WO2023146677A1

WO2023146677A1 - Flame sterilization tuber seed cutter devices, systems, and methods of use thereof

Info

Publication number: WO2023146677A1
Application number: PCT/US2022/070351
Authority: WO
Inventors: Tyler A. THOMPSON
Original assignee: Colorado State University Research Foundation
Priority date: 2022-01-26
Filing date: 2022-01-26
Publication date: 2023-08-03

Abstract

A tuber seed cutter sterilization device is disclosed. The tuber seed cutter is configured to receive a flammable gas and sterilize a tuber seed cutter having a rotational blade and a tuber conveyer, the rotational blade is configured to rotate about a longitudinal axis of a rotational shaft. The tuber seed cutter includes a fluid channel configured to receive the flammable gas at an inlet port and direct the flammable gas to a pair of outlet ports, each outlet port of the pair of outlet ports positioned at opposite axial sides of the rotational blade. The flammable gas is configured to be ignited into a flame at each outlet port of the pair of outlet ports and each flame of the pair of outlet ports is configured to heat opposite outer surfaces of the rotational blade.

Description

FLAME STERILIZATION TUBER SEED CUTTER DEVICES, SYSTEMS, AND METHODS OF USE THEREOF

FIELD OF THE INVENTION

[0001 ] This application relates to sterilization tuber seed cutter devices, systems, and methods of use thereof. In particular, this application relates to flame sterilization tuber seed cutter devices, systems, and methods of use thereof.

BACKGROUND OF THE INVENTION

[0002] Tubers, such as potatoes, are cultivated using a process known as vegetative propagation, which involves planting a portion of the parent to grow new plants. In practice, this typically involves cutting a tuber into one or more smaller pieces using automated machinery or with a knife. Either process, however, poses a risk for mechanical transmission of bacterial, fungal, and/or viral pathogens by transmitting pathogens from an infected tuber to a non-infected tuber via a repeatedly used blade.

[0003] Currently, growers may sanitize seed cutting equipment between seed lots using, for example, high-temperature water, chlorinated-solutions and quaternary ammonium compounds. Although this practice is effective in containing disease spread between seed lots, there is an invariable risk for disease transmission while cutting potatoes within a seed lot. Thus, a need exists to help reduce disease transmission within a seed lot.

SUMMARY OF THE INVENTION

[0004] In a first exemplary embodiment of the present invention, tuber seed cutter sterilization device is disclosed. The tuber seed cutter may be configured to receive a flammable gas and sterilize a tuber seed cutter having at least one rotational blade and a tuber conveyer, the at least one rotational blade may be configured to rotate about a longitudinal axis of a rotational shaft. The device may include a fluid channel configured to receive the flammable gas at an inlet port and direct the flammable gas toward at least one pair of outlet ports, each pair of outlet ports positioned at opposite axial sides of the at least one rotational blade. In addition, the flammable gas may be configured to be ignited into a flame at each one of the pair of outlet ports and each flame at the pair of outlet ports may be configured to heat opposite outer surfaces of the at least one rotational blade.

[0005] In some versions of the first embodiment, the flammable gas may include acetylene, the flammable gas may include compressed air, and the acetylene to compressed air ratio may be between 4 and 12. Also, the tuber seed cutter may include a heat shield positioned above the at least one rotational blade and configured to improve heat retention of the at least one rotational blade and the heat shield may include an exhaust vent. In addition, the outer surfaces of the at least one rotational blade may be substantially planar and perpendicular to the longitudinal axis and each of the pair of outlet ports may be configured to emit the flammable gas parallel to the outer surfaces of the at least one rotational blade and the outer surfaces of the at least one rotational blade may be substantially planar and perpendicular to the longitudinal axis and each of the pair of outlet ports may be configured to emit the flammable gas at a nonparallel angle to the outer surfaces of the at least one rotational blade. Also, during rotation of the at least one rotational blade, the opposite outer surfaces of the at least one rotational blade are configured to rotate against the respective flames and have a dwell time against the respective flames between 0.004 seconds and 0.016 seconds and each flame is configured to heat a portion of the respective opposite outer surface to a temperature between 350° F and 500° F and the portion of the respective outer surface is configured to cool to a temperature between 220° F and 280° F before rotating against the respective flame again.

