31results about How to "Reduce inclusion defects" patented technology

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 process for discharging wax liquid in the process of dewaxing a precise casting mould shell without residual wax liquid, which comprises the following steps: (1) after an assembling mode of a wax piece is determined, the lowest point where the wax liquid is difficult to flow out when the wax piece is dewaxed on a die set is determined, and then a wax-discharging channel is pre-designed at the lowest point when a wax mould is designed, wherein one end of the wax-discharging channel is connected with the lowest point of a wax mould, while the other end is connected with an internal pouring channel or a main pouring channel in the wax mould, and the distance between the contact point of the wax-discharging channel and the internal pouring channel or the main pouring channel and a pouring basin in the vertical direction is smaller than the distance between the lowest point and the pouring basin; (2) the slurrying, sanding, and drying are performed on the wax mould layer by layer; (3) dewaxing is performed; and (4) a mould shell is poured, wherein after a cast product is formed, residual metals formed on the wax-discharging channel are cut away. The process has the advantages of not only reducing the wax material consumption and reducing the cost obviously, but also reducing the defects of slag inclusion and impurity inclusion for the cast product, improving the quality of the cast product, having good use effect, consuming few wax materials and the like.

The invention relates to a steady casting technique for inhibiting liquid level fluctuation of a continuous casting crystallizer, and belongs to the technical field of continuous casting techniques inthe metallurgical industry. According to the technical scheme, the technique comprises steps as follows: A. controlling the interference amplitude in the fluctuation superposition frequency range produced by unstable crystallizer liquid level to be the lowest; B, controlling fluctuation in the low frequency range caused by unstable bulging of a casting blank; (3) improving the equipment precisionof the head of a continuous casting machine; (4) using a novel efficient double-hole nozzle or a novel pulse-controlled nozzle. The technique has the beneficial effects that the defect of subsurfaceinclusion of casting blanks due to slag entrapment of molten steel in a crystallizer is greatly reduced, and surface quality of a final product is improved; malignant production accidents such as continuous casting breakout caused by poor lubrication of crystallizer casting powder and uneven initial blank shell of the crystallizer are greatly reduced.

The invention discloses a blowing-suction integrated cleaning device for an aviation blade and a complex component mold shell. The blowing-suction integrated cleaning device is composed of a vortex inlet mechanism (1), a gas loop control mechanism (2), a blowing-suction head tube (3) and a blowing-suction mouth head (4); the blowing-suction head tube (3) is provided with two parallel gas circuitswhich are the main gas circuit and the branch gas circuit; the blowing-suction mouth head (4), the tubular main gas circuit in the blowing-suction head tube (3) and the vortex inlet mechanism (1) arecoaxially and sequentially connected; and the gas loop control mechanism (2) is simultaneously connected with the branch gas circuit of the blowing-suction head tube (3) and the vortex inlet mechanism(1). The invention further discloses a blowing-suction integrated cleaning method for protecting the aviation blade and the complex component mold shell. According to the blowing-suction integrated cleaning device and method, the percent of pass of casting can be effectively improved, and the blowing-suction integrated cleaning device and method have predictable huge economic value and social value.

A hollow circle cast ingot hot top casting device and a method of manufacturing a hollow tubular product relate to a device and a method used in casting thin-walled hollow tube. The device consists of an overcoat, a mandrel support, a core and a continuous processing machine of core hot top, a core graphite set, a condensate tank, a hot top of condensate tank and a graphite bush of condensate tank, a core intake pipe, a water outlet, a water inlet tank, a water outlet of condensate tank an a dummy ingot. The manufacture method is: high-temperature aluminum alloy liquid flows from an opening of the hot top of condensate tank and the core hot top and is cooled by cooling water in the core and the condensate tank. The dummy ingot is driven by a semicontinuous casting machine and moves down at a steady speed, thereby making the liquid steadily flow into a crystalline belt in which the liquid crystallizes slowly to form an ingot tube. Surface segregation aliquation float of thin-walled hollow tube manufactured by the present invention is less than 1mm. A crystal grain with few air holes and inclusion defects is small. Grain size is up to the first grade and metal plasticity is improved, which is favorable for processing and able to reduce cost. Moreover, the present invention is able to create good environment for operation and produce little environmental pollution.

