146 results about "Carbon alloy" patented technology

The invention provides a high-homogenization medium-low carbon alloy steel large-section rectangular blank and a preparation method, and belongs to the field of special steel continuous casting. The medium-low carbon alloy steel comprises, by mass, 0.2%-0.45% of C, 0.5%-1.1% of Cr and Mn in alloy, 0.01%-0.1% of Ti in alloy, and the section of the medium-low carbon alloy steel is 320-390 mm * 385-510 mm. The electromagnetic stirring mode that the stirring frequency determined by the maximum electromagnetic stirring force is matched with weak crystallizer electromagnetic stirring and strong solidification tail end electromagnetic stirring is adopted, the strong secondary cooling specific water flow is combined, and the position of a solidification tail end electromagnetic stirrer is the position where the center solid fraction is 0.1-0.2. The press-down position is 0.25-0.85, the press-down amount is 5-12 mm, the press-down position is 0.9-1, and the press-down amount is 5-6 mm. According to the method, the component uniformity of the section of the casting blank can be remarkably improved, and macroscopic frame segregation is improved.

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 relates to a 1250MPa-grade high-strength tool steel wire rod and a manufacturing method thereof.The manufacturing method includes the steps that after medium-carbon alloy components containing trace Nb and V are designed, rolled and spun into a wire rod, online molten salt quenching strong isothermal treatment is conducted, the wire rod is made to pass through front-section molten salt firstly, the wire rod is controlled to enter a bainite phase region from a high-temperature austenite state at the cooling speed larger than or equal to 35 DEG C / s, and then the high-strength tool steel wire rod is manufactured; the preparation method comprises the following steps: firstly, quenching bainite is taken as a main raw material to form a quenching structure taking the quenched bainite as a main raw material, then, the steel wire rod with a microscopic structure comprising tempered bainite and ferrite is prepared through rear-section molten salt heating, isothermal tempering and toughening destressing treatment on the quenching structure, carbide precipitation control and roller way slow cooling finally, and the strength and plasticity matching of the steel wire rod can be improved by adjusting the structure state, so that the strength and plasticity of the steel wire rod are improved. The tensile strength is 1175-1225 MPa, the percentage reduction of area is 58%-63%, and the steel can be directly machined into parts after cold machining forming, so that the production energy consumption of the tool steel is reduced, the cost is reduced, and the efficiency is improved.

The invention relates to the technical field of steelmaking, in particular to a method for controlling hydrogen content in a low alloy steel smelting process, which comprises the following steps: pre-desulfurizing molten iron until S is less than or equal to 0.01%; the converter tapping temperature is not lower than 1670 DEG C, high-carbon alloy is adopted for converter tapping to increase the carbon content, and a carburant is not added; before LF refining production, it is checked that an LF cover does not leak water, dry lime is contained in the LF, molten steel enters the LF and then is premixed, the LF is heated once, the heating time is shorter than 20 min, 2-7 kg / t of dry lime and 0.4-1.5 kg / t of slag melting agent are added in the heating process, and the temperature of the molten steel is increased to 10-15 DEG C higher than the carrying-out temperature; a carburant is added, the alloy is strongly stirred for 2-5 min, the adding amount of the carburant is smaller than or equal to 0.6 kg / t, the argon flow is larger than 60 m < 3 > / h during strong stirring, weak argon blowing is conducted for 5-10 min, and the argon flow is smaller than 30 m < 3 > / h during weak argon blowing. LF refining is adopted, the hydrogen content of the low-alloy steel is controlled without vacuum degassing treatment, and the steelmaking cost of the low-alloy steel is reduced.

The invention relates to medium-carbon alloy steel for a large industrial bearing and a production method of the medium-carbon alloy steel, and belongs to the field of iron-based alloy. The round steel comprises the following chemical components: 0.44 to 0.50 percent of C, 0.15 to 0.35 percent of Si, 0.60 to 0.90 percent of Mn, 1.0 to 1.30 percent of Cr, 0.5 to 0.9 percent of Ni, 0.25 to 0.40 percent of Mo, 0.05 to 0.10 percent of V, less than or equal to 0.20 percent of Cu, less than or equal to 0.05 percent of Al, less than or equal to 0.0008 percent of Ca, less than or equal to 0.008 percent of S, less than or equal to 0.015 percent of P, less than or equal to 0.0020 percent of Ti, less than or equal to 0.0012 percent of O, less than or equal to 0.03 percent of As, less than or equal to 0.03 percent of Sn, less than or equal to 0.005 percent of Sb, less than or equal to 0.002 percent of Pb and the balance of Fe and inevitable impurities. The production process comprises the steps of molten iron pretreatment, converter smelting, LF refining, RH refining, CCM continuous casting round billet, annealing and finishing. Forging with the compression ratio of 6 or above is adopted, and the grain size is larger than or equal to 6 grades. And on the basis of meeting the quality requirement of the steel for the medium-carbon bearing, the production cost is lower, and the steel has very strong market competitiveness.

