Nowadays, landscape boulders play a vital role in urban construction. Since stone sculpture are often placed outdoors, some damage will inevitably occur. Let`s take a look at the solutions to different types of damage to outdoor stone sculpture.
1. Welding arc marks: When the welder strikes the arc on the metal surface, it will cause surface roughness defects. The protective film is damaged, leaving a potential source of corrosion. The welder should strike the arc on the already welded bead or on the side of the weld joint. The pilot arc trace is then melted into the weld.
2. Rust spots: Sometimes you will see rust on
stone carving products or equipment before or during the production process, which indicates that the surface is seriously contaminated. Rust must be removed before equipment is put into service, and thoroughly cleaned surfaces should be inspected by an iron test and/or a water test.
3. Welding defects: Welding defects such as: undercut, incomplete welding, dense pores and cracks not only reduce the firmness of the joint, but also become a source of crevice corrosion. When cleaning operations are performed to improve this outcome, they can also entrain solid particles. These defects can be repaired by re-welding or grinding and re-welding.
4. Scratches: In order to prevent the accumulation of process lubricants or products and/or dirt, scratches and other rough surfaces must be mechanically cleaned (such as dry sandblasting, abrasive glass beads).
5. Oil and grease: Organic substances such as oil, grease and even fingerprints can become sources of local corrosion. Because these substances act as a barrier, they interfere with chemical and electrochemical cleaning and must be completely removed.
6. Paint, Chalk and Markers: The effects of these pollutants are similar to those of oil and grease. It is recommended to wash with a clean brush and clean water or alkaline cleaning agent. You can also use high-pressure water or steam cleaning.
7. Flux: Welding processes using flux include manual welding, flux cored arc welding and submerged arc welding. These welding processes will leave small flux particles on the surface, which cannot be removed by ordinary cleaning methods. These particles will be the source of crevice corrosion, and mechanical cleaning methods must be used to remove these residual fluxes.
8. Thermal tempering color and other oxide layers: Thermal tempering color is caused by staying at high temperature or staying at a higher temperature for a long time. When any of these oxide layers appear, the chromium content of the metal surface is reduced, causing these areas to be less corrosion-resistant. In this case, not only should the thermal temper color and other oxide layers be eliminated, but the chromium-poor metal layer beneath them should also be cleaned.
9. Dust: Stone carving production is often carried out in places with dust. There is often a lot of dust in the air, which constantly falls on the surface of the equipment. They can be removed with water or alkaline solutions. However, adherent dirt requires high-pressure water or steam to clean.
10. Residual adhesive: When the tape and protective paper are removed, part of the adhesive will always remain on the surface of the stone sculpture. If the adhesive is not hard yet, it can be removed with an organic solvent. However, when exposed to light or air, the adhesive hardens, forming a source of crevice corrosion. Mechanical cleaning with fine abrasives is then required.
