CN111112353A - Steel strand and manufacturing method and application thereof - Google Patents
Steel strand and manufacturing method and application thereof Download PDFInfo
- Publication number
- CN111112353A CN111112353A CN201911295351.9A CN201911295351A CN111112353A CN 111112353 A CN111112353 A CN 111112353A CN 201911295351 A CN201911295351 A CN 201911295351A CN 111112353 A CN111112353 A CN 111112353A
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- China
- Prior art keywords
- steel strand
- wire rod
- treatment
- preparation
- phosphating
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C1/00—Manufacture of metal sheets, metal wire, metal rods, metal tubes by drawing
- B21C1/02—Drawing metal wire or like flexible metallic material by drawing machines or apparatus in which the drawing action is effected by drums
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C43/00—Devices for cleaning metal products combined with or specially adapted for use with machines or apparatus provided for in this subclass
- B21C43/02—Devices for cleaning metal products combined with or specially adapted for use with machines or apparatus provided for in this subclass combined with or specially adapted for use in connection with drawing or winding machines or apparatus
-
- D—TEXTILES; PAPER
- D07—ROPES; CABLES OTHER THAN ELECTRIC
- D07B—ROPES OR CABLES IN GENERAL
- D07B1/00—Constructional features of ropes or cables
- D07B1/06—Ropes or cables built-up from metal wires, e.g. of section wires around a hemp core
Abstract
The invention provides a steel strand and a preparation method and application thereof, wherein the preparation method comprises the following steps: (1) surface treatment: carrying out acid washing and phosphating treatment on the wire rod; (2) drawing: drawing the wire rod in multiple passes to obtain a semi-finished steel wire; (3) twisting: stranding the central silk and the outer layer silk; (4) and (3) stabilizing treatment: applying a tension of 20-90kN to the steel strand, and stabilizing at a certain heating temperature at a linear speed of 15-30 m/min. The tensile strength of the steel strand manufactured by the invention reaches more than 1760MPa, the maximum force elongation reaches 7.6-8.45%, and compared with the elongation of 3.5% of the traditional steel strand, the elongation is improved by more than 1 time, and the steel strand is applied to the field of coal mine support, so that the safety of a coal mine can be greatly improved.
Description
Technical Field
The invention belongs to the technical field of steel strand preparation, and particularly relates to a high-strength and high-elongation steel strand as well as a preparation method and application thereof.
Background
At present, the raw materials used for manufacturing the traditional steel strand are common high-quality non-twist cold-control high-heat-rolling wire rods, the grade of the steel is SWRH82B, the content of oxygen and nitrogen in the steel is higher, the content of sulfur and phosphorus impurities is less than or equal to 0.035%, the tensile strength of the manufactured steel strand is about 1720MPa, and the maximum force elongation is about 3.5%. The tensile strength and the elongation of the traditional steel strand are difficult to reach the standard of higher tensile strength and elongation at the same time, some manufacturers usually reduce the tensile strength in order to improve the elongation, and some manufacturers are opposite to the conventional manufacturers.
When the traditional steel strand is used for supporting a mine rock burst roadway or a deep soft rock roadway, the steel strand is easy to break and lose efficacy, the main reason is that the traditional steel strand is low in elongation rate, particularly low in instantaneous elongation rate under dynamic load, when the steel strand is subjected to large deformation of soft rock or rock burst, the elongation performance and energy absorption capacity of the steel strand are not matched with underground geological conditions, the steel strand can break and lose efficacy, and therefore the roadway supporting effect is influenced. In order to increase the elongation of a common steel strand, some scholars install a transverse resistance extension device at the tail of the steel strand, and the elongation of the steel strand is improved through the friction effect of the structure, but the structure has the disadvantages of complex process, poor reliability, high cost and low construction efficiency.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides the high-strength and high-elongation steel strand and the preparation method thereof, and the steel strand is suitable for a mine rock burst roadway or a deep soft rock roadway and meets the requirement of coal mine safety mining.