The invention provides a design method of a duplex directional hollow blade casting system. The method comprises the steps: combining casting systems; manufacturing a mold shell of a wax mold module;and putting the mold shell into a three-chamber vacuum furnace to complete casting, wherein the casting temperature of a casting piece is 1480 DEG C, and the crystal pulling speed is 4 mm / min. The combination of the casting systems specifically comprises the steps of determining the diameter of a module chassis; determining the process epitaxy of blades; determining the position of the starting section on the module chassis; determining the height of a middle straight pipe of the module; connecting a casting system mold filling path; arranging a cross gate connected with the middle straight pipe and a pouring cup; and connecting the pouring cup to the upper portion of the middle straight pipe. By designing and optimizing the combination mode of the casting system, the problems of metallurgical defects such as broken crystals, oblique crystals and exposed crystals of columnar crystals at the position of an exhaust edge are successfully solved, and deformation of casting pieces in the casting process is effectively controlled.

The invention provides a tundish covering flux, a preparation of the tundish covering flux and an application method of the tundish covering flux. The tundish covering flux comprises, by weight percentage, 1.5-4.5 % of metal aluminum powder, 1.25-2.2 % calcium powder and 93-97% low-melting-point premelting slag. The preparation of the tundish covering flux is characterized by placing the metal aluminum powder, the calcium powder and the low-melting-point premelting slag which are extracted according to a ratio into a vertical type mixer for mixing for 1-3 hours; and placing the evenly-mixed covering flux mixture in a drying oven, and drying for 1-4 hours in nitrogen protective atmosphere and at a temperature of 50-70 DEG C. The application method of the tundish covering flux is characterized by respectively adding the covering flux at 0.1-0.2 kg per ton of steel after the pouring of a first pot of steel in casting is started and when the pouring of the first pot of steel is finished; and respectively adding the covering flux at 0.05-0.1 kg per ton of steel at the beginning of the pouring of every pot and at the end of the pouring of every pot. According to the tundish covering flux, the preparation of the tundish covering flux and the application method of the tundish covering flux, oxygen and nitrogen in the molten iron are reduced remarkably, the removal rate of ferrous oxide in steel reaches 11.49 %, the T.O reduction rate reaches more than 15%, the nitrogen reduction rate reaches 20%, therefore, the inclusion defect of a slab is greatly reduced, the inherent quality of rolled plate coil is improved, and the quality objection is avoided.

The invention discloses a lift tube in low pressure casting. The lift tube in the low pressure casting comprises an outer tube and an inner tube, wherein the outer tube and the inner tube are concentrically arranged, a silicon carbide thin film is arranged on the inner wall of the inner tube, a damper which is fixedly connected with the lift tube is arranged at the inlet position of the lift tube, and a plurality of small holes are evenly formed in the side face of the damper. According to the lift tube in the low pressure casting, metal splashing in pouring and impact agitation of remained metal at the bottom of a crucible are reduced, inclusion defects are gradually overcome, casting quality is obviously improved, meanwhile the lift tube has expected intensity, good bearing ability and abrasion resistance due to the fact that structure of concentrically arrangement of a metal tube and a non-metal tube is adopted, and moreover unexpected chemical reaction between the metal tube and molten metal is effectively prevented from happening due to the fact that the silicon carbide thin film and a fire-resistant cement tube can well prevent the molten metal from being immersed into the metal tube.

The invention relates to the field of shell type preparation of investment casting, in particular to a surface layer shell type preparation method capable of effectively improving a small-size concaveprofile rising. The preparation method comprises the following steps that a coating is prepared, specifically, a first coating is prepared, specifically, 1 part of silica sol, 0.5-1 part of water, 2.5-3.5 parts of an aggregate, 0.001-0.005 parts of a wetting agent in part by weight are prepared, sequentially added into a first batching barrel, and uniformly stirred to form the first coating; a second coating is prepared, specifically, 1 part of the silica sol, and 2.5-3.5 parts of the aggregate in part by weight are prepared, sequentially added into a second batching barrel, and uniformly stirred to form the second coating; a wax mold is pre-coated; and shell manufacturing is carried out. The first coating with low viscosity and low surface tension is used for pre-coating and treating thewax mold, so that a wet pre-coating layer is formed between a surface layer coating and the wax mold, the direct contact between the surface layer coating and the wax mold is avoided, the phenomenonof the bubble accumulation on the small-size concave profile of the wax mold due to the oversized surface tension of the surface layer coating can be avoided, and the rising of a casting is effectively reduced.

