137 results about "Evaporative-pattern casting" patented technology

Provided is an evaporative pattern casting process wherein a casting process plan capable of attaining the optimal discharge of generated gas can easily be decided. The present invention is an evaporative pattern casting process for casting a product, which comprises pouring a molten metal in a mold in which a pattern made of an expanded synthetic resin is embedded in molding sand, and evaporating the pattern with the molten metal, while gas generated by evaporation of the pattern is discharged outside the mold through a discharging passage comprising a discharged gas suppressing means, wherein the ventilation of the discharging passage is controlled on the basis of the material and the shape of the pattern and the kind of the molten metal and the temperature of the molten metal.

The present invention relates to a evaporative pattern casting special-purpose magnesium alloy and its smelting method. It is characterized by that in the formula of magnesium alloy the content of zinc is reduced, the contents of Al and Mn elements are properly regulated, and the mixed rare earth RE richly containing Ce and elements of Ti and C are added so as to fine the crystal grains of evaporative pattern casting magnesium alloy, reduce its dispersed shrinkage defect and improve its casting property and mechanical property.

The invention relates to an aluminium alloy or magnesium alloy lost mould casting pressuring solidification method and a device thereof, and the invention belongs to the field of special precision casting. The aluminium alloy or magnesium alloy lost mould casting pressuring solidification method comprises compacting, vacuuming, pouring, pressuring and depressurizing. A pressure resistant sand box of the device is a cylinder-shaped container, the bottom is provided with an exhaust valve, and the inner lower part or the side wall is provided with a ventilation interlayer; the upper surface of a cover of the pressure resistant sand box is respectively provided with a switch valve, a safety valve and a pressure gauge; and the side surface of the pressure resistant sand box or the cover of the pressure resistant sand box is provided with an intake pipe. The aluminium alloy or magnesium alloy lost mould casting pressuring solidification method can obviously reduce casting defects of shrinkage cavity, shrinkage porosity, and the like in aluminium alloy lost mould casting, can effectively reduce pinhole in the aluminium alloy, enhances density of the casting, thins alloy crystal grains, and improves the surface quality and mechanical property of the aluminium alloy or magnesium alloy lost mould casting. The device simplifies lost mould casting pressuring solidification technique, and low production cost, convenient operation, good sealing effect, short sealing time of the sand box and fast pressuring speed.

The invention discloses a high-efficiency and energy-saving aluminum alloy evaporative pattern casting production line. The high-efficiency and energy-saving aluminum alloy evaporative pattern casting production line comprises a sand box automatic circular line, wherein a plurality of box bearing carts which move along a conveying line and are used for bearing sand boxes are arranged on the sand box automatic circular line; the sand boxes are borne on the box bearing carts; the box bearing carts sequentially pass through a bottom sand adding station, a model cluster storing station, a sand filling and modeling station, a pouring station, a casting discharging station and a sand falling station on the conveying line through a servo box pushing system; the pouring station comprises a pouring machine and a tundish changing system; a casting taking robot for taking out castings in the sand boxes is arranged at the casting discharging station; and a bottom-dump type sand falling device for dumping molding sand in the sand boxes from the bottoms of the sand boxes is arranged at the sand falling station, or a box turning machine is adopted for automatically turning over the boxes to finish the sand falling. The production line has the characteristics of high degree of automation, high production efficiency, stability, reliability, energy conservation, environment friendliness and the like.

The invention relates to molding sand for die casting. The molding sand is composed of quartz sand, limestone sand, chromium ores, zircon sand and emery. The molding sand is suitable for evaporative pattern casting, not prone to adhesion to sand, settlement shrinkage or earthworm cracking and low in cost, the reusability and collapsibility are good, and hidden dangers to health of workers are reduced.