Specifically, the invention provides the following technical scheme:
a preparation method of a high-strength and high-elongation steel strand comprises the following steps:
(1) surface treatment: carrying out acid washing and phosphating treatment on the wire rod;
(2) drawing: drawing the wire rod in multiple passes to obtain a semi-finished steel wire;
(3) twisting: stranding the central silk and the outer layer silk;
(4) and (3) stabilizing treatment: applying a tension of 20-90kN to the steel strand, and stabilizing at a certain heating temperature at a linear speed of 15-30 m/min.
Preferably, in the preparation method, in the step (1), the wire rod is a twist-free controlled hot and cold rolled wire rod with the trade name of SWRH82B, and preferably, the twist-free controlled hot and cold rolled wire rod has a sulfur content of 0.015% or less and a phosphorus content of 0.015% or less.
Preferably, in the preparation method, in the step (1), the solution used in the acid washing step is hydrochloric acid with a mass concentration of 8-20%, the acid washing time is 10-25min, and the technological parameters of the phosphating step are as follows: the total acidity of the phosphating solution is not less than 100 points, the free acid is 7-20 points, the temperature is 65-80 ℃, and the phosphating time is 3-7 min.
Preferably, in the above preparation method, in the step (2), the wire rod is continuously drawn in nine passes at a drawing speed of 3.5 to 4.0m/s with a reduction ratio of 14 to 22% in each pass.
Preferably, in the preparation method, in the step (3), the lay length is 240mm, preferably 230mm and 225-.
Preferably, in the above production method, in the step (4), the tension is 20 to 30 kN.
Preferably, in the preparation method, in the step (4), the heating temperature of the stabilizing treatment is 440 to 450 ℃.
Preferably, the preparation method comprises the following steps:
(1) surface treatment: carrying out acid washing and phosphating treatment on the twist-free controlled hot and cold rolled wire rod with the mark of SWRH 82B;
(2) drawing: carrying out nine-pass continuous drawing on the wire rod processed in the step (1), wherein the drawing speed is 3.5-4.0m/s, and the reduction rate of each pass is controlled within the range of 14-22%, so as to obtain a semi-finished steel wire;
(3) twisting: stranding the central silk and the outer layer silk, wherein the lay length is 225 mm;
(4) and (3) stabilizing treatment: the steel strand is applied with a tension of 20-30kN and is stabilized at a temperature of 440-450 ℃ at a linear speed of 15 m/min.
The invention also provides a high-strength and high-elongation steel strand which is prepared by the preparation method.
The invention also provides the application of the steel strand or the steel strand prepared by the preparation method in the field of support of mine rock burst roadways or deep soft rock roadways.
The invention has the following beneficial effects:
the tensile strength of the steel strand manufactured by the invention reaches more than 1760MPa, the maximum force elongation reaches 7.6-8.45%, and the elongation is improved by more than 1 time compared with the elongation of 3.5% of the traditional steel strand. The steel strand manufactured by the method is applied to the field of coal mine support, and the safety of a coal mine can be greatly improved.
Detailed Description
The present invention will be described in further detail with reference to specific examples, but the scope of the present invention is not limited thereto.
The wire rod used in the following examples is a twist-free controlled hot and cold rolled wire rod produced by Tianjin Cheng and Union iron and Steel group Limited, the diameter is phi 14mm, the mark is SWRH82B, and the specific chemical components and contents are as follows: 0.82 percent of C, 0.20 percent of Si, 0.76 percent of Mn, 0.014 percent of P and 0.010 percent of S. The wire rod is subjected to VD vacuum treatment in the manufacturing process: argon is blown from the bottom of the molten steel for manufacturing the wire rod and the molten steel is stirred, and then the molten steel is quickly vacuumized within 3min by a vacuum pump, so that the vacuum degree and the pressure are kept below 67Pa, and meanwhile, impurities in the molten steel float upwards and are cleaned in time, the molten steel subjected to VD vacuum treatment has low content of gases such as oxygen, nitrogen and the like, harmful impurities such as sulfur, phosphorus and the like are reduced, and the purity of the molten steel is greatly improved.
Example 1
1. Surface treatment: and (3) putting the wire rod into a hydrochloric acid pool with the mass concentration of 15% for acid washing for 15min, then washing with water and washing with high-pressure water, then putting the wire rod into a phosphating pool for phosphating, then washing with water and drying, and then carrying out a drawing process. The technological parameters of the phosphating treatment are as follows: the total acidity of the phosphating solution is 110 points, the free acid is 12 points, the temperature is 75 ℃, and the phosphating time is 4 min.
