Difficulties in ship cutting
The shipbuilding industry has high requirements for the accuracy of hull segmentation and transfer, and the clearance of frame transfer must be controlled within a range of 1mm. In the past, shipbuilding enterprises generally used plasma to cut the rib plates. In order to ensure assembly clearance, repair allowances were set on the rib plates, which required manual repair during on-site assembly. The quality of the repair was uneven, with residual oxides in the cut joints. At the same time, it increased the amount of assembly work and increased the assembly cycle, resulting in an extension of the entire segmented construction cycle. In addition, by using laser cutting machines to cut materials and eliminate assembly allowances, the phenomenon of on-site repair and cutting is eliminated, reducing labor and material waste. The assembly speed of the framework is significantly accelerated, and the assembly quality is significantly improved.
Advantages of laser cutting
The application advantages of laser cutting technology in shipbuilding In recent years, “precision shipbuilding” and “rapid shipbuilding” have become the main trends in the development of the shipbuilding industry. Laser cutting technology has developed rapidly, accounting for more than 70% of the entire laser processing industry.The shipbuilding industry mainly relies on steel plate raw materials and uses laser cutting to replace some punching and cutting methods that require complex and large molds, greatly reducing production cycles and costs.
At present, the shipbuilding industry mainly uses flame cutting, plasma cutting, shearing processing, and laser cutting for the cutting of ship hull sheet parts. Other cutting methods have many shortcomings compared to laser cutting, such as flame cutting and plasma cutting with wide cutting gaps, poor cutting accuracy, easy generation of harmful gases, and significant environmental pollution. For ship plate cutting, laser cutting has the advantages of high cutting accuracy, small thermal deformation, reduced secondary processing (such as milling edges, drilling, etc.), transportation, polishing, especially small circles, small holes, curved surface processing, etc. It meets the accuracy requirements of ship segmentation and matching, and can fully ensure that the assembly gap of the structure is controlled within the range of 1mm. However, its practical cutting speed in steel is relatively poor compared to plasma cutting. The relationship between cutting speed and cutting thickness of low-carbon steel under different cutting methods, and the cutting effect of low-carbon steel varies under different cutting methods. In the field of shipbuilding, laser cutting avoids the occurrence of uneven cutting quality when plasma is used to cut the rib plates. In order to ensure assembly clearance, cutting allowances are set on the rib plates and manually cut them. So as to reduce the workload, assembly cycle, material and labor cost waste of assembly.
Summary
The ship steel plate cut by laser has good cutting quality, good perpendicularity of the cutting surface, no slag hanging, thin oxide layer, smooth surface, no need for secondary processing, can be directly welded, and has small thermal deformation. The curve cutting accuracy is high, reducing working hours and achieving barrier free cutting of high-strength ship plates.