Prosecution Insights
Last updated: May 04, 2026
Application No. 18/204,683

DIRECT BATH SMELTING PROCESS WITH MANAGEMENT OF PERIPHERAL COLD ZONES AT THE METAL-SLAG INTERFACE

Non-Final OA §102§103
Filed
Jun 01, 2023
Priority
Jun 15, 2022 — provisional 63/352,492
Examiner
MORALES, RICARDO D
Art Unit
1738
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Nucor Corporation
OA Round
1 (Non-Final)
81%
Grant Probability
Favorable
1-2
OA Rounds
0m
Est. Remaining
98%
With Interview

Examiner Intelligence

Grants 81% — above average
81%
Career Allowance Rate
351 granted / 433 resolved
+16.1% vs TC avg
Strong +17% interview lift
Without
With
+17.2%
Interview Lift
resolved cases with interview
Typical timeline
2y 8m
Avg Prosecution
34 currently pending
Career history
467
Total Applications
across all art units

Statute-Specific Performance

§101
0.6%
-39.4% vs TC avg
§103
56.6%
+16.6% vs TC avg
§102
21.5%
-18.5% vs TC avg
§112
19.2%
-20.8% vs TC avg
Black line = Tech Center average estimate • Based on career data from 433 resolved cases

Office Action

§102 §103
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 . Election/Restrictions Claims 14-20 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 03/20/2026. Claim Rejections - 35 USC § 102 The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action: A person shall be entitled to a patent unless – (a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention. Claim(s) 1-4 and 10-12 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Innes (US6368548B1). Regarding Claim 1, Innes teaches a method for direct smelting of metalliferous material and producing molten metal in a direct smelting vessel (abstract), the method comprising: injecting solid carbonaceous material through at least one injection lance (See Claim 1) extending into the direct smelting vessel such that solids penetrate at least partially into a molten metal layer in the direct smelting vessel (see Lance 11 of Figure 1), wherein a slag layer is floating on the molten metal layer (metal bath) (See Figure 1); and promoting metal mixing at a zone (17) immediately below the slag layer adjacent to a vessel wall of the direct smelting vessel (See Figure 1) Regarding Claim 2, wherein the metal mixing is considered to reduce a volume occupied by a stagnant region cold enough to be capable of supporting a semi-solid slag layer that restricts metal-slag heat transfer by creating a metal mixing region. Regarding Claim 3, the metal mixing maintains a temperature variation of 30 C in each region (See Col. 8, Lines 40-45) reading on the claimed limitation of maintaining an effective temperature delta between tapped metal at a forehearth and metal at the vessel wall of no greater than 40 °C. Regarding Claim 4, the metal mixing is promoted using the direct smelting vessel comprising: a split-level refractory [[floor]]hearth with two refractory floor levels comprising a first level having a first depth that supports a first metal depth 16 and a second level having a second depth that supports a second metal depth 15;wherein the second metal depth is greater than the first metal depth; and wherein the first depth that supports the first metal depth promotes the metal mixing by metal convection into and out of the zone below the slag layer adjacent to the vessel wall. (See Figure 1) Regarding Claims 10-11, wherein the metal mixing is promoted by injecting gas in the direct smelting vessel using one or more gas bubbling devices for promotion of metal convection to the zone below the slag layer adjacent to the vessel wall. (See Claim 1) wherein the gas comprises argon gas or nitrogen gas. (See claim 7) Regarding Claim 12, the metal mixing is promoted by using one or more pairs of solids injection lances 11 in the direct smelting vessel, wherein one branch of a pair of solids injection lances provides at least a majority of the injected feed solids for the pair of solids injection lances at any given time. (See Fig 1) Claim Rejections - 35 USC § 103 The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action: A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made. The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows: 1. Determining the scope and contents of the prior art. 2. Ascertaining the differences between the prior art and the claims at issue. 3. Resolving the level of ordinary skill in the pertinent art. 4. Considering objective evidence present in the application indicating obviousness or nonobviousness. Claim(s) 5-9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Innes (US6368548B1). Regarding Claim 5, Innes teaches the first level has a significantly greater cross sectional surface area than the second layer (Fig 1), but the prior art does not explicitly teach the first level comprises at least 70% of a cross-sectional area of the split-level refractory hearth. However, one of ordinary skill in the art seeking an acceptable cross-sectional area to use would, under routine experimentation, arrived at the claimed relationship for the purpose of finding a useable configuration to smelt metal products; (See MPEP 2144.05(II)(A)) Similarly, regarding Claims 6-9, the prior art is silent regarding the depth size of the first metal and second metal; however, one of ordinary skill in the art seeking to use an acceptable depth to operate the smelting unit would have arrived at the claimed first and second metal depth limitations under routine experimentation for the purpose of finding usable metal bath dimensions to smelt melt products. (See MPEP 2144.05(II)(A)) Any inquiry concerning this communication or earlier communications from the examiner should be directed to RICARDO D MORALES whose telephone number is (571)272-6691. The examiner can normally be reached Monday-Thursday 9 am- 4 pm. 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. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Sally Merkling can be reached at 5712726297. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /RICARDO D MORALES/Primary Examiner, Art Unit 1738
Read full office action

Prosecution Timeline

Jun 01, 2023
Application Filed
Apr 08, 2026
Non-Final Rejection — §102, §103 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12605762
THREE-DIMENSIONAL SCREEN PRINTING METHOD, COMPONENT PRODUCIBLE BY MEANS OF SAID METHOD, AND SCREEN PRINTING MASK
3y 4m to grant Granted Apr 21, 2026
Patent 12599970
DEVICE AND METHOD FOR ADDITIVE MANUFACTURING UNDER PROTECTIVE GAS
3y 3m to grant Granted Apr 14, 2026
Patent 12599964
BONDING COMPOSITION, CONDUCTOR BONDING STRUCTURE, AND METHOD FOR PRODUCING SAME
2y 2m to grant Granted Apr 14, 2026
Patent 12595537
TIN BLACKPLATE FOR PROCESSING AND METHOD FOR MANUFACTURING SAME
3y 10m to grant Granted Apr 07, 2026
Patent 12595526
HOT-ROLLED STEEL SHEET FOR HYPER TRAIN TUBE, AND MANUFACTURING METHOD FOR SAME
2y 10m to grant Granted Apr 07, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

Strategy Recommendation AI-generated — please review before filing

Get a prosecution strategy drawn from examiner precedents, rejection analysis, and claim mapping.
Typically takes 5-10 seconds — AI-generated, attorney review required before filing

Prosecution Projections

1-2
Expected OA Rounds
81%
Grant Probability
98%
With Interview (+17.2%)
2y 8m (~0m remaining)
Median Time to Grant
Low
PTA Risk
Based on 433 resolved cases by this examiner. Grant probability derived from career allowance rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month