With the development of precision casting, investment sand treatment and investment mold coating have been widely concerned by casting customers. Sanzhuji combined with investment sand treatment equipment and coating supporting enterprises, summarized and concluded the coating configuration of investment mold casting, hoping to be helpful to the casting enterprises.
The physicochemical parameters of silica sol mainly include: SIO2 content, density, Na2o content, PH value, kinematic viscosity, colloid particle diameter, etc. These physicochemical parameters mainly affect the shell strength, coating stability and coating powder to liquid ratio.
Because it is difficult for investment casting enterprises to detect these physical and chemical parameters, on the one hand, to strengthen the selection, evaluation and confirmation of the supplier, on the other hand, the surface layer and the back layer should choose to use different specifications of silica sol, the surface layer to choose S-830 silica sol, the back layer to choose S-1430 silica sol. The composition of paint in investment casting will directly affect the quality of casting, so let''''s first understand the composition of paint.
Coating preparation generally add silica sol, then add wetting agent mix, add refractory powder in the stirring, finally add defoaming agent. In order to ensure the coating quality, the surface coating is all new material, mixing time should be more than 24h to use, such as part of the new ingredients, mixing time can be shortened to 12h. The mixing time of the transition layer and the back layer coating can be less than that of the surface layer coating. When all the coatings are newly mixed, the mixing time is more than 10h. When some are newly mixed, the mixing time can be reduced by half. If the coating is not used, it should be sealed to prevent water evaporation.
Sanzhuji suggests that it is best not to add paint in the shell making operation, but to set up special paint preparation equipment.
Qingdao Sanzhuji Equipment Manufacturing Co., Ltd. specializes in the production of Green Sand Molding Line,Self-hardening sand molding line,foundry machines,Sand molding machine,Sand casting equipment,sand mixer,GS high efficiency rotary mixer,Resin sand mixer,no-bake resin sand mixer,Jolt squeeze molding machine/Jolt-squeezing moulding machines,Multi- Piston Moulding Machine/Hydraulic multi-piston moulding machine,sand casting molding machine,sand reclamation equipment，foundry molding machine,flaskless moulding machine,shot blasting machine,dust collector,according to the amount of old sand recovered Carry out plan customization, and provide sand reclamation equipment installation, commissioning, and training. Welcome guests to visit the factory.
