DETAILED ACTION
Response to Amendment
A Reply was filed 22 April 2026. All amendments to the claims have been entered. Note MPEP 714 II(A) and 37 C.F.R. 1.121(h) for how to file proper amendments to the Abstract and Title.
Claims 1-23 are pending. Claims 12-20 are withdrawn. Thus, claims 1-11 and 21-23 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 § 112(b)
Claim 23 is rejected under 35 U.S.C. 112(b) as being indefinite for failing to particularly point out and distinctly claim the subject matter which an inventor regards as the invention.
The phrase “the first layer . . . is configured to . . . withstand nuclear radiation exposure” is unclear. It is unclear how any material in a reactor core area can withstand nuclear radiation exposure. It is unclear what is meant by the term “withstand”.
Claim Rejections - 35 USC § 103
Claims 1-2, 4, 7, 10, and 21-23 are rejected under 35 U.S.C. 103 as being unpatentable over either of Janakiev (US4192718) or Yokoyama (US20100177859), and further in combination with Livsey (US3470066), Kim (US20160260509), Tian ("Research for the heat leakage caused by gaps on barrel insulation structure of reactor pressure vessel", International Journal of Advanced Nuclear Reactor Design and Technology 1 (2019): 30-42), Antrag (DE2504123A1), Jang ("The effects of the stainless steel cladding in pressurized thermal shock evaluation", Nuclear engineering and design 226, no. 2 (2003): 127-140), and NRC (NRC Bulletin 2002-01: Reactor Pressure Vessel Head Degradation and Reactor Coolant Pressure Boundary Integrity, March 2002).
Claims 1-2
It is well known in the art to have a pressure vessel wall formed of a set of structural layers arranged in a column. For example, Janakiev discloses a steel pressure vessel wall formed of a set of structural layers (1) arranged in a column. Likewise, Yokoyama discloses a steel pressure vessel wall (1) formed of a set of structural layers (6) arranged in a column.
It is well known in the art to have a heat exchanger arranged within a pressure vessel wall. For example, Livsey discloses a heat exchanger (23-25) arranged within a wall (11) of a pressure vessel (10).
It is well known in the art to have a heat exchanger in a pressure vessel, including having the heat exchanger arranged above the core, below the core, or beside the core. For example, Kim discloses a heat exchanger (13) and a pump (100) arranged above the core (12). Kim also discloses [0051] the conventional features of: a primary working fluid circuit; primary working fluid; and a secondary working fluid circulating between a secondary working fluid circuit and an external power generator.
A heat exchanger and pump locations amount to certain design characteristics obviously more favorable to use of a certain locations in light of the specific nuclear reactor design. It is within the skill of the artisan to locate the heat exchanger and pump above the core to meet a particular reactor design.
Modification of each of Janakiev and Yokoyama to have included a heat exchanger and pump in the pressure vessel wall (as suggested by Livsey), where the heat exchanger and pump is arranged above the core (as suggested by Kim), to meet a particular reactor design, would have been obvious to one of ordinary skill in the art.
It is also well known in the art to have an exterior liner on an exterior surface of a wall of a pressure vessel. For example, Tian discloses an exterior liner (e.g., metal reflective cover) on an exterior of a wall of a pressure vessel (e.g., page 30, col. 1; Figure 1). It is well known in the art that liners enhance pressure vessel protection and overall safety. Modification of each of Janakiev and Yokoyama to have conventionally employed an exterior liner, as suggested by Tian, to enhance safety, would have been obvious to one of ordinary skill in the art.
It is well known in the art to have a liner arranged on an inner wall of a steel pressure vessel. For example, Antrag discloses an inner liner (2) on a pressure vessel (1). It is well known in the art that liners enhance pressure vessel protection and overall safety. It is also well known in the art to have pressure vessel walls made of carbon steel, and the inner liner made of stainless steel, to enhance strength. For example, note Jang at page 128, lines 4-9. It is further well known in the art (e.g., Jang) that carbon steel and stainless steel have different coefficients of thermal expansion, such that stainless steel will expand at a higher rate than carbon steel. It is additionally well known in the art that a heated stainless steel liner will expand in the vertical direction (i.e., to a second vertical height). For example, note NRC at page 4.
