In the case of a -sided laser tube , the front angle will vary as the beam moves in from the edge of the tube and this will be the of the tube. The depth to be cut just the beam into the core of the tube. This will on tube and wall . The front angle will , and at some point will reach the angle and move above this value. will thus vary of the in front angle. This will the speed of a -sided laser tube , and is in the in 6.
Once the laser beam into the core of the tube, where the melt from the kerf , a in also take place, due to a in the front angle, which is to the depth of being cut. This can be in the in 6. The cut in the upper of the tube to and at a the front angle will match the angle, where the laser (aided by the high gas ) in an . The of this point of will on the tube and the wall , as can be seen by the in 4 and 6.
the 1kW SM and MM for the MM laser beam below a gas of 6bar. It is that the of the gas jet and the beam of the MM (for all the tube) plays a role. A laser beam on the will the kerf width, which will allow the lower half of the tube to be more by gas mass flow-rate. A gas than 6bar may in gas jet , which could be to the kerf width by the 1kW SM laser beam and help to flush away the from the lower half of the tube. A gas , with air (20%) may also lead to in the kerf width, which when with laser , might the in speed seen with the SM . The best with the SM laser was with a of 8bar, at the two stand-off . gas at high with can jets with shock . , below or above the can in an under or over- gas jet, with shock and . This can a on the gas on the , which can the melt the kerf.
, a in speed for the SM laser at 10bar was . This may be due to the under- gas jet with kerf size. As , a kerf size would allow mass flow-rate the of the tube but a kerf, at a and gas , may flow . A flow could in a in the flow , which is most to re- , the half of the tube. Under these the gas flow will be the same as the , ie to the kerf. Such a would a of due to laser from the top of the cut onto the half of the tube, in to the path of un- , which would then laser power to re-melt.
The in the of the two beams could also play a role on the , at the tube edges with to the of the cut front angle and laser . A lower beam would a front angle, and this with near the tube edges, will in lower of the SM laser beam. , with the low of the SM laser, the power the is than that from the MM laser, which for lower laser . When with the kerf width with the SM , the of the gas jet very . This the lower seen below 6bar and the at 10bar. , use of a SM for may not be a real , due to on the fibre (max 5m) for the SM.
A very and for of steel tube has been . The head, for this , is light and has a and so is to and . For all tubes of and wall , the most are the tube sides, which both high laser power and gas , for clean . As a , a pass was to a pass as the . Even using the pass , the cut at the tube edges and the lower , was worse than at the top of the tube, and the cut also with an in the tube wall , for a . and multi-mode the of the gas jet to be more than the of the laser beam and that in -sided laser tube a kerf width is very .
Their to the in (UK) for of this . They also would like to thank Ltd for their and in this .
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