Method of production of rolled blanks

FIELD: metallurgy; production of important rolled stock for oil-well tubing of increased service life.

SUBSTANCE: proposed method includes making steel of definite chemical composition in electric furnace, tapping metal from furnace into ladle, treatment of metal in ladle and teeming steel into ingot molds. Alloying with molybdenum is performed by introducing molybdenum-containing materials into furnace in making steel. After teeming, ingots are rolled, cooled and heated for rolling in preset temperature range and are subjected to preliminary and final deformation; process is completed by final cooling of rolled blanks to surrounding temperature.

EFFECT: improved strength characteristics and cold resistance of metal; enhanced reliability of metal products.

1 ex

 

The invention relates to metallurgy, and more specifically to the production of critical rolled products for the manufacture of tubing with increased resource use.

The known method of steel production, including steel smelting, casting, austenization, preliminary and final deformation, heat treatment and final cooling of the rental (ed. St. USSR N 1611952, CL 21 D 8/00, 1988-equivalent).

The closest in technical essence and the achieved result is a method of production of rolled billets, including steel smelting, alloying and bucket processing, steel casting, the austenization and rolling ingot, cooling blooms, preliminary and final deformation, as well as the final cooling of the workpieces (RF patent N 2156312, CL 21 D 8/02, 2000 - prototype).

The main disadvantages of known methods (analogue and prototype) are not sufficiently high level of strength and plastic properties and cold resistance metal blanks.

The technical result of the invention consists in improving the strength properties and cold resistance metal blanks, which leads to improved performance and reliability of final products.

The technical result is achieved in that in the method of manufacturing rolled in the title is set, includes steel smelting, alloying and bucket processing, steel casting, heat for rolling, preliminary and final deformation, cooling of workpieces, according to the invention alloying steel with molybdenum carried out by entering a molybdenum-containing materials into the furnace for steelmaking and get the steel of the following chemical composition in the ratio of ingredients, wt.%:

Carbon 0,42-0,54

Manganese 0,90-1,50

Silicon 0,15-0,50

Niobium 0,01-0,08

Molybdenum 0,06-0,20

Sulfur 0,001-0,045

Phosphorus 0,001-0,045

Iron Rest

the heating for rolling is carried out before the temperature 1250-1290°C.

Introduction molybdenum-containing materials into the furnace for steelmaking due to the most complete and uniform absorption, with less going into slag compared to other methods of its introduction in the steel in the ladle during the period of release of the metal from the furnace or finishing metal)that provides the desired combination of strength and viscous properties of the metal.

The choice of temperature range of heating the metal under the rolling caused by the necessity to provide the most complete transition in solid solution carbides and carbonitrides of niobium, excluding the strong growth of austenitic grains.

Heating the metal before rolling below 1250°leads to incomplete transition carbides and nitrides of niobium in solid solution. The consequence is of this is the intensive grain boundary hardening of metal as in the prior, and during the final deformation; the result of which are provided with high strength and cold-resistant properties in low plasticity.

When heated before deformation above 1290°With intense growth of austenite grains is not restricted by carbides and carbonitrides of niobium, resulting in larger grains of ferrite and a decrease in strength and toughness of metal.

It was established experimentally that the selected parameters of the proposed method provide rental with an increased range of mechanical properties for strength, plastic and cold-resistant performance.

An example of the method.

Steel was smelted in the electric furnace. Alloying steel with molybdenum was carried out in the process of steel smelting in the furnace by entering ferromolybdenum in the number of 1.30-1.70 kg/t of steel. After the release of the metal from the furnace was producing his treatment in the ladle and poured into ingot molds. When out-of-furnace processing of metal in the ladle also conducted the final deoxidation of metal, its refining, homogenizing the neutral gas blowing and modifying the processing of the silicocalcium. In the smelting and secondary treatment received steel of the following composition, wt.%: With 0,48, MP of 1.25, Si 0,34, Nb 0,04, Mo 0,09, S Of 0.004, P 0,010, iron rest. As residual elements in the steel further what about the contained wt.%: SG 0,16, Ni is 0.16, si 0.20 Ti 0,015.

