1072 results about "Lost-foam casting" patented technology

The invention discloses a special coating for pulverous expendable pattern casting and casting iron, and the special coating comprises 60-70 percent of 180-200 mesh refractory materials, 2.0-3.0 percent of suspending agent, 1.5-2.5 percent of adhesive, 0.3-0.6 percent of organosilicon defoamer, 0.01-0.03 percent of preservative agent and 180-200 mesh residual mica powder in balancing amount. When the special coating is prepared, various pulverous materials are weighed according to the required proportion, interposed into the powder stirrer in sequence to stir for 20 to 40 minutes at a low speed and then discharged and packed. When the coating is used, appropriate water is interposed into the stirred vessel by the powder-to-water ratio of 1 to (1.1-1.4). After the stirred vessel is turned on, the powder coating weighed is interposed in batches. The coating is utilized after preparing into slurry; therefore, the special coating has the advantages of good suspension property, high intensity, uniform coating, good thixotropy, good leveling property, glabrous surface, no bubbles, no cracks and the like. Moreover, the user can adopts the dip-coating method, the hang-coating method and the brush-coating method, the viscosity change of coating materials can be decided upon the demands of the user, and different viscosities can realize different coating thicknesses.

The invention relates to an expendable pattern casting (EPC) molding shell paint for casting steel, and the EPC molding shell paint comprises surface a layer fireproof paint and a back layer reinforcing paint, wherein the surface layer fireproof paint comprises the following components in parts by weight: 80-90 parts of high-chromium alundum powder, 10-20 parts of calcined kaolinite, 6-8 parts ofcalcium rectorite powder, 1-3 parts of sodium tripolyphosphate, 3-5 parts of polyvinyl formal solution, 0.3-0.5 part of ethoxylated alkyl sodium sulfate, 0.6-1.0 part of polyether type modified polydimethylsiloxane and 60-75 parts of water; and the back layer reinforcing paint comprises the following components in parts by weight: 75-85 parts of coal gangue sand, 15-25 parts of kaolinite, 3-6 parts of feldspar powder, 8-13 parts of calcium rectorite powder, 8-10 parts of sodium tripolyphosphate, 1.5-2.0 parts of wood fiber and 30-45 parts of water. A molding shell manufactured by the surface layer fireproof paint and the back layer reinforcing paint has the characteristics of high strength and refractoriness, good air permeability and the like.

A method of an in situ synthetic steel bond hard alloy casting composite hammerhead adopts a vacuum lost foam casting technology, wherein Ti powder, graphite powder, W powder and metal powder are mixed, and are added with an adhesion agent to produce a powder coating paste, the powder coating paste is filled in a reinforcement groove or a hole of a working part of an expanded poly styrol (EPS) foaming plastic modal of a hammerhead casting, during the pouring process, the high temperature of liquid steel is utilized to initiate the self propagating synthesis reaction, the reactions of Ti plus C->TiC and W plus C->WC are carried out, so the TiC and WC-based hard alloy phases are formed, the liquid steel is filled into the clearance of a hard phase, so an in situ synthetic titanium carbide and tungsten carbide steel bond hard alloy is obtained, and the hard alloy is embedded in the steel base body of the working part of the hammerhead. When the hammerhead which is produced through the method of the in situ synthetic steel bond hard alloy casting composite hammerhead is used, because the hard alloy and the casting are completely, metallurgically and firmly combined together, the hammerhead has high wear resistance and impact resistance during the use, has a simple technological process, low production cost, and is applicable to large-scale industrial production.

The invention discloses a crusher hammerhead cast of a steel bond hard alloy bar and a casting method of a vanishing mould thereof. The hammerhead is cast by low-alloy steel and is cast with the steel bond hard alloy bar in the casting process; the low-alloy steel contains the following chemical components by weight percent: 0.24 wt% to 0.295 wt% of C, 1.32 wt% to 1.56 wt% of Si, 0.028 wt% to 0.035 wt% of S, 0.032 wt% to 0.038 wt% of P, 0.82 wt% to 1.22 wt% of Mn, 1.67 wt% to 2.10 wt% of Cr, 0.42 wt% to 0.51 wt% of Mo, 0.05 wt% to 0.08 wt% of V, 0.05 wt% to 0.07 wt% of Ti, 0.08 wt% to 0.15 wt% of RE and 93.942 wt% to 95.29 wt% of Fe. The casting method of the hammerhead comprises the production process of the low-alloy steel, and the casting process and the thermal treatment process of the vanishing mould. The hammerhead product cast with the steel bond hard alloy bar has the advantages of good strength and toughness and high rigidity and abrasive resistance, is suitable for various working conditions, and can crush objects with different hardness.