[0006] In a second exemplary embodiment of the present invention, a tuber seed cutter assembly configured to receive a flammable gas is disclosed. The assembly may include at least one rotational blade configured to cut a tuber into a tuber seed, the at least one rotational blade may be configured to rotate about a longitudinal axis of a rotational shaft. The assembly may also include a conveyor configured to convey the tuber to the at least one rotational blade and a fluid channel configured to receive the flammable gas at an inlet port and direct the flammable gas toward at least one pair of outlet ports, each pair of outlet ports may be positioned at opposite axial sides of the at least one rotational blade.

[0007] In some versions of the second exemplary embodiment, the flammable gas may include acetylene, the flammable gas may include compressed air, and the acetylene to compressed air ratio may be between 4 and 12. Also, the tuber seed cutter assembly may include a heat shield positioned above the at least one rotational blade and configured to improve heat retention of the at least one rotational blade and the heat shield may include an exhaust vent. In addition, the outer surfaces of the at least one rotational blade may be substantially planar and perpendicular to the longitudinal axis and each of the pair of outlet ports may be configured to emit the flammable gas parallel to the outer surfaces of the at least one rotational blade and the outer surfaces of the at least one rotational blade may be substantially planar and perpendicular to the longitudinal axis and each of the pair of outlet ports may be configured to emit the flammable gas at a nonparallel angle to the outer surfaces of the at least one rotational blade. Also, during rotation of the at least one rotational blade, the opposite outer surfaces of the at least one rotational blade are configured to rotate against the respective flames and have a dwell time against the respective flames between 0.004 seconds and 0.016 seconds and each flame is configured to heat a portion of the respective opposite outer surface to a temperature between 350° F and 500° F and the portion of the respective outer surface is configured to cool to a temperature between 220° F and 280° F before rotating against the respective flame again.

[0008] In a third exemplary embodiment of the present invention, a method for cutting a tuber seed with a tuber seed cutting assembly is disclosed. The method may include conveying, with a conveyor, a first tuber to at least one rotational blade, cutting, with the at least one rotational blade, the first tuber into a first tuber seed, and sterilizing, with at least one pair of flames, the at least one rotational blade by simultaneous heating opposite surfaces of the at least one rotational blade with respective oppositely positioned flames of the at least one pair of flames. [0009] In some versions of the third exemplary embodiment, the method may include rotating the opposite outer surfaces of the at least one rotational blade against the respective flames such that the opposite outer surfaces have a dwell time against the respective flames between 0.004 seconds and 0.016 seconds, heating a portion of the opposite outer surfaces against the respective flames to a temperature between 350° F and 500° F, and cooling the portion of the opposite outer surfaces to a temperature between 220° F and 280° F before rotating the portion of the opposite outer surfaces against the respective flames again. In addition, the method may include generating a flame by igniting a flammable gas mixture of at least acetylene and compressed air and the acetylene to compressed air ratio may be between 4 and 12.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The foregoing summary, as well as the following detailed description of preferred embodiments of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there are shown in the drawings embodiments which are presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. In the drawings:

[0011] Figure 1 is a side diagram view of a flame sterilization tuber seed cutter according to an exemplary embodiment of the present disclosure.

[0012] Figure 2 is a top diagram view of the flame sterilization tuber seed cutter of Figure 1 .

[0013] Figure 3 is a front, top, side perspective diagram view of a portion of the flame sterilization tuber seed cutter of Figure 1 .

[0014] Figure 4 is an enlarged side diagram view of a portion of the flame sterilization tuber seed cutter of Figure 1. DETAILED DESCRIPTION

[0015] Reference will now be made in detail to the exemplary embodiments, which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

[0016] Described herein are tuber seed cutter sterilization devices, systems, and methods of use thereof. Figures 1 -4 depict an exemplary embodiment of a tuber seed cutter assembly 100 for cutting a tuber 200, such as a potato or other tuber, into a tuber seed 201 (Fig. 3). As shown in Figs. 1 and 2, the assembly 100 may include a tuber conveyer 110 for conveying or transporting one or more tubers 200 to a blade array 140. The tuber conveyor 110 (which may also be known as a splitter table) may include a plurality of roller arrays 112 with each roller array 112 including a plurality of rollers 114 axially spaced apart from each other along a translating shaft 116. Each axially successive roller 114 in the roller array 112 defines a gap 118 configured to help seat a tuber 200 and to allow a blade 142 from the blade array 140 to partially pass through in a side- and top-overlapping arrangement. (See an exemplary top-overlapping arrangement in Fig. 1 and an exemplary side-overlapping arrangement in Fig. 2.)