Steel casting molds carried out at a temperature of 1540 -1545°C. the Ingot was kept in the molds for at least 3 hours, stripped and subjected to the austenization are determined at a temperature of 1200-1300°C for 4 hours. After austenization are determined made the rolling of ingots on the blooming and cooling blooms. Then produced heat blooms for rolling up 1250-1290°and pre-strain for 9 passages in the reverse mode and the final deformation for 7 passes with the temperature of the end of the deformation 850-900°to get rolled billets.

After the end of the deformation process was carried out by the final cooling of rolled billets to the ambient temperature.

Testing of mechanical properties of the samples showed that the use of the proposed method of production of rolled billets allows for increasing values of strength and plastic properties of 10-15% with simultaneous increase of indices of cold resistance 5 to 10%.

Method for the production of rolled billets, including steel smelting, alloying, bucket processing, steel casting, heat for rolling, preliminary and final deformation, cooling of workpieces, characterized in that exercise alloying with molybdenum by entering a molybdenum-containing materials into the furnace in the smelting article is whether and receive the steel of the following chemical composition in the ratio of ingredients, wt.%:

Carbon 0,42-0,54

Manganese 0,90-1,50

Silicon 0,15-0,50

Niobium 0,01-0,08

Molybdenum 0,06-0,20

Sulfur 0,001-0,045

Phosphorus 0,001-0,045

Iron Rest

the heating for rolling is carried out before the temperature 1250-1290°C.



 

Same patents:

FIELD: metallurgy; high-titanium-bearing foundry alloy production.

SUBSTANCE: the invention is dealt with the field of metallurgy, in particular, with production of the foundry alloy containing mainly titanium and also a small amount of other useful metals reduced from oxides of a charge together with the basic components of a foundry alloy. The method includes the following stages: after melting-down of the first portion of the charge representing an ilmenite concentrate formed on the rotating melt of the high-titanium-bearing foundry alloy and reduction by titanium and silicon of a part of oxides from the melted portion of ilmenite they use aluminum to reduce all oxides in a cinder melt. The obtained slag is added with the first portion of calcium oxide in the amount ensuring fluidity of the cinder. The second portion of the charge is introduced in the melt in the amount corresponding to the possibility of to reduce oxides by titanium. The produced titanium oxide is merged with the earlier produced cinder. A determined part of the produced melt in conditions of its rotation is poured out through a side tap hole. Using aluminum reduce titanium oxide from the merged cinder and the reduced titanium merge with the rest metal melt. In the formed final cinder enter the second portion of calcium oxide. A part of the produced foundry alloy is poured out through a side tap hole. Then a final cinder is also poured out and they feed a new portion of ilmenite onto the residue of the foundry alloy. The invention allows to reduce at least twice the power input used for reprocessing of the ilmenite concentrate, as in the process of reduction of the metals from oxides there are no endothermic reactions but exothermic reactions; to use ilmenite concentrates with a share of titanium oxide up to 45% and a strong metal reductant - aluminum, and also to realize a progressive technology of the liquid-phase reduction of metals from oxides in conditions of rotation of the melt by an electromagnetic field.

EFFECT: the invention allows to reduce at least twice the power input used for reprocessing of the ilmenite concentrate, to use ilmenite concentrates with a share of titanium oxide up to 45% and a strong metal reductant - aluminum, to realize a progressive technology of the liquid-phase reduction of metals from oxides.

5 cl, 1 ex, 1 dwg

FIELD: ferrous metallurgy.

SUBSTANCE: invention provides round-profiled iron smelted from low-carbon steel composed of, wt %: carbon 0.17-0.25, manganese 0.30-0.65, silicon 0.01-0.17, sulfur 0.005-0.020, vanadium 0.005-0.07, niobium 0.005-0.02, calcium 0.001-0.010, iron and unavoidable impurities - the balance. When following relationships are fulfilled: 12/C-Mn/0.02 ≥ 27; 0.46 ≥ 6V+8Nb ≥ 0.22; Ca/S ≥ 0.065, rolled iron has following characteristics: maximum degree of pollution with nonmetal inclusions, in particular sulfides, oxides, silicates, and nitrides, does not exceed 3 points for each type of inclusions; longitudinally uniform spheroidized structure composed of at least 80% grainy perlite; effective grain size 5-10 points; diameter 10-25 mm; carbon-free layer not exceeding 1.5% of diameter; cold setting value at least 1/3 height; point of maximum load not higher than 550 MPa; relative elongation at least 20%; and relative contraction at least 60%.

