CN114606448A

CN114606448A - Wire rod for prestressed concrete spiral rib steel wire and production method thereof

Info

Publication number: CN114606448A
Application number: CN202210296566.8A
Authority: CN
Inventors: 魏福龙; 郭翔; 李勇; 蓝桂年; 华福波; 腾鹭鹭
Original assignee: Shougang Shuicheng Iron and Steel Group Co Ltd
Current assignee: Shougang Shuicheng Iron and Steel Group Co Ltd
Priority date: 2022-03-24
Filing date: 2022-03-24
Publication date: 2022-06-10

Abstract

The invention discloses a production method of a wire rod 82B-2 for a prestressed concrete spiral rib steel wire, which comprises the steps of smelting, deoxidizing alloying, LF ladle refining, continuous casting, heating, rolling and cooling. The smelting and alloying of the converter are carried out, and the weight percentage of the components is as follows: c: 0.83% -0.86%, Si: 0.15% -0.35%, Mn: 0.60-0.90%, P is less than or equal to 0.020%, S is less than or equal to 0.015%, Cr: 0.20-0.30 percent, and the balance of iron. The product obtained by the method has stable performance, the tensile strength Rm of the product is more than or equal to 1180MPa, the section expansion rate Z reaches more than 35 percent, and the method can be used for manufacturing the 1570MPa prestressed concrete spiral rib steel wire.

Description

Wire rod for prestressed concrete spiral rib steel wire and production method thereof

Technical Field

The invention relates to the technical field of concrete steel wire processing, in particular to a wire rod for a prestressed concrete spiral rib steel wire and a production method thereof.

Background

The spiral ribbed steel wire for prestressed concrete has wide application field, and is widely applied to structural engineering such as highway and railway bridges, sleepers, electric poles, pressure water pipes, storage tanks, water towers, high-rise buildings, underground buildings, high-rise structures, hydraulic structures, ocean structures and the like. At present, the raw material of the prestressed concrete spiral rib steel wire is mainly a SWRH82B high-quality carbon steel wire rod, and the strength of the spiral rib steel wire in the production process cannot meet the standard requirement, for example, the increase of alloy elements brings the increase of production cost. In the prior art, the research aiming at the use of self-reinforcement of steel wires and concrete is less, for example, the invention name-a method for reinforcing a concrete beam by combining a prestressed steel wire bundle and carbon fiber cloth, the application number-CN201710108767. X, a steel bar screw is penetrated on the steel wire bundle, the prestressed carbon fiber cloth is bound by a web plate, and the web plate and the steel bar screw are fixed by bolts; the structure after strengthening is protected and treated, and the material combination is mainly used to carry out the reinforcement of wholeness, leads to the effect of steel wire to be on the side of supplementarily, does not maximize the efficiency that exerts the steel wire, and overall structure strengthens and also receives the restriction. Also, as the title of the invention, a local upset high strength steel wire and a method for producing the same, application No. CN201410167616.8, the local upset shape of the steel wire may be spherical, ellipsoidal or other polygonal, the corresponding longitudinal section shape is circular, elliptical or other polygonal, and other parts may be installed on the steel wire for anchor rods, precast concrete members, guy cables and hanger rods, storage racks, etc. The local deformation of the steel wire achieves a new use effect, and the reinforcement of the steel wire is not enough essentially. It can be seen that the application of steel wire to concrete by improving its strength is now necessary.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a wire rod for a prestressed concrete spiral rib steel wire and a using method thereof, which are used for improving the strength and toughness of the steel wire, enabling the steel wire to have strong binding force in concrete and improving the stability of the concrete. The method comprises the following steps:

a wire rod for a prestressed concrete spiral rib steel wire is composed of the following elements in percentage by weight:

c: 0.83% -0.86%, Si: 0.15% -0.35%, Mn: 0.60-0.90%, P is less than or equal to 0.020%, S is less than or equal to 0.015%, Cr: 0.20-0.30 percent, and the balance of iron.

Preferably, the wire rod for the prestressed concrete spiral rib steel wire is composed of the following elements in percentage by weight:

c: 0.84% -0.86%, Si: 0.15% -0.31%, Mn: 0.62-0.88%, P is less than or equal to 0.014%, S is less than or equal to 0.015%, Cr: 0.20-0.28 percent, and the balance of iron.

