934 results about "Steel casting" patented technology

The invention relates to the technical field of sleeve grinding, and discloses cast steel sleeve precise grinding equipment which comprises a grinding wheel grinding mechanism, a chuck is installed below the grinding wheel grinding mechanism, a plurality of clamping jaws are installed in the chuck, and the tops of the clamping jaws do not exceed the upper surface of the chuck. An outer clamping jaw away from the circle center of the chuck and an inner supporting jaw close to the circle center of the chuck are installed on the surfaces of the clamping jaws correspondingly, a transmission range extending piece capable of enabling the outer clamping jaw and the inner supporting jaw to do range extending motion is installed on the surface of each clamping jaw, and rack limiting pieces used for limiting the outer clamping jaw and the inner supporting jaw to do one-way range extending motion are installed on the inner wall of the chuck. Through the design of the outer clamping jaw and the inner supporting jaw, compatibility of outer wall polishing and inner wall polishing in the same working procedure is achieved, compared with a traditional single inner supporting or outer clamping mode, the problem of polishing blind areas caused by clamp occupying is avoided, it is ensured that the inner wall and the outer wall of the cast steel sleeve can be completely machined at a time, two-time clamping is not needed, and the machining efficiency is improved. And the processing efficiency and the integrity are obviously improved.

The invention relates to the technical field of precision casting, and discloses a high-precision control method for stainless steel castings, which comprises the following steps: preparing raw materials, recording component characteristics of the raw materials, designing a formula proportion of the raw materials, carrying out pouring process design, and setting a parameter control system in each link of pouring, according to the shape of the needed stainless steel casting, mold design and manufacturing and mold quality control are carried out, grinding tool design parameters are recorded, a stainless steel casting solidification process simulation model is established according to raw material component characteristics, a raw material formula proportion, a designed pouring process and the mold design parameters, and the casting solidification process is simulated in the model. The method comprises the following steps: predicting a defect area in a casting production process, carrying out advanced prevention and optimization treatment on the defect area according to the predicted defect area in the casting production process, strengthening a refining degassing operation in a casting process, further carrying out a metal solution purification step after refining degassing, and demolding the casting, and the mold is cleaned, checked and maintained in time.

A seamless flux-cored wire for 10CrNiCu steel for ships, applied to welding of continuous casting 907A steel for a main hull and composed of a low-carbon steel sheath and a flux core. The diameter of the wire is 1.0-1.4 mm; the filling rate of flux-cored powder is 14%-16%; measured as the mass percentage of the flux-cored wire, the flux core contains rutile, aluminum oxide, ferroboron, zircon sand, quartz, bismuth oxide, potassium titanate, sodium fluoride, electrolytic manganese, ferrotitanium, magnesium powder, manganese-silicon alloy, nickel powder, metal chromium, copper powder, and iron powder. The seamless flux-cored wire for 10CrNiCu steel for ships has the advantages of good welding performance, stable mechanical properties, good crack resistance, low diffusion hydrogen content, high moisture absorption resistance, excellent rust resistance, and the like. Also provided is a method for manufacturing the seamless flux-cored wire for 10CrNiCu steel for ships

The invention relates to the technical field of manufacturing of engineering machinery parts, and discloses an engineering machinery driving wheel made of a medium carbon alloy cast steel material. The invention also discloses a preparation process of the engineering machinery driving wheel material, which comprises the following steps: S1, casting treatment: melting the medium carbon alloy steel material, and casting into a driving wheel blank; s2, normalizing heat treatment: carrying out normalizing heat treatment on the driving wheel blank; s3, rough machining treatment; s4, quenching treatment: carrying out induction quenching treatment; and S5, finish machining treatment. The synergistic effect of alloy elements in a medium carbon alloy cast steel material is combined with an optimized air cooling process, so that the cast steel is normalized to obtain a uniform structure which mainly contains superfine pearlite and contains extremely little ferrite, the matrix hardness is stable, and the requirement of a high-performance driving wheel is completely met; after the process route is improved, tempering and shot blasting and flaw detection procedures after tempering are canceled; the technological process is greatly shortened, material turnover is reduced, and the production efficiency is improved.

