- Nov 22, 2017 -
Solvent inorganic zinc rich primer construction quality control includes both process control and quality detection, especially the process control in solvent inorganic zinc rich primer is more important to some construction applications.
The process control of construction quality
1 steel plate surface treatment before painting quality control
To check before coating steel plate edges arc, surface defect treatment, salt, oil cleaning whether meet the technological requirements.
2 spray steel shot derusting quality control
(1) spray steel shot derusting before to improve the quality of high pressure air and pressure testing, to ensure the high pressure air no oil, no water, the pressure can reach more than 0.6 MPa;
(2) confirmed spray steel shot abrasive particle size, shape, hardness, mixing ratio, degree of clean all meet the requirements;
(3) before spraying steel shot derusting of environmental temperature, relative humidity, dew point temperature, the temperature of steel plate for testing, to ensure that the environmental conditions meet the requirement of steel shot injection;
(4) after spraying steel shot derusting descaling grade, roughness derusting quality testing, ensure that quality derusting meet the technological requirements.
3 coating quality control
1) coating before use, should first check on the package name, batch number, colour, curing agent and diluent kinds is in line with the requirements, such as more than banning the use of storage period of the coating;
Before (2) the coating mixture, the main agent first and then according to the proportion of zinc powder was added and fully stirring, until the color uniform, so far no precipitation in the bottom according to different temperature and construction conditions, appropriate add thinner to adjust construction viscosity;(3) coating spraying on the environment temperature, relative humidity and dew point temperature, the temperature of steel plate for testing, to ensure that the environmental conditions meet the coating requirements, at the same time, should check the air pressure, spraying equipment, gun nozzle type, etc., to ensure that meet the requirements may start spraying;(4) as the zinc powder in the solvent inorganic zinc rich primer easy precipitation, therefore in the process of coating on coating should also continue stirring, prevent dust precipitation;(5) coating spraying process should strictly control the spraying Angle, spraying distance, spray speed and scope of lap, avoid sagging or dry spray phenomenon;
(6) coating, should use wet film thickness gauge measuring constantly wet film thickness, to control the dry film thickness is in conformity with the design requirements.
Coating quality inspection
1 to detect the thickness of the coating dry film
Coating dry film thickness testing should be done after the coating work, because the end of solvent inorganic zinc-rich paint film thickness is too thick (generally refers to the thickness of more than 100 microns) prone to cracking, so for the part of the film thickness of more than 100 microns should adopt steel grit paper burnish to under 100 microns;For the membrane thickness of more than 50 microns thick, can not meet the design of the parts available intermediate coat thickness, the reason is that should not be solvent inorganic zinc rich primer painting, and 50 microns solvent inorganic zinc rich primer can meet the requirements of anti-corrosion;For coating work after the damage or the part of the thickness is less than 50 microns, filling besmear epoxy zinc rich primer should be adopted to design the film thickness.
2 coating appearance test
Solvent inorganic zinc rich primer coating appearance requirements without sagging, crack, flake, granular and other defects.Due to the coating with high solid content, the features of quick drying, spray coating surface after often can form a layer of loose grain, before sealing paint coating steel grit grinding paper should be adopted to remove all loose particles, so as to ensure the adhesion between the coating and reduce the intermediate paint or paint surface porosity and the incidence of pinhole.
3 coating curing test
Solvent inorganic zinc rich primer curing more fully, intermediate paint or paint coating on the surface of the lower the risk of pinhole.Sealing paint coating, therefore, should be in solvent inorganic zinc rich primer cured completely, but as a result of solvent inorganic zinc rich primer curing conditions both temperature requirements, at the same time have asked to humidity, recoat time is difficult to determine, construction site usually use COINS stroke brush coating curing method or solvent cleaning method.