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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 3/19/2026 has been entered.
Status of the Claims
The status of the claims as filed in the reply dated 2/12/2026 are as follows:
Claims 1, 10, and 17 are amended,
Claims 6-8, 15, and 18-24 are canceled,
Claims 25-26 are new,
Claims 1-5, 9-14, 16-17, and 25-25 are currently pending.
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.
Claim(s) 1-5, 9-10, 13-14, 16, 25, and 26 is/are rejected under 35 U.S.C. 103 as being unpatentable over Dowling (US 4,235,081, previously cited) in view of Ferguson et al. (US 2020/0333093, herein Ferguson, previously cited) and in further view of Paseman (U.S. Patent No. 4,605,028).
In regards to claim 1, Dowling discloses
A system (Figs.1-5) for exchanging heat between a first material (air) and a second material (refrigerant), comprising:
a shell (Fig.5, 24) for containing the first material therein;
a plurality of tubes (86) disposed within the shell for containing the second material therein, a tube sheet (88) disposed at an end of the shell for restricting flow of the second material to the shell; and
at least one collector conduit (28, 30) disposed exterior to the shell for receiving at least one end of the plurality of tubes, wherein at least one of the plurality of tubes extend through the tube sheet to the collector conduit (Fig.5).
Dowling does not explicitly disclose a cleaning tool disposed within the at least one collector conduit comprising a nozzle for spraying one of the ends of the plurality of tubes with a fluid during cleaning, wherein the cleaning tool is capable of being rotated to a first position in which the nozzle is aligned with said one of the ends of the plurality of tubes and the fluid is permitted to flow from the nozzle; and further wherein the cleaning tool is capable of being rotated to a second position in which the nozzle is not aligned with said one of the ends of the plurality of tubes and the fluid is not permitted to flow from the nozzle.
Ferguson teaches a cleaning tool comprising a nozzle for spraying one of the ends of the plurality of tubes with a fluid during cleaning, wherein the cleaning tool is capable of being rotated to a first position in which the nozzle is aligned with said one of the ends of the plurality of tubes and the fluid is permitted to flow from the nozzle; and further wherein the cleaning tool is capable of being rotated to a second position in which the nozzle is not aligned with said one of the ends of the plurality of tubes and the fluid is not permitted to flow from the nozzle (Figs.1-9 and paragraph 11, etc.). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Dowling’s heat exchanger to include a cleaning tool as taught by Ferguson in order to provide easy maintenance of the heat exchanger and increase its lifespan.
However, Dowling, as modified, does not explicitly disclose the cleaning tool comprising a housing, the nozzle being within the housing, and an opening positioned within the housing for directing the fluid through the housing to the nozzle, the nozzle comprising a piston and a spring for regulating flow of the fluid. Paseman, however, discloses a cleaning tool for heat exchanger tubes (fig 1) wherein the cleaning tool comprises a housing (40, H, 34, 12, 42), a nozzle (22, 18, 36) being within the housing, and an opening (for inlet 16) positioned within the housing for directing the fluid through the housing to the nozzle, the nozzle comprising a piston (20) and a spring (36) for regulating flow of the fluid (col 2, line 53-col 3, line 49). Paseman teaches that this design allows for different lances to be inserted for different cleaning applications (col 1, line 54 – col 2, line 35). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention for Dowling, as modified, to provide the cleaning tool design of Paseman in order to allow for different lances to inserted depending on the tubes of the heat exchanger being cleaned.
In regards to claim 2, the combination of Dowling, Ferguson, and Paseman discloses all previous claim limitations. Dowling discloses that the at least one collector conduit comprises an input collector conduit (30) and an output collector conduit (28), wherein at least one input end of the tubes are in fluid communication with the input collector conduit for receiving the second material from the input collector conduit, and wherein at least one output end of the tubes are in fluid communication with the output collector conduit for delivering the second material to the output collector conduit (Fig.5).