The invention discloses a method for lost foam casting of a composite two-liquor bimetallic hammerhead of a crusher. The method includes: embedding a crusher hammerhead molded body made of foam plastics into dry sand of a sand box, and vacuumizing; then respectively preparing high-chromium iron casting liquor and carbon steel casting liquor; after melting down and deoxidizing the two kinds of metallic casting liquor, performing carbon steel pouring (1300-1400 DEG C) prior to high-chromium iron pouring (1550-1650 DEG C), and rapidly covering high-chromium iron liquor by thermal insulation agents after pouring is completed; subjecting a molded crusher hammerhead casting to thermal treatment at the temperature of 900-1000 DEG C, then rapidly discharging the casting and cooling the casting in air; and tempering at the temperature of 250-300 DEG C finally.

The invention relates to a vibration solidification method of lost mold casting, pertaining to the precision casting field, which aims at fining the organization of castings of the lost mold casting, reducing the cost and enhancing the performance of castings. The invention comprises three steps of: production of foamy mold, imbedding the foamy mold into a casting box for filling and compacting sand as well as casting of molten metal; the invention is characterized in that: before and during the period of casting molten metal, during the solidification period, or the solidification period after the period of casting molten metal, casting box filled with foamy mold and scattered sand is vibrated at the frequency ranging from 10 to 100Hz and the amplitude ranging from 0.1 to 3.0mm, and rotation speed of a vibration motor that drives the vibration is 750 to 3000 rpm, and the vibration is stopped after the solidification of casting is completed. The invention has the advantages of low cost, easy operation and control, obvious fining effect of casting organizations, greatly improving performance and no environmental pollution, which is both suitable for the casting of the lost molds of nonferrous metals components, such as aluminum alloy, magnesium alloy, copper alloy, etc., and is also suitable for the casting of the lost mold of ferrous metal components, such as cast iron, cast steel and so on.

The invention relates to a technique for producing a dual-liquid dual-metal composite wear-resistant lining plate by lost foam casting, comprising the following steps: 1) manufacturing a foam lining plate model; 2) installing two casting systems; 3) coating lost foam paint on the foam lining plate models, and baking; 4) adding dried quartz sand and compacting; 5) continuously adding the dried quartz sand to be full, then using a plastic film to cover and seal a sand box, installing a sprue cup to respectively connect a wear-resistant straight pouring gate of a lower spure and a casting steel straight sprue of an upper sprue, and vacuumizing a gas path on the lost foam sand box so as to fasten a casting mold; 6) firstly pouring wear-resistant molten iron, and then pouring molten steel; and 7) after the pouring is finished, closing a vacuum system of the lost foam till the dual-liquid dual-metal composite wear-resistant lining plate is taken out of the box after solidification and cooling. The technique has the beneficial effects that the service life is prolonged, the large amount of metal materials are saved, the difficult problem of hard matching of the wear resistance and the toughness of a whole piece is solved, and the difficult problems of no mixing and no box collapse when the lost foam is used for pouring two types of molten iron are overcome.

The invention relates to a vacuum negative pressure lost foam casting process, which belongs to the technical field of casting. The process comprises the following steps: an integral mold of a screw is obtained by using resin bonded sand with a nut which has the same inner surface geometric parameters as that of or a little bigger internal diameter than that of a screw hole to be processed; the mold of the screw is taken out, coated with a coating and baked dry; then a hole is cut at the position of the screw hole to be processed on the integrally cast overall mold; finally the screw mold is inserted into the cutting hole and assembled to form the final mold; that is, the vacuum negative pressure lost foam casting process can be directly used for casting a casting with the screw hole, which creates a precedent of directly casting small-aperture screw holes without reprocessing in the casting field. The screw hole processed by the process can ensure precision and needs no reprocessing. The vacuum negative pressure lost foam casting process is especially applicable to the vacuum negative pressure lost foam casting of the casting with a plurality of screw holes, small size and high precision.

The invention discloses a lost wax shell-based negative pressure dry sand and iron shot chilling vibrational composite casting process method. The method is characterized by comprising the following steps of: feeding a shell manufactured by a lost wax process into a chilling sand box; loading steel shots in the gap between the shell and the chilling sand box; feeding the chilling sand box into a sand box with a vacuumized negative pressure model; fully filling dry sand between the chilling sand box and the sand box with the vacuumized negative pressure model; paving a plastic film; placing a pouring cup; and pouring under the simultaneous vacuumizing and vibrating condition. By the method, the strength of molding sand is high, a chilling effect is good, the process characteristics of lost foam casting and hot investment casting are combined, the defect of foam-gasified carbon special for the lost foam casting is overcome, the chilling effect of the iron shots is fully exerted, the pouring is performed under the vibration condition, and alloy grains are refined, so that wear-resisting castings have higher density, hardness and wear resistance.

