After a long period of use, the hull of a ship is prone to aging, corrosion, and other phenomena. Therefore, some processes are needed to renovate the hull. The traditional method is to use sandblasting technology for treatment. In recent years, the advantages of laser cleaning technology for ships have gradually become prominent.

The laser cleaning technology uses a high energy density laser beam as a processing tool. Its application in the marine field can not only obtain high-quality marine steel cleaning surfaces, but also greatly improve the quality of subsequent spraying, welding, and other processes. It has advantages such as more convenient operation, good localization, and green environmental protection. The laser cleaning technology for ships is easy to dry, realizing automation, integration, and intelligent cleaning of paint removal devices.

Analysis of limitations of traditional ship cleaning methods

Regular cleaning of rust and contaminants on the surface of workpieces used by ships has always been an important task in ship production and maintenance. Good ship cleaning is not only an important guarantee for high-quality ship manufacturing processes, but also very important for the safe operation and extended service life of ships. The traditional ship cleaning technology mainly relies on manual work. Sand blasting, polishing, high-pressure water flushing, and chemical cleaning not only have high labor intensity and serious pollution during the cleaning process, which is not conducive to the health of cleaning workers, but also easily cause damage to the ship itself.

With the continuous improvement of national environmental protection requirements and the continuous attention paid to the health and safety of construction personnel, traditional cleaning technologies have gradually been unable to adapt to the requirements of the new era of shipbuilding industry, and the demand for new cleaning technologies has become increasingly urgent.

Ship laser cleaning is an advanced new type of industrial cleaning technology that uses high-energy pulsed lasers to irradiate the surface of a workpiece that needs to be cleaned, causing rust, paint, and substrate on the surface of the workpiece to absorb pulsed lasers in a short period of time, causing a series of complex changes such as vibration, melting, and gasification from within, rapidly separating the contaminated layer from the substrate surface to achieve the goal of thorough laser cleaning and laser welding.

Advantages of laser cleaning of ships compared to traditional cleaning technologies

(1) Laser cleaning does not directly contact the workpiece to be cleaned, does not generate mechanical pressure, and does not cause damage to the workpiece;

(2) The directionality of the laser beam is flexible and controllable, and the size and size of the light spot can be adjusted to adapt to the fine cleaning of planar or replicated curved surface workpieces;

(3) The cleaning process is highly controllable and meets the cleaning needs of various types of pollutants;

(4) Laser can be transmitted through a beam of light, with high operational flexibility and easy to achieve remote control;

(5) Laser cleaning has a certain surface modification effect, which can effectively prevent secondary oxidation and improve surface mechanical properties;

(6) The laser cleaning process has low noise, no dust, chemical agents, and other pollution.

Therefore, laser cleaning has received extensive attention from technical personnel in the shipbuilding industry in recent years.

Application of laser cleaning in the field of ships

Cleaning is a very important processing and forming technology in the shipbuilding industry, and there is a large amount of cleaning work before and after welding and before coating. The quality of cleaning work also determines the quality of welding and coating to a certain extent. As a new cleaning technology, many scholars have tried to apply laser cleaning to welding.

Existing problems and countermeasures

Currently, the application of laser cleaning technology in the domestic shipbuilding industry is still relatively small, due to costs, efficiency, and process adaptability.

1. Equipment cost issues

Currently, the cost of laser cleaning machine is still high, with a total cost of about 200000 yuan for a 100W nanosecond laser cleaning equipment, while the cost of kilowatt level laser cleaning equipment has reached millions. Compared to traditional cleaning equipment (such as polishing tools, sandblasting equipment, etc.), this is a significant expense. Moreover, due to the energy loss and water cooling requirements of laser cleaning equipment during the electro-optical conversion process, the use cost of laser cleaning is also higher than that of traditional cleaning equipment. However, high cost does not bring significant improvement in cleaning efficiency. Even kilowatt level laser cleaning equipment still has lower cleaning efficiency than traditional sand blasting and high-pressure water washing processes. Cost and efficiency issues have seriously hindered the application of laser cleaning in the shipbuilding industry.

However, the cost of equipment is not fixed, while the hidden costs of traditional cleaning technologies are increasing. With the continuous progress of technology, the cost of laser cleaning equipment is continuously declining. The price of nanosecond laser cleaning equipment has dropped by nearly half in two years, and there is still much room for decline. However, there are many hidden costs such as grinding and sandblasting, and the costs are constantly increasing. For example, the state's requirements for environmental protection are constantly increasing, and the penalties for heavily polluting enterprises are also increasing. The environmental pollution of sandblasting operations in the shipbuilding industry is extremely serious. Due to the rapid damage of automation equipment in harsh working environments, sandblasting operations cannot even be automated. These not only greatly reduce the cleaning efficiency, but also seriously damage the health of construction personnel. However, as long as a small amount of smoke is generated during the cleaning process, laser cleaning can be quickly cleaned with a vacuum cleaner, and it will not cause damage to automated equipment. Therefore, laser cleaning is very suitable for automated operations. Automated operations can quickly narrow the gap between laser cleaning and sandblasting in terms of cost and cleaning efficiency. With technological progress, there may not be no possibility of anti-supersonic sandblasting technology in the future.

In addition, laser cleaning has shown great advantages in the application of special occasions in the shipbuilding industry. In the application research of laser cleaning, relevant technical personnel in the field of ships have found that laser cleaning is more efficient than traditional polishing techniques in cleaning grooves, weld bead surfaces, localized corrosion areas, and small internal spaces of ships. In some parts with high surface quality requirements, laser cleaning with no or very low damage has shown far more advantages than traditional cleaning techniques.

2. Process adaptability

There are various types of marine materials, and laser cleaning, as a new technology, is not yet comprehensive and in-depth in the process research of corresponding materials, and there is also a lack of corresponding specifications and standards. These are not conducive to the promotion of laser cleaning technology in the shipbuilding industry.

These problems have been greatly improved in recent years. Many technical personnel in the field of shipbuilding have gradually carried out research on the process and application of laser cleaning, and have also obtained a large amount of experimental data. It is believed that in the near future, these experimental data can form a corresponding process database to guide the application of laser cleaning in the shipbuilding industry.

To promote the application of laser cleaning in the shipbuilding industry, it is crucial to establish laser cleaning norms and standards for the shipbuilding industry, as industry norms and standards are guiding documents that guide the application of technology in relevant industries. The shipbuilding industry should promptly organize and integrate the research results of laser cleaning in its own industry, organize the establishment of corresponding industry norms and standards, so as to rapidly promote the application of laser cleaning in the shipbuilding industry.

Summary

As a new technology, laser cleaning may still have shortcomings in terms of cost, efficiency, and process, and it still needs some time to promote its application in the shipbuilding industry. The road is tortuous, but I believe that the future is bright.

The development and application of a promising new technology requires our joint efforts. I believe that in the near future, laser cleaning technology will occupy its own place in the field of ships, contributing to green ships.

About HGTECH: HGTECH is the pioneer and leader of laser industrial application in China, and the authoritative provider of global laser processing solutions. We have comprehensively arranged laser intelligent machine, measurement and automation production lines, and smart factory construction to provide overall solutions for intelligent manufacturing.