[0017] The tuber conveyer 110 may form a continuous loop of the roller arrays 112 such that each roller array 112 has adjacent roller arrays 112 positioned in front and behind it. The translating shafts 116 may be held by a belt or chain 120 such that translation of the chain 120 along a track causes translation of the roller array 112. The chain 120 may be actuated by a motor (not shown) coupled to a sprocket 122, such that rotation of the sprocket 122 causes linear translation of the translating shafts 116 toward the blade array 140 on a top-side of the tuber conveyer 110 and away from the blade array 140 on a bottom-side of the tuber conveyer 110. See Fig. 1 . In some embodiments, the rollers 114 may be configured to rotate freely on the translating shaft 116 and in other embodiments, the rollers 114 may be fixed to help urge the tuber 200 into the blade 142. In other embodiments not shown, the tuber conveyer 110 may have a belt instead of rollers 114 for conveying the tubers 200 toward the blade array 140 or may rely on gravity in a downwardly-sloped shoot to convey the tubers 200 toward the blade array 140.

[0018] The blades 142 in the blade array 140 may be axially spaced apart by a distance substantially equal to the thickness of the rollers 114 to allow the rollers to pass alongside a blade 142 in overlapping arrangement on each longitudinal side thereof. In some embodiments not shown, the blade array 142 may be rotated by the same motor as the motor for rotating the sprocket 122 or may be rotated by a separate motor. In either case, the blade array 140 may be configured to rotate at approximately 0.8 to 0.9 Hz, for example, in the opposite direction of the sprocket 122. The blades 142 may comprise metal or steel alloys that have high emissive and reflective surfaces. In some exemplary embodiments, the blades 142 may comprise wrought iron due to its low cost and durability, but in other embodiments, the blades 142 may comprise stainless steel. In some embodiments, outer surfaces 144 of the blades 142 may be treated by anodizing or surface coating. The blade 142 depicted in Fig. 4 may have a radius RB measuring approximately 9 inches. Hence, the linear speed of the cutting edge of the blade 142 is approximately between 60 and 70 inches per second. In other embodiments, the larger or smaller blades may be used and may be rotated at faster or lower speeds.

[0019] The tuber seed cutter assembly 100 may also include a sterilization unit 150. The sterilization unit 150 may be configured to sterilize each blade 142 by providing a flame 152 to heat the outer surfaces 144 of the blade 142 (see Figs. 2-4). As shown in Fig. 1 , the sterilization unit 150 may include an acetylene tank 154 containing acetylene gas and a compressed air tank 156 containing compressed air. In other embodiments, an air compressor may be used instead of a compressed air tank 156 to provide compressed air. The sterilization unit 150 may also include a fluid channel 158 having an inlet port 160 (Fig. 1 ) for receiving a mixture of acetylene and compressed air. The amount of acetylene and compressed air may be controlled using pressure regulators 154a, 156a attached to the acetylene and compressed air tanks 154, 156, respectively. The pressure regulators 154a, 156a may be configured to output a mixture of acetylene and compressed air in a ratio based on pressure/pressure of between 4 and 20, and preferably between 4 and 12. In an exemplary embodiment, at an elevation of 7,884 ft., the acetylene may be provided at 8.5 psig and the compressed air may be provided at 1 .25 psig. In another example, the acetylene may be provided at 8 psig and the compress air may be provided at 0.75 psig. One having ordinary skill in the art would recognize that the pressures may be adjusted based on a desired approximate flame size and elevation, such as reducing the amount of compressed air supplied at lower elevations to compensate for the higher amount of oxygen present in the atmosphere at these elevations. In other embodiments not shown, the compressed air tank 156 may be replaced with an oxygen tank and the pressure of the oxygen may be controlled to release substantially the same account of oxygen in terms of partial pressure as with the compressed air. In some embodiments, acetylene may be used without compressed air or additional oxygen. For example, acetylene may be provided between 8 and 12 psig or preferably between 8.5 and 10.5 psig.