The invention relates to the technical field of petroleum engineering, in particular to a concentric soft and hard combined coiled tubing acidification and chemical sand prevention device and a using method. According to the technical scheme, the upper portion of an overflowing connector is connected with a concentric soft and hard combined continuous oil pipe composed of a continuous low-carbon alloy steel pipe and a continuous rubber pipe, and the top of the concentric soft and hard combined continuous oil pipe is connected with a ground pressing connector; the outer side of the upper end of the well washing connector is connected with a continuous low-carbon alloy steel pipe, and the inner side of the upper end of the well washing connector is connected with a continuous rubber pipe. When an acidifying agent or a chemical sand consolidation agent is injected through the continuous rubber pipe, the continuous rubber pipe is pressed to deform towards the outer side and lean against the inner wall of the continuous low-carbon alloy steel pipe, so that the liquid passing capacity is improved, and the through-flow capacity of the throttler and the capacity of injecting the acidifying agent or the chemical sand consolidation agent into the stratum are also improved; in addition, when the well washing fluid is injected through the annulus, the function of rapid well washing is achieved, and the problem that in the well washing process, the well washing fluid enters the stratum, and consequently a well washing channel cannot be achieved is solved.

The invention discloses modified high-carbon alloy steel and a preparation method and application thereof, and belongs to the technical field of high-carbon alloy steel for aluminum alloy forming dies. The preparation method disclosed by the invention comprises the following steps: carrying out electroslag remelting on a high-carbon alloy steel rod to obtain a casting blank; carrying out thermoplastic deformation on the casting blank to obtain a blank; the blank is annealed, so that carbides in the blank are eliminated or become fine particles, spherical graphite can be separated out, and the modified high-carbon alloy steel is obtained; the particle size of the fine particles is smaller than 10 microns. According to the method, coarse and large carbides which are difficult to eliminate in the high-carbon aluminum alloy forming die steel containing strong carbide forming elements such as Cr, Mo and V or medium-strong carbide forming elements are subjected to rapid and basic graphitization through a thermoplastic deformation and high-temperature graphitization combined process; the technical problem that carbide decomposition and graphite precipitation control are difficult to realize in the existing method is solved.

This invention discloses a dual-frequency composite induction strengthening process for medium carbon steel, gradient hardened layer parts, and a production system. The process includes: selecting SAE 1045 medium carbon steel and performing quenching and tempering pretreatment; precision machining to form outer circular channels and inner ball channels; performing dual-frequency composite induction hardening on the outer circular channels and inner ball channels respectively, i.e., preheating to 680-750℃ with medium-frequency current, then rapidly heating to 880-920℃ with high-frequency current followed by spray cooling, and using thermal balance control to form a gentle transition zone with a width of 2-5mm between the two hardened zones, where the hardness gradient along the axial line connecting the two hardened zones does not exceed ΔHRC10 / mm; finally, low-temperature tempering. This invention also discloses wear-resistant parts with a dual-layer composite hardened layer structure and a gradient transition zone prepared using this process, as well as an online composite strengthening production system. This invention replaces low-carbon alloy steel with medium-carbon steel and replaces overall carburizing with local dual-frequency induction hardening, which can reduce raw material costs and energy consumption, reduce deformation, and obtain a hardened layer that meets the depth requirements, thus realizing online continuous production of heat treatment and machining.

