43results about How to "Achieve sequential solidification" patented technology

A technology for integrally casing large bearing steel roller features that the computer simulation technique is used to design metal mould, the sand covered iron mould and insulating raiser head are used for sequentially solidifying, and the new pouring system and the rotary filling of tangent internal sprue are used for preventing air bubble and impurities, resulting in high quality of product.

A casting method for a large thin-wall valve body steel casting comprises the following steps: 1, manufacturing a composite physical model: manufacturing an upper half valve body external mold, a lower half valve body external mold, the overall frame of a second core box, and an irregular-shaped section template; filling a mixed filler between the frame and the section template; tamping, smoothly trimming the filler; performing natural curing after the dimensional requirement is met; 2, sand mulling; 3, modeling and core manufacturing; 4, painting, mounting the core, and combining boxes; 5, smelting and casting; 6, performing post-treatment. The large thin-wall valve body steel casting is prepared through the steps. The casting method adopting the composite model can improve the model manufacturing efficiency, saves wood, and reduces the model manufacturing cost; through the adoption of stepped flat ingate system, as well as the manner that a chiller, a riser and compensation are combined, the thin-wall valve body steel casting is protected from fracture, insufficient casting, cold shut, wrinkling, and other casting defects, so as to realize the sequential solidification of the valve body steel casting, and meet the technical requirement of the valve body steel casting.

The invention discloses a casting method of a hollow crankshaft of a slurry pump. A casting model is utilized. The casting method comprises the following steps: manufacturing an actual sample and a core box of the hollow crankshaft; installing a sand discharge box, a large open riser, a slag collector and a pouring channel, opening open and hidden air holes in a sand mold, and arranging anti-cracking ribs in a turning part I and a turning part III; manufacturing a sand core and a core head mold body, manufacturing a core bar main rod, forming two groups of via holes in the core bar main rod, and welding a steel round positioning ring in each via hole; welding multiple reinforcing supports on the core bar main rod by reinforcing steel bars, winding a straw rope and a gas exhaust rope on the core bar main rod, putting a core bar into the core box, and filling sand for hardening; spraying paint; assembling the box; pouring; opening the box and spraying sand; polishing and repairing; normalizing; carrying out secondary sand spraying; and processing shaft holes in two end heads of the hollow crankshaft, thereby casting the hollow crankshaft of the slurry pump. The method provided by the invention can effectively prevent the structure defect of shrinkage cavity or shrinkage porosity partially.

The invention relates to the technical field of valve body casting and discloses a high-temperature high-pressure ultralow sulfur-and-phosphorus valve body casting forming process. A plane in which the centers of three pipe openings of a high-temperature high-pressure ultralow sulfur-and-phosphorus valve body casting part are located is used as a parting surface, first dead heads are arranged right above the three pipe opening respectively, second dead heads are arranged above the intersected positions of all pipes of the valve body casting part respectively, a plurality of chilling blocks are arranged under the intersected positions of all the pipes of the valve body casting part respectively, the chilling blocks are separated from the casting part by chromium ores, a bottom-returning type pouring system is adopted for pouring, a cross gate is positioned under the valve body casting part and is connected with a plurality of inner gates on the same horizontal plane, and an outlet in the top end of each inner gate is formed in the wall, close to the end surface, of the corresponding pipe opening. The valve body produced by adopting the casting forming process has the good casting forming quality, the formed matrix structure is compact, the CAE (Computer Aided Engineering) simulation technique is adopted, the production period of the casting part is shortened, the casting part manufacturing process is reasonably optimized, models and molding materials can be saved, the casting part production cost is reduced and the high economic benefit is achieved.

The invention discloses a stepped type pouring device. The stepped type pouring device comprises an upper-layer casting molding cavity, a lower-layer casting molding cavity, upper sprues and lower sprues. The upper-layer casting molding cavity communicates with the lower-layer casting molding cavity. Risers are formed in the upper end of the upper-layer casting molding cavity. The risers communicate with upper-layer pouring gates. The upper-layer pouring gates communicate with the upper sprues. The lower-layer casting molding cavity communicates with bottom-layer pouring gates. The lower endsof the lower sprues communicate with the bottom-layer pouring gates. The upper sprues are connected with the lower sprues through cut-off devices. Each cut-off device comprises a T-shaped cast pipe. Each T-shaped cast pipe is composed of a transverse pipe and a vertical pipe. Each transverse pipe communicates with a corresponding vertical pipe. The two ends of each vertical pipe are connected witha corresponding upper sprue and a corresponding lower sprue respectively. A spring is arranged in each transverse pipe. Each spring is fixedly connected with a blocking block. A soluble blocking needle is arranged at the end, away from a corresponding spring, of each blocking block. A groove is formed in the inner wall of each vertical pipe, and each groove is matched with a corresponding blocking block. By means of the stepped type pouring device, the temperature of positions of the risers are the highest; sequential solidification of castings is achieved; and feeding distance of the risersis improved greatly.