EFFECT: ensured optimal conditions for cold die forging of high-strength geometrically complex fastening members and simultaneously ensured improved characteristics of in-process plasticity and low level of stray hardening.

FIELD: ferrous metallurgy.

SUBSTANCE: invention provides round-profiled iron smelted from alloyed steel composed of, wt %: carbon 0.06-0.11, manganese 0.30-0.9, silicon 0.001-0.15, boron 0.0005-0.0050, vanadium 0.005-0.08, aluminum 0.02-0.06, titanium 0.01-0.04, sulfur 0.005-0.020, nitrogen 0.005-0.015, calcium 0.001-0.010, iron and unavoidable impurities - the balance. When following relationships are fulfilled: Ti/48+Al/27-N/14 ≥ 0.6 x 10-3; Mn+5.0C ≥ 0.80; Ca/S ≥ 0.065, rolled iron has following characteristics: maximum degree of pollution with nonmetal inclusions, in particular sulfides, oxides, silicates, and nitrides, does not exceed 3 points for each type of inclusions; longitudinally uniform spheroidized structure composed of at least 60% grainy perlite; effective grain size 5-10 points; diameter 10-16 mm; carbon-free layer not exceeding 1.0% of diameter; cold setting value at least 1/3 height; throughout hardenability in circles up to 16 mm in diameter; point of maximum load not higher than 500 MPa; relative elongation at least 22%; and relative contraction at least 70%.

EFFECT: ensured optimal conditions for cold die forging of high-strength geometrically complex fastening members and simultaneously improved steel hardenability characteristics.

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FIELD: ferrous metallurgy.

SUBSTANCE: invention provides round-profiled iron smelted from medium-carbon high-plasticity steel composed of, wt %: carbon 0.27-0.32, manganese 0.30-0.50, silicon 0.01-0.37, chromium 0.01-0.25, sulfur 0.005-0.020, niobium 0.005-0.02, calcium 0.001-0.010, iron and unavoidable impurities - the balance. When following relationships are fulfilled: 12/C-Mn/0.03 ≥ 20, Ca/S ≥ 0.065, rolled iron has following characteristics: maximum degree of pollution with nonmetal inclusions, in particular sulfides, oxides, silicates, and nitrides, does not exceed 3 points for each type of inclusions; longitudinally uniform spheroidized structure composed of at least 80% grainy perlite; effective grain size 5-10 points; diameter 10-30 mm; carbon-free layer not exceeding 1.5% diameter; cold setting value at least 1/3 height; point of maximum load not higher than 620 MPa; relative elongation at least 18%; and relative contraction at least 55%.

EFFECT: ensured optimal conditions for cold die forging of high-strength geometrically complex fastening members and simultaneously ensured improved characteristics of in-process plasticity and low level of stray hardening.

FIELD: ferrous metallurgy.

SUBSTANCE: invention provides round-profiled iron smelted from low-carbon steel composed of, wt %: carbon 0.17-0.25, manganese 0.30-0.65, silicon 0.01-0.17, sulfur 0.005-0.020, vanadium 0.005-0.07, niobium 0.005-0.02, calcium 0.001-0.010, iron and unavoidable impurities - the balance. When following relationships are fulfilled: 12/C-Mn/0.02 ≥ 27; 0.46 ≥ 6V+8Nb ≥ 0.22; Ca/S ≥ 0.065, rolled iron has following characteristics: maximum degree of pollution with nonmetal inclusions, in particular sulfides, oxides, silicates, and nitrides, does not exceed 3 points for each type of inclusions; longitudinally uniform spheroidized structure composed of at least 80% grainy perlite; effective grain size 5-10 points; diameter 10-25 mm; carbon-free layer not exceeding 1.5% of diameter; cold setting value at least 1/3 height; point of maximum load not higher than 550 MPa; relative elongation at least 20%; and relative contraction at least 60%.

EFFECT: ensured optimal conditions for cold die forging of high-strength geometrically complex fastening members and simultaneously ensured improved characteristics of in-process plasticity and low level of stray hardening.