2. Drawing: carrying out nine-pass continuous drawing on the wire rod by adopting a straight-moving type continuous wire drawing machine with the model number of 9/1200 to obtain a semi-finished steel wire, wherein the drawing speed is controlled at 3.5m/s, and the compression ratios from the first pass to the ninth pass are as follows in sequence: 16.41%, 19.00%, 20.83%, 19.96%, 19.45%, 18.72%, 18.22%, 17.62%, 17.84%.
3. Twisting: respectively carrying out shaft beating on 1 central yarn and 18 outer layer yarns, and stranding by adopting a DN3(1+9+9) stranding machine, wherein the lay length is 240 mm.
4. And (3) stabilizing treatment: the steel strand was subjected to 90kN tension, stabilized by a 440-450 ℃ heating furnace at a linear velocity of 30m/min, and then cooled with water to obtain a steel strand of 21.8mm in diameter according to the present example.
The steel strand prepared in example 1 has a tensile strength of 1770Mpa and a maximum force elongation of 7.6% by detection. The detection method of the tensile strength and the maximum force elongation rate is based on the following steps: GB/T21839 + 2008 & ltSteel test method for prestressed concrete & gt.
Example 2
Example 2 a steel strand was prepared in the same manner as in example 1, except that: the lay length in example 2 was 225 mm.
The steel strand prepared in example 2 is detected to have the tensile strength of 1772Mpa and the maximum force elongation of 7.95%.
Example 3
Example 3 a steel strand was prepared in the same manner as in example 1, except that: in example 3, the lay length was 225mm and the line speed was 25 m/min.
The steel strand prepared in example 3 has tensile strength of 1760Mpa and maximum force elongation of 8.03% through detection.
Example 4
Example 4 a steel strand was prepared in the same manner as in example 1, except that: in example 4, the lay length was 225mm, the line speed was 25m/min, and the tension was 50 kN.
The steel strand prepared in example 4 has a tensile strength of 1772Mpa and a maximum elongation of 8.05% by detection.
Example 5
Example 5 a steel strand was prepared in the same manner as in example 1, except that: in example 5, the lay length was 225mm, the line speed was 20m/min, and the tension was 50 kN.
The steel strand prepared in example 5 is detected to have the tensile strength of 1775Mpa and the maximum force elongation of 8.15%.
Example 6
Example 6 a steel strand was prepared in the same manner as in example 1, except that: in example 6, the lay length was 225mm, the line speed was 15m/min, and the tension was 90 kN.
The steel strand prepared in example 6 has tensile strength of 1762Mpa and maximum force elongation of 8.10% by detection.
Example 7
Example 7 a steel strand was prepared in the same manner as in example 1, except that: in example 7, the lay length was 225mm, the line speed was 30m/min, and the tension was 20 kN.
The steel strand prepared in example 7 was tested to have a tensile strength of 1775Mpa and a maximum elongation of 8.07%.
Example 8
Example 8 a steel strand was prepared in the same manner as in example 1, except that: in example 8, the lay length was 225mm, the line speed was 15m/min, and the tension was 30 kN.
The steel strand prepared in example 8 was tested to have a tensile strength of 1782Mpa and a maximum elongation of 8.30%.
Example 9
Example 9 a steel strand was prepared in the same manner as in example 1, except that: in example 9, the lay length was 225mm, the line speed was 15m/min, and the tension was 20 kN.
The steel strand prepared in example 9 was tested to have a tensile strength of 1785Mpa and a maximum elongation of 8.45%.
In summary, the tensile strength of the steel strand manufactured in the embodiments 1 to 9 of the present invention reaches more than 1760MPa, the maximum force elongation reaches 7.6 to 8.45%, and the elongation is increased by more than 1 time compared with the elongation of the conventional steel strand of 3.5%. Further, by comparison, the performance of the steel strands of examples 8 and 9 is obviously better than that of examples 1 to 7, so the process parameters are optimized as follows: lay length: 225mm, speed: 15m/min, tempering temperature: 440 ℃ and 450 ℃, tension: 20-30kN, the tensile strength of the obtained finished product is as follows: 1782-: 8.3 to 8.45 percent.