[0020] As shown in Fig. 1 , the fluid channel 158 may include various supply tubing 162 that fluidically connects the pressure regulators 154a, 156a to a manifold 164. The supply tubing 162 may include the inlet port 160, which is where the gasses combine or enter as combined. As shown in Fig. 2, the manifold 164 may include a number of outlet ports 166, positioned in pairs on opposite sides of each blade 142 in the blade array 142. In other embodiments not shown, the fluid channel 158 may have dedicated tubes routed to each outlet 166 instead of the manifold 164 or may have a manifold upstream of the outlets 166 but with dedicated tubes routed to each outlet 166. The outlet ports 166 may have a diameter between 1/32 inch and 3/32 inch and preferably about 1/16 inch.

[0021 ] A pair of flames 152 are shown in Fig. 2 emanating from a respective pair of the outlet ports 166. The outlet ports 166 may be configured to emit the flammable gas substantially parallel to the outer surfaces 144 of the blade 142 such that a portion of the flame 152 contacts the outer surfaces 144 of the blade 142. The flame 152 may have a freestanding tear-drop or elliptical shape when not positioned adjacent to the blade 142 (i.e., an uninterrupted shape) such that it has a maximum width WF (see Fig. 4) between 1 inch and 1/4 inch, between 3/4 inch and 1/2 inch, or about 5/8 inch.

Based on the exemplary blade edge speeds discussed above, the blade may have a dwell time in the flame between 0.004 seconds and 0.016 seconds, between 0.006 seconds and 0.014 seconds, between 0.008 seconds and 0.012 seconds, or about 0.010 seconds. The flame 152 may have a radial length greater than the maximum size of the cut tuber seed 201 . For example, in embodiments where the maximum cut tuber size is 4 inches, the radial flame length is greater than 4 inches. As shown in Fig. 4, the radial flame length is calculated by the radius RB of blade 142 minus a radius RF up to the flame 152.

[0022] Returning to Fig. 2, each pair of outlet ports 166 may be axially spaced apart from the outer surface 144 of the blade, such that an innermost edge of the outlet port 166 is positioned axially offset from the outer surface 144 by a distance between 0 inch and 3/8 inch, between 1/16 inch and 5/16 inch, or preferably by about 1/4 inch.

[0023] As shown in Figs. 3 and 4, the outlet ports 166 may be openings or nozzles having a general emission angle a with respect to a horizontal plane of the manifold 164 in which the outlet ports 166 are configured to emit the flammable gas. The angle a may be 0 degrees such that the gas is emitted parallel to the horizontal plane. The gas may be emitted at an acute angle a with respect to the horizontal plane between 30 and 0 degrees, 45 and 0 degrees, between 60 and 0 degrees, or between 75 and 0 degrees. In some embodiments, the angle a may be between 30 and 75 degrees, between 45 and 75 degrees, or between 60 and 75 degrees. In some embodiments, the angle a may be between 30 and 60 degrees or between 45 and 60 degrees. In some embodiments, the angle a may be between 30 and 45 degrees.

[0024] As shown in Fig. 3, the flame 152 may be angularly positioned with respect to the blade 142 forming an angle [3 between where the flame 152 contacts the blade 142 and the general location where the blade 142 cuts the tuber 200. The angle [3 may be minimized to sterilize the blade 142 immediately after cutting the tuber 200 without heating the cut tuber seeds 201 , i.e., the flames 152 may be configured to heat the blade 142 above where the tuber seeds 201 are ejected from the blade 142. Minimizing the angle [3 also maximizes the angular distance, and consequently time, for the blade to cool off after passing through the flame 152 and before cutting another tuber 200. The angle [3 may be between 30 and 180 degrees, 30 and 150 degrees, between 30 and 120 degrees, between 30 and 90 degrees, or between 30 and 60 degrees. In some embodiments, the angle [3 may be between 60 and 180 degrees, 60 and 150 degrees, or between 60 and 120 degrees, or between 60 and 90 degrees. In some embodiments, the angle [3 may be between 90 and 180 degrees, 90 and 150 degrees, or between 90 and 120 degrees. In some embodiments, the angle [3 may be between 120 and 180 degrees or 120 and 150 degrees. In some embodiments, the angle [3 may be between 150 and 180 degrees.