The invention discloses a polishing device and a polishing method for an inner curved surface of a steel casting, and relates to the technical field of cast steel production. The device comprises a main body frame and a polishing device, wherein the main body frame comprises a mounting table arranged on the main body frame; the stirring mechanism comprises a plurality of profiling plates which are mounted on the mounting table and used for stirring abrasive particle flow in the casting blank, and a plurality of rotating wheels are rotationally mounted on the inner wall of each profiling plate; the back pressure mechanism is used for driving the profiling plate to enter the casting blank; the rotating wheel is driven to rotate through resistance of abrasive particle flow, so that the abrasive particle flow completes switching between the distance from the abrasive particle flow to the central axis of the casting blank, and meanwhile, in the revolution process of the profiling plate, the abrasive particle flow in the casting blank is extruded up and down in a reciprocating mode through the action of a reciprocating mechanism; and the abrasive particle flow circularly polishes the inner wall of the casting blank up and down, so that the purposes of fully switching and contacting the abrasive particle flow and the inner wall of the casting blank, ensuring the polishing quality and improving the polishing efficiency are achieved.

The steering cast steel joint comprises a connecting bent pipe, a clamping structure and a bearing platform structure, an inserting channel used for installing a steel strand is formed in the connecting bent pipe, and the inner diameter of the inserting channel is larger than the outer diameter of the steel strand; the clamping structure is mounted on the steel strand; and the clamping structure is suitable for being clamped on the bearing platform structure to limit the steel strand, so that a mounting gap is formed between the steel strand and the inner wall of the insertion channel. The structure ensures that a mounting gap is formed between the steel strand and the inner wall of the insertion channel, the situation that friction is generated between the steel strand and the inner wall of the insertion channel, and consequently a coating on the surface of the steel strand is abraded is avoided, and the durability of the steel strand is improved.

The invention relates to the technical field of steel casting cutting, in particular to high-speed cutting equipment for machining steel castings, which comprises a rectangular cross beam frame, mounting seats are fixedly mounted at two ends of the cross beam frame, and an adjusting component is fixedly mounted on the front end face of the cross beam frame and can reciprocate along the length direction of the cross beam frame. The cutting assembly is fixedly installed on the front end face of the adjusting assembly, the adjusting assembly can drive the cutting assembly to conduct angle adjustment, and the cutting assembly conducts cutting machining on the steel casting through high-speed rotation. The cutting tool bit and the fixing piece can be independently replaced, the single-point maintenance cost is reduced, the limitation that a traditional tool needs to be integrally replaced when damaged is avoided, an annular cavity and a flow guide channel in the cutting rotary disc and spray holes and ventilation through holes in the fixing piece dissipate heat cooperatively, the temperature of a cutting area can be remarkably reduced, and the cutting efficiency is improved. The phenomenon of heat accumulation is avoided, the wear rate of the cutter is reduced, and the service life of the cutter is prolonged.

The present invention discloses a production method for reducing slag grooves during the casting process of spring steel billets, specifically: the superheat degree of the continuous casting molten steel is between 20 and 40°C, slag is automatically added to the continuous casting billet, and the protective slag is transported to the crystallizer through compressed air as a carrier, thereby ensuring a relatively high concentration of compressed air atmosphere at the upper mouth of the crystallizer, which has a combustion-supporting effect on the protective slag, thereby improving the melting effect of the protective slag. The insertion depth of the submerged nozzle is 70‑80mm, which ensures a relatively high temperature of the molten steel on the meniscus of the crystallizer, thereby improving the melting effect of the slag surface. The slag line remains unchanged during the casting process; the crystallizer uses high-frequency and high-amplitude vibration parameters to increase the negative slip time and the crystallizer vibration advance, which is beneficial to the inflow of liquid protective slag into the air gap between the billet and the copper tube, thereby avoiding the slag groove phenomenon during the billet casting process.

The present invention discloses a fine-grained, high-hardness and toughness martensitic wear-resistant cast steel and its preparation method and application, belonging to the technical field of wear-resistant cast steel and its heat treatment. The chemical composition of the fine-grained, high-hardness and toughness martensitic wear-resistant cast steel is, by mass percentage, C: 0.45-0.65%, Si: 0.5-2.0%, Mn: 0.4-1.0%, Cr: 0.6-1.4%, Ni: 0.3-1.2%, Mo: 0.2-0.7%, Zr: 0.01-0.06%, P≤0.032%, S≤0.040%, the balance being Fe and unavoidable impurities, 5.5×10 ‑7 ≤[Zr][C]wt%≤35×10 ‑7 The present invention optimizes the alloy composition and heat treatment process and utilizes liquid precipitation Zr (C, N) to refine the grains. The high-hardness and toughness martensitic wear-resistant cast steel obtained is particularly suitable for the preparation of wear-resistant parts under medium and low stress impact abrasive wear conditions.

