Application Of Laser Cleaning in Bridge U-Rib Cleaning
Jan 26, 2024
With the development of bridges in the world and the advancement of steel structure technology, steel structures are increasingly used in long-span bridges. Orthotropic plates have been widely used in the construction of steel structure bridges due to their advantages such as light weight and large load-bearing capacity. Applications.
The orthotropic bridge deck is mainly composed of a steel structure panel and cross beams and longitudinal ribs welded to it. The cross beams are mainly transverse partitions, and the longitudinal ribs are mainly U-shaped rib structures. Because U-shaped ribs can provide greater torsional stiffness and bending stiffness and can improve the stress state of the entire bridge deck, they have become the most commonly used cross-sectional form of modern orthotropic bridge decks.
As the span of steel bridges increases, steel bridge manufacturing puts forward higher requirements for the strength of materials and the bonding performance of welds and base metals. In order to ensure the welding quality of the orthotropic plate unit, the weld bead area of the U rib needs to be cleaned before welding to the panel to remove floating rust, scale, paint, oil and other attachments on the surface.
Traditional sanding method:
Manual Sanding:
Sanding operations are performed by manually operating various electric and pneumatic tools. During this process, the workpiece needs to be turned over repeatedly. The labor intensity of the workers is extremely high, and the sanding quality is unstable and the work efficiency is low. At the same time, the dust and noise generated by sanding will directly Threaten workers' health.
Mechanical Sanding:
Inevitably brings mechanical vibration and noise, leading to unstable grinding results, easy damage to workpieces, serious noise pollution, poor equipment stability and many other problems. In addition, the existing traditional U-rib sanding equipment requires manual assistance to position the area to be sanded on the U-rib before grinding. It cannot adaptively adjust according to the differences in the shape and size of the U-rib, and its scope of application is limited.
Whether it is manual or mechanical sanding, there is a common problem: the cleanliness is not up to standard.
A bridge weighing hundreds of thousands of tons requires at least millions of U-rib plate units, which are equivalent to the "skeleton" of the bridge. The cleaning quality of the U-rib parts to be welded plays a key role in the subsequent processing link - the welding quality of the orthotropic bridge deck. It is also an important factor affecting the service life, safety, wind resistance and earthquake resistance of the bridge.
U-Rib Laser Cleaning Solution
1. Comparing with international standards, it is as bright as new.
After the primer, floating rust, etc. of the parts to be welded on the U-rib are cleaned without media by laser, the cleaning level can reach the international general rust removal standard SA3 level, restoring the true color of the metal without causing damage to the base material. The U-rib weld bead after cleaning It not only has a beautiful appearance, but also has better surface consistency, which can effectively improve the welding quality of orthotropic bridge decks.
2. Silent and environmentally friendly, reducing smoke and dust.
The maximum air suction volume of the smoke and dust purification system is 10,000m³/h. The cleaning residue can be recovered through a vacuum cleaner, and the dust collection efficiency can reach 99.9%. In addition, compared with traditional cleaning methods such as manual grinding and mechanical grinding, laser cleaning does not produce waste gas or noise. The production noise at the customer's site has been reduced from 120 decibels in the past to less than 75 decibels, which greatly reduces the harm to the human body. It also improves the workshop production environment.
3. One-time investment is cost-effective.
Compared with mechanical cleaning, laser cleaning equipment requires a larger initial investment, but its subsequent maintenance costs are low. It can save 20% of labor (one piece of equipment can be operated by one person) and reduce energy consumption by 57%.