[0025] Each of the parameters: angle a, angle f3, flame length (RB-RF), flame width WF, acetylene pressure, compressed air pressure, blade radius RB, and angular blade speed contribute to a temperature profile of the blade 142. The aforementioned parameters may be adjusted to produce an after-flame temperature TF (see Fig. 3) measured at a location 1 inch downstream from the flame at 1 inch from the blade edge and an after-cutting temperature Tc (see Fig. 4) measured at a location 1 inch downstream from the where the blade completes a cut with the tuber 200 at 1 inch from the blade edge. In some embodiments, the after-flame temperature TF may be between 350° F and 500° F, between 375° F and 475° F, between 400° F and 450° F, or about 425° F and the after-cutting temperature Tc may be between 220° F and 280° F, between 200° F and 260° F, or between 220° F and 240° F.

[0026] As shown in Fig. 1 , the sterilization unit 150 may also include a heat shield 168 positioned above the blade array 140. The heat shield 168 may comprise a reflective inner surface configured to reflect heat back toward the blade array 140. In addition, the heat shield 168 may help contain heated air to raise the ambient temperature of the air around the blades 142. It may be desirable to heat the ambient temperature of the air trapped under the heat shield 168 to lower the amount of heat needed to be generated by the flames 152 to sterilize the blades 142 but still allow the blades 142 to cool down to a temperature to provide effective cutting of and reduce thermal damage to the tubers 200.

[0027] In addition, the heat shield 168 may include an exhaust vent 170 to route the exhaust gasses outside or away from the tuber seed cutter assembly 100 or workers that may be in the proximity thereof. The exhaust vent 170 may further include a scrubber or filter to remove various gasses and soot from the exhaust gas.

[0028] An exemplary method for cutting the tuber 200 with a tuber seed cutter assembly 100 may be carried out with the following steps. The method may include providing a tuber seed cutter assembly, such as the tuber seed cutter assembly 100 discussed above or installing a sterilization unit 150 as discussed above onto a tuber seed cutter assembly. The method may also include, conveying, with the tuber conveyor 110, a first tuber 200, a second tuber 200, and then a plurality of tubers 200, to the blade array 140. The method may include cutting, with the blade array 140, the first tuber 200, the second tuber 200, and then the plurality of tubers 200. The method may include sterilizing, with at least one pair of flames 152, the first tuber 200, the second tuber 200, and then the plurality of tubers 200. The method may include cooling the blade array 140, after cutting the first tuber 200, the second tuber 200, and the plurality of tubers 200. In addition, the method may include generating the flame 152 by igniting the flammable gas mixture of acetylene and compressed air.

[0029] It should be understood from the foregoing that, while particular aspects have been illustrated and described, various modifications can be made thereto without departing from the spirit and scope of the invention as will be apparent to those skilled in the art. Such changes and modifications are within the scope and teachings of this invention as defined in the claims appended hereto.

Claims

CLAIMS What is claimed is:

1 . A tuber seed cutter sterilization device configured to receive a flammable gas and sterilize a tuber seed cutter having at least one rotational blade and a tuber conveyer, the at least one rotational blade configured to rotate about a longitudinal axis of a rotational shaft, the tuber seed cutter sterilization device comprising: a fluid channel configured to receive the flammable gas at an inlet port and direct the flammable gas toward at least one pair of outlet ports, each pair of outlet ports positioned at opposite axial sides of the at least one rotational blade; wherein the flammable gas is configured to be ignited into a flame at each one of the pair of outlet ports and each flame at the pair of outlet ports is configured to heat opposite outer surfaces of the at least one rotational blade.

2. The tuber seed cutter sterilization device of claim 1 , wherein the flammable gas includes acetylene.

3. The tuber seed cutter sterilization device of claim 2, wherein the flammable gas includes compressed air.

4. The tuber seed cutter sterilization device of claim 3, wherein the acetylene to compressed air ratio is between 4 and 12.

5. The tuber seed cutter sterilization device of claim 1 , further including a heat shield positioned above the at least one rotational blade and configured to improve heat retention of the at least one rotational blade.

6. The tuber seed cutter sterilization device of claim 5, wherein the heat shield includes an exhaust vent.

7. The tuber seed cutter sterilization device of claim 1 , wherein the outer surfaces of the at least one rotational blade is substantially planar and perpendicular to the longitudinal axis and each of the pair of outlet ports is configured to emit the flammable gas parallel to the outer surfaces of the at least one rotational blade.

8. The tuber seed cutter sterilization device of claim 1 , wherein the outer surfaces of the at least one rotational blade is substantially planar and perpendicular to the longitudinal axis and each of the pair of outlet ports is configured to emit the flammable gas at a nonparallel angle to the outer surfaces of the at least one rotational blade.

