136results about How to "Avoid Casting Defects" patented technology

The invention discloses a method for preparing a composite pipe by expanding a secondary pouring dual-metal pipe billet. The secondary pouring dual-metal pipe billet is manufactured by the following steps: by adopting an evaporative pattern casting process, pouring to obtain an inner-layer thin-walled high-alloy corrosion-resistant pipe billet, and by adopting a sand casting method, pouring to obtain an outer-layer carbon steel pipe billet, thereby obtaining the dual-metal pipe billet. The expanding process is characterized by comprising the following steps: by adopting the dual-metal pipe billet prepared by secondary pouring, performing three-roller hot-rolling expanding deformation, thereby obtaining the dual-metal composite pipe. According to fusion of the inner and outer layers of metals in the casting process and plastic deformation in the hot-rolling expanding process, the dual-metal composite pipe with good metallurgical bonding property can be obtained. According to the dual-metal composite pipe disclosed by the invention, the high-precision inner-layer metal surface is obtained by virtue of the evaporative pattern casting process, and the inner-layer metal thickness is controllable; and moreover, due to the three-roller hot-rolling expanding process, high-strength metallurgical bonding among the inner and outer layers of metals is realized, the inner-layer surface precision is high, the ellipticity is high, and the wall thickness precision is high.

The invention discloses a dual-compound wear-resisting hammer comprising a hammer handle and a hammer body; the hammer body is formed by compound casting of two kinds of metal liquids, and the hammer body is in casting connection with the solid hammer handle to form the hammer. The manufacturing method includes the following steps: step 1, manufacturing and casting a sand mold according to a structure of the hammer; step 2, processing the hammer handle with a low-alloy steel blank material, and preburying one end of the hammer handle into the casted sand mold of the hammer; step 3, selecting high-chromium cast iron and carbon steel, and carrying out quantitative pouring in sequence; and step 4, carrying out heat treatment. The dual-compound wear-resisting hammer not only can improve wear resistance of the hammer but also allows the hammer body and the hammer handle to be combined closely and not generate cracks, casting defects are overcome, the product yield is improved, the cleaning workload is reduced, and the quality and the service life of the hammer are improved substantially.

The invention relates to a method for preparing a single-crystal copper bonding wire, which uses copper as a raw material. The method comprises the following steps: melting high purity copper of which the purity is higher than 99.995 percent by using a high-vacuum furnace, raising the temperature to between 1,100 and 1,180 DEG C, refining the copper for 60 to 120 minutes, and adopting high purity argon for protection in the whole melting process; broaching single-crystal copper rods of phi 4 to phi 8 mm in a directional solidification mode, and then coldworking the single-crystal copper rods to between phi 0.95 and phi 1.102 mm with the broaching working rate of 15 to 25 percent for each gate; broaching the single-crystal copper rods to between 0.020 and 0.05 mm with 47 to 70 gates and the working rate of 7.59 to 17.82 percent for each gate; and carrying out sonicleaning on the surface of the single-crystal copper bonding wire when the wiredrawing temperature is between 35 and 45 DEG C, carrying out heat treatment on the cleaned single-crystal copper bonding wire, and using H2+Ar2 for protection with the temperature of between 410 and 425 DEG C, the time of between 0.7 and 2.0s and the annealing rewinding tension of between 0.6 and 2.8g.

The invention provides a low-power radial welding bogie comprising two wheel sets, a three-piece side welding beam and a crossbeam. Two ends of the side beam are connected with the wheel sets through primary rubber-metal pads and bearing saddles respectively. The wheel sets are connected with a wheel set connecting device through the bearing saddles. A crossbeam assembly is connected with the side beam through two secondary suspension systems. A foundation brake gear is suspended on the crossbeam assembly or the side beam. The secondary suspension systems have multiple structural styles, and the wheel sets are of variable- gauge structures. Compared with conventional freight car bogies, the low-power radial welding bogie has the advantages that the bogie is good in uniform load performance; defects of cast structure swing bolsters and side frame casting are avoided; wheeltrack acting force is reduced, and wear parts of the suspension systems are reduced; the variable-gauge wheel sets meet requirements on variable-gauge performance of the bogie; high-speed operation stability of the bogie is improved, and rim wear generated when the bogie passes curves is reduced; the bogie can meet the requirements on maximum axle load of 30t and highest running speed of 200km/h.