The invention provides a method for preparing an overall shell mold by utilizing vaporizing combustion of mold shell roasting pattern. The method comprises the following steps: preparing a plastic mold by adopting an injection molding method, splicing and assembling the plastic mold to form an overall pattern, and coating, sanding, drying and hardening the overall pattern, thus obtaining a solid mold shell; roasting the obtained mold shell, wherein the pattern disappears due to vaporizing combustion, thus obtaining an overall shell mold; and finally, cleaning and pouring the obtained shell mold, thus obtaining the casting. The method is high in applicability, the complexity of the cast alloy types and casting structures is not limited, the processes of investment casting and dewaxing are reduced, the production cycle is shortened, and the production efficiency is improved. In the process of manufacturing the shell mold, a phenolic resin is not used as an adhesive, and the problems of pungent smell and subskin blowholes of castings in the process of casting and pouring the shell mold are solved. The pattern disappears before pouring due to roasting and vaporizing combustion of the mold shell, the defects of evaporative pattern casting steel casting recarburization and iron casting wrinkled skin are overcome, and the casting quality is improved.

The invention relates to a method for preparing a TiC+Al2O3 particle-reinforced steel-based surface-recombined excavator form-relieved tooth. The method disclosed by the invention comprises the following steps: preparing an alloy powder coating by using titanium dioxide, iron scale powder, aluminium powder, ferrotitanium powder, carbon powder and an organic binder; pressing the alloy powder coating into pieces, and adhering the pieces to two working tooth surfaces of a foamed plastic EPS (expanded polystyrene) model of the excavator form-relieved tooth; then, preparing an EPS appearance of the form-relieved tooth through externally coating an anti-sticking sand coating and drying; and smelting molten steel in a medium-frequency induction furnace or an electric-arc furnace, and carrying out casting moulding by using a V-EPC vacuum evaporative pattern casting method. Through testing, in the prepared particle-reinforced steel-based surface-recombined excavator form-relieved tooth, a composite layer and a steel substrate form a metallurgical combination state; the composite layer is dense in organization, and the thickness of the composite layer can reach more than 3 mm; the surface hardness HRC of the composite layer can be greater than or equal to 53; and compared with similar excavator form-relieved teeth which are not subjected to surface composition, the service life of the excavator form-relieved tooth can be prolonged by 2-3 times.

Provided is an evaporative pattern casting process wherein a casting process plan capable of attaining the optimal discharge of generated gas can easily be decided. The present invention is an evaporative pattern casting process for casting a product, which comprises pouring a molten metal in a mold in which a pattern made of an expanded synthetic resin is embedded in molding sand, and evaporating the pattern with the molten metal, while gas generated by evaporation of the pattern is discharged outside the mold through a discharging passage comprising a discharged gas suppressing means, wherein the ventilation of the discharging passage is controlled on the basis of the material and the shape of the pattern and the kind of the molten metal and the temperature of the molten metal.

The invention relates to a die casting method. The die casting method includes the following steps that (1) a foam board is machined into a foam model; (2) the surface of the foam model is coated with a refractory material; (3) the foam model coated with the refractory material is dried; (4) the foam model treated in the step (3) is buried in molding sand for vibration molding; (5) liquid metal is poured under negative pressure so as to gasify the foam model; and (6) after the poured model in the step (5) is cooled, a cast part in a sand box is separated from dry sand, and the die cast part is obtained. The molding sand in the step (4) is composed of the following raw materials of quartz sand, limestone sand, chromium ores, zircon sand and emery. The die casting method is suitable for evaporative pattern casting, not prone to adhesion to sand, settlement shrinkage or earthworm cracking, low in cost and capable of reducing hidden dangers to health of workers, and the reusability and collapsibility are good.

The invention discloses a high manganese steel sieve plate for a crusher and a preparation method of the sieve plate. The sieve plate comprises a base plate, wherein a plurality of sieve holes are formed in the base plate; the base plate is made from high manganese steel; the high manganese steel comprises chemical element components in percentage by mass as follows: 1.25-1.45 % of C, 13.5-15.0 % of Mn, 2.5-3.5 % of Cr, 1.2-2.5 % of Si, 0.15-0.35 % of Mo, 0.35-0.55 % of B, 0.15-0.25 % of Ti, no more than 0.05 % of S, no more than 0.05 % of P and the balance of Fe. The preparation method comprises the steps of evaporative pattern preparation, modeling, smelting, slag removing, modification treatment, pouring, sand removing, water-toughening and the like. Compared with the prior art, the high manganese steel sieve plate for the crusher is manufactured by adopting high manganese steel with an evaporative pattern casting method; and the manufactured sieve plate has the advantages of excellent wear resistance, high strength, long service life, low cost and the like.