Fouling and cleaning of making resin sand core box is a problem for many enterprises in China has not been able to solve. Scaling core box not only caused by the casting die surface roughness. Serious impact on the appearance quality of sand core, resulting in the casting dimension precision sticky sand, reduce, serious when can cause the casting and die casting scrap bulk waste. The formation mechanism of fouling making resin sand core box, mainly due to resin core sand surface by sand jet flow impact on the sand shooting process, part of the resin fracture, small amount of resin is extruded adhered to the surface of core box, tip of the day gradually hardening resin scale a layer of hard, dense in the core box surface. Therefore, the sand shooting pressure is too large, poor quality of core sand resin, resin content is too high, the release agent and the resin does not match; the core box surface roughness will prompt box scale. making domestic and foreign enterprises in the core box cleaning using a variety of methods for cleaning. making 1) using chemical cleaning agent.
Making 2) using liquid or solid sand blast cleaning. making 3) by dry ball spray cleaning cartridge.
Making clear the following method are introduced: making below 1, liquid sandblasting machine cleaning box Making 1) principle to the grinding liquid pump and compressed air as a driving force, grinding high speed jet to the mold surface by spray gun, reach the finishing die casting purpose. Grinding fluid is a protective effect of carrier liquid with a certain size of die abrasive (white corundum sand, glass beads and other artificial abrasive) proportional mixing, storage box placed in the lower part of the body. When the grinding liquid pump will be grinding liquid tank in the certain pressure and flow through the grinding liquid pipeline input gun. At this time, and a grinding fluid bypass the device in high speed stirring nozzle which, thereby allowing the tank in abrasive and carrier liquid stirring evenly; the compressed air from the external air source through (premium) solenoid valve relief valve, into the spray gun. The gun is the main component of the direct execution of liquid spray job. It and the grinding liquid and compressed air pipeline system is arranged in the upper part of the machine body is connected, sealed working chamber. Jet of grinding fluid on casting die surface impact grinding, from disk worktable flow, the mesh board return tank, so the cycle is complete on the jet cleaning of casting die.
Making 2) cleaning process according to technological requirements of core box is different, there are two kinds of working modes available: ① without compressed air, depending only on the grinding liquid pump supply grinding fluid, accelerated through a nozzle onto the cleaned Centrifugal Casting mold. Applicable to the regular general cleaning and maintenance of the core box. The grinding system and compressed air system started at the same time, to the gun while providing a grinding liquid and compressed air, make its in the spray gun after mixing, the nozzle to the Centrifugal Casting mold surface high speed gas jet, abrasive flow. Due to a gas pump, and way of working, the ejective gas, grinding fluid flow with greater pressure, be borne grinding fluid kinetic energy of particle fluid parcel increase, improve the core box cleaning ability (mainly suited for cleaning surface of core box resin fouling). making 3) process and parameters using liquid sandblasting machine, compressed air pressure is 0.5 ~ 0.7MPa, spray distance is about 10 ~ 120mm.
Making the cleaning medium with particle size of 90um glass beads or 0.125mm (120 mesh) white corundum sand cleaning and maintenance of the core box (or clear scaling), general core box regular cleaning and maintenance time ≤ 1 2min, while for the surface of a core box resin fouling cleaning time, as the core box the size, scale thickness, shape complexity and decide, usually in the range of 5 to 20min can be cleared box of dirt, and injection time on the core box the size precision and the surface roughness does not affect the basic.
Making 4) process is production efficiency and economic benefit using liquid sandblasting machine and glass bead cleaning box basically can be the core box surface thick resin fouling clean, but for a long time without cleaning groove fouling very thick, but difficult to clean.