Modification of each of Janakiev and Yokoyama to have conventionally employed an inner liner, as suggested by Antrag, to enhance safety, would have been obvious to one of ordinary skill in the art. Further modification of each of Janakiev and Yokoyama to have conventionally employed the pressure vessel walls of carbon steel, and the inner liner of stainless steel, as suggested by Jang, to enhance strength, would have been obvious to one of ordinary skill in the art. The skilled artisan would understand (via NRC) that the stainless steel liner in the modified primary references, because of its coefficient of thermal expansion, will expand in the vertical direction from a first (cold) vertical height to a second (hot) vertical height.
As shown, all recited features are well known in the art. The combination of these features would do no more than yield predictable results. That is, the result of the modifications would have been predictable to the skilled artisan. “The combination of familiar elements according to known methods is likely to be obvious when it does no more than yield predictable results." KSR Int'l Co. v. Teleflex Inc., 127 S.Ct. 1727, 1739 (2007).
It is noted that Applicant discloses using a pressure vessel with walls of carbon steel and an inner liner of stainless steel. For example, note Applicant’s published application at [0060]. As shown above, these features are conventional and are obvious to one of ordinary skill in the art. Thus, not only are the rejected claims obvious to the skilled artisan, but also Applicant’s disclosure regarding these features.
Claim 4
Janakiev has interstitial layers (e.g., seals 14) between structural layers (1) arranged in the column.
Claims 7 and 23
It would have been obvious to one of ordinary skill in the art to equip each of Janakiev and Yokoyama with double liners to enhance lining integrity and increase pressure vessel safety. The double liners constitute layers. Although a reference may not disclose a plurality of items, mere duplication of parts has no patentable significance unless a new and unexpected result is produced. In re Harza, 274 F.2d 669, 124 USPQ 378 (CCPA 1960).
It would have been obvious to one of ordinary skill in the art to seal the interior liner to the pressure vessel wall in each of Janakiev and Yokoyama to strengthen liner attachment and to remove any unwanted air gaps between the liner and the wall.
Claim 10
One of ordinary skill in the art would realize that a pressure vessel wall can be implemented with various geometries and dimensions, necessarily amounting to certain design characteristics obviously more favorable to use of certain geometries and dimensions in light of the specific nuclear reactor design. Thus, it would have been obvious to one of ordinary skill in the art to have further modified each of Janakiev and Yokoyama with a uniform diameter between ten and fifteen feet, layer height between one and five inches, and column height over thirty feet, to meet a particular design. The result of the modification would have been predictable to the skilled artisan.
Claim 21
It is well known in the art that heated steel will expand.
Claim 22
It is within the skill of the artisan to provide liners where needed to enhance corrosion prevention. Thus, it would have been obvious to one of ordinary skill in the art to line interior surfaces of the wall facing the set of infrastructure receptacles.
Claims 3 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over either of Janakiev or Yokoyama, and in combination with Livsey, Kim, Tian, Antrag, Jang, and NRC as applied to claim 1 above, and further in view of Jungmann (US3985614).
Jungmann shows that it is well known in the art to employ airflow slots (14) in a vessel wall to provide cooling. It would have been obvious to one of ordinary skill in the art to have further modified each of Janakiev and Yokoyama with airflow slots in the wall to enhance cooling, as suggested by Jungmann.
With regard to claim 3, it is noted that no horizontal structure is required to be between subsets. As a result, a reactor section, equipment section, and condensation section can be different vertical layers in one large open interior space.
Claims 5 is rejected under 35 U.S.C. 103 as being unpatentable over either of Janakiev or Yokoyama, and in combination with Livsey, Kim, Tian, Antrag, Jang, and NRC as applied to claim 1 above, and further in view of either Jones (US3846795) or Faugeras (US3996099).