The invention relates to a wire rod for a prestressed concrete spiral rib steel wire, which is produced by the following steps:

(1) blast furnace smelting: putting the raw materials into a blast furnace according to the mass ratio for reduction reaction, and controlling the element composition of the molten iron components in percentage by weight to reach: si: 0.30% -0.80%, Mn: 0.30% -0.80%, Cr: 0.20% -0.30%, Ni: 0.05-0.06%, P is less than or equal to 0.120%, S is less than or equal to 0.040%, and the balance is iron content;

(2) smelting in a converter

Total converter charge: 92 +/-0.5 ton, the oxygen lance working oxygen pressure is 0.75-0.95 MPa, the oxygen purity is more than or equal to 99.5 percent, and the total oxygen pressure is more than or equal to 1.3 MPa; the converter adopts a double-slag method: 1/2 of total lime is added after ignition, 500kg of sludge balls are added, deslagging is carried out after blowing for about 6min, and slag is foamed by adopting high gun position operation before deslagging, so that deslagging amount is not less than 1/2; after deslagging, blowing and adding 200kg of fluorite, and adding two batches of materials for slagging; adopting a carburant for recarburization, and carrying out steel tapping by a converter with ferro-silico-manganese and ferrochrome;

(3) LF ladle refining: after the components of the molten steel smelted by the converter are adjusted by an LF ladle refining furnace, the steel billet has the following chemical components in percentage by weight: 0.83% -0.86%, Si: 0.15% -0.35%, Mn: 0.60-0.90%, P is less than or equal to 0.020%, S is less than or equal to 0.015%, Cr: 0.20-0.30 percent, and the balance of iron content;

(4) rolling a steel billet: the molten steel is cast into a square billet, rolled on a Danieli high-speed wire rod rolling mill and then slowly cooled;

(5) controlling the overall dimension of the wire rod product: the diameter of the finished wire rod is 12.7 mm plus or minus 0.20mm, and the out-of-roundness is less than or equal to 0.32 mm.

Preferably, in the step (2), the alkalinity after ignition is 2.4-2.8.

Preferably, in the step (2), the final slag alkalinity is 3.5.

Preferably, in the step (2), the tapping temperature is 1590-.

Preferably, in the step (4), the square billet specification is 160mm × 160 mm.

Preferably, in the step (4), the initial rolling temperature of the billet is 1000-1100 ℃, the final rolling temperature is 950-1050 ℃, the spinning temperature is 800-900 ℃, and the air-cooling final cooling temperature is 550-650 ℃.

Preferably, in the step (4), the tensile strength Rm of the produced wire rod product is more than or equal to 1180MPa, the section expansion rate Z reaches more than 35 percent, and the wire rod product is used for manufacturing a 1570MPa prestressed concrete spiral rib steel wire.

Compared with the prior art, the invention has the technical effects that:

compared with the prior art, the invention has obvious beneficial effects, and the technical scheme can show that: carbon, silicon, manganese and chromium are used as main strengthening elements, so that the production cost is reduced; the tensile strength of the steel is improved by improving the carbon content in the wire rod and effectively utilizing the structure strengthening effect of carbon on the steel; by adjusting the size of the wire rod, the size of the wire rod is enlarged while the wire rod is produced to be phi 12.5mm, the original rolling pass and the original frame are not changed, the diameter of the finished wire rod is 12.7 +/-0.20 mm, the out-of-roundness is less than or equal to 0.32mm, and the strength of the prestressed concrete spiral rib steel wire is improved by improving the deformation in the drawing process. The produced product has stable performance, the tensile strength Rm of the product is more than or equal to 1180MPa, the section expansion rate Z reaches more than 35 percent, and the product can be used for manufacturing 1570MPa prestressed concrete spiral rib steel wires.

Detailed Description

The technical solution of the present invention is further defined below with reference to the specific embodiments, but the scope of the claims is not limited to the description.

To verify the invention, the following comparative examples were set up:

comparative example 1, the difference with example 1 is that in the elements of the weight percentage of the molten iron components: mn: 1.80%, and other operations are unchanged;

comparative example 2, the difference with example 1 is that in the elements of the weight percentage of the molten iron components: ni: 0.26%, and other operations are unchanged;

comparative example 3, the difference with example 1 is that in the elements of the weight percentage of the molten iron components: cr: 1.30%, and the other operations are unchanged;

comparative example 4, the difference with example 1 is that the spinning temperature is 990 ℃, and other operations are not changed;

comparative example 5 differs from example 1 in that the air-cooled final cooling temperature is 750 ℃ and the other operations are not changed.

