A Study on Laser Cleaning Efficiency of Epoxy Paint According to Process Parameters (I) - The Effect According to The Laser Beam Overlap Rate -

2020 ◽  
Vol 44 (3) ◽  
pp. 199-205
Author(s):  
Jong-Do Kim ◽  
Ji-Eon Kim ◽  
Moo-Keun Song ◽  
Jong-Myoung Lee ◽  
Myoung-Soo Han
Photonics ◽  
2020 ◽  
Vol 7 (4) ◽  
pp. 130
Author(s):  
Jiacheng Li ◽  
Haoting Liu ◽  
Limin Shi ◽  
Jinhui Lan

To improve the laser cleaning efficiency of Q235 carbon steel, an imaging analysis-based intelligent technique is proposed. Both offline and online computations are designed. Regarding the offline procedure, first, the corrosion images are accumulated to compute the gray-level co-occurrence matrix (GLCM) and the concave-convex region features. Second, different laser cleanings are performed to obtain various cleaned images. Third, a new cleaning performance evaluation method is developed: a metal color difference feature and a dynamic weight dispatch (DWD) corrosion texture are computed. Finally, a particle swarm optimization (PSO)-support vector machine (SVM) is utilized to forecast the laser process parameters. The corresponding laser parameters include power, linear velocity, and line spacing. For the online computation, after the GLCM and the concave-convex region features are computed, an iterative computation is used to tune the process parameters: the random laser parameters are generated constantly, and the iteration is performed and terminated only if the PSO-SVM output is positive. The experimental results have shown that the cleaning efficiency of this method can be improved, and the qualified rate is 92.5%.


Coatings ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1510
Author(s):  
Ji-Eon Kim ◽  
Jong-Myoung Lee ◽  
Jeong-Hun Hyun ◽  
Je-Han Jeong ◽  
Jong-Do Kim

Shipyards are very interested in improving their working environment and resolving environmental pollution issues by replacing mechanical cleaning technologies used before and after painting processes with laser cleaning technology. Because epoxy paint is thickly coated, with a thickness of 200 μm or greater, it is difficult to remove using both laser cleaning and mechanical cleaning technologies. Therefore, this study tried to obtain effective cleaning results by controlling the process parameters when removing the thick epoxy coating using a Q-switching fiber laser cleaning system with an average power of 100 W developed by our research team. The pulse duration time of the laser is 150 ns. Additionally, in order to determine whether the cleaning was sufficient, the difference in laser-induced plume/plasma was compared. By controlling the beam scanning patterns, line overlap rate, and pulse overlap rate, it was possible to obtain effective cleaning results without introducing removal deviation. In addition, the NOP increased when the laser beam overlap rate increased. This increased the amount of heat input to the material and reduced the number of scans required to remove the epoxy paint. As a result of the plume/plasma analysis, less plume/plasma was generated as the paint was removed if the epoxy paint remained on the surface. On the other hand, when all of the paint was removed, a higher brightness of plume/plasma generated by evaporation of the bare metal was observed.


2009 ◽  
Vol 45 (11) ◽  
pp. 553
Author(s):  
J.Y. Baek ◽  
H. Jeong ◽  
M.H. Lee ◽  
J.D. Song ◽  
S.B. Kim ◽  
...  

2020 ◽  
Vol 20 (2020) ◽  
pp. 229-230
Author(s):  
Jhonattan Gutjahr ◽  
Francisco Ratusznei ◽  
Thiago Soares Pereira ◽  
Alexandre Cunha ◽  
Santiago Javier Caraguay Correa ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document