The invention provides a method for improving homogenization of a bearing steel casting blank, belongs to the technical field of steel smelting processes, and solves the technical problems that in the continuous casting process of bearing steel, large-size compounds are easily formed due to high carbon and high chromium content, and micro segregation regulation and control of the bearing steel are difficult to solve by traditional electromagnetic stirring and soft reduction process parameters. According to the method for improving the homogenization of the bearing steel casting blank through soft reduction and tail end electromagnetic stirring coupling, a bearing steel continuous casting solidification mathematical model is established and corrected, and pouring condition technological parameters are input to provide basic data and boundary conditions for establishing the bearing steel continuous casting solidification heat transfer mathematical model; the method is applied to soft reduction process parameter design and is matched with adjustment of the tail end electromagnetic stirring position, the soft reduction technology and tail end electromagnetic stirring are coupled to be implemented, the solid fraction coupling rule between soft reduction and tail end electromagnetic stirring is determined, the homogeneity of a casting blank is jointly improved from the two dimensions of solidification structure and solute distribution, and center segregation is improved; and the structure uniformity is improved.

The invention provides low-temperature cast steel for polar ships and a heat treatment process of the low-temperature cast steel. The cast steel comprises the following chemical components in percentage by weight: 0.03-0.07% of C, 0.10-0.20% of Si, 1.3-1.5% of Mn, 3.0-4.0% of Ni, 0.80-1.00% of Al, 1.5-2.5% of Cu, not more than 0.05% of Cr and Mo, not more than 0.015% of S, not more than 0.020% of P and the balance of Fe and inevitable impurities. The cast steel has the advantages of ultra-large wall thickness, high strength, low-temperature high toughness, weldability, corrosion resistance and the like, and can meet the building requirements of polar region ship stem columns.

The invention belongs to the technical field of metallurgy, and provides a method for reducing erosion of a stopper rod in pure iron continuous casting production, which comprises the following steps of: blowing argon to seal a long nozzle bowl opening in a steel casting process, adding a covering agent to execute casting and adding twice in the process, and continuously injecting argon into a tundish impact area and a stopper rod area in the production process. A spinel stopper rod is adopted, and the outer diameter of the slag line part of the stopper rod is increased; by protecting the casting process design and optimizing the size and material of the stopper rod, the problem that the stopper rod is broken in the pure iron production process is solved, and stable and efficient continuous casting production of pure iron is achieved.

The present disclosure provides a high-vanadium high-speed steel and preparation method therefor, and use thereof, which relate to the technical field of high-vanadium high-speed steel. The preparation method includes: smelting raw materials to form a melt; impacting the melt to a cooling platform to form a high-vanadium high-speed steel casting billet; and performing a spheroidizing annealing treatment and a quenching and tempering treatment, so as to obtain a resultant. The spheroidizing annealing treatment includes: heating the high-vanadium high-speed steel casting billet to 820-910° C.; holding for 2-4 h; then cooling down to 450-550° C. at a cooling rate larger than 40° C. / h; and then air cooling to a room temperature.

The invention discloses a production method for improving cleanliness of a wear-resistant steel casting blank, and relates to the technical field of metal material smelting and continuous casting. The method comprises the following steps: optimizing electric arc furnace smelting, and reducing the oxygen content of molten steel by adopting a specific deoxidation system; a double-slag method is adopted in the LF refining stage, the size of inclusions is reduced through Ca treatment and rare earth denaturation, and the plasticity of the inclusions is improved; the vacuum degree and the degassing time are controlled in the RH degassing process, and the gas content in the molten steel is further reduced; and finally, an optimized protective casting process is adopted in the continuous casting process, a flow field is optimized in combination with electromagnetic stirring (EMS), and formation of secondary inclusions is reduced. By means of the method, the total amount of inclusions of the wear-resistant steel casting blank can be reduced by 30%-50%, the oxygen content is reduced to 0.0010% or below, the cleanliness of the casting blank is remarkably improved, and the comprehensive performance of the wear-resistant steel is improved. The method is stable in process and suitable for industrial production.