Each of Janakiev and Yokoyama is capable of being used with different heat exchange fluids. It is well known in the art to employ heat exchange between a water working fluid and a fluidic salt working fluid. For example, note Jones at col. 1, lines 26-30. Note Faugeras at the abstract. Further modification of each of Janakiev and Yokoyama to have employed a primary working fluid comprising water and a secondary working fluid comprising salt, as suggested by either of Jones or Faugeras, would have been obvious to one of ordinary skill in the art.
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over either of Janakiev or Yokoyama, and in combination with Livsey, Kim, Tian, Antrag, Jang, and NRC as applied to claim 1 above, and further in view of NuScale (NuScale Power, “Use of Austenitic Stainless Steel for NPM Lower Reactor Pressure Vessel”, TR-130721-NP, Revision 0, December 2022).
It is well known in the art to employ pressure vessels of different materials. NuScale shows that it is well known in the art to employ a pressure vessel of stainless steel. Substitution of one pressure vessels material for another substantially equivalent pressure vessels material is within the skill of the artisan. Thus, further modification of each of Janakiev and Yokoyama to have used a pressure vessel of stainless steel, as suggested by NuScale, would have been obvious to one of ordinary skill in the art.
In re Williams, 36 F.2d 436, 438 (CCPA 1929) ("It is a settled principle of law that a mere carrying forward of an original patented conception involving only change of form, proportions, or degree, or the substitution of equivalents doing the same thing as the original invention, by substantially the same means, is not such an invention as will sustain a patent, even though the changes of the kind may produce better results than prior inventions.").
Objection to the Abstract
The original Abstract remains pending. The Abstract is objected to because it includes an unclear long rambling sentence. It is unclear where one feature ends and another feature begins. It is suggested that the long rambling sentence be broken into several shorter clear sentences. An Abstract should include that which is new in the art to which the recited invention pertains. Correction is required. See MPEP § 608.01(b).
The following Abstract is presented for consideration:
A system includes a pressure vessel comprising a wall formed of structural layers stacked in a column. The layers define a primary internal volume and a set of infrastructure receptacles arranged above the primary internal volume. Nuclear fuel is arranged in the primary internal volume. The receptacles contain therein a heat exchanger and a pump. A primary coolant circuit includes the primary internal volume, the heat exchanger, and the pump. A secondary coolant circuit extends through the wall and is fluidly isolated from the primary coolant circuit. The heat exchanger is configured to transfer thermal energy from primary working fluid in the primary coolant circuit to secondary working fluid in the secondary coolant circuit. The secondary working fluid circulates between the secondary coolant circuit in the wall and an external power generation system.
Objection to the Title
The original Title remains pending. The Title is objected to because it is not directed to the elected invention. The following Title is presented for consideration: “Nuclear System Having A Heat Exchanger Located Inside A Pressure Vessel Wall That Is Formed Of Stacked Steel Layers”.
Allowable Subject Matter
Claims 8-9 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Response to Arguments
Applicant’s arguments have been considered but are moot because the new ground of rejection relies on new references which meet the features argued.
It is conventional in the art for stainless steel liners to abut reactor pressure vessel walls to provide corrosion protection thereto. The liners function as a seal to prevent corrosive fluid from contacting the vessel walls. The liners when heated will expand in all directions, including radially and vertically.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, 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 nonprovisional extension fee (37 CFR 1.17(a)) 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 mailing 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 and/or the specification.
The Applied References
For Applicant’s benefit, portions of the applied reference(s) have been cited (as examples) to aid in the review of the rejection(s). While every attempt has been made to be thorough and consistent within the rejection, it is noted that the prior art must be considered in its entirety by Applicant, including any disclosures that may teach away from the claims. See MPEP 2141.02 (VI).
Contact Information
Examiner Daniel Wasil can be reached at (571) 272-4654, on Monday-Thursday from 10:00-4:00 EST. Supervisor Jack Keith (SPE) can be reached at (571) 272-6878.
/DANIEL WASIL/
Examiner, Art Unit 3646
Reg. No. 45,303
/JACK W KEITH/Supervisory Patent Examiner, Art Unit 3646
Prosecution Insights