FIELD: ferrous metallurgy.

SUBSTANCE: invention provides round-profiled iron smelted from alloyed steel composed of, wt %: carbon 0.06-0.11, manganese 0.30-0.9, silicon 0.001-0.15, boron 0.0005-0.0050, vanadium 0.005-0.08, aluminum 0.02-0.06, titanium 0.01-0.04, sulfur 0.005-0.020, nitrogen 0.005-0.015, calcium 0.001-0.010, iron and unavoidable impurities - the balance. When following relationships are fulfilled: Ti/48+Al/27-N/14 ≥ 0.6 x 10-3; Mn+5.0C ≥ 0.80; Ca/S ≥ 0.065, rolled iron has following characteristics: maximum degree of pollution with nonmetal inclusions, in particular sulfides, oxides, silicates, and nitrides, does not exceed 3 points for each type of inclusions; longitudinally uniform spheroidized structure composed of at least 60% grainy perlite; effective grain size 5-10 points; diameter 10-16 mm; carbon-free layer not exceeding 1.0% of diameter; cold setting value at least 1/3 height; throughout hardenability in circles up to 16 mm in diameter; point of maximum load not higher than 500 MPa; relative elongation at least 22%; and relative contraction at least 70%.

EFFECT: ensured optimal conditions for cold die forging of high-strength geometrically complex fastening members and simultaneously improved steel hardenability characteristics.

FIELD: ferrous metallurgy.

SUBSTANCE: invention provides round-profiled iron smelted from alloyed steel composed of, wt %: carbon 0.28-0.35, manganese 0.90-1.40, silicon 0.001-0.37, sulfur 0.005-0.020, chromium 0.001-0.35, vanadium 0.001-0.07, molybdenum 0.001-0.10, nickel 0.001-0.10, niobium 0.005-0.02, titanium 0.01-0.04, boron 0.0005-0.0050, aluminum 0.02-0.06, nitrogen 0.005-0.015, iron and unavoidable impurities - the balance. When following relationships are fulfilled: 12/C-Mn/0.055 ≤ 2.0; 500(Ti/24-N/7)+0.2 ≥ 0; 40 ≥ C/0.01+B/0.001 ≥ 0.33, rolled iron has following characteristics: maximum degree of pollution with nonmetal inclusions, in particular sulfides, oxides, silicates, and nitrides, does not exceed 3 points for each type of inclusions; longitudinally uniform spheroidized structure composed of at least 80% perlite; effective grain size 5-10 points; diameter of wire 10-25 mm; carbon-free layer not exceeding 1.5% diameter; cold setting value at least 1/3 height; throughout hardenability in circles up to 23 mm in diameter; point of maximum load not higher than 640 MPa; relative elongation at least 18%; and relative contraction at least 55%.

EFFECT: ensured optimal conditions for cold die forging of high-strength geometrically complex fastening members and simultaneously improved steel hardenability characteristics.

FIELD: ferrous metallurgy.

SUBSTANCE: invention provides round-profiled iron smelted from steel containing carbon and alloying elements, having specified parameters of metallurgical quality, structure, mechanical properties, hardenability, and in-process plasticity and characterized by being composed of, wt %: carbon 0.17-0.25, manganese 0.90-1.40, silicon 0.01-0.17, sulfur 0.005-0.020, chromium 0.001-0.35, vanadium 0.001-0.07, nickel 0.001-0.10, copper 0.001-0.10, molybdenum 0.001-0.10, titanium 0.01-0.04, boron 0.0005-0.0050, calcium 0.001-0.010, iron and unavoidable impurities - the balance. When following relationships are fulfilled: 22 ≤ 12/C-Mn/0.055 ≤ 47Ni/10Ti+Al ≤ 0.039; 10B-0.01C/N ≥ 1.80, rolled iron has following characteristics: maximum degree of pollution with nonmetal inclusions, in particular sulfides, oxides, silicates, and nitrides, does not exceed 3 points for each type of inclusions; longitudinally uniform spheroidized structure composed of at least 80% perlite; effective grain size 5-10 points; diameter of wire 10-25 mm; carbon-free layer not exceeding 1.5% diameter; cold setting value at least 1/3 height; throughout (90%) hardenability in circles up to 19 mm in diameter; point of maximum load not higher than 580 MPa; relative elongation at least 18%; and relative contraction at least 60%.