The invention discloses a low-cost method for purifying and modifying steel rail inclusions and improving comprehensive mechanical properties of the steel rail inclusions, and the method comprises the following steps: adding a rare earth iron alloy containing 30% of rare earth into molten steel in VD (vacuum degassing), and determining O in the steel before adding, the O is required to be less than or equal to 10ppm, so that the prepared molten steel for continuous casting comprises the following chemical components in percentage by mass: 0.78-0.85% of C; 0.50% to 0.60% of Si; 1.10% to 1.30% of Mn; less than or equal to 0.020% of P; s < = 0.008%; 0.20% to 0.30% of Cr, 0.003% to 0.008% of RE iron alloy or 0.0010% to 0.0024% of RE; and the balance of Fe and inevitable impurities. According to the method, A-D type inclusions in the steel can be obviously reduced, the purification effect and the modification effect of rare earth on the steel inclusions are fully achieved, and the service life of the steel rail is prolonged.

The invention provides valve steel casting strength detection equipment, and relates to the technical field of valve strength detection.The valve steel casting strength detection equipment comprises a transverse sliding rod, a U-shaped vertical supporting frame is welded to the top end of the transverse sliding rod, and a transverse force distribution plate is fixedly arranged below the transverse sliding rod; two L-shaped mounting plates are symmetrically and fixedly connected to the top ends of the square driving block and the vertical force transmission plate, U-shaped mounting frames are fixedly connected to the L-shaped mounting plates, and I-shaped driving parts are slidably mounted on the two U-shaped mounting frames; and two longitudinal limiting shafts are symmetrically and fixedly connected to the bottom end part of the transverse sliding rod, transverse sliding plates are slidably installed on the two longitudinal limiting shafts in a spring pushing mode, positioning insertion shafts are fixedly connected to the inner sides of the transverse sliding plates, and the I-shaped driving part is in penetrating sliding fit with the U-shaped transmission frame. According to the device, the switching and adjusting operation of the use states of the vertical supporting and jacking plate and the jacking swing plate can be driven and executed through one-time sliding of the vertical force transmission plate, the operation steps are simplified, and the operation and use efficiency of the detection equipment can be indirectly improved.

The invention relates to the technical field of slab continuous steel casting in the metallurgical industry, and discloses a method for rapidly replacing a high-carbon steel tundish in slab continuous casting. The method comprises the steps that when the tonnage of an old tundish is 45-50 t, the pulling speed is reduced to 0.8-0.9 m / min; when the tonnage of the old tundish is 22-25 t, the pulling speed is reduced to 0.35-0.45 m / min; when 16-18 t of old tundish molten steel is left, the pulling speed is reduced to 0.1-0.2 m / min; the casting speed is increased to 0.35-0.45 m / min when the liquid level of the crystallizer reaches a set value, and the casting speed is increased to 0.35-0.45 m / min when the casting speed is increased to 0.35-0.45 m / min when the casting speed is increased to 0.35-0.45 m / min; and when the new tundish molten steel reaches 45-50 t, the pulling speed is increased to 0.8-0.9 m / min. According to the method, the problem of tail blank chipping in the normal casting stopping process of the slab continuous casting high-carbon steel can be completely eradicated, and the problem that a joint blank is bumped or a casting blank cannot move in the slab continuous casting high-carbon steel tundish quick changing process is solved.

The invention discloses a welding repair method for cracks of a main frame of a 20Mn5 cast steel cone crusher, which comprises the following steps of: cleaning rust, dirt and oil dirt, punching a 65-80-degree double-groove and removing an oxide layer, using a high-strength and high-plasticity welding material and a direct-current welding machine, performing direct-current reverse connection, controlling the welding current to be 82.5-87.5 A and the electric arc length to be 1.2-1.8 mm, adopting a multi-layer welding mode, performing linear reciprocating operation on a first layer of welding bead, and performing welding on a second layer of welding bead and a third layer of welding bead, so as to repair the cracks of the main frame of the 20Mn5 cast steel cone crusher. And after the five layers of welding beads are welded, welding sine curves to strengthen the welding beads by taking a connecting line between the starting point and the ending point of the welding seam as a central line, preheating at 275-295 DEG C before welding, preserving heat at 210-230 DEG C for about 1.5 hours after welding, and carrying out shot peening hardening on ceramic shots of an ultrasonic flaw detector and the welding seam. According to the method, a high-strength and high-plasticity welding material and proper temperature control conditions are selected and used, welding cracks and welding deformation are effectively prevented, the tensile strength of a welding seam reaches 890 MPa and is higher than the tensile ultimate strength 785 MPa of 20Mn5, and welding repair of cracks of the main rack of the 20Mn5 cast steel cone crusher is met.

