Degreasing method (SSPC-SP1) polluted surface grease can be removed by the following methods, including: solvent cleaning method steam cleaning method alkali cleaning method cleaning detergent/water cleaning method solvent cleaning method solvent cleaning method is the most important method to remove surface grease. Some solvent paints can dissolve thin surface grease deposits, allowing them to mix with the paint without any adverse effects. However, it is not suitable for heavy grease deposition or water-containing coatings and solvent-free coatings. Solvent cleaning is generally used with rags, once dirty can be frequently replaced. The final wash is usually done with a new solvent, such as naphtha. No contact with eyes or skin, no spark or open flame nearby, and no unnecessary inhalation of organic solvents. The metal after solvent cleaning generally needs to be cleaned again before painting. Steam cleaning Steam cleaning is another effective method of removing grease. Commercial cleaners can be added to the steam to improve cleaning capacity. In addition, steam cleaning can also remove dust and dirt from the surface after painting. Steam - cleaned steel structures are required to be cleaned again by other means before coating. Alkali cleaning method Alkali cleaning method by wetting, emulsifying, dispersing grease to achieve effective cleaning purpose. This method may react with metals such as aluminum or zinc or wood or concrete.

Hand Tools Cleaning Method (SSPC-SP2) Hand tools remove only loose paint, rust, and oxide skin. Hand tools are inefficient and therefore most commonly used for small areas of cleaning. Hand tools include scrapers, wire brushes, and sanders. Power Tools Cleaning Method (SSPC-SP3) Power tools (electric and pneumatic) are designed to replicate the power drive of hand tools for faster cleaning capabilities. What's included: sander, grinder, metal brush, chisel hammer, descaler and needle gun. Some tools have vacuum tube connections that help reduce air pollution and recover debris from cleaning processes. Power tools are used by pounding or grinding or both. The power tool cleaning method is much cheaper than the hand tool cleaning method, and the sand blasting process will produce much less pollution to the environment particles. Therefore, hand tools are only recommended to be used in small areas or damage repair, and are not suitable for large areas of contaminants, especially if the use of surface tolerant oil-based paint is not recommended. Misuse of power cleaning tools can also smooth the surface of the gold instead of forming a roughness that is not conducive to coating adhesion.

Water cleaning and water spraying are used to clean metal and concrete surfaces. The Low Pressure Water cleaning method (LPWC) requires a pressure of 500OPSI. For better cleaning, the water can be heated and a cleaner added. Sometimes called power cleaning, LPWC is ideal for removing surface dust and visible mold without damaging surrounding woodwork and concrete/brick buildings. High Pressure Water Cleaning (HPWC) requires pressure between 5,000 and 10,000 psi. High pressure water injection (HPWJ) pressure requirements range from 10,000 to 25,000. Some believe that a pressure of 30, 000PSI should be cut off. For pressure exceeding this limit, called ultra high pressure water injection method (UHPWJ). The advantage of the water cleaning method over the sand blasting method is that it can remove the soluble salts that will cause the coating to bubble osmotically. In all water cleaning methods, corrosion inhibitors are often required to prevent flash corrosion of steel, but for some protective coatings, they are not required. Environmentally acceptable inhibitors include: sodium, phosphate.

Recommended cleaning methods for metals 

Different metals have their own best surface treatment, depending on the hardness of the metal. The most effective way to clean uncoated steel is to use solvent cleaning or steam cleaning after sandblasting. In fact, the SSPC standard requires solvent cleaning before hand and power tools are cleaned and sandblasted. Sand blasting is recommended for cleaning the damaged area. Water jet and water sandblasting are also good options, especially in areas where dry sandblasting is not acceptable. Other methods, such as manual or power tool cleaning, are more suitable for a small range of repairs. Due to different surface conditions, the recommended cleaning methods for uncoated galvanized steel vary. A simple solvent cleaning of the new clean galvanized sheet is sufficient to remove any protective oils used for outdoor storage of the galvanized sheet. Other temporary protective measures such as chromate treatment must be removed using the manufacturer's recommended method. Epoxy and latex coatings have no roughness requirements and can be tightly bonded to smooth, clean galvanized surfaces, but some builders consider phosphoric acid or other chemical treatments necessary. New and clean aluminum and other soft metals can be cleaned adequately with solvent cleaning. Dust and loose corrosion can be removed by cleaning agents: Old paint can be removed with plastic particles or other light sandblasting methods whereas sandblasting with coarse particles (steel balls or pellets) can damage soft metal surfaces. These metal surfaces can be cleaned first to increase adhesion to oil-based or latex paints. Low alloy steel generally does not need to be protected by coating, but depends on the natural oxide film formed. If it is necessary to remove the invisible rust spots for painting, high pressure or ultra-high pressure water injection method is needed. In order to achieve surface roughness, sand blasting particles are also required. The coating system usually used in steel structure is generally adopted. The purpose of stainless steel coating is for satisfactory appearance. In order to make the primer and stainless steel or other hard metal adhesion, the need for sufficient roughness, usually with hard non-iron sandblasting particles, such as alumina, garnet, emery.