The invention provides a method for preparing a ceramic particle reinforced steel-based mesh material, which comprises: forming a mixture of hard ceramic particles and alloy powder into strip blocks by powder sintering or by using and adhesive; joining the strip blocks into a corresponding mesh structure or joining and overlapping the strip blocks into mesh three-dimensional framework structure; and performing normal sand casting or lost foam casting, namely melting a substrate metal material, pouring the molten substrate metal material in a molding cavity, allowing the molten substrate metal material to cool and condense at room temperature, removing sand and obtaining the ceramic particle reinforced steel-based mesh material. The obtained ceramic particle reinforced steel-based mesh material gives full play to the high wear resistance of the ceramic particle hard phase and the toughness of the steel base; and the method with convenience for regulation and reliable process solves the problem of incomplete reaction of the composite material, nonuniform reinforcing phase particle distribution, pollution weakening on a reinforcing phase interface and the like and is used in wear resistance fields of mines, power, metallurgy, coal, building materials and the like.

The invention discloses a method for eliminating carbon defects by adopting a high-performance coating, negative-pressure firing, vacant shell pouring and quick airflow cooling in lost foam casting. The process comprises the following steps: placing a mould into a sand box; filling dry sand into the sand box; sealing the upper surface of a sand layer with a plastic thin film; starting a vacuum pump, igniting and gasifying the foam mould from a pouring gate under a negative pressure condition so as to form an intact vacant shell cavity, wherein over 95 percent of carbon is discharged out of the molding sand box; pouring molten iron and steel; lifting or cutting the sealing thin film on the top surface of the sand box when the molten iron and steel is in a temperature area where a liquid phase and a solid phase coexist, and then sucking cold airflow into the sand box so as to quickly cool a cast piece; and after stopping the pouring, continuing extracting air for 3 to 6 minutes, and then stopping the vacuum pump. The method can realize the elimination of the carbon defects of the cast piece, grain refinement, and easy falling-off of the coating by discharging and reducing carbon and pouring the vacant shell in the lost foam casting, makes the cast piece have bright and clean surface to comprehensively improve the quality of the cast piece, saves energy and reduce consumption, is high in efficiency and benefit and is applied to industrialized mass production.

The invention provides a production method for water-based coating which is specially used for lost die. The composition of the water-based coating comprises: amorphous graphite powder, flaky graphite powder, bentonite, hydroxymethyl fiber, milk-white glue, corn starch, dextrin and BY adhesive. The composition proportion is 50% of the amorphous graphite powders, 50% of flaky graphite powders, 5-10% of bentonite, 3-5% of hydroxymethyl fiber, 1.5-3% of milk-white glue, 3-5% corn starch, 3-5% of dextrin and 2-3% of the BY adhesive. The method of the invention solves the problems that the currently usually used lost die is easy to cause that the casting is easy to be deformed, cracked, delaminated, stuck with sand on the surface, non-smooth and difficult to remove the stuck sand, thereby affecting the quality of the casting and being suitable for application in the casting production of the lost die.

The invention discloses a preparation method of a water-based coating for lost foam casting. A coating prepared by the preparation method has excellent performances, good suspensibility, thixotropy and permeability, and high surface strength. The preparation method overcomes the defects that refractory powder adopted by the conventional casting coating preparation technology is very expensive and a coating production cost of the conventional casting coating preparation technology is high. A casting coating obtained by the preparation method is smooth and has appropriate viscosity. Through the preparation method, a high-quality casting coating can be prepared from cheap raw materials through simple production processes. Therefore, the preparation method reduces a coating production cost and realizes good finished product quality.

The invention discloses a method for casting disappear mould of the cover of diesel engine and petrol engine that based on disappear mould technique, which can solve the problems of present sand casting technique with high material consumption, heavy cast, and environment pollution, etc. The invention slices matter into several mould plates to prepare the mould; than filling the material of disappear mould into mould to attain the mould plate of disappear mould which is the same with said matter; dipping disappear mould dope on the mould plate and arranging it into sand tank to be vibrated and poured to melt mould plate into carbon monoxide and carbon dioxide to be discharged to attain the cast of said matter. The invention has the advantages that save raw material, reduce labor intensity and improve property.