The invention relates to the technical field of continuous casting equipment in the metallurgical industry, in particular to a crystallizer assembly and a continuous casting machine, comprising a support table, the left side of the top of the support table is fixedly connected with a first support frame, the right side of the first support frame is provided with a crystallizer part, and the right side of the top of the support table is fixedly provided with a cooling part. According to the device, a second sliding block and a first sliding block are not supported by wind power and are influenced by gravity, the second sliding block and the first sliding block directly fall to drive a second toothed plate to descend, the second toothed plate drives a driven gear to rotate, and a first toothed plate drives a second supporting plate and a friction table to ascend; and when the cast steel continues to slide due to inertia, the cast steel stops sliding through friction between the high-friction coating on the top of the friction table and the cast steel, deformation of the cast steel is avoided, and therefore the situation that the overall structural strength of the solid casting blank is affected is avoided.

The invention discloses a steel casting grinding method and device based on 3D virtual-real combination man-machine cooperation. Firstly, casting three-dimensional point cloud is obtained, a polishing path is generated based on the casting three-dimensional point cloud, and then simulated polishing is conducted based on the polishing path. And the worker judges whether the polishing path is reasonable or not based on the casting three-dimensional point cloud and the target three-dimensional model, if not, the polishing path is corrected, and simulated polishing is repeated till the polishing path is reasonable. According to the method, the grinding path can be generated according to the three-dimensional point cloud of the steel casting, the grinding path can better fit the situation of the steel casting, and the machining requirements of castings of various models and sizes and different machining precision requirements can be met. And meanwhile, polishing simulation is further carried out, the reasonability of the polishing path is judged according to the effect of the target three-dimensional model, and the situation that the polishing robot carries out polishing based on the unreasonable polishing path is avoided. And compared with a fixed path grinding mode, the precision and the generation efficiency of steel casting grinding can be greatly improved.

The invention provides a preparation method of low-density steel, the low-density steel, a vehicle front anti-collision beam and a vehicle. The preparation method comprises the following steps: preparing low-density steel alloy components including Fe, Mn, Al, C, Nb and Ti; the smelted low-density steel alloy is subjected to double-roller thin-strip continuous casting, and a cast steel coil is obtained; and then homogenizing annealing, cold rolling, static recrystallization annealing and aging treatment are conducted, the low-density steel coil is obtained, the homogenizing annealing temperature ranges from 1000 DEG C to 1200 DEG C, the static recrystallization annealing temperature ranges from 900 DEG C to 1100 DEG C, and the aging treatment temperature ranges from 450 DEG C to 650 DEG C. As the binding force of Nb, Ti and C is very strong, amplitude modulation decomposition of austenite is inhibited, a more stable austenite matrix can be obtained, and meanwhile, through temperature control in all the steps, a kappa phase meeting the requirement is generated during aging treatment of the low-density steel, and a fine and dispersively distributed kappa phase is generated in crystal grains.

The invention discloses a preparation method of medium and low carbon chromium manganese martensite cast steel. The preparation method comprises the following steps: step 1, preparing raw materials; 2, high-temperature smelting; step 3, deoxidizing and desulfurizing; step 4, casting molding; step 5, annealing treatment; step 6, quenching treatment; step 7, tempering treatment; step 8, surface treatment; according to the invention, the medium-low carbon martensitic cast steel is designed, and the hardness and toughness of the martensitic cast steel are balanced by controlling the content of carbon in the cast steel, so that the problem of lower toughness of the martensitic cast steel under high carbon is avoided; meanwhile, the phenomenon that carbon elements are combined with chromium elements to be dispersed and separated out from grain boundaries or martensite laths in a carbide mode is reduced in cooperation with a heat treatment process, the corrosion resistance of the martensite cast steel is improved, meanwhile, the heat treatment process more suitable for medium and low carbon chromium manganese martensite cast steel is matched, various properties are further balanced, internal stress is eliminated, and the corrosion resistance of the martensite cast steel is improved. And the martensite structure is more uniform and stable.