The invention provides a composite sand core for aluminum alloy casting. The composite sand core is prepared from the following raw materials by mass percent: 10-50% of iron powder with particle sizeof 40-140 meshes, 10-20% of limestone sand with particle size of 40-140 meshes, 5-10% of zircon sand with particle size of 40-140 meshes, and the balance of scrubbing sand with particle size of 40-70meshes. The cooling speed of a casting mold is regulated and controlled by improving the formula of the sand core, and multiple casting mold materials such as iron, limestone sand and zirconium sand are accurately compounded with molding original sand (scrubbing sand), so that the sand core is prepared; during molding, the sand core is embedded in the casting mold, so that the local thermal conductivity of the casting mold is changed, the temperature field of the casting mold is reconstructed, the sequential solidification of dispersed thermal section areas of a complex casting is realized, the ability of feeding a casting is improved, the grains are refined, and the loosening defect is inhibited.

The invention provides a forced cooling chassis and a method thereof. The forced cooling chassis comprises a base plate and a combination plate overlaid on the upper surface of the base plate; the combination plate is provided with a pouring hole and at least two drainage holes formed around the pouring hole, and the pouring hole and the drainage holes are arranged in a separated manner and penetrate the combination plate in the vertical direction; at least two molten steel grooves extending from the pouring hole to all drainage holes are formed in the upper surface of the base plate, and the pouring hole and the drainage holes are communicated through the molten steel grooves corresponding to the drainage holes and form a molten steel injection channel; and the combination plate comprises a back plate and a working plate overlaid and fixed to the upper surface of the back plate, the lower surface of the working plate and the upper surface of the back plate are attached in a sealing manner, a plurality of transversely-extending cooling through grooves for circulating cooling water are formed in the lower surface of the working plate or the upper surface of the back plate, and the cooling through grooves and the injection channels are not communicated. By means of the forced cooling chassis and the method, the cooling intensity of a steel ingot can be improved.

The invention relates to a preparation method of Mg-Zn-Ca series biomedical magnesium alloy, and belongs to the technical field of batch preparation of biomedical degradable magnesium alloy. The method comprises the steps of burdening, smelting and solidification system preparation, alloy smelting and purification, undercurrent transfer injection and forced filtration, precise solidification control and waste heat homogenization, near solidus homogenization treatment and plastic deformation treatment. The low-cost preparation technology has the greatest advantages that the preparation of a Mg-Zn-Ca series biomedical magnesium alloy ingot blank with the high thermal cracking tendency and the cross section area larger than 70000 mm <2> is met, homogeneous clean casting of industrial scale isachieved, and therefore the production efficiency can be greatly improved, the deformation degree is increased, and the performance is improved; and meanwhile, the cracking risk of a large cast ingotis greatly reduced, homogenization of a pasty area and a liquid phase area is achieved, the nucleation rate is increased, dendritic crystals are refined, and meanwhile specific gravity segregation and reverse segregation of Zn are effectively avoided.

The invention discloses a double-compensation interruption type anti-gravity pouring system and a pouring method for an aluminum alloy casting, and belongs to the technical field of metal casting. The pouring system comprises a cavity, a riser tube and a chilling block assembly, the cavity comprises a plurality of body sprues, a plurality of risers are arranged on the upper side of the cavity and right above the body sprues in a one-to-one correspondence mode, and a plurality of bottom plate sprues are arranged on the lower side of the cavity and right below the body sprues in a one-to-one correspondence mode. The riser tube is positioned below the cavity and communicates with the plurality of bottom plate sprues through the bottom plate cross gate, and the chilling block assembly divides the cavity into a plurality of areas. And in the pouring process, bidirectional metal liquid feeding is carried out on the body sprue through a dead head and the bottom plate sprue, the defects of looseness, bubbles, slag inclusion and insufficient pouring are avoided, and the qualified rate of products is greatly increased.

The invention discloses a casting method for improving the mechanical property of a large-size aluminum alloy wheel. The casting method is characterized by comprising the following steps that in the liquid lifting stage, aluminum liquid in a heat preservation furnace is lifted to the position near a sprue of a wheel mold; air cooling of the position, close to an inner rim, of an upper mold of thewheel mold is opened; a mold cavity is stably filled with aluminum liquid near the sprue in a mold filling stage; water cooling of the position, close to an outer rim, of a side mold of the wheel moldis opened; a rapid supercharging mode is adopted in a supercharging stage; pressure is maintained; when the solidification front edge is pushed to a spoke area of the wheel mold, water cooling and air cooling of the position, close to a spoke, of the upper mold are opened; cooling water at a diversion cone is opened; after the spoke portion completes solidification, water cooling at the position,close to a wheel boss, of a lower mold of a road mold is opened; and cooling is carried out, the mold is opened, and a casting is ejected out. Common R corner defects in low-pressure cast wheels canbe effectively eliminated, the mechanical properties of two key parts comprising the wheel boss and the spoke are remarkably improved, and the casting method is particularly suitable for producing large-size aluminum alloy wheels.