9. The tuber seed cutter sterilization device of claim 1 , wherein during rotation of the at least one rotational blade, the opposite outer surfaces of the at least one rotational blade are configured to rotate against the respective flames and have a dwell time against the respective flames between 0.004 seconds and 0.016 seconds.

10. The tuber seed cutter sterilization device of claim 1 , wherein during rotation of the at least one rotational blade, the opposite outer surfaces of the at least one rotational blade are configured to rotate against the respective flames and each flame is configured to heat a portion of the respective opposite outer surface to a temperature between 350° F and 500° F and the portion of the respective outer surface is configured to cool to a temperature between 220° F and 280° F before rotating against the respective flame again.

11. A tuber seed cutter assembly configured to receive a flammable gas, the tuber seed cutter device comprising: at least one rotational blade configured to cut a tuber into a tuber seed, the at least one rotational blade configured to rotate about a longitudinal axis of a rotational shaft; a conveyor configured to convey the tuber to the at least one rotational blade; and a fluid channel configured to receive the flammable gas at an inlet port and direct the flammable gas toward at least one pair of outlet ports, each pair of outlet ports positioned at opposite axial sides of the at least one rotational blade; wherein the flammable gas is configured to be ignited into a flame at each one of the pair of outlet ports and each flame at the pair of outlet ports is configured to heat the opposite axial sides of the at least one rotational blade.

12. The tuber seed cutter assembly of claim 11 , wherein the flammable gas includes acetylene.

13. The tuber seed cutter assembly of claim 12, wherein the flammable gas includes compressed air.

14. The tuber seed cutter assembly of claim 13, wherein the acetylene to compressed air ratio is between 4 and 12.

15. The tuber seed cutter assembly of claim 11 , further including a heat shield positioned above the at least one rotational blade and configured to improve heat retention of the at least one rotational blade.

16. The tuber seed cutter assembly of claim 15, wherein the heat shield includes an exhaust vent.

17. The tuber seed cutter assembly of claim 11 , wherein the outer surfaces of the at least one rotational blade is substantially planar and perpendicular to the longitudinal axis and each of the pair of outlet ports is configured to emit the flammable gas parallel to the outer surfaces of the at least one rotational blade.

18. The tuber seed cutter assembly of claim 11 , wherein the outer surfaces of the at least one rotational blade is substantially planar and perpendicular to the longitudinal axis and each of the pair of outlet ports is configured to emit the flammable gas at a nonparallel angle to the outer surfaces of the at least one rotational blade.

19. The tuber seed cutter sterilization device of claim 11 , wherein during rotation of the at least one rotational blade, the opposite outer surfaces of the at least one rotational blade are configured to rotate against the respective flames and have a dwell time against the respective flames between 0.004 seconds and 0.016 seconds.

20. The tuber seed cutter sterilization device of claim 11 , wherein during rotation of the at least one rotational blade, the opposite outer surfaces of the at least one rotational blade are configured to rotate against the respective flames and each flame is configured to heat a portion of the respective opposite outer surface to a temperature between 350° F and 500° F and the portion of the respective outer surface is configured to cool to a temperature between 220° F and 280° F before rotating against the respective flame again.

21 . A method for cutting a tuber seed with a tuber seed cutting assembly, the method comprising: conveying, with a conveyor, a first tuber to at least one rotational blade; cutting, with the at least one rotational blade, the first tuber into a first tuber seed; and sterilizing, with at least one pair of flames, the at least one rotational blade by simultaneous heating opposite surfaces of the at least one rotational blade with respective oppositely positioned flames of the at least one pair of flames.

22. The method of claim 21 , further comprising: rotating the opposite outer surfaces of the at least one rotational blade against the respective flames such that the opposite outer surfaces have a dwell time against the respective flames between 0.004 seconds and 0.016 seconds; heating a portion of the opposite outer surfaces against the respective flames to a temperature between 350° F and 500° F; and cooling the portion of the opposite outer surfaces to a temperature between 220° F and 280° F before rotating the portion of the opposite outer surfaces against the respective flames again.

23. The method of claim 21 , further comprising generating the flame, by igniting a flammable gas mixture of at least acetylene and compressed air.

24. The method of claim 23, wherein the acetylene to compressed air ratio is between 4 and 12.