The application discloses a composite modification process of a high-toughness wear-resistant cutter ring for a shield tunneling machine, and comprises the following steps: step one, a medium-carbon alloy steel material is used as a cutter ring base body, and a blank is prepared by using a hot forging process; step two, the blank obtained in the step one is subjected to carburizing quenching treatment, and then is subjected to oil cooling; step three, the cutter ring after the oil cooling in the step two is subjected to high-temperature tempering treatment, so that unstable martensite after quenching is completely converted into tempered martensite; step four, the cutter ring after the high-temperature tempering in the step three is subjected to surface induction quenching; step five, the cutter ring after the induction quenching in the step four is subjected to low-temperature tempering treatment; and step six, the cutter ring after the low-temperature tempering in the step five is subjected to surface layer ultrasonic impact modification, so as to obtain a composite modified cutter ring. The application uses heat treatment processes such as carburizing and nitriding and ultrasonic impact modification, and constructs a gradient structure cutter ring, so that the cutter ring has high wear resistance, buffer resistance and impact toughness.

The mill lining plate comprises a lining plate body, the lining plate body is of an arc-shaped structure, a first side wall and a second side wall are arranged at the two ends of the lining plate body in the circumferential direction, at least two screw holes are formed in the first side wall, bolts are arranged in the screw holes, a T-shaped sliding groove is formed in the second side wall, and the T-shaped sliding groove is communicated with the first side wall and the second side wall. The screw head of the bolt is matched with the T-shaped sliding groove in shape. The bolts and the T-shaped sliding grooves are formed in the two sides of the lining plates correspondingly, the screwing-in depth of the bolts on one lining plate is adjusted before installation, then the bolts are inserted into the T-shaped sliding grooves of the adjacent lining plates to form limiting, and in the process, the reserved gap between the two lining plates is accurately adjusted through the screwing-in depth of the bolts; therefore, a deformation gap is provided for thermal expansion in the working process of the mill, and the lining plate can be prevented from being deformed and damaged due to thermal expansion.

The present invention provides a highly homogenized medium- and low-carbon alloy steel large-section rectangular billet and preparation method, belonging to the field of special steel continuous casting. The medium- and low-carbon alloy steel has a carbon content of 0.2-0.45% by mass, alloy Cr and Mn contents of 0.5-1.1% by mass, and a Ti content of 0.01-0.1% by mass, with a cross-section of 320-390 mm x 385-510 mm. The steel adopts an electromagnetic stirring mode that matches weak crystallizer electromagnetic stirring with strong solidification end electromagnetic stirring at a stirring frequency determined by the maximum electromagnetic stirring force, combined with a relatively strong secondary cooling water ratio, and a position of the electromagnetic stirrer at the end of solidification at a center solid phase ratio of 0.1-0.2, a light reduction of 0.25-0.85 and a reduction of 5-12 mm, and a heavy reduction of 0.9-1© and a reduction of 5-6 mm. The present invention can significantly improve the compositional uniformity of the ingot cross section and improve low-magnification frame segregation.

The invention belongs to the technical field of gear production, and discloses a strengthened wear-resistant gear and production equipment thereof.The strengthened wear-resistant gear comprises a gear base body, a gear surface strengthening layer and a transition layer, the gear base body is made of medium-carbon alloy steel, and the surface strengthening layer is formed by high-hardness alloy powder through a thermal spraying process; the transition layer is located between the gear base body and the surface strengthening layer and used for improving the bonding strength between the gear base body and the surface strengthening layer, the gear base body comprises a tooth part, a hub and a key groove, the end face of the tooth part is fixedly connected with the hub, and the key groove is located in the center of the hub. It is ensured that the expansion block can effectively adapt to the combination of gears of different sizes, the movable ring and the connecting rod system, the expansion range of the expansion block can be flexibly adjusted according to needs, and therefore the machining requirements of the gears of different specifications are met.

This invention relates to a method and product for efficiently solidifying coarse primary carbides in high-carbon alloy steel, belonging to the field of high-carbon alloy steel production. The method includes the following steps: determining the thermodynamic equilibrium temperature A3 corresponding to the nominal composition of the high-carbon alloy steel billet or ingot for complete austenite transformation; calculating the degree of segregation of solute elements and the corresponding solidus temperature T based on the steel composition of the high-carbon alloy steel billet or ingot and the cooling rate under actual solidification conditions. SS During the cooling and solidification process or the heating and solution treatment process of high-carbon alloy steel billets or ingots, A3~T SS Electrical pulse treatment is performed within a temperature range of -200℃, followed by a period of treatment and air cooling to room temperature. The resulting billet or ingot is then heated to 900–1150℃ and held for 1–3 hours, followed by hot deformation and air cooling to room temperature. This invention achieves efficient solution treatment (annealing time ≤3 hours) of primary carbides in high-carbon alloy steel at relatively low temperatures (≤1150℃) through electrical pulse treatment during the cooling process of hot billets / ingots or the solution treatment process of cold billets / ingots.

