What is the difference between sandblasting and spray masking

       In order to avoid the influence of the surface roughening process on the non-coarsening surface, and to protect the non-spraying surface during the spraying process, it is convenient to clean the non-spraying surface after spraying, especially for various self-bonding powders. A coating can also be formed on the surface of the sandblasting and is not easy to remove, so masking treatment is required before sandblasting and spraying. According to the purpose of shielding protection, it can be divided into two kinds: rough shielding protection and spraying shielding protection.



Only silicone and Teflon (polytetrafluoroethylene) can be used both as a masking protection before roughening treatment and as a masking protection before spraying. However, during the thermal spraying process, special attention should be paid to keeping the surface of the part at a lower temperature, especially when silicone and Teflon (polytetrafluoroethylene) are used for masking protection, and the surface temperature of the substrate should be carefully controlled to prevent The shade can overheat and even burn, contaminating the coating. Materials suitable for pre-roughening masking protection are mainly fabrics, rubbers and plastics; materials suitable for pre-spraying masking protection are mainly metal or glass wool masking tapes, which can block spray particles from forming a coating on non-roughened surfaces, and When the non-sprayed surface is masked after spraying and before spraying, the following methods can also be used to complete the masking protection:



1) Use a protective cover, make a protective cover for the non-spraying parts in advance according to the characteristics of the parts, and use it before roughening and spraying.



2) Bundle thin copper or thin iron on non-sprayed parts.



3) Brush coating anti-sticking materials near the sprayed surface, such as Metco Anti-Bond (Metco Anti-Bond, Metco Masking Compound and Metco Super Spray Mask) and JPTK-1 type graphite produced by Tianjin Mechanical Coating Research Institute Anti-sticking agent. This method is especially suitable for complex or irregular surfaces.



4) Use wooden plugs, graphite rods or other heat-resistant non-metallic materials to block keyways, oil holes or threaded holes on the sprayed surface. The blocking block should be about 1.5mm higher than the surface of the substrate, so that it can be removed after spraying.