The invention provides a cooling process for foundry waste sand. The cooling process includes the following steps that hot sand coming from the drying procedure enters a cooling device with a stirring function through a sand inlet so as to be rolled and stirred; at the same time, a water-cooling spray device of a water cooling system on the top of a stirring barrel and a centrifugal fan of an air cooling system at the position of the sand inlet are started; cooling water generated through the steps mentioned above is collected in a water collection tank at the bottom of the cooling device and is circulated into a cooling pool through a pipeline pump; and the cooled sand enters the next procedure through a sand outlet after passing through a screening device. The cooling process is simple in structure, convenient to install and use and low in energy consumption, the water cooling system and the air cooling system exchange heat with materials at the same time, the heat exchange rate is high, the cooling effect is good, the dust removal and impurity removal effects are further achieved by additionally arranging the air cooling system, the cooling speed is easy to control, progressive solidification is achieved, the defect of shrinkage cavities is avoided, and the cooling process is widely applied to medium and small foundry enterprises.

The invention discloses a casting method for refining the structure of an investment casting. The casting method comprises the following steps: S1, preparing an investment shell (2); S2, heating the investment shell (2) to a preheating temperature and keeping at the same temperature; S3, covering the bottom of a water-cooling copper mold (4) with refractory sand (3), and after the investment shell (2) is transferred into the water-cooling copper mold (4), filling a gap between the investment shell (2) and the water-cooling copper mold (4) with the refractory sand (3); S4, pouring molten alloy liquid into the investment shell (2); S5, turning on a switch of a water inlet (5), adjusting the numerical value of a pressure gauge (6), and cooling the investment shell (2) until the temperature is reduced to the room temperature; and S6, transferring the investment shell (2) out of the water-cooling copper mold (4), cleaning the investment shell (2) and taking out a casting. According to the method, the structure of the precision investment casting is refined and the mechanical property is improved, sequential solidification of the casting can be achieved in a solidification process, and the internal quality of the casting is improved.

The invention provides a large complex rudder framework titanium alloy casting method, which comprises the following steps of: designing a bottom pouring type pouring system according to the structural characteristics of a rudder framework titanium alloy casting to be formed, penetrating a sprue from the top of the bottom pouring type pouring system to the bottom of the bottom pouring type pouringsystem, generating a graphite mold in a software differencing mode according to the bottom pouring type pouring system, enabling the graphite mold to enter a degassing furnace for degassing at normaltemperature, the vacuum degree of the degassing furnace being less than 3 Pa, assembling and combining the split graphite mold subjected to degassing, and putting the assembled graphite mold into a titanium alloy skull furnace, conducting vacuum pumping to melt a titanium alloy ingot, conducting casting forming, and generating a formed rudder framework titanium alloy casting. The method can meetthe production requirements of large complex rudder framework titanium alloy castings, and the internal quality and the percent of pass of the large complex rudder framework titanium alloy castings are improved.

The invention discloses a low-pressure casting method and device for a thin-wall complex aluminum alloy gearbox shell, and belongs to the technical field of automobile accessory manufacturing, the device comprises a dead head, a sand core, a sprue and a loose core, a cylindrical feeding channel is formed in the sand core, an inner runner is arranged on the sprue, the sprue and the sand core are connected through matching of the cylindrical feeding channel and the inner runner, and the loose core is arranged in the inner runner. The inner runner is communicated with a bolt column of a casting, the loose core is arranged on the outer side of the sprue and the outer side of the sand core, the loose core is connected with an external pushing hydraulic cylinder, and the upper die, the lower die, the loose core and the sand core jointly form a forming die of the casting. The flange bolt boss adopts the comprehensive means of riser feeding, sequential solidification of castings in the low-pressure casting process is achieved, and the problems that the wall thicknesses of the castings are greatly different, the structure is complex, and poor forming and shrinkage porosity of products are prone to occurring are solved.

The invention relates to a casting process for a rocker arm shell of an extra-thick coal seam coal mining machine, which is characterized in that a plane passing through the axis of a motor cylinder and the axis of a planet head mounting cylinder of the rocker arm shell of the coal mining machine is used as a parting surface, a sand box molding casting mode combining a real sample mold and a core assembly is adopted, and a sand mold outer mold and a loam core are made of resin sand; a casting water channel part, a round corner part and a corner on a loam core are made of chromite sand, an open bottom return type pouring system and a horizontal pouring mode are adopted, the pouring system is completely made of ceramic pipes, an open riser is arranged at each of a planet head mounting cylinder and a motor cylinder, an open riser is arranged at the joint of the motor cylinder and an arm support, and an open riser is arranged at the joint of the motor cylinder and the arm support. Four blind risers are arranged on the upper plane of the arm support and on the edge close to the coal wall side at intervals, two blind risers are arranged on the upper plane of the arm support and on the edge close to the goaf side at intervals, and a plurality of external chillers are arranged at the bottom of the lower box. According to the invention, many casting defects can be avoided, the production period is shortened, and the casting quality and the production efficiency are improved.