Research On Digital Molding Process Of Integral Multi-way Valve

In the field of hydraulic transmission of engineering machinery,hydraulic manifold valves have become the core control components of hydraulic engineering machinery due to their compact structure,simple piping connection and low pressure loss.Their performance has also become a measure of a country's hydraulic pressure.In this paper,the complicated integral hydraulic multi-way valve is designed for casting process,and the front casting process is optimized through numerical simulation.The optimized casting system and mold structure are obtained;the multi-way valve core is realized through digital additive manufacturing technology.One-piece molding,combined with CNC machining technology to establish the mold processing technology and simulation,to complete the production of the entire sand mold;multi-way valve casting mold and cast to obtain a multi-way valve casting;through the three-dimensional scanning of the workpiece,The whole process carries on the quality examination,simultaneously obtains the point cloud data.This experiment is based on the technique of composite contour laser rapid prototyping.This method introduces a fuzzy sintering model to achieve high-speed scanning of laser parts,and then increases the precision profile of the laser energy density scan model to destroy the sintering of the area outside the contour.The relationship between the laser sintering intensity and the laser failure intensity was studied for the above method,and the laser sintering process was determined,and the digital integral molding of the complex integrated sand core was realized.The parts produced by the composite profile laser molding consist of three parts: the target part,the failure layer and the shell layer.The removal of the shell layer and the failure layer is an important part of the research.In the experiment,the laser failure process was used to develop a supporting strip.Molding system effectively achieves sand mold release.In the experiment,a complex thin-walled multi-valve valve core was used as the research object,and a vacuum-impregnation process was used to infiltrate different concentrations of sodium silicate/silica mixed liquor on the cured film-coated sand,and tested the mixed solution concentration on the film.The influence curve of the normal temperature tensile strength and high temperature residual strength of the sand type was observed,and the morphology distribution of the mixed solution with different concentrations in the coated sand type was observed and compared by using SEM.The results show that the vacuum infiltration process can completely infiltrate the sodium silicate/silica mixture into the sand.After the mixture is hardened,the maximum tensile strength of the sample at room temperature reaches 8.38 MPa,and the strength increases by more than 5 MPa;at a high temperature of 1000° C.Under the condition of heating for 5 minutes,the sample containing sodium silicate still has high strength,the surface of the sample is complete,and no sand grains fall off,while maintaining a certain degree of collapsibility of the sample.Through this process research,it is effective to prevent major casting accidents such as floating cores and broken cores during the high-temperature casting process and improve the casting yield.In the experiment,three-dimensional scanning technology was used to collect and track product quality data for castings and castings that were digitally manufactured.Coloring imaging techniques were used to inspect flaws on the surface of the castings to detect macroscopic defects in the section castings.Industrial CT was used for multiplexing.Non-destructive testing inside the valve castings;Through the above-mentioned technical methods,to achieve a comprehensive evaluation of the product,multi-way valve castings overall size tolerances meet the national standard GB/T 6414-CT6 level,higher than the general manual sand casting CT11 ~ 14 level,machine Casting CT8~12 level,metal casting CT8~10 level and sodium silicate investment casting CT7~9 level,lower than the silica sol investment casting CT4~6 grade.