In regards to claim 3, the combination of Dowling, Ferguson, and Paseman discloses all previous claim limitations. Dowling discloses that the plurality of tubes consists essentially of duplex stainless steel, austenitic stainless steel, or combinations thereof (col.4 lines 22-26).
In regards to claim 4, the combination of Dowling and Ferguson discloses all previous claim limitations. Dowling discloses a pair of longitudinal baffles (77-84) disposed within the shell adjacent to opposite sides of the shell.
In regards to claim 5, the combination of Dowling, Ferguson, and Paseman discloses all previous claim limitations. Dowling discloses that the pair of longitudinal baffles is disposed near an inlet of the shell, near an outlet of the shell, or at multiple locations along a length of the shell (Fig.5).
In regards to claim 9, the combination of Dowling, Ferguson, and Paseman discloses all previous claim limitations. Dowling discloses that the plurality of tubes comprises up to twenty tubes arranged in parallel, and wherein each tube is arranged to have up to twelve passes (Fig.5).
In regards to claim 10, Dowling discloses
A process for cooling a gas stream comprising:
introducing a gas stream (from inlet 30) to one or more heat exchangers (24) for cooling the gas stream, the one or more heat exchangers comprising:
a shell (Fig.5) for containing a cooling medium (via inlet 22) therein;
a plurality of tubes (86) disposed within the shell for containing the gas stream therein, a tube sheet (88) disposed at an end of the shell for restricting flow of the gas stream to the shell; and
at least one collector conduit (28, 30) disposed exterior to the shell for receiving at least one of the ends of the plurality of tubes, wherein at least one of the plurality of tubes extend through the tube sheet to the collector conduit (Fig.5).
Dowling does not disclose a cleaning tool disposed within the at least one collector conduit comprising a nozzle for spraying one of the ends of the plurality of tubes with a fluid during cleaning, wherein the cleaning tool is capable of being rotated to a first position in which the nozzle is aligned with said one of the ends of the plurality of tubes and the fluid is permitted to flow from the nozzle; and further wherein the cleaning tool is capable of being rotated to a second position in which the nozzle is not aligned with said one of the ends of the plurality of tubes and the fluid is not permitted to flow from the nozzle.
Ferguson teaches a cleaning tool comprising a nozzle for spraying one of the ends of the plurality of tubes with a fluid during cleaning, wherein the cleaning tool is capable of being rotated to a first position in which the nozzle is aligned with said one of the ends of the plurality of tubes and the fluid is permitted to flow from the nozzle; and further wherein the cleaning tool is capable of being rotated to a second position in which the nozzle is not aligned with said one of the ends of the plurality of tubes and the fluid is not permitted to flow from the nozzle (Figs.1-9 and paragraph 11).It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Dowling’s heat exchanger to include a cleaning tool as taught by Ferguson in order to provide easy maintenance of the heat exchanger and increase its lifespan.
However, Dowling, as modified, does not explicitly disclose the cleaning tool comprising a housing, the nozzle being within the housing, and an opening positioned within the housing for directing the fluid through the housing to the nozzle, the nozzle comprising a piston and a spring for regulating flow of the fluid. Paseman, however, discloses a cleaning tool for heat exchanger tubes (fig 1) wherein the cleaning tool comprises a housing (40, H, 34, 12, 42), a nozzle (22, 18, 36) being within the housing, and an opening (for inlet 16) positioned within the housing for directing the fluid through the housing to the nozzle, the nozzle comprising a piston (20) and a spring (36) for regulating flow of the fluid (col 2, line 53-col 3, line 49). Paseman teaches that this design allows for different lances to be inserted for different cleaning applications (col 1, line 54 – col 2, line 35). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention for Dowling, as modified, to provide the cleaning tool design of Paseman in order to allow for different lances to inserted depending on the tubes of the heat exchanger being cleaned.