The application discloses a kind of wind power main shaft and the manufacturing method for improving its fatigue resistance, belong to wind power equipment key component manufacturing technical field.The method includes the following steps: multi-direction upsetting and drawing forging is carried out to medium carbon alloy steel ingot, and blank is obtained;The blank is cryogenically pretreated, and then heated to room temperature;Then, composite quenching and tempering heat treatment, surface composite strengthening treatment and low-temperature aging treatment are carried out in sequence.The above-mentioned method is easy to operate, can effectively improve the fatigue life of wind power main shaft, compared with the fatigue life of wind power main shaft manufactured by traditional process can be improved by 50%-100%, and the damage tolerance and safety reliability of wind power main shaft under severe working conditions can also be greatly improved.

The utility model relates to deep hole drilling equipment based on a lathe, which relates to the field of deep hole drilling and comprises the lathe and a deep hole drilling mechanism, the lathe is provided with a lathe frame, a three-jaw chuck and a feed frame, the three-jaw chuck is rotatably connected with the lathe frame, and the feed frame is slidably connected with the lathe frame. The deep hole drilling mechanism comprises two deep hole drill bits, a gas pulse assembly and a liquid pulse assembly, one deep hole drill bit is detachably connected with the feeding frame, gas-liquid through holes are formed in the deep hole drill bits, and the gas-liquid through holes of the two deep hole drill bits are communicated with the gas pulse assembly and the liquid pulse assembly respectively. The device has the beneficial effects that the idle lathe is transformed and upgraded, so that the production pressure of deep hole machining of parts is relieved, and on-time delivery of deep hole drilling products of part machining lines during peak seasons is ensured. The method is especially suitable for batch processing of non-ferrous metal and other materials and small-batch production of medium-carbon alloy steel.

The present invention discloses a low-cost method for preparing tantalum-tungsten alloy powder, comprising the following steps: degassing: uniformly mixing ultrafine tantalum powder and tungsten powder in a desired proportion to obtain a mixed powder, placing the obtained mixed powder into a degassing device, evacuating and heating the mixture to volatilize and discharge gas impurities in the mixed powder; isostatic pressing: placing the degassed powder into a rubber mold sleeve, isostatically pressing the powder under a high-pressure environment to densify the powder, and placing the obtained molded body into a vacuum sintering furnace for sintering. The present invention can provide an effective way to manufacture low-cost, low-oxygen, low-carbon alloy powder for refractory metal spherical powder used in additive manufacturing. It can recycle and reuse low-grade, high-oxygen, unqualified tantalum-tungsten alloy fine powder waste to produce tantalum-tungsten alloy spherical powder that meets or exceeds industry standards, significantly reducing the production cost of powder preparation, saving time and effort, and improving work efficiency.

The invention provides a three-dimensional nano iron-carbon foam alloy material as well as a preparation method and application thereof. According to the three-dimensional nano iron-carbon foam alloy material, iron and carbon elements form a continuous three-dimensional nano porous network structure; in the three-dimensional nano porous network structure, the carbon element serves as a structure stabilizer and forms an integrated alloy system with the iron element. The technical problem to be solved is how to obtain a three-dimensionally communicated nano-porous iron-carbon alloy system with stable structure and uniform pore diameter, solves the technical problems that an iron-based nano-porous material is easy to coarsen, the structure is easy to collapse and an iron component is easy to agglomerate and fall off, and provides a preparation scheme which is controllable in process, low in cost and suitable for large-scale production. And the specific surface area, the number of surface active sites, the mass transfer efficiency, the conductivity and the cycle service life of the material are synchronously improved, so that the high-performance application requirements in high-tech fields such as catalysis and electrochemical energy storage are met, and the material is more practical.

The invention provides a composite inorganic salt water-based quenching medium and a heat treatment method of a steering knuckle, and belongs to the technical field of heat treatment, the composite inorganic salt water-based quenching medium comprises the following components by weight: 1%-3% of sodium chloride, 10%-14% of pyrophosphate, 4%-6% of potassium sulfate, 3%-5% of hexametaphosphate, 3%-9% of an antirust preservative and the balance of water. According to the composite inorganic salt water-based quenching medium disclosed by the invention, in the heat treatment of the automobile steering knuckle, the three-stage cooling process is optimized through the synergistic effect of all inorganic salt components, so that the hardness and metallographic structure uniformity of the quenched steering knuckle are remarkably improved, and the rejection rate of the steering knuckle is remarkably reduced; the use temperature of the composite inorganic salt water-based quenching medium is wider than the applicable temperature range of the traditional PAG medium; and the medium-carbon alloy steel steering knuckle is quenched at the temperature of about 800 DEG C, the quenching temperature is reduced by 40-60 DEG C compared with the prior art, and the energy saving performance is improved.

