Seamless tubes (SMLS) are cut into sections by steel mills, and then heated in an annular furnace-perforated-sizing-straightening-cooling-cutting-packed to become qualified finished products, which generally cannot be placed in the production workshop of the user. With so many stocks in stock, dealers need to place some stocks. However, dealers generally do not have large indoor warehouses. If they do, the cost is too high and it is not cost-effective. Most of them are outdoor warehouses, and the seamless steel tubes will inevitably be exposed to wind and sun if they are placed outdoors.
The so-called floating rust, as the name implies, is a layer of rust floating on the seamless steel tube, which can be removed with a towel or other things. Simply speaking, the floating rust is considered to be no rust, which belongs to the normal state. The rust of seamless tubes is a long time. At least one year of seamless steel pipes that have been exposed to wind and sun outdoors. There are large and small hemp pits on the rusty seamless steel tubes. The single biggest difference in rust.
How to deal with the rusty seamless steel tube?
- Clean directly
If it is dust, oil and other substances, organic solvents can be used to clean the surface of the seamless steel tube. But this can only be used as an aid to other rust removal methods, and cannot directly remove rust, scale and other substances on the steel surface.
Generally, two methods of chemical and electrolytic pickling are used for pickling treatment. Cleaning with chemicals can remove scale, rust, old coatings, and sometimes it can be used as a retreatment after sandblasting and rust removal. Although chemical cleaning can effectively remove the rust on the seamless steel tube and make the surface of the steel pipe reach a certain degree of cleanliness and roughness, its shallow anchor pattern will cause serious environmental pollution.
3. Polishing and grinding
If there is a large area of rust, the foundry manufacturer can use professional tools to remove the rust, and use mechanized equipment to precisely polish the rust position. In addition to eliminating oxidizing substances, it can also make the seamless tube reach a smooth plane. Mainly use tools such as wire brushes to polish the surface of seamless steel tubes, which can remove loose or raised scale, rust, welding slag, etc. The rust removal by hand tools can reach Sa2 level, and the power tool rust removal can reach Sa3 level. If the surface of the seamless steel tube is attached with a firm oxide scale, the rust removal effect of the tool is not ideal, and the anchor pattern depth required for anti-corrosion construction cannot be reached.
4. Spray (throw) shot to remove rust
Spraying (throwing) rust removal is driven by a high-power motor to rotate the spraying (throwing) blades at high speed, so that steel sand, steel shots, iron wire segments, minerals and other abrasives are sprayed (throwing) on the surface of the steel tube under the action of centrifugal force , not only can completely remove rust, oxides and dirt, but also the seamless steel pipe can achieve the required uniform roughness under the action of violent impact and friction of abrasives.
Any rust removal method may cause large or small damage to the carbon steel seamless tube. Although effective rust removal methods can prolong the service life of carbon steel tubes, it is best to pay attention to the storage of seamless tubes from the beginning. Pay attention to the ventilation, temperature and humidity of the location, and follow the relevant storage standards, which can greatly reduce the possibility of rust on the seamless steel tube.