The invention discloses a preparation method for a high-strength wear-resistant alloy Cu-15Ni-8Sn. The process comprises the following steps: adding electrolytic copper and nickel; pouring the electrolytic copper and nickel in an intermediate-frequency coreless induction furnace; adding charcoal; charging nitrogen gas with one barometric pressure; melting; melting for 30-65 minutes at 1300-1350 DEG C; adding tin and melting at 1250-1300 DEG C; adding a refiner and a deoxidizer; stirring; adding a grain refiner; adding a modifier; slagging off; carrying out inspection before melting; carrying out electromagnetic casting after ingredients are qualified; cutting a head and a tail; scalping; carrying out ingredient inspection after melting; carrying out organization structure analysis; and carrying out performance detection. A Cu-15Ni-8SnC72900 alloy melt and cast by virtue of the intermediate-frequency coreless induction furnace, which is obtained by the preparation method disclosed by the invention, is low in production cost; and the developed products are high in quality. The developed products can be applied to national defense and military industry, ocean engineering and high-end preparation manufacturing industry; and the increasingly urgent needs of the national defense and military industry, ocean engineering and high-end preparation manufacturing industry on high-performance copper alloy materials are met.

The invention discloses a single crystal copper bonding lead and a preparation method thereof, relating to the field of production of microelectronic materials. The production technology integrates a metal material preparation process, a heat treatment process and a diamond die process, ensures the production consistency and reliability and realizes the large-scale production. The adopted production process comprises the steps of providing die repair and gas protection equipment, smelting, wiredrawing, cleaning, and compounding, packaging and testing a finished product. The single crystal copper bonding lead has the beneficial effects that as a signal crystal copper material has a compact solidification structure, lateral crystal boundaries are eliminated, the casting defects of shrinkage cavities, pores and the like are avoided, the plastic working performance, the mechanical performance, the electric performance and the like of the signal crystal copper material are obviously higher than those of the conventional oxygen-free copper, the defects of more end breakage, low quality and low productivity in the wiredrawing process of the conventional copper wire are overcome, and an electronic packaging bonding wire with the wire diameter reaching 0.015m, high strength, high elongation and stable performance can be prepared.

The invention relates to a novel aluminum alloy; the content of Si in the aluminum alloy is adjusted, based on the aluminum alloy A356.2; the chemical components thereof are as follows: larger than 7.5 to 8.2 percent of Si, 0.28 to 0.45 percent of Mg, 0.08 to 0.20 percent of Ti, not larger than 0.12 percent of Fe, not larger than 0.01 percent of Cu, not larger than 0.01 percent of Zn, not larger than 0.05 percent of Mn, not larger than 0.05 percent of Zr, not larger than 0.01 percent of Ni, not larger than 0.01 percent of Sn, not larger than 0.10 percent of microelements and the rest is Al. In the invention, as the content of Si in the aluminum alloy is properly added, the novel aluminum alloy can optimize the matching between the anti-tension intensity and the extending rate of the aluminum alloy, increase the anti-impact performance of the product and simultaneously improve the casting fluidity of the aluminum alloy and effectively reduce the casting defect; therefore, the novel aluminum alloy has the characteristics of optimizing the matching between the anti-tension intensity and the extending rate of the aluminum alloy, increasing the anti-impact performance of the product, improving the casting fluidity, avoiding casting defect, improving the product quality, and the like.

The invention relates to a high texture magnesium alloy surface treatment method and a product thereof. The method comprises: (1) die casting forming of a magnesium alloy work-piece; (2) a surface pre-treatment; (3) a formation treatment; (4) cold spray coating; and (5) an electrophoresis coating treatment. The product is the product produced through treatments by using the method. According to the present invention, the product with the high texture appearance can be produced on the magnesium alloy die casting surface, the method has characteristics of environmental protection process, simple process and substantial magnesium alloy die casting finished product yield increase, and is suitable for large scale industrial application, and the treated product has characteristics of good corrosion resistance, compactness, beautiful appearance, changeable color, metal effect and metal color penetration effect.