The present invention provides a high-carbon alloy steel large-section rectangular billet and preparation method based on multi-field synergy, belonging to the field of special steel continuous casting. The high-carbon alloy steel has a C content of 0.6-1.0% by mass, and the Cr and Mn content of the alloy is 0.5-1.1% by mass. The cross-section is 320-390 mm × 385-510 mm. A Gauss meter based on a low-frequency alternating mode is used to measure the magnetic induction intensity at the center of the crystallizer and the electromagnetic stirrer at the end of solidification. The stirring frequency is determined based on the relationship between the measured magnetic induction intensity and the electromagnetic torque. The electromagnetic stirrer at the end of solidification is positioned at a central solid phase ratio of 0.1-0.2, with a light reduction at a reduction position of 0.3-0.8 and a reduction of 12-20 mm, and a heavy reduction at a reduction position of 0.9-1 and above and a reduction of 10-12 mm. The present invention controls the composition uniformity and central density of the ingot through the synergistic effect of the electromagnetic field and the mechanical stress field.

The invention relates to a method for accurately regulating and controlling ultralow carbon content of IF steel, which comprises the following steps: carrying out primary slag modification on original molten steel to obtain low-carbon oxygen-containing molten steel; the low-carbon oxygen-containing molten steel is subjected to vacuum decarburization, and decarburized molten steel is obtained; a deoxidizing agent and a carbon-containing alloy are added into the decarburized molten steel, and ultra-low carbon molten steel is obtained; the ultra-low carbon steel liquid is sequentially subjected to secondary slag modification and blank casting, and an IF steel blank is obtained; the termination signal of the vacuum decarburization comprises at least one of the following signals: a, when the decarburization time of the vacuum decarburization is greater than or equal to 8 minutes, the oxygen content of the molten steel is continuously measured twice every 2-3 minutes in the vacuum decarburization process, and the oxygen content deviation absolute value of the two measured values of the vacuum decarburization is less than or equal to 10 ppm; and b, the decarburization time of the vacuum decarburization is more than or equal to 12 minutes. Differentiation regulation and control are implemented based on steel grade requirements after vacuum decarburization, residual carbon is reduced while the carbon content of the IF steel is stably controlled, conditions are created for adopting low-cost alloy, and the problem of carbon content fluctuation in a traditional process is solved.

The present invention provides a method for preparing a carbon-nitride-assisted laser-strengthened wear-resistant layer, comprising: Step A, first, dividing the surface of the alloy to be treated into a structure with a base region and a strengthening region spaced apart from each other, and coating the surface of each strengthening region with a carbon layer structure; Step B, placing the alloy sample in a sealed glass container, and sequentially introducing nitrogen gas and liquid nitrogen; Step C, using a laser head to laser-melt the strengthening regions; and Step D, repeating Step C to complete the carbonitriding laser strengthening of all strengthening regions. This method targets the surface of alloy steel with low carbon content through laser melting and strengthening, utilizing the principles of carbonitriding to modify and strengthen the low-carbon alloy surface, resulting in the alloy surface exhibiting excellent wear resistance and fatigue resistance.

This invention discloses a heavy-duty gearbox shell based on gradient-optimized composite materials and its manufacturing process, relating to the fields of material design and equipment manufacturing technology. The shell body is an integrally formed gradient heterogeneous composite structure with the following gradient design: a core load-bearing layer located in the gear meshing area, bearing housing, and flange connection surface of the shell body, made of a composite powder of high-carbon chromium-molybdenum steel powder and nano-ceramic particles; a transition buffer layer connecting the core load-bearing layer and the lightweight support layer, made of a composite powder of medium-carbon alloy steel powder and short carbon fibers; and a lightweight support layer located on the sidewalls and non-stressed areas of the shell body, made of a composite powder of aluminum alloy powder and hollow ceramic microspheres. The thickness ratio of the core load-bearing layer, transition buffer layer, and lightweight support layer in the radial section is 1:1.4:1.6. This invention, based on a three-dimensional gradient heterogeneous composite structure, achieves precise matching of material properties and load distribution, optimizing and improving load-bearing capacity while maximizing lightweight design.

