Steel structure is widely used in our lives, steel structure workshop, steel structure roof, color steel tile roof, etc. Long-term use of steel structure will cause corrosion and rust, how to remove rust from steel beams, this article tells you a few methods.
Causes of rust in steel structures
Rusting of steel structures is caused by oxidation, which may occur in both the external environment and internal materials. This results in rusted steel beams.
Steel structure corrosion range
Large steel structures such as lightning rod towers, offshore lighthouses, large reservoir gates, water supply towers, offshore oil production facilities, tank trucks, spherical tanks, storage tanks, fuel tanks, carbonization towers, heat exchangers, chimneys, containers, ship hulls, offshore platform steel Structures, etc., most of them have been exposed to the corrosive environment of marine atmosphere and industrial atmosphere for a long time.
The rust phenomenon of steel structures:
Mild rust: Pitting corrosion occurs on the surface, and some oxide scales appear.
Moderate rust: The red rust spot is obvious, and part of the oxide skin is cracked.
Severe rust: The oxide skin falls off, and there will be a protruding oxide layer. Some thick oxide layers cause the surface of the steel structure to sag.
Three major hazards caused by rust in steel structures:
- This results in a reduction in bearing capacity and affects structural stability.
- Leading to increased maintenance costs.
- Resulting in shortened
If the steel structure is not regularly maintained in a timely manner, rust spots and oxide scales will increase the rate of corrosion and rust of the steel structure, which will not only affect the service life of the steel structure, but also cause safety hazards.
Fastest way to remove rust from metal
The high-energy heat generated by the laser is used to volatilize the rust and oxides on the surface of the steel structure, thereby achieving the effect of rust removal.
Shot blasting and rust removal
The high-speed operation of mechanical equipment is used to eject steel shot of a certain size through the centrifugal force of the nozzle, causing the steel shot to collide violently with the parts, grinding rust off metal. In order to make the steel surface rust-proof, it uses two types of steel shot: cast iron shot and cut steel wire shot.
Sand blasting and rust removal
This method uses high-pressure air to blow out steel shot and spray it on the surface of the part to achieve rust removal. You can also use high-pressure air to bring out the quartz sand and spray it on the surface of the parts.
Pickling and rust removal
Also known as chemical rust removal. The principle is to use the acid in the pickling solution to chemically react with metal oxides to dissolve the metal oxides and remove rust and dirt on the steel surface. But pickling cannot achieve the surface roughness effect of shot blasting or shot peening. After pickling and rust removal, it must be cleaned and passivated with plenty of water. The large amount of waste water, waste acid and acid mist it generates will pollute the environment. If not handled properly, it will cause excessive corrosion on the metal surface and form pitting corrosion. Currently rarely used.
Manual and electric rust removal
The tools are simple and the construction is convenient. However, the labor intensity is high and the quality of rust removal is poor. This method can only be used partially when other methods are not available, such as refurbishment of individual components or partial descaling at the installation site.