 |
|||||||||||
|
SYNRAD, INC. - http://www.synrad.com |
 |
||||||||||
|
|||||||||||
|
SYNRAD's sealed CO2 lasers are used in a variety of industrial processes including cutting, welding, drilling, and marking. This news brief showcases some of the interesting materials and products that are processed daily by Synrad's line of CO2 lasers and marking heads. |
|||||||||||
|
Type 304L stainless steel is a variation of 304 stainless, containing a maximum carbon content of 0.03%, which eliminates chromium carbide precipitation when exposed to the high temperatures inherent in welding operations. Carbide precipitation leads to localized corrosion and cracking, which is not desirable considering that 304L stainless tubing is frequently used in food preparation equipment and to transport solutions used in textile, pharmaceutical, and chemical processing industries. For this application, we were asked to laser cut Type 304L stainless tubing. Although this tubing will not be welded, it is subjected to other forming operations that could lead to stress cracking if the heat-affected zone (HAZ) in the cut region becomes too large. Our cutting setup consisted of a Firestar f400 laser delivering its beam through X-Y flying optics into a cutting head holding a 63.5 mm (2.5) positive meniscus lens. This lens provides a 100-micron (0.004) spot with a 1.8 mm (0.07) depth of focus. To enhance the laser cutting process, our gas assist consisted of 99.996% pure oxygen at a pressure of 5.5 bar (80 PSI).
|
|
||||||||||
|
For material handling, we held the 57.15 mm (2.25) diameter tubing in a rotary chuck turning at 20 RPM. At a power output of 400 watts, we were able to cut through the 1.27 mm (0.050) thick Type 304L tubing in one revolution, which translates to a linear cut speed of 3.56 meters per minute (140 inches/minute), in a cycle time of 3.03 seconds per part. As shown in the photograph, the cut edge is clean with no dross and a near non-existent HAZ region.
|
|||||||||||
|
Polypropylene (PP) piping is used in diverse fluid-handling installations ranging from potable water and purified water systems to acid waste and chemical systems. PP pipe is ideal for high temperature applications where polyethylene (PE) and PVC pipe are not rated for use. Extruded PP pipe is seamless and chemically inert. When multiple sections or branches of pipe are fusion welded together, the assembly becomes a continuous piece with a zero percent leakage rate. For this application, we were asked to mark manufacturing data on 2-inch nominal O.D. UV resistant polypropylene pipe. Our marking setup consisted of a Firestar t80 laser, FH Flyer marking head, and our WinMark Pro laser marking software. Because of the large mark required, we fitted the Flyer head with a 370 mm lens that provides a 540-micron (0.021) diameter spot over the extents of a mark field measuring 241 mm by 297 mm (9.5 x 11.7). |
|
||||||||||
|
The mark file covers an area measuring 19.1 mm by 292.1 mm (0.75 x 11.5) and consists of manufacturing data including company name and location (using a custom TrueTypeฎ font), logo, and patent/part numbers. The company name/location text object measures 14.2 mm (0.56) high while the smallest part number text measures 6.1 mm (0.24) high. The logo measures 19.3 mm high by 19.8 mm wide (0.76 x 0.78). At a power level of 80 watts, we achieved engraved marks with good contrast at a Velocity of 305 millimeters per second (12 inches/second) in a cycle time of 8.69 seconds per mark.
|
|||||||||||
|
Fluoropolymers are thermoplastic polymers where some or all of the hydrogen has been replaced by fluorine. These materials (TFE, PFA, PVDF, etc.) are resistant to high temperatures (including fire), chemicals, weathering, and abrasion. They also exhibit low coefficients of friction, high dielectric strength, and are chemically inert. Taken together, these properties define the ideal material for insulating electrical wire. The fluoropolymer connection to CO2 lasers is twofold: First, fluoropolymers are easily vaporized by the CO2 beam; and two, copper and aluminum wire are reflective at the 10.6 micron wavelength. Because the wire is not nicked or damaged by the laser beam, wire stripping remains an excellent CO2 application.
|
|
||||||||||
|
This article highlights a proof-of-concept test for stripping 10 AWG and 26 AWG fluoropolymer-coated wire. The demonstration setup consisted of a Firestar f201 (200 W) laser, an XY table for beam delivery, a 63.5 mm (2.5) focusing optic and clean, dry air assist at 0.34 bar (5 PSI). Our choice of optic provides a 100-micron (0.004) spot with a 1.8 mm (0.07) depth of focus. The 26 AWG wire, the smaller wire in the photo, has an 0.08 mm (0.003) thick insulation coating that we ablated at a speed of 22.9 meters per minute (900 inches/minute) using 50 watts of power. At the 100 W power level, we achieved a cut velocity of 50.8 meters/minute (2000 inches/minute). When stripping the 0.34 mm (0.0135) thick fluoropolymer coating from the 10 AWG (larger wire), we cut through the coating at a speed of 22.9 meters per minute (900 inches/minute) using 100 W and cut at a speed of 45.7 meters/minute (1800 inches/minute) using 200 W of power. In actual production circumstances, an integrated CO2 wire stripping machine would create a complete cut around the wire circumference so that the insulation is easily removed in preparation for termination or soldering. In specialized applications involving ribbon or multi-connector cable, the beam is scanned across the wire to strip selected conductors at predetermined points so that individual conductors are only connected to specific components along the wiring path.
|
|||||||||||
|
|
|||||||||||
|
Synrad, Inc. 4600 Campus Place Mukilteo, WA 98275 Tel: 1-425-349-3500 Fax: 1-425-349-3667 E-mail: synrad@synrad.com |
|||||||||||
| To unsubscribe, please click here. | |||||||||||
|
SYNRAD and Synrad product names are trademarks or registered trademarks of SYNRAD, Inc. All other trademarks or registered trademarks are the property of their respective owners. |
|||||||||||
