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With the development of the times, shipbuilding technology has been continuously improved, and shipbuilding materials and ship design have also undergone changes over time. The "Medium and Long-term Development Plan for the Shipbuilding Industry" approved and released by the State Council clearly sets out the guiding principles and development goals of the industry. The guiding principles are to deepen reforms, accelerate development, and adhere to a new path of industrialization; improve independent research and development capabilities and ship equipment supporting capabilities, enhance the core competitiveness of the shipbuilding industry; "introduce" and "go global" simultaneously, shipbuilding enterprises should focus on introducing and digesting modular outfitting, efficient welding, cutting, and other key shipbuilding construction technologies and modern shipbuilding production management technologies.

Laser cutting technology has been continuously developed and progressed with the advancement of the times, and laser power has also increased from the initial 500W, 1kW to the current 30kW and 40kW. The reason why laser cutting can develop vigorously is that it has advantages that traditional cutting cannot replace, such as good cutting quality, fast cutting speed, safety and pollution-free, and a wide variety of materials that can be cut. It is usually applied to various industries such as aerospace, shipbuilding, furniture decoration, medical equipment, agricultural machinery, and the automotive industry.

As an advanced welding technology, laser welding has the advantages of high welding efficiency, good welding quality, and less consumption of welding materials. For medium-thick plates, laser-arc hybrid welding, as an advanced welding technology at present, is being applied to industries such as aerospace, rail transportation, construction machinery, and steel structures.

As a new metal surface treatment technology, laser cleaning is also gradually being applied to industrial production. Laser cleaning can remove paint, rust, pre-welding metal oxide film, post-welding oxide layer, and other contaminants on the metal surface.

As the initiator of the "Key Technology and Equipment for Laser-Arc Hybrid Welding of Medium-Thick Plates" under the Zhejiang Province Vanguard Plan research and development project, Penta Laser proposes a comprehensive solution for efficient cutting and welding in the shipbuilding industry.

1.Overall solution of laser cutting and welding in shipbuilding

Penta Laser combines the usage of laser-arc hybrid welding in foreign shipyards such as Meyer Werft and Blohm+Voss, as well as domestic shipyards like CIMC Raffles, to propose this overall solution. The overall solution adopts a pipeline operation, including modules for material processing, laser cutting of ship plates, T-beam and web plate laser cutting, laser-arc welding of ship plate components, laser-arc hybrid welding of T-beams, and laser-arc hybrid corner welding of ship plates and T-beams.

1.1 Material processing module

The material processing module includes an automated system for "incoming material-decontamination-shot blasting-alignment-coating-conveyance" of the plates. This module is designed with automation, allowing the plates to move on the assembly line for pre-processing. It reduces the need for lifting and transporting the plates, saving manpower and resources.

1.2 Ship plate laser cutting module

The shipbuilding industry mainly uses steel plates, and the cutting needs primarily come from ship plates and T-beam components. This solution adopts Penta's BULL series large-format laser cutting machine, which can expand the cutting range up to 20 meters in width and 60 meters in length, meeting the majority of plate cutting requirements.

The steel plates obtained through laser cutting have good cutting seam quality, good perpendicularity of the cut surface, no slag hanging, thin oxide layer, smooth surface, and no need for secondary processing. They can be directly welded with minimal thermal deformation. The high precision of curve cutting reduces fitting time and achieves obstacle-free cutting of precision ship plates.

In addition, laser cutting machines have significant advantages in processing medium-thick plates. The cutting speed is faster compared to traditional plasma cutting, and as the power increases, the cutting speed of carbon steel plates ranging from 10mm to 50mm will continuously increase. Similarly, as the power increases, the maximum cutting thickness of carbon steel plates also increases.

1.3 Ship plate laser arc compound welding module

Traditional ship plate welding generally uses gas shielded welding and submerged arc welding methods. For thicker plates, beveling is required, and multi-layer and multi-pass welding is performed. For certain positions of the ship plate, due to its thickness, it needs to be flipped after the front-side welding is completed. The manufacturing process is cumbersome and requires a large amount of manpower and resources.

For laser arc compound welding, single-side welding and double-side forming can be achieved without beveling the thick plate. The welding speed can generally reach 1.2m/min or even higher, and the welding efficiency is 5-8 times that of traditional welding methods. After welding, the plate has better forming effect and does not require secondary processing of the weld seam.

In the ship plate laser arc compound welding module, TAN Laser has proposed a solution for large-scale dual gantry laser arc compound welding. The dual gantry serves as the motion mechanism of the compound welding head and also acts as a fixture carrier. At the center position of the dual gantry, a disc milling cutter is installed to perform end-face machining on the transported ship plate, preventing the cutting oxide layer from contaminating the weld pool and affecting the welding quality.

At the same time, a laser cleaning head is installed in front of the laser compound welding head to remove surface paint at the joint position, preventing the paint from affecting the welding process.

