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 .
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 11-18 are rejected under 35 U.S.C. 103 as being unpatentable over Sasaki et al. (WO-2020044988-A1; herein English machine translation used for all citations) (previously cited) in view of Nishiyama (US 20190330724 A1) (newly cited).
Regarding claim 11, Sasaki teaches a duplex stainless steel pipe having a composition that comprises, in mass%, C: 0.005 to 0.08%, Si: 0.01 to 1.0%, Mn: 0.01 to 10.0%, Cr: 20 to 35%, Ni: 1 to 15%, Mo: 0.5 to 6.0%, N: 0.005 to 0.150%, and the balance being Fe and incidental impurities, and having a microstructure with a ferritic phase and an austenitic phase (Sasaki, Par. 0018 and Claim 1). Sasaki’s content ranges lie within the claimed ranges of 0.005 to 0.150%, 1.0% or less, 10.0% or less, 11.5 to 35%, 0.5 to 15%, 0.5 to 6.0%, and less than 0.400% respectively and therefore satisfies the claimed ranges, see MPEP 2131.03. Sasaki teaches the duplex stainless steel pipe has an axial tensile yield strength of 689 MPa or more (Sasaki, Par. 0018, 0057, and Claim 1), which is the same as the claimed range and therefore satisfies the claimed range, see MPEP 2131.03.
Sasaki is silent regarding the pipe having an outer surface and inner surface each having an oxide layer having an average thickness of 1.0 µm or more, wherein the oxide layer is a spinel-type oxide layer.
Nishiyama teaches a steel pipe comprising oxide layer (oxide layer C) on an outer an inner surface of the steel pipe (see “entire base material”) (Nishiyama, Par. 0002, 0021, 0045, 0099-0103, 0110, 0116-0119, and Figs 1-2). Nishiyama teaches the oxide layer is a spinel-type oxide layer (Nishiyama, Par. 0116-0119). Nishiyama teaches the oxide layer has an average thickness of at least 10 µm (Nishiyama, Par. 0126), which lies within the claimed range of 1.0 µm or more and therefore satisfies the claimed range, see MPEP 2131.03.
Sasaki and Nishiyama are analogous art as they both teach steel pipes. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have included the oxide layer of Nishiyama on the inner and outer surface of Sasaki. This would allow for improved heat transfer characteristics and steam oxidation resistance properties (Nishiyama, Par. 0001, 0016, 0110, and 0120).
Regarding claim 12, modified Sasaki teaches the oxide layers are formed over the entire inner and outer surfaces of the pipe and therefore satisfies the limitation of the oxide layer covering at least 50% of the outer and inner surfaces of the pipe, see MPEP 2123 (Nishiyama, Par. 0103).
Regarding claims 13-14, modified Sasaki teaches an axial compressive yield strength-to-axial tensile yield strength ratio of 0.85 to 1.15 (Sasaki, Par. 0058 and Claim 1), which is the same as the claimed range and therefore satisfies the claimed range, see MPEP 2123.
Regarding claims 15-18, modified Sasaki teaches the composition may further comprise 0.1 to 6 W by mass (Sasaki, Claim 3), which lies within the claimed range of 6.0 % or less and therefore satisfies the claimed range, see MPEP 2131.03.
Response to Arguments
Applicant’s remarks and amendments filed 07 July 2026 have been fully considered.
Applicant requests withdrawal of the objection and rejections under 35 USC § 112 set forth in the previous office action.
The objection and rejections under 35 USC § 112 set forth in the previous office action have been withdrawn due to the present claim amendments.
Regarding arguments directed to the rejections over prior art, Applicant argues that Hidaka does not teach a spinel-type oxide layer. This is found moot.
The grounds of rejection have been updated above in view of the present claim amendments. The new grounds of rejection no longer rely upon Hidaka to teach the claimed oxide layer and instead rely upon newly cited Nishiyama to teach the claimed spinel-type oxide layer.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. 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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to THOMAS J KESSLER JR whose telephone number is (571)272-3075. The examiner can normally be reached 7:30-5:30 M-Th.
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/THOMAS J KESSLER/Examiner, Art Unit 1782
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