The example settings were as follows:

a production method of a wire rod for a prestressed concrete spiral rib steel wire comprises the following steps:

(1) blast furnace smelting: by carrying out reduction reaction in a blast furnace, the molten iron comprises the following components in percentage by weight: si: 0.30% -0.80%, Mn: 0.30% -0.80%, Cr: 0.20% -0.30%, Ni: 0.05 to 0.06 percent, less than or equal to 0.120 percent of P, less than or equal to 0.040 percent of S and the balance of iron.

The specific blast furnace ironmaking water composition is shown in the following table:

examples	Si/％	Mn/％	P/％	S/％	Cr/％	Ni/％
							1	0.30	0.45	0.111	0.017	0.22	0.058
2	0.39	0.30	0.116	0.038	0.25	0.056
							3	0.37	0.52	0.111	0.021	0.24	0.055
4	0.34	0.80	0.112	0.028	0.20	0.050
							5	0.80	0.53	0.120	0.025	0.25	0.056
6	0.74	0.49	0.11	0.030	0.30	0.060
							7	0.32	0.72	0.111	0.040	0.23	0.059
8	0.69	0.41	0.11	0.016	0.28	0.060
							9	0.43	0.41	0.106	0.018	0.23	0.060
10	0.35	0.38	0.107	0.031	0.27	0.055
							11	0.42	0.41	0.11	0.016	0.30	0.050

(2) Smelting in a converter

Total converter charge: 92 +/-0.5 ton, and the molten iron ratio is adjusted according to the heat condition. The working oxygen pressure of the oxygen lance is 0.75-0.95 MPa, the oxygen purity is more than or equal to 99.5%, and the total oxygen pressure is more than or equal to 1.3 MPa; the converter adopts a double-slag method: 1/2 (controlling the alkalinity to be 2.4-2.8) of the total lime is added after ignition, 500kg of sludge balls are added, deslagging is carried out for about 6min by blowing, and the slag is foamed by adopting high-gun-position operation before deslagging, so that the deslagging amount is not less than 1/2. After deslagging, blowing and adding 200kg of fluorite, adding two batches of materials for slagging, and controlling the alkalinity of final slag to be about 3.5; the recarburizing agent is adopted for recarburizing, ferro-silico-manganese is mixed with manganese, and the tapping temperature of the ferrochrome and chromium converter is 1590-.

The following table shows the tapping temperature of the converter and the alloy addition condition:

(3) LF ladle refining: after the components of the molten steel smelted by the converter are adjusted by an LF ladle refining furnace, the steel billet has the following chemical components in percentage by weight: 0.83% -0.86%, Si: 0.15% -0.35%, Mn: 0.60-0.90%, P is less than or equal to 0.020%, S is less than or equal to 0.015%, Cr: 0.20-0.30 percent, and the balance of iron.

The actual production chemistry is as follows:

examples	C/％	Si/％	Mn/％	P/％	S/％	Cr/％
							1	0.855	0.260	0.777	0.020	0.010	0.253
2	0.840	0.230	0.700	0.017	0.009	0.260
							3	0.850	0.240	0.650	0.018	0.011	0.205
4	0.840	0.210	0.850	0.015	0.012	0.280
							5	0.847	0.350	0.700	0.018	0.010	0.250
6	0.851	0.220	0.670	0.020	0.008	0.230
							7	0.850	0.210	0.850	0.017	0.010	0.250
8	0.850	0.210	0.691	0.021	0.015	0.200
							9	0.840	0.220	0.685	0.020	0.013	0.210
10	0.845	0.220	0.850	0.019	0.014	0.220
							11	0.839	0.230	0.677	0.020	0.010	0.220

(4) Rolling a steel billet: the molten steel is cast into a square billet of 160mm multiplied by 160mm and then rolled on a high-speed wire rolling mill of Danieli, the initial rolling temperature is 1000-1100 ℃ when rolling the billet, the final rolling temperature is 950-1050 ℃, the spinning temperature is 800-900 ℃, the air-cooled final cooling temperature is 550-650 ℃, and then the billet is slowly cooled.