1.4 T Beam laser arc compound welding module

Traditional T Beam welding usually uses a combination welding and correction machine, with submerged arc or dual shield welding as the heat source. The welding speed is generally 0.3-0.5m/min, requiring simultaneous welding on both sides. It also consumes a large amount of welding wire and flux. The finished T-beam often experiences significant deformation, with low correction efficiency.

Based on this working condition, TAN Laser has developed a specialized machine for T Beam laser arc compound welding. The main structure of this machine is similar to that of traditional combination angle welding machines. It utilizes dual heat sources of laser and arc. The dual heat sources can improve welding efficiency and reduce heat input to the weld seam.

1.5 Ship plate and T Beam laser arc compound welding module Traditional ship plate and T Beam angle welding methods involve manual pairing, spot welding, and continuous welding using a cart. Compared to advanced welding technologies abroad, this production mode is outdated, resulting in large welding deformations and low production efficiency.

In response to this, TAN Laser has proposed a ship plate and T Beam laser arc compound angle welding solution. This solution utilizes dual heat sources of laser and arc. The laser is incident at a small angle on the weld seam between the ship plate and T Beam. The completed weld seam achieves single-side welding with double-sided forming. Compared to traditional cart-based arc welding, this method improves production efficiency by 5-8 times and reduces welding material consumption by more than 3 times, making it the best alternative to traditional welding methods.

In conclusion, TAN Laser can provide a complete solution from material cutting to welding and assembly. As a foreign-controlled enterprise, TAN Laser's technology is international, while its equipment is domestically produced, and its services are localized. The increasingly fierce competition drives the market to demand improvements in shipbuilding intelligent manufacturing processes, shipbuilding material safety, reliability, and quality. Traditional cutting and welding technologies in shipbuilding will inevitably be replaced by new technologies. Laser is known as the "fastest knife," the "most precise ruler," and the "brightest light." Due to its high precision and efficiency, laser technology will undoubtedly play a crucial role in the intelligent manufacturing process of shipbuilding, whether it is for flat cutting or welding.

2. Application of Laser Cleaning Technology in Shipbuilding and Repair

Laser cleaning technology is a highly promising and important technique that is gradually changing industrial environmental protection. In recent years, China has increasingly strict environmental protection policies, leading to rapid growth in the demand for laser cleaning in the market.

Laser cleaning is the process of removing material from a solid (or sometimes liquid) surface by irradiating it with a laser beam. At low laser flux, the absorbed laser energy heats the material and causes it to evaporate or sublime. At high laser flux, the material typically converts into plasma.

Compared to traditional cleaning methods such as mechanical friction cleaning, chemical corrosion cleaning, liquid-solid powerful impact cleaning, and high-frequency ultrasonic cleaning, laser cleaning has significant advantages:

Laser cleaning is a green cleaning method that does not require the use of any chemical agents or cleaning liquids. The waste generated from laser cleaning is primarily solid powder, which has a small volume, is easy to store, and can be recycled, effectively addressing the environmental pollution caused by chemical cleaning.

Traditional cleaning methods often involve contact cleaning, which applies mechanical forces to the surface of the object being cleaned, causing damage to the surface or leaving cleaning media attached to the surface, resulting in secondary pollution. Laser cleaning solves these problems through its non-abrasive and non-contact nature.

Laser can be transmitted through optical fibers and combined with robotic systems, enabling convenient long-distance operations and allowing cleaning of areas that are difficult to reach using traditional methods. This ensures the safety of personnel, especially in hazardous environments.

Laser cleaning can remove various types of contaminants from the surfaces of different materials, achieving cleanliness that conventional cleaning methods cannot achieve. It can also selectively clean specific pollutants on the material surface without damaging the underlying material.

Laser cleaning is highly efficient and saves time.

In the shipbuilding and repair process, there is often a need for large-scale rust removal and paint stripping on steel surfaces. Laser cleaning, with its processing advantages, can replace traditional methods such as mechanical polishing or water sandblasting. By adjusting parameters such as laser power and frequency, the desired cleaning points can be effectively removed while protecting the base material from laser damage. The scanning width can be adjusted according to the cleaning surface, ensuring the accuracy of the cleaning area. Additionally, laser, as a clean energy source, can effectively prevent occupational diseases among workers, and efficient dust removal measures can minimize pollution.

Overall, laser cleaning technology offers numerous advantages and is a highly effective and efficient solution for various cleaning needs in shipbuilding and repair processes.

3. Summary

Mechanization, automation, and laser welding are major trends in the shipbuilding industry, and with the development of laser welding technology and increasing information exchange, this trend will become more and more prominent. Since 2018, Penta Laser has invested a significant amount of manpower and resources in 3D laser cutting, welding, laser tube cutting, and large-scale cutting machines, achieving noticeable results. The products have matured and are being installed in batches in the market. In particular, in the field of laser welding, the company has hired technical experts from Germany and Italy, enabling us to enhance our welding technology to a leading level in China. From 2019, Penta Laser has steadily produced handheld laser welding equipment, with over a thousand units applied and exported to international markets.

We are constantly innovating to provide the highest quality and efficient solutions for global industry needs.