In regards to claim 13, the combination of Dowling, Ferguson, and Paseman discloses all previous claim limitations. Dowling discloses that the plurality of tubes consists essentially of duplex stainless steel, austenitic stainless steel, or combinations thereof (col.4 lines 22-26).
In regards to claim 14, the combination of Dowling, Ferguson, and Paseman discloses all previous claim limitations. Dowling discloses that the one or more heat exchangers further comprise a pair of longitudinal baffles (77-84) disposed within the shell adjacent to opposite sides of the shell, but does not disclose that the one or more heat exchangers further comprise a cleaning tool disposed within the at least one collector conduit, the cleaning tool comprising a nozzle for spraying one of the ends of the plurality of tubes with a fluid at a pressure up to 80 MPa.
Ferguson teaches a cleaning tool comprising a nozzle for spraying one of the ends of the plurality of tubes with a fluid during cleaning, wherein the cleaning tool is capable of being rotated to a first position in which the nozzle is aligned with said one of the ends of the plurality of tubes and the fluid is permitted to flow from the nozzle; and further wherein the cleaning tool is capable of being rotated to a second position in which the nozzle is not aligned with said one of the ends of the plurality of tubes and the fluid is not permitted to flow from the nozzle (Figs.1-9 and paragraphs 11 and 41, etc.).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Dowling’s heat exchanger to include a cleaning tool as taught by Ferguson in order to provide easy maintenance of the heat exchanger and increase its lifespan.
In regards to claim 16, the combination of Dowling, Ferguson, and Paseman discloses all previous claim limitations. Dowling discloses that the plurality of tubes comprises up to twenty tubes arranged in parallel, and wherein each tube is arranged to have up to twelve passes (Fig.5).
In regards to claim 25, the combination of Dowling, Ferguson, and Paseman discloses all previous claim limitations. Dowling, as modified, discloses wherein in the second position (as taught by Ferguson, see rejection of claim 1), the piston (20, Paseman) of the nozzle is forced against an inner wall of the collector conduit (28, 30, Dowling) by the spring (36, Paseman).
In regards to claim 25, the combination of Dowling, Ferguson, and Paseman discloses all previous claim limitations. Dowling, as modified, discloses wherein in the second position (as taught by Ferguson, see rejection of claim 10), the piston (20, Paseman) of the nozzle is forced against an inner wall of the collector conduit (28, 30, Dowling) by the spring (36, Paseman).
Claims 11-12 are rejected under 35 U.S.C. 103 as being unpatentable over Dowling, Ferguson, and Paseman in view of Murray (US 4,156,457) and Richter et al. (US 3,915,224).
In regards to claims 11 and 12, the combination of Dowling, Ferguson, and Paseman discloses all previous claim limitations. Dowling does not disclose that the gas stream is directed from a separator in fluid communication with an outlet of a polyethylene producing reactor to the one or more heat exchangers to form a cooled gas stream, wherein the cooled gas stream is recycled to a compressor in fluid communication with an inlet of the polyethylene producing reactor, wherein the gas stream is introduced to one or more boilers arranged in series for producing steam before being introduced to the one or more heat exchangers.
However, this is merely the intended use of the heat exchanger, and one of ordinary skill in the art before the effective filing date of the claimed invention would have found it obvious to apply Dowling’s heat exchanger with a polyethylene producing reactor and a boiler as similarly taught by Murray (see col.1 lines 5-15) and Richter (see col.1 lines 9-17).
Allowable Subject Matter
Claim 17 allowed.
The following is a statement of reasons for the indication of allowable subject matter: Claim 17 is allowable at least for the reason that the prior art of record does not disclose the process as claimed.
Response to Arguments
Applicant's arguments filed 2/12/2026 have been fully considered but they are not persuasive.
Applicant argues that Dowling and Ferguson fail to teach the spring and piston of the amended claims. However, newly cited Paseman is now being relied upon to teach these limitations.
Conclusion
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/HARRY E ARANT/Primary Examiner, Art Unit 3763