The invention provides a preparation and application method of a molten steel covering flux. Raw material ingredients of the molten steel covering flux comprise 5-40% of CaO, 26-60% of SiO2, 4-8% of MgO, 5-11% of Al2O3, 3-6% of Fe2O3, 0-20% of solid C, less than or equal to 0.10% of S, and less than or equal to 0.5% of H2O. The melting point is 1200-1360 DEG C. The melting speed is 70-100 s<-1>. The volume density is 0.8+ / -0.2 g / cm<3>. Raw materials are blended in a blender for 1-3 h and then are subjected to low-temperature drying treatment in a nitrogen protective atmosphere after being blended evenly. The drying temperature is 50-70 DEG C. The drying time is 1-4 h. The covering flux is directly added to the surface of molten steel in a molten steel tank after tapping of molten steel or directly added to the surface of molten steel in a continuous casting tundish. The addition quantity of the covering flux is 0.7-1 kg in each ton of steel. By means of the method, oxygen and nitrogen in molten steel can be remarkably decreased, so that inclusion defects of casting blanks are reduced, and the quality of the casting blanks is improved. Meanwhile, dust pollution is effectively reduced, and the field operating environment is improved.

The invention provides a refining method for molten steel. The method comprises the step of firstly refining the molten steel, a modifier and refining slag, thereby acquiring the refined molten steel.The modifier comprises alloy tailings prepared through the thermite process or the alloy tailings prepared through the thermite process and Al2O3. According to the method, the tailings are selected from the wastes difficult to be treated and the tailings generated from the waste alloy prepared through the thermite process are used for refining the molten steel, so that the top residue of the steel ladle is modified, the capability of the slag for adsorbing the impurities is improved and the recycling of the solid wastes is realized. Meanwhile, the refining method adopts a simple process, no additional production equipment is required, the condition is reasonable and the method is suitable for large-scale industrial production.

The invention discloses a bottom pouring type purification smelting device and method, and belongs to the technical field of casting. The smelting device comprises an annular bottom argon blowing device and a bottom pouring device; the bottom argon blowing device is arranged at the bottom of a pouring ladle or a crucible, the upper end of the bottom argon blowing device is detachably connected with the bottom of the pouring ladle or the crucible, the bottom end of the bottom argon blowing device is connected with an argon feeding pipe, argon enters alloy liquid in the pouring ladle or the crucible from the argon feeding pipe through the bottom argon blowing device, and the alloy liquid is purified; and the bottom pouring device is a rod-like pulling device which is inlaid in a middle through hole of the bottom argon blowing device or a plate-like pulling device which is arranged below the bottom argon blowing device. When the smelting device is used, the argon is fed into melt to purify the melt through the bottom argon blowing device, then, the bottom pouring device is moved downwards or removed for bottom pouring type pouring. Through the bottom pouring type purification smeltingdevice and method, the bottom argon blowing and bottom pouring functions can be achieved at the same time, the alloy liquid can be purified better, and accordingly, the quality of the alloy liquid isimproved.

The invention discloses a preparation method for a low-alloyed high-strength plastic magnesium alloy material, and relates to a preparation method for a magnesium alloy material, and aims to solve thetechnical problems that an existing magnesium alloy material is too high in cost, cannot simultaneously guarantee strength and plasticity, and is great in high-temperature deformation energy consumption. A way of combining low alloying with low-temperature upsetting and squeezing deformation thermal treatment can be adopted to improve mechanical property of a magnesium alloy. Low-content zinc andyttrium can be added, so that solution strengthening and grain refining effect is generated in a magnesium matrix; the solution strengthening and grain refining effect is combined with the low-temperature upsetting and squeezing deformation thermal treatment, so that the magnesium alloy can generate more diffuse precipitated phases while grain refining is generated in a deformation process, and the generated diffuse strengthening effect guarantees that strength and plasticity of the magnesium alloy material are greatly improved. Low-content alloy elements are added, and low-temperature upsetting and squeezing thermal treatment is adopted, so that processes are simplified, production cost can be greatly reduced, and market competitiveness of the alloy is improved. The preparation method isused for preparing the magnesium alloy.