The invention relates to the technical field of household appliances, and discloses a welding method which comprises the steps that powder spraying melting treatment is carried out on the to-be-welded face of a first welding piece, so that an alloy welding layer is formed on the surface of the first welding piece, and the thickness of the alloy welding layer is larger than or equal to 0.5 mm; the alloy powder subjected to powder spraying melting treatment comprises at least one of low-carbon alloy steel, nickel-cobalt alloy steel and iron-based superalloy; and the alloy welding layer and the to-be-welded face of a second welding piece are oppositely arranged, laser penetration welding treatment is conducted on the alloy welding layer and the to-be-welded face of the second welding piece, and welding connection is formed between the first welding piece and the second welding piece. And forming of high-strength welding connection is facilitated.

The invention belongs to the technical field of metal ceramic composite materials, and particularly relates to a high-performance metal ceramic composite grinding roller and a preparation method thereof. The grinding roller sequentially comprises a grinding surface layer, a pure metal transition layer and a tough roller core from outside to inside, the grinding surface layer, the pure metal transition layer and the tough roller core are metallurgically bonded into a whole, the grinding surface layer is formed by compositing a multi-system ceramic reinforced phase and a high-toughness high-chromium cast iron matrix, ceramic particles are subjected to NiP amorphous coating treatment, and through three-level particle size matching and PSZ secondary reinforced phase optimization distribution, the high-toughness high-chromium cast iron matrix is obtained. The roller core is made of medium-carbon alloy steel; the preparation method comprises the five steps of ceramic prefabricated body preparation, roller core pretreatment and assembly, centrifugal casting compounding, vacuum sintering densification and differential temperature heat treatment and finish machining. Through coupling of multiple technologies, the technical bottlenecks of weak bonding of ceramic and metal interfaces and uneven particle distribution are fundamentally solved, the prepared grinding roller has ultrahigh wear resistance and excellent impact resistance (transition area impact toughness AKU gt, 30 J), the structure is uniform, compact and flawless, and the service life of the grinding roller is more than three times that of a traditional high-chromium cast iron grinding roller.

The present application relates to the technical field of petroleum engineering, and particularly relates to a concentric soft and hard combined coiled tubing acidification and chemical sand control device and a use method thereof. The technical scheme is as follows: the upper part of a flow connection head is connected with a concentric soft and hard combined coiled tubing composed of a continuous low-carbon alloy steel pipe and a continuous rubber pipe, and a ground pressing connector is connected to the top of the concentric soft and hard combined coiled tubing; the lower end of a well flushing connector is connected with a lower connector through a connecting pressure cap, the upper end of the well flushing connector is connected with the continuous low-carbon alloy steel pipe on the outside and connected with the continuous rubber pipe on the inside. When the acidification agent or the chemical sand consolidation agent is injected through the continuous rubber pipe, the continuous rubber pipe is deformed outwardly under pressure and leans against the inner wall of the continuous low-carbon alloy steel pipe, so that the liquid passing capacity is improved, and the flow capacity of the flow restrictor and the injection capacity to the formation are also improved; in addition, when the well flushing fluid is injected through the annulus, the function of rapid well flushing is realized, and the problem that the well flushing channel cannot be realized due to the well flushing fluid entering the formation during the well flushing process is avoided.

The application discloses a laser welding method of hard alloy and high-carbon alloy steel, which comprises the following steps: cleaning the welding position of the base material; filling the intermediate solder between the welding surfaces of the base material; pressing the base material in the direction of the close welding surfaces; welding the base material by using the laser beam under the protection of argon; coating the anti-oxidation paint on the surface of the welding joint of the base material and drying; heating the welded material to 750-850 DEG C, keeping warm for 1-2 hours; heating to 150-250 DEG C after oil quenching treatment, tempering for 2-3 hours, and then taking out the furnace and air cooling to room temperature; the anti-oxidation paint is mixed by the powder and the binder according to the mass ratio of 1:0.3-1, the powder comprises the following components according to the mass ratio: graphite powder 20-40%, alumina powder 30-50% and silica powder 30-50%, and the binder is water glass. The welding method solves the decarburization problem during the welding of the high-carbon alloy steel and improves the welding quality of the high-carbon alloy steel and the hard alloy.