EFFECT: ensured optimal conditions for cold die forging of high-strength geometrically complex fastening members and simultaneously improved steel hardenability characteristics.

FIELD: ferrous metallurgy.

SUBSTANCE: invention provides round-profiled iron smelted from steel containing, wt %: carbon 0.10-0.15, manganese 0.90-1.40, silicon 0.001-0.37, sulfur 0.005-0.020, chromium 0.001-0.35, nickel 0.005-0.10, niobium 0,005-0.02, titanium 0.01-0.04, boron 0.0005-0.0050, aluminum 0.02-0.06, nitrogen 0.005-0.015, iron and unavoidable impurities - the balance. When following relationships are fulfilled: 500(Ti/24-N/7)+0.2 ≥ 0; 40 ≥ C/0.01+B/0.0001 ≥ 3.0, rolled iron has following characteristics: maximum degree of pollution with nonmetal inclusions, in particular sulfides, oxides, silicates, and nitrides, does not exceed 3 points for each type of inclusions; longitudinally uniform spheroidized structure composed of at least 80% perlite; effective grain size 5-10 points; diameter of wire 10-23 mm; carbon-free layer not exceeding 2.5% diameter; cold setting value at least 1/3 height; throughout hardenability in circles up to 15 mm in diameter; point of maximum load not higher than 520 MPa; relative elongation at least 20%; and relative contraction at least 65%.

EFFECT: ensured optimal conditions for cold die forging of high-strength geometrically complex fastening members and simultaneously improved steel hardenability characteristics.

FIELD: rolled tube production, namely method for making pilger mill mandrels from heat resistant steel for rolling hot rolled tubes.

SUBSTANCE: method for making mandrels used for rolling hot rolled tubes with large and mean diameters in range 273-550mm comprises steps of casting ingots of hear resistant steel; forging cylindrical solid or hollow blanks, roughly working of them, performing heat treatment and finishing mandrels at forming conicity 1 - 2 mm on length of their working portion while taking into account designed linear expansion coefficient during rolling process; determining diameter size by means of expression δ = dn - Δ/1 + αĚt. One portion of mandrel from lock along length of half of working portion of mandrel is in the form of cone with diameters of cone bases determined form given expression and second portion is in the form of cylinder or truncated cone whose diameters are determined according to next expression

EFFECT: lowered lengthwise thickness difference of tubes.

3 cl, 1 dwg, 1 tbl

The invention relates to the field of metallurgy, in particular to the production of rolled low-carbon steel for cold massive forming geometrically-complex fasteners particularly complex form

The invention relates to the field of metallurgy, in particular to the production of rolled low-carbon steel for cold massive forming geometrically-complex fasteners

The invention relates to the field of metallurgy, in particular to the production of rolled low-carbon steel for cold massive forming fasteners particularly complex form

FIELD: iron metallurgy, in particular manufacturing of hot-rolled steel and products the same.

SUBSTANCE: method includes matrix steel smelting in steel furnace, containing carbon, manganese, silicium, and iron; tapping into ladle; introducing into bottom zone of ladle mixture for microalloying and deoxidation containing aluminum, calcium, and boron with simultaneous blasting with nitrogen through the bottom jet; and simultaneous complete of mixture introducing and nitrogen blasting; steel casting, and steel ingot producing. Ingot contains (mass %) carbon 0.12-0.42; silicium 0.17-1.10; manganese 0.5-1.8; calcium 0.001-0.02; aluminum 0.02-0.05; aluminum nitride 0.01-0.0.04; boron 0.0001-0.0005; boron nitride 0.001-0.005; nitrogen 0.005-0.012; and balance: iron and inevitable impurities. Ingot is taken out, hot rolled up to desired product dimensions and thermal hardened. Optionally (for example to produce additional rolled product characteristic such as improved tensile strength, ultimate strength, wearing capacity) steel may be additionally doped with chromium, nickel, copper, molybdenum and/or vanadium. Steel of present invention is useful for production of oil pump bars of 15-40 mm in diameter and up to 8.5 m in length.

EFFECT: steel with improved mechanical characteristics.

11 cl, 2 tbl, 1 ex

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