Disclosed is an internal top-mounting type super-high pressure super-low temperature hard sealing ball valve, which is mainly composed of a valve body (1), a valve cover (24), a ball body with a handle (3), a valve seat (13), a rear valve seat (10), a valve rod bearing seat (16) and the like. The ball body with a handle (3) placed in the valve body (1) penetrates through the center of the valve cover (24), and the ball body with a handle (3) is enabled to rotate 90 degrees by an external force to realize the opening and the closing of pipes. The sphere sealing is realized by that two sides of the ball body with a handle (3) hold the rear valve seat (10) and the valve seat (13), and a valve seat spring (12) elastically pushes and presses the ball body with a handle (3). The sealing of a valve rod employs a unique three-ply sealing structure of a self-sealing preloading device, which can guarantee sealing under low pressure, and under the action of high pressure, medium pressure action realizes self-sealing for a bearing ring (17), thereby avoiding that filling material sealing needs the high-strength pressure, and the torque becomes extremely large when the valve rod is opened.

The invention belongs to the technical field of bonding gold wire processing, in particular to a 4N bonding gold wire capable of being processed to phi 6 micrometers through wire drawing and a preparation method of the 4N bonding gold wire. The 4N bonding gold wire comprises gold and an alloy additive. The alloy additive is formed by copper, vanadium, magnesium, palladium, silver, nickel, bismuth,beryllium, cerium, zinc, yttrium, calcium, gadolinium, aluminum and lead. According to the prepared bonding gold wire, the alloy additive of the specific components and content is added, the drawingstrength of the gold wire can be improved through the alloy additive, and the radian of the bonding gold wire can be reduced; the prepared bonding gold wire has the good low and long radian through adding of the additive and the reasonable proportion while guaranteeing high strength; the prepared gold wire has good drawing strength, heat conductivity, resistance and low and long arc length; and meanwhile, axial long crystals are formed after a single-crystal continuous casting method is adopted for casting, high purity and a continuous columnar crystal structure are achieved, a transverse crystal boundary is eliminated, casting defects are avoided, and the prepared gold wire can be processed to 6 micrometers.

The invention relates to a production method of a 2507 stainless steel pump casting. The method includes (1) die designing and manufacturing, (2) moulding and core manufacturing, (3) paint brushing, (4) sand mould and sand core drying, (5) mould assembling, (6) smelting, (7) pouring, (8) mould disassembling and sand removing, (9) gate and riser removing, (10) repair welding, and (11) polishing andshot blasting. Through a reasonable casting process design, casting defects including air holes, oxide slag inclusion and cracks are prevented, the repair rate and the rejection rate of casting are reduced, product quality is ensured, subsequent repair welding is greatly reduced, and the production cost of the casting is reduced.

The invention discloses a production technology for a casting zinc alloy water faucet. The technology comprises the following steps: A, forming a zinc alloy water faucet body by using gravity casting;B, performing shot-blasting sand-blasting pretreatment on the zinc alloy water faucet body; C, performing cavity wall sealing treatment on the zinc alloy water faucet body; and D, performing surfaceplating-coating treatment on the zinc alloy water faucet body, wherein a technology of the cavity wall sealing treatment in the step C comprises the following steps: C1) mixing powder: enabling dry organosilicon epoxy resin powder to be mixed with dry air, after adequately mixing, sending to a powder spray gun; C2) spraying powder: enabling a powder spray pipe of the powder spray gun to be slowlyinserted in a cavity of a casting body, beginning spraying the powder, enabling the powder spray pipe to be reversely and slowly withdrawn along the cavity of the casting body, after the powder spraypipe is completely withdrawn, stopping spraying the powder; and C3) roasting: placing the sprayed coasting body in an oven for roasting, after roasting, cooling and taking out the casting body.

