Le Jia bathtub Guo Tong pipeline paint surface treatment

According to Party A's requirements, the surface treatment is carried out by sand blasting.

The derusting grade reaches Sa2.5, and all impurities such as grease, scale and rust on the metal surface are removed. Visible shadow stripes, spots and other residues shall not exceed 5% of the unit area.

There is no visible grease and dirt on the steel surface, and any residual traces of scale, rust, paint coating and other attachments should be spots or strip-shaped slight spots.

After derusting, the surface roughness of the base course should reach 40-65μm, which is suitable for the thickness of the primer of the anticorrosive paint.

Sandblasting: The compressed air used for surface treatment must have sufficient pressure and gas volume, and cannot contain oil and water.

Abrasive should be dry and free of oil, dust and other pollutants.

The recovered abrasive shall be clean, with proper sharp corners, free from corrosion and visible abrasive wear, and the hardness of the abrasive shall be 4 Mohs. Other shapes, relative density, bulk density and reuse should meet the requirements of the specification.

The sand blasting operation area shall not be close to the painting operation area to prevent the wet paint film from being polluted by dust and abrasive.

If the site conditions cannot distinguish the sand blasting operation area from the painting operation, the painting operation can only be carried out after the sand blasting operation is completed and the dust falls.

Before sandblasting, all welding protrusions, burrs and surface protrusions should be polished smooth and smooth, and all welding slag must be cleaned up.

After surface pretreatment, painting should be carried out immediately after inspection to avoid rust again.

If the surface has returned to rust, it should be sandblasted, and manual and mechanical derusting can be used to reach St3.