Frank F Kraft

US Patent:

6536255, Mar 25, 2003

Filed:

Dec 7, 2000

Appl. No.:

09/732141

Inventors:

Frank F. Kraft - Adrian MI

Assignee:

Brazeway, Inc. - Adrian MI

International Classification:

B21C 2300

US Classification:

72256, 7237024, 7237025, 29890053, 165177

Abstract:

This invention is a process for making micro-multiport tubing for use in heat exchangers. The tubing is a flat body with a row of side-by-side passageways, which are separated by upright webs. Processing of this tubing involves extrusion, a straightening and cutting operation, a rolling step to reduce the thickness of the flat body and to obtain ultra small voids, assembly and furnace brazing of the heat exchanger. This invention improves the grain size of the metal in the tubing and also improves the metallurgical strength of the tubing. There is at least 10 percent change in material thickness. The strain is concentrated at the center of the web and results in at least enough cold work to produce fine recrystallized grains during the brazing thermal cycle. The amount of grain growth is controlled and the improvement in the metallurgical strength is achieved.

US Patent:

6644394, Nov 11, 2003

Filed:

Jun 25, 2002

Appl. No.:

10/183099

Inventors:

Frank F. Kraft - Albany OH
Dave W. Skrzypchak - Adrian MI

Assignee:

Brazeway, Inc. - Adrian MI

International Classification:

F28F 120

US Classification:

165181, 179183, 29890053, 138 38

Abstract:

A heat exchanger tube of the present invention has first and second surfaces with a longitudinal length and a lateral width. At least one of the surfaces has a plurality of striae that extend along a portion of the width of the tube. The tube has at least one passageway that allows a fluid to flow therethrough. The striae minimize and/or prevent unwanted flow of molten braze alloy along die-lines in the tube formed as part of the extruding process. The striae can be formed in the tube by rollers having projections that extend radially outward. The projections form the striae in the tube as the tube passes along the outer surface of the roller. The striae can be advantageously formed in the tube as part of the overall extruding process or subsequent to the extruding of the tube during the sizing process.

US Patent:

8191393, Jun 5, 2012

Filed:

Dec 11, 2007

Appl. No.:

12/517484

Inventors:

Frank F. Kraft - Albany OH, US

Assignee:

Ohio University - Athens OH

International Classification:

B21C 23/04

US Classification:

72264, 72268, 72269

Abstract:

An apparatus and method are provided for extruding a micro-channel tube () from a non-aluminum metal or alloy such as copper. The micro-channel tube is formed by simultaneously extruding two rectangular shaped billets () to form a top portion of the micro-channel tube and a bottom portion of the micro-channel tube in parallel. The top and bottom portions are then joined during the extrusion process (e. g. , within a die assembly) to form the micro-channel tube ().

US Patent:

20020121120, Sep 5, 2002

Filed:

Dec 21, 2001

Appl. No.:

10/032054

Inventors:

Frank Kraft - Albany OH, US
Jerry Ziems - Sylvania OH, US
Charles Downing - Onsted MI, US

International Classification:

B21C023/08

US Classification:

072/254000, 072/260000, 072/261000

Abstract:

A method of manufacturing micro-multi-port tubing including actuating a hydraulic press to apply a force to a billet to extrude material through a die opening. The die opening defines at least two distinct segments to produce a single, unitary, continuous micro-multi-port extrusion strand having at least two distinct segments being interconnected by a web section. The method further includes separating the single, unitary, continuous micro-multi-port strand to substantially remove and/or reshape the web section to define at least two separate and independent micro-multi-port tubing segments from a single extrusion strand.

US Patent:

20020125004, Sep 12, 2002

Filed:

Jan 11, 2001

Appl. No.:

09/758743

Inventors:

Frank Kraft - Adrian MI, US

International Classification:

F16L009/18
F16L011/00

US Classification:

165/180000, 138/115000, 165/905000

Abstract:

This invention is a process for making improved micro-multiport tubing for use in heat exchangers. A multivoid heat exchanger tube is extruded from aluminum alloy billet. The alloy is a composition of cooperative elements which act with the aluminum to prevent recrystallization and grain growth which result in the necessary strength and duality of characteristics in the tubes. The composition of the alloy that is added to aluminum is some or all of the following: silicon, iron, copper, magnesium, manganese, zinc and titanium. The cold work during processing of the heat exchanger is limited to further retain the small grains.

US Patent:

61929786, Feb 27, 2001

Filed:

Oct 27, 1999

Appl. No.:

9/427864

Inventors:

Matthew M. Guzowski - Aurora OH
Frank F. Kraft - Adrian MI
Henry R. McCarbery - Palmyra MI

Assignee:

Brazeway, Inc. - Adrian MI

International Classification:

F28F 102
B21D 5306

US Classification:

165177

Abstract:

This invention is a process for making micro-multiport tubing for use in automobile air conditioner heat exchangers. The tubing is a flat body with a row of side-by-side passageways, which are separated by upright webs. Processing of this tubing involves extrusion, a straightening and cutting operation, assembly and furnace brazing of the condenser. This invention improves the grain size of the metal in the tubing and also improves the metallurgical strength of the tubing. Ports are formed in the tubing during extrusion. These ports are separated by webs and the webs are extruded so that they have a reduced thickness at their centers. In response to successive cold working of the body, the webs are changed in shape to a more uniform thickness state. Stated other wise, in this invention, the webs are initially of hour glass shape such that when there is five percent change in material thickness, the strain is concentrated at the center of the web and results in at least fifteen percent cold work. With fifteen percent cold work or more, the amount of grain growth is controlled and the improvement in the metallurgical strength is achieved.

US Patent:

20220389540, Dec 8, 2022

Filed:

Jun 7, 2022

Appl. No.:

17/834876

Inventors:

- Albany OH, US
Frank F Kraft - Albany OH, US

Assignee:

MetalKraft Technologies, LLC - Albany OH

International Classification:

C22C 9/00
C23C 16/26
B21C 23/24

Abstract:

A conductor material includes a metal matrix, and a first carbon allotrope distributed within the metal matrix, the first carbon allotrope being aligned with a direction of electric current flow through a length of the metal matrix. The metal matrix and the first carbon allotrope have an electrical interfacial coherency.

US Patent:

20200027624, Jan 23, 2020

Filed:

Jul 17, 2019

Appl. No.:

16/514785

Inventors:

Shenjia Zhang - Zionsville IN, US
Sathish Kumar Ranganathan - Avon IN, US
Keerti Sahithi Kappagantula - Athens OH, US
Frank F. Kraft - Albany OH, US

International Classification:

H01B 1/02
H01B 1/04
H01B 13/00

Abstract:

Cables including conductors formed form ultra-conductive copper wires which have a lower temperature coefficient of resistance are disclosed. Methods of making the cables including conductors with ultra-conductive copper wires are further disclosed.