The invention discloses a preparation method for a bimetal metallurgy composite pipe of a three-layer structure. The method includes the steps that firstly, a thin-walled high alloy anti-corrosion pipe blank on the inner layer and a thin-walled high alloy anti-corrosion pipe blank on the outer layer are prepared through pouring according to a lost foam casting method; then, an interlayer carbon steel pipe blank is prepared through pouring and EPS modeling with the high alloy pipe blanks on the inner layer and the outer layer as mold cores, and a stainless steel/carbon steel/stainless steel bimetal composite pipe blank of a three-layer structure is obtained; and the bimetal composite pipe of the three-layer structure is manufactured by conducting three-roller hot rolling expanding deformation on the obtained bimetal pipe blank of the three-layer structure. The high-accuracy metal surfaces on the inner layer and the outer layer are obtained according to the lost foam casting method, and the metal thickness of the inner layer and the outer layer can be controlled. The resistance to three-roller hot rolling expanding deformation is small. The three layers of metal are combined through high-strength metallurgy. The surfaces on the inner layer and the outer layer are high in accuracy, good in ovality and high in wall thickness accuracy.

The invention discloses a casting method of a large-area thin-wall part. The casting method includes the following steps of S1, preparing of silica sol coating; S2, slurry pasting, wherein a wax moldwith the shape the same as that of the large-area thin-wall part is soaked in the silica sol coating, and the surface of the wax mold is wet by the silica sol coating; S3, sand hanging, wherein aftersand grains are evenly attached to the coating on the surface of the wax mold,drying is carried out; S4, repeating of S2 and S3, wherein multiple times of slurry pasting and sand hanging are carried out, and a multi-layer mold shell is prepared; S5, dewaxing, wherein the mold shell is obtained; S6, roasting of the mold shell; and S7, casting and then natural cooling, wherein the large-area thin-wall part is obtained after mold release. When the large-area thin-wall part is cast, casting process parameters are improved, when the large-area thin-wall part is cast through precision casting, a heat mould gravity casting manner wide in application range is used, string breaking generated in the casting process is avoided, the casting defects of shrinkage porosity and cavities can be overcome, the percent of pass of casting products is increased, and the casting cost of the large-area thin-wall part is reduced.

The invention discloses a main oil duct sand core of a diesel engine frame and a manufacturing method thereof. The main oil duct sand core comprises a main core body and a main oil duct sand core bodyarranged on the main core body; the main oil duct sand core body is divided into a plurality of oil duct sand core subsections with the center of each gear of crank as the parting surface according to the number of cylinder bodies of the diesel engine frame; each oil duct sand core subsection is composed of a core rod and a sand body wrapping the core rod; positioning core heads are arranged at one ends of the oil duct sand core subsections, and positioning core grooves are formed in the other ends of the oil duct sand core subsections; the positioning core heads of the front oil duct sand core subsections are inlaid in the positioning core grooves of the rear oil duct sand core subsections for connection; and the main oil duct sand core further comprises two side core heads arranged at the front and rear ends of the multiple connected oil duct sand core subsections. Through the sectioning casting technology of the main oil duct sand core, the perpendicularity and concentricity of a main oil duct are guaranteed, and the casting defect of leaking in pressure testing is overcome thoroughly.

The invention discloses a calendaring roller shell and a manufacturing method of the calendaring roller shell. The calendaring roller shell is made of forged steel. The manufacturing method of the calendaring roller shell comprises the steps of roller blank preparation, thermal refining, surface quenching treatment, tempering treatment and final machining treatment. A line-frequency induction quenching method is adopted by surface quenching treatment. The quenching temperature is 890 DEG C-910 DEG C, the heating width of a line-frequency induction ring is 80mm-100mm, and the walking speed of the line-frequency induction ring is 0.8mm/s-1.2mm/s. According to the calendaring roller shell, cast iron is replaced by the forged steel and a special surface quenching technology is combined, so that the hardness of the surface of the finally machined calendaring roller shell reaches 82 HSD-88HSD, the uniformity of hardness is equal to or smaller than 3HSD, the depth of a surface quenching layer reaches 15mm-20mm, and the service life reaches over 20 years.