The invention discloses a welding method capable of reducing inclusion defects in medium-thickness plate weld joints. The welding method comprises the steps that welding is conducted in a groove to form the weld joints, cleaning laser is synchronously started for cleaning after each weld joint is formed, and metal colors of the weld joints are exposed. For a V-shaped groove, continuous laser and MIG hybrid welding is adopted for welding in the first welding process to form the weld joints, laser cleaning is synchronously conducted after welding, and then the first welding process and cleaningare repeatedly conducted. For a Y-shaped opening, the first welding process adopts continuous laser for welding to form the weld joints, laser cleaning is synchronously carried out, and then a secondwelding process is carried out on the surface of the first weld joint, continuous laser and MIG hybrid welding is adopted for welding, laser cleaning is synchronously carried out after welding, and then the second welding process and cleaning are repeated. An oxidation film formed by each weld joint can be effectively cleaned, the welding efficiency can be effectively improved, and the welding quality is improved.

The invention discloses an adhesive for casting and a preparation method of the adhesive. The adhesive for the casting and the preparation method of the adhesive mainly aim at hybrid modification of a zirconium diacetate adhesive in the field of casting titanium, zirconium, namely alloys thereof, especially resolubility improvement of the zirconium diacetate adhesive, and acid latex, acrylic emulsion and vinyl acetate emulsion are added into the zirconium diacetate adhesive to perform the hybrid modification on the zirconium diacetate adhesive, so that the redissolution resistance of the adhesive is improved. The redissolution problem in the shell manufacturing process is eliminated, and the surface coating falling caused by shell redissolution and inclusion defects generated by surface precipitates are reduced.

The invention discloses a method for casting a super-large type semi-gear ring. An outer rim whole ring open riser and an insulating riser sleeve, inner circle allowance, and external circle chilling block chilling are adopted; and circular insulating blind risers are dispersed on an inner rim and the corresponding bottom is chilled by the chilling block correspondingly so as to obtain semi-gear ring blank. In the method for casting the super-large type semi-gear ring, the outer rim whole ring open riser and the insulating riser sleeve are adopted, so that the feeding capacity of the riser isenhanced and the tissue compactness of the prepared casting is obviously improved, simultaneously floating sand and sundries can float conveniently, and the defects of sand inclusion, air holes and inclusion are reduced; the whole ring inner allowance and sand lining chilling block chilling are adopted; the inner allowance can ensure that an outer rim wall thickness center moves inward; by sand lining chilling block chilling, the tissues of the gear surface and the gear root are densified, and the defect of magnaflux inspection is reduced; and the inner allowance is not removed during furtherprocessing, the blank gear surface quality of the semi-gear ring is guaranteed, and the gear surface magnetic powder and ultrasonic flaw detection yield is improved.

The invention relates to the preparation field of steel ingots, and particularly relates to a plasma submerged arc heating method of 5 to 600-ton steel ingot riser. The method comprises the step of heating a riser after pouring a large-scale steel ingot so as to increase the heat of the riser, strengthen the feeding of the riser and improve the quality of the steel ingot; the method is suitable for plasma submerged arc heating of the riser after the steel ingot is poured, tundish plasma submerged arc heating of other alloys and submerged arc plasma heating in a smelting process. The riser of the large-scale steel ingot is heated by a plasma submerged arc heating gun; the pouring temperature and the pouring speed of the steel ingot, the plasma submerged arc heating time and the argon introducing amount are strictly controlled; the negative segregation of the steel ingot is controlled by heating the steel ingot immediately after the steel ingot is poured; the feeding of the riser is strengthened by heating the riser and rapidly building a positive temperature gradient; the loosen defect of the steel ingot contraction cavities are reduced and the defect is controlled at a first level; foreign matters can float up rapidly by the stirring function of the argon; and the total amount of foreign matters in the steel ingots is controlled to be less than or equal to a second level.

The invention discloses a directional solidification device, in particular discloses a directional solidification device and a process method for improving single crystal blade deposits, and belongs to the technical field of single crystal casting process equipment design and manufacture. Provided are a directional solidification device and a process method for improving single crystal blade deposits which can effectively improve crystal selection quality and reduce or reduce deposition of trace components. The directional solidification device includes a water cooling plate and a crystal selector arranged at the bottom of the mold shell, the bottom of the crystal selector is seated on the water cooling plate, and the directional solidification device also includes an air film isolation system, and the water cooling plate A gas film isolation layer is formed between the crystal selector and the inert gas output by the gas film isolation system. The process method adopts firstly passing gas through a gas film isolation system to form a gas film isolation layer, and then performing pouring, drawing, cooling and solidification of the single crystal blade.