The specific parameter values are as follows:

The specific parameter values are as follows:

examples	Finished wire rod diameter/mm	Wire rod out-of-roundness/mm
			1	12.78	0.20
2	12.68	0.30
			3	12.88	0.10
4	12.59	0.25
			5	12.55	0.24
6	12.88	0.27
			7	12.76	0.30
8	12.73	0.29
			9	12.78	0.25
10	12.70	0.24
			11	12.85	0.28

The produced wire rod for the prestressed concrete spiral rib steel wire has stable performance, the tensile strength Rm of the product is more than or equal to 1180MPa, the section expansion rate Z reaches more than 35 percent, and the wire rod can be used for manufacturing the prestressed concrete spiral rib steel wire with 1570 MPa. The mechanical properties of the wire rod are as follows:

group of	Tensile strength Rm/MPa	Reduction of area Z/%)
			Example 1	1185	38
Example 2	1190	40
			Example 3	1230	36
Example 4	1200	35
			Example 5	1190	39
Example 6	1185	38.5
			Example 7	1200	37
Example 8	1220	36
			Example 9	1210	37.5
Example 10	1200	38
			Example 11	1185	39
Comparative example 1	1032	33
			Comparative example 2	1011	34
Comparative example 3	1049	31
			Comparative example 4	998	25
Comparative example 5	982	27

The wire rod for the steel wire manufactured by the scheme of the invention has excellent performance and can be suitable for various scenes.

Claims

1. A wire rod for a prestressed concrete spiral rib steel wire is characterized by comprising the following elements in percentage by weight:

2. The wire rod for a prestressed concrete spiral rib steel wire according to claim 1, which is composed of the following elements by weight:

3. The wire rod for a prestressed concrete spiral rib steel wire according to claim 1, which is produced by the following method:

(1) blast furnace smelting: putting the raw materials into a blast furnace according to the mass ratio for reduction reaction, and controlling the element composition of the molten iron components in percentage by weight to reach: si: 0.30% -0.80%, Mn: 0.30% -0.80%, Cr: 0.20% -0.30%, Ni: 0.05 to 0.06 percent, less than or equal to 0.120 percent of P, less than or equal to 0.040 percent of S and the balance of iron;

(2) smelting in a converter

Total converter charge: 92 +/-0.5 ton, the oxygen lance working oxygen pressure is 0.75-0.95 MPa, the oxygen purity is more than or equal to 99.5 percent, and the total oxygen pressure is more than or equal to 1.3 MPa; the converter adopts a double-slag method: 1/2 of total lime is added after ignition, 500kg of sludge balls are added, deslagging is carried out for about 6min by blowing, and high lance position operation is adopted to foam slag before deslagging, so that deslagging amount is not less than 1/2; after deslagging, blowing and adding 200kg of fluorite, and adding two batches of materials for slagging; adopting a carburant for recarburization, and carrying out steel tapping by a converter with ferro-silico-manganese and ferrochrome;

4. The method for producing a wire rod for a prestressed concrete spiral rib steel wire according to claim 3, wherein in the step (2), the basicity after ignition is 2.4 to 2.8.

5. The method for producing a wire rod for a prestressed concrete spiral rib steel wire according to claim 3, wherein in the step (2), the basicity of the final slag is 3.5.

6. The method for producing a wire rod for a prestressed concrete spiral ribbed steel wire according to claim 3, wherein in the step (2), the tapping temperature is 1590-.

7. The method for producing a wire rod for a prestressed concrete spiral rib steel wire according to claim 3, wherein in the step (4), the billet gauge is 160mm x 160 mm.

8. The method for producing a wire rod for a prestressed concrete spiral ribbed steel wire as recited in claim 3, wherein in the step (4), the initial rolling temperature for the billet rolling is 1000-1100 ℃, the final rolling temperature is 950 ℃ -1050 ℃, the spinning temperature is 800 ℃ -900 ℃, and the air-cooled final cooling temperature is 550 ℃ -650 ℃.

9. The method for producing the wire rod for the prestressed concrete spiral rib steel wire according to claim 3, wherein in the step (4), the tensile strength Rm of the produced wire rod product is more than or equal to 1180MPa, the section expansion rate Z reaches 35%, and the wire rod product is used for manufacturing 1570MPa prestressed concrete spiral rib steel wire.