The invention discloses a method for manufacturing a casting blank of a refrigerator inner container die by using a lost foam casting process, and relates to the technical field of die manufacture. The method comprises the following steps of: three-dimensional modeling, module segmentation, foam processing, module adhesion, coating immersion, model drying, embedded compaction, molten aluminum pouring, vacuum negative pressure, normal-temperature cooling, un-boxing and clearing to obtain the casting blank of the refrigerator inner container die. The casting die has short blank casting period, the natural shape wall thickness of the die is accurate, the casting is light in weight, the labor intensity of a worker is low, the production efficiency is high, and the labor cost and the manufacturing cost are reduced; and the method is an energy-saving and environment-friendly 'green' project.

The invention discloses a wear-resistant hammer head of a hammer crusher with movable installation position and a manufacturing method thereof. The hammer head is manufactured by super-high manganese as raw material by lost foam casting. The hammer head comprises an end part (3) and a handle part (6); hard alloy bars (2) are cast in the two working surfaces of the end part (3) of the hammer head; and an first installation hole (4) and an second installation hole two (5) are formed on the handle part (6) of the hammer head at a distance. The hammer head has good strength and toughness and high hardness and wear resistance and is applicable to the crusher hammer head with single magnitude between 500 and 700 N. When a certain length of the end part of the hammer head is worn, the installation position is moved and the hammer head can be continuously used, being equivalent to replace a new hammer head, so that the purpose of prolonging the service life of the hammer head is fulfilled.

The present invention discloses vanish mold casting process of middle channel casting. The vanish mold casting process includes the following steps: 1. forming casting mold through filling cured foamed polystyrene into mold and stoving casting mold; 2. spraying paint onto the casting mold and drying at 55 deg.c for 12-15 hr to form coating of 1.2-1.5 mm thickness; 3. setting the casting mold into sand box, filling mold sand, vibrating in vibrator to densify and covering the upper port of the sand box with plastic film; and 4. casting through turning on the vacuum pump, pouring molten steel, shaking out sand after cooling for 1 hr, cleaning and spraying paint. The present invention has the following features: main material comprising waste steel and small amount of alloy elements resulting in low cost, precise size, smooth surface and high carbon layer formed in the surface of casting resulting in raised wear resistance and long service life.

The invention discloses a shell casting method through contraction and then gasification of high-performance coating foam and a mold sample of an evanescent mode. The method comprises the following steps of: manufacturing the mold sample; preparing an inner-layer coating and an outer-layer coating; spreading the coatings; drying the coatings; performing reduction and contraction; performing gasification and evanescence; and packing and casting, wherein the inner-layer coating is prepared by mixing and stirring an additive special for a Guilin No. 5 evanescent mode coating, refractory aggregate powder with 180-220 meshes and water; and the outer-layer coating is prepared by mixing and stirring an additive special for a Guilin No. 5 evanescent mode coating, refractory aggregate powder with thickness being 70-100 meshes and180-220 meshes in half and water; According to the method, the mold sample has sufficient strength, dimensional accuracy and surface smoothness; carbon defects such as recarburization, slag inclusion, air holes, cockles and carbon black caused by the foam mold sample can be eliminated; the method is applicable in casting the evanescent mode with any steel; the situation that 5-10 layers of coatings are coated, and 5-10 layers of dry sand are spread when in investment casting does not needed; roasting at the temperature of 1000 DEG C in a kiln is unnecessary; and the process is simple, has low cost, and has energy conservation and emission reduction.

The invention provides a preparation method of a hard alloy/high-chromium alloy-based wear-resistant composite material, which comprises the following steps: firstly manufacturing a hard alloy/enhancement body, welding an iron nail at one end of the hard alloy enhancement body, then plating a metal buffer layer on the surface of the hard alloy enhancement body welded with the iron nail, further manufacturing a wearable element model, further inserting the well prepared hard alloy into the wearable element model on the premise of enabling the iron nail to face towards outside, adopting the expendable pattern casting process to cast high-chromium alloy, taking out a cast after casting molding, cutting off the iron nail, using a diamond grinding wheel to polish the working surface to be smooth, and then performing heat treatment on a workpiece. The composite material is uniform in distribution of enhancement phase, large in controllable range of volume fraction, small in residual stress of an interface, small in heat-affected zone and good in combination, hard alloy of the composite material is positioned in the surface layer of the working surface of a wearable element, the thickness is 10-15mm, and the composite material can be used for manufacturing normal-temperature or high-temperature wear-resistant wearable elements in the fields of mines, building, metallurgy, electric power and the like.