The invention belongs to the technical field of metallurgy, and discloses an economical large-thickness steel plate and a manufacturing method thereof. The steel plate is formed by smelting the following components in percentage by mass: 0.10%-0.16% of C, 0.15%-0.45% of Si, 1.30%-1.60% of Mn, less than or equal to 0.012% of P, less than or equal to 0.001% of S and the like, and the balance of Fe and inevitable impurities. The manufacturing method comprises the steps of primary smelting, refining, continuous steel casting, heating and controlled rolling. According to the method, the high-compactness continuous casting slab refining and continuous casting technology is combined with the controlled rolling technology with microalloy carbonitride point enrichment nucleation as the core, a grain refined mixed structure is obtained, the problems that the compression ratio is low and grains are coarse when a large-thickness steel plate is produced through a continuous casting slab are solved, the thickness of the produced steel plate reaches 100-150 mm, and the yield of the steel plate is improved. The internal quality, strength and low-temperature toughness are excellent, and the continuous casting billet is produced by controlling rolling, so that the economical efficiency is good.

The invention relates to the technical field of large steel casting manufacturing, and discloses a crusher rack set for mining machinery and a casting method of the crusher rack set. The rack set comprises a cast steel body and a functional gradient reaction framework which is arranged in the cast steel body in advance and forms metallurgical bonding. The framework is made of refractory metal alloy, and an A area and a B area are divided on the framework. The area A is arranged at the heat accumulation core of the casting and is provided with a strong reaction coating on the surface; the area B extends outwards from the area A, and the surface of the area B is provided with a high-thermal-conductivity ceramic coating. The method comprises the steps of preparing the framework, installing the framework in a casting mold cavity, and then carrying out molten steel pouring and heat treatment. In-situ forced nucleation is initiated at the core of the casting through the strong reaction coating of the area A, a heat conduction path from inside to outside is established by means of the high heat conduction coating of the area B, and sequential solidification of the casting is achieved, so that defects such as shrinkage porosity and shrinkage cavities are effectively transferred, the density and uniformity of the internal structure of the casting are improved, and the casting quality is improved. And the overall mechanical property of the rack set is improved.

The present invention belongs to the field of metallurgical equipment technology, specifically relating to a continuous casting ladle drainage sand discharge device and its use method. The present invention utilizes an annular left-connected sand trough and an annular right-connected sand trough, forming a full-ring inner bore, as a channel for the molten steel to fall. A drainage cone is positioned at the upper end of the channel. As the drainage sand falls, the cone acts to cause it to fall into the interiors of the first and second sand holding chambers below, enabling recovery. When the molten steel contacts the drainage cone, the high temperature causes the cone to melt and flow along with the molten steel from the channel into the tundish below, preventing the molten steel from contacting the annular left and right sand troughs. After the drainage sand is recovered, a separation mechanism separates the annular left and right sand troughs to either side of the molten steel flow. This effectively prevents splashing caused by contact between the annular left and right sand troughs during movement, thereby extending the service life of the discharge device.

The invention discloses antioxidant heat-resistant cast steel and a preparation method thereof. The cast steel comprises the following components in percentage by mass: 0.08-0.15% of C; 0.1% to 0.8% of Zr; 0.05% to 0.8% of Hf; 0.1% to 0.8% of Re; 8.0% to 11.0% of Cr; 0.5% to 2.5% of Ni; 1.0% to 2.0% of Mo; 0 < Si < = 0.5%; 0 < Mn < = 1.0%; 0 < P < = 0.025%; 0 < S < = 0.015%. According to the antioxidant heat-resistant cast steel added with zirconium, hafnium and rhenium and the electroslag remelting preparation method of the antioxidant heat-resistant cast steel, the grain size of heat-resistant steel is larger than or equal to the ASTM7 grade; the service life is not less than 500 hours under the conditions of 650 DEG C and 170 MPa, the service life is not less than 150 hours under the conditions of 700 DEG C and 100 MPa, and the weight gain rate is not more than 0.1 mg / cm < 2 > after oxidation for 100 hours at 700 DEG C.