A kind of wear-resistant bucket tooth containing titanium for stripping wheel excavator and its manufacturing method belong to the technical field of bucket tooth manufacturing of wheel excavator.The wear-resistant bucket tooth for stripping wheel excavator includes titanium-containing low-carbon alloy steel base body and tungsten carbide (WC) overlaying layer.In the production process, water cooling + oil cooling is used for quenching, which can effectively reduce the cracking of the bucket tooth base body during quenching, and then low-temperature tempering is carried out to eliminate internal stress while ensuring high hardness of the bucket tooth;The production process has good continuity, and can avoid the hardness reduction and cost increase caused by secondary heating during overlaying.The overlaying layer and the base body of the present application are firmly combined, and have strong anti-peeling property.The bucket tooth made of the material after the above production process has excellent wear resistance and long service life under stripping working conditions of wheel excavator.

The invention discloses a method for improving cracks of a 9SiCr casting blank, which comprises the following steps of: feeding a pure calcium line into molten steel to carry out calcium treatment on the molten steel, controlling the pure calcium line fed into the first furnace of molten steel to be 1.2-1.4 m / t, and controlling the pure calcium line fed into the second furnace of molten steel to be 0.7-0.9 m / t; the total aluminum content Alt in the steel is controlled to range from 0.020% to 0.035%; controlling the superheat degree of the molten steel to be 20-35 DEG C; the pulling speed of a 160mm * 160mm casting blank is controlled to be 1.75 m / min; the water flow of the crystallizer is controlled to be 1800 L / min; a secondary cooling water dynamic water distribution mode is weak cooling, and the water inlet temperature of secondary cooling water and crystallizer water is controlled to be 25-35 DEG C; special high-carbon high-alloy steel crystallizer casting powder is used; the casting blank with the surface temperature of 700-800 DEG C is off-line hoisted into a heat preservation pit for heat preservation, and the heat preservation pit is preheated to 200 DEG C or above in advance; according to the method, it can be guaranteed that the surface quality of the casting blank of the steel grade is stable, embrittlement does not occur in the cooling process of the casting blank, cracking does not occur in the rolling process, and the method has the advantages of being controllable, high in quality, efficient and low in cost and is suitable for large-scale industrial production of the high-carbon alloy tool steel 9SiCr.

Provided are a sulfur-resistant and corrosion-resistant low-carbon alloy-based coiled tubing and a preparation method thereof. The sulfur-resistant and corrosion-resistant low-carbon alloy-based coiled tubing is prepared by subjecting a steel strip to butt welding, curling molding, tube blank welding, extrusion molding, weld heat treatment, and cooling in sequence, and the sulfur-resistant and corrosion-resistant low-carbon alloy-based coiled tubing includes the following components by mass percentage: 0.04% to 0.08% of C, 1.5% to 2.0% of Mn, 0.1% to 0.3% of Si, 0.1% to 0.3% of Cr, 0.05% to 0.3% of Mo, 0.04% to 0.07% of Nb, 0.005% to 0.025% of Ti, 0.01% to 0.05% of Al, not greater than 0.3% of Ni, not greater than 0.3% of Cu, not greater than 0.02% of P, not greater than 0.02% of S, and Fe and unavoidable impurities as a balance.

The application relates to a preparation method of a low-carbon alloy steel, which comprises the following steps: carrying out converter steelmaking to obtain molten steel, adding aluminum into the molten steel for deoxidization; introducing the deoxidized molten steel into an LF furnace, blowing argon for refining to obtain refined molten steel; adding manganese iron deoxidizer into the refined molten steel for deoxidization and vanadium-nitrogen alloying; vacuum treating the alloyed molten steel, then carrying out casting and preparing into a steel billet; carrying out rough rolling, finish rolling and coiling of the steel billet to obtain a steel coil; carrying out uncoiling and straightening of the steel coil after cooling, and cutting into a preformed steel plate; carrying out solid solution treatment of the preformed steel plate, the temperature of the solid solution treatment is 900-930 DEG C, the preformed steel plate is cooled after the solid solution treatment, the cooling rate is 50-80 DEG C / s, and a post-solid-solution steel plate is obtained; the post-solid-solution steel plate is aged at 60-80 DEG C for 3-12 h, and then naturally cooled to obtain the low-carbon alloy steel. The application can effectively improve the strength of the low-carbon alloy steel, and meanwhile ensures that the low-carbon alloy steel has excellent low-temperature toughness.