A3), there being no allowable generic or linking claim (see Final Rejection dated 01/30/2024). Election was made without traverse in the reply filed on 06/16/2023.
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