The invention belongs to the technical field of wear-resistant cast steel, and discloses high-hardness and high-toughness wear-resistant cast steel as well as a preparation method and application thereof. The high-hardness and high-toughness wear-corrosion-resistant cast steel is prepared from the following chemical components in percentage by mass: 0.20 to 0.45 percent of C, 1.0 to 2.3 percent of Si, 0.4 to 0.9 percent of Mn, 0.6 to 1.4 percent of Cr, 0.8 to 1.8 percent of Ni, 0.2 to 0.6 percent of Mo, 0.5 to 1.5 percent of Cu, 0.03 to 0.08 percent of RE, less than or equal to 0.032 percent of P, less than or equal to 0.040 percent of S and the balance of Fe and inevitable impurities. Si / C > = 4.2, and 1.4% < = (Ni + Cu) < = 2.8%. By optimizing alloy components and a heat treatment process, the prepared cast steel has high hardness, excellent toughness and corrosion resistance, and the high-hardness and high-toughness wear-resistant steel is simple in preparation process, low in cost and good in application prospect.

The utility model relates to an assembly type transition section structure and a framework type wind power tower. The transition section structure comprises four split structures of the same structure, and the four split structures are mutually assembled; each split structure comprises a cast steel pipe, a transition section side plate, a transition section cone plate and a flat plate connecting part; the bottom end of the transition section cone plate is connected with the cast steel pipe, and the top end of the transition section cone plate is fixedly provided with a segmented flange; the transition section side plates are arranged on the two sides of the cast steel pipe, and the top ends of the transition section side plates are connected with the transition section conical plate. Each flat plate connecting part is arranged at the splicing position of the transition section cone plate and the transition section side plate in every two adjacent split structures and connected and fixed through bolts. And a cast steel flange is arranged at the bottom end of the cast steel pipe. Compared with an integral transition section, the assembly type transition section structure is convenient to transport, bolts are used for assembly and connection on site, the construction speed is high, the assembly efficiency is high, and the quality is easy to guarantee.

The invention relates to the field of steel casting grinding, and discloses a steam turbine heat-resistant steel casting grinding device and a process thereof.The device comprises an electric grinding machine, the electric grinding machine is arranged on the head of an automatic telescopic arm, the tail of the automatic telescopic arm is rotationally connected with a fixed disc, and a rotary disc is in transmission connection with a servo motor; the servo motor and the fixing disc are fixedly arranged on the supporting frame, the supporting frame is installed on an installation plate of the electric sliding rail, the electric sliding rail penetrates through an inner cavity of a valve shell to be polished, and the two ends of the electric sliding rail are fixed to the machining table through supports. An inner supporting structure is arranged on the supporting frame and provides radial supporting. A camera is further fixedly arranged on the cylinder body of the automatic telescopic arm through a supporting rod, and a cleaning keeping mechanism is arranged on the camera. According to the technical scheme, the inner cavity of the valve shell is effectively polished, the polishing condition is monitored in real time through the camera, and the camera is always in a clean state through the arranged cleaning keeping mechanism.

The application provides a structure Cu-containing Mo-V micro-alloy cast steel and a preparation method thereof. The cast steel material is composed of the following components in percentage of mass fraction: C: 0.06-0.13%, Mn: 1.3-1.9%, Si: 0.2-0.4%, Ni: 0.5-1%, Mo: 0.18-0.42%, V: 0.05-0.09%, and Cu: 0.25-0.65%. The method comprises the following steps: step one, adding a blank into an electric arc furnace or an induction furnace; step two, performing conventional smelting on the blank to obtain a molten steel with a required mass target component; step three, adjusting the temperature of a semi-finished cast steel and tapping the molten steel to obtain the cast steel; step four, performing heat treatment on the cast steel; and step five, judging the qualification of the cast steel to obtain a high-quality finished cast steel. Through the structure Cu-containing Mo-V micro-alloy cast steel and the preparation method thereof, the yield strength grade of the non-quenching + tempering type micro-alloyed precipitation strengthening type cast steel can be further improved, the low-temperature toughness of a large-size structure cast piece under a conventional process can be improved, and the cost consumption of the large-size structure cast piece under the conventional process can be reduced.