The invention relates to the field of shell mold preparation of investment casting, in particular to a surface shell mold preparation method that can effectively improve small-sized concave surface casting nodules, comprising the following steps: coating preparation: preparing the first coating: parts by weight Prepare 1 part of silica sol, 0.5 to 1 part of water, 2.5 to 3.5 parts of aggregate, 0.001 to 0.005 parts of wetting agent, and add them to the first batching tank in turn, stir evenly to form the first coating; prepare the second coating: press Prepare 1 part of silica sol and 2.5 to 3.5 parts of aggregate in parts by weight, and add them into the second batching bucket in turn, stir evenly to form the second coating; pre-coat the wax model; and make the shell. By using the first paint with low viscosity and low surface tension to pre-coat the wax pattern, a wet pre-coat layer is formed between the top coat and the wax pattern, avoiding direct contact between the top coat and the wax pattern, and can Avoiding the accumulation of air bubbles on the small-sized concave surface of the wax mold caused by excessive surface tension of the surface coating, effectively reducing casting nodules.

The invention relates to a mold shell and tool connecting method in spin force casting. The method comprises the steps of mold shell shaping, assembly step, adhesive mixing, joint patching and moduleheating. Bauxite is used as materials in adhesives, so that a cast mold shell and a casting tool are stably combined; and meanwhile, a steel tile tool is prevented, so that the defect problems of casting looseness and slag inclusion in the spin force casting process are solved.

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 side edge sand core provided with a dispersion pouring system. The side edge sand core comprises a sand core body, the pouring system is arranged on the sand core body, and the pouring system comprises a sprue, a runner and an ingate; and the side edge sand core is characterized in that the sand core body is divided into a main sand core body and a runner-ingate sand corehead along the central axis surface of the runner, and the runner and the ingate in the pouring system are located on the runner-ingate sand core head.

The invention discloses a side edge sand core provided with a dispersion pouring system. The side edge sand core comprises a sand core body, the pouring system is arranged on the sand core body, and the pouring system comprises a sprue, a runner and an ingate; and the side edge sand core is characterized in that the sand core body is divided into a main sand core body and a runner-ingate sand corehead along the central axis surface of the runner, and the runner and the ingate in the pouring system are located on the runner-ingate sand core head.

The invention relates to a steady-state casting process method for suppressing liquid level fluctuations in a continuous casting crystallizer, and belongs to the technical field of continuous casting processes in the metallurgical industry. The technical solution of the present invention is: A. controlling the fluctuation in the superimposed frequency range caused by the instability of the crystallizer liquid level has the lowest interference amplitude; B. controlling the fluctuation in the low frequency range caused by the unsteady bulge of the slab; (3) improving the continuous The equipment accuracy of the head of the casting machine; (4) Use new high-efficiency double-jet nozzles or new pulse control nozzles. The beneficial effects of the present invention are: greatly reducing the subcutaneous inclusion defects of the cast slab caused by molten steel slag rolling in the crystallizer, improving the surface quality of the final product; greatly reducing the poor lubrication of the mold mold slag and the uneven shell of the mold primary slab Vicious production accidents such as continuous casting breakouts caused.

The invention provides a design method of a pouring system for double directional hollow blades. Including: the combination of pouring system; the manufacture of the shell for the wax pattern module; the shell is placed in a three-chamber vacuum furnace to complete the pouring. The casting temperature is 1480°C and the crystal pulling speed is 4mm / min. Among them, the combination of the gating system specifically includes: establishing the diameter of the module chassis; determining the process extension of the blade; determining the position of the starting section on the module chassis; determining the height of the straight pipe in the module; connecting the filling path of the gating system; Set up runners connected with the straight pipe and sprue cup; connect the sprue cup above the straight pipe; through the design optimization of the combination of the gating system, the broken crystal of the columnar crystal at the exhaust side, Metallurgical defects such as oblique crystals and outcropping crystals, and effectively control the deformation of castings during pouring.

The invention discloses a preparation method of rare earth nano high-strength titanium. The preparation method comprises the following steps of adding rare earth yttrium into pure titanium, smelting in vacuum, and carrying out primary forging, secondary forging and heat treatment to obtain the rare earth nano high-strength titanium. According to the preparation method, the advantages of metal ultra-fine grains and nanocrystalline are effectively combined through the mechanisms of rare earth refining as-cast structure, rare earth phase strengthening high-temperature performance, severe plastic deformation and the like, and the rare earth nano high-strength titanium material of submicron and nanocrystalline scales is successfully prepared through medium-low temperature rapid large-deformation forging and low-temperature annealing processes. The preparation method is simple in process, low in investment, high in efficiency and good in effect.