Although the invention has been described in detail hereinabove by way of general description, specific embodiments and experiments, it will be apparent to those skilled in the art that many modifications and improvements can be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.
Claims (10)
1. The preparation method of the steel strand is characterized by comprising the following steps of:
(1) surface treatment: carrying out acid washing and phosphating treatment on the wire rod;
(2) drawing: drawing the wire rod in multiple passes to obtain a semi-finished steel wire;
(3) twisting: stranding the central silk and the outer layer silk;
(4) and (3) stabilizing treatment: applying a tension of 20-90kN to the steel strand, and stabilizing at a certain heating temperature at a linear speed of 15-30 m/min.
2. The method according to claim 1, wherein in step (1), the wire rod is a twist-free controlled hot and cold rolled wire rod under the designation SWRH82B, and preferably, the twist-free controlled hot and cold rolled wire rod has a sulfur content of 0.015% or less and a phosphorus content of 0.015% or less.
3. The preparation method according to claim 1 or 2, wherein in the step (1), the solution used in the acid washing process is hydrochloric acid with a mass concentration of 8-20%, the acid washing time is 10-25min, and the process parameters of the phosphating process are as follows: the total acidity of the phosphating solution is not less than 100 points, the free acid is 7-20 points, the temperature is 65-80 ℃, and the phosphating time is 3-7 min.
4. The production method according to any one of claims 1 to 3, wherein in the step (2), the wire rod is continuously drawn in nine passes at a drawing speed of 3.5 to 4.0m/s with a reduction ratio of each pass controlled within a range of 14 to 22%.
5. The preparation method according to any one of claims 1 to 4, wherein, in step (3), the lay length is 225-240mm, preferably 225-230 mm.
6. The production method according to any one of claims 1 to 5, wherein, in the step (4), the tension is 20 to 30 kN.
7. The production method according to any one of claims 1 to 6, wherein in the step (4), the heating temperature of the stabilization treatment is 440 to 450 ℃.
8. The production method according to any one of claims 1 to 7, comprising the steps of:
(1) surface treatment: carrying out acid washing and phosphating treatment on the twist-free controlled hot and cold rolled wire rod with the mark of SWRH 82B;
(2) drawing: carrying out nine-pass continuous drawing on the wire rod processed in the step (1), wherein the drawing speed is 3.5-4.0m/s, and the reduction rate of each pass is controlled within the range of 14-22%, so as to obtain a semi-finished steel wire;
(3) twisting: stranding the central silk and the outer layer silk, wherein the lay length is 225 mm;
(4) and (3) stabilizing treatment: the steel strand is applied with a tension of 20-30kN and is stabilized at a temperature of 440-450 ℃ at a linear speed of 15 m/min.
9. A steel strand, characterized by being produced by the production method according to any one of claims 1 to 8.
10. Use of a steel strand according to claim 9 or a steel strand prepared by the preparation method according to any one of claims 1 to 8 in the field of supporting of mine rock burst roadways or deep soft rock roadways.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911295351.9A CN111112353B (en) | 2019-12-16 | 2019-12-16 | Steel strand and manufacturing method and application thereof |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911295351.9A CN111112353B (en) | 2019-12-16 | 2019-12-16 | Steel strand and manufacturing method and application thereof |
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| CN111112353A true CN111112353A (en) | 2020-05-08 |
| CN111112353B CN111112353B (en) | 2021-10-01 |
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Effective date of registration: 20211228 Address after: Tiandi building, Coal Research Institute, No.5, Qingnian Gou Road, Chaoyang District, Beijing 100013 Patentee after: TIANDI SCIENCE & TECHNOLOGY Co.,Ltd. Patentee after: Tianjin Dejia prestressed steel strand Co., Ltd Address before: Tiandi building, Coal Research Institute, No.5, Qingnian Gou Road, Chaoyang District, Beijing 100013 Patentee before: TIANDI SCIENCE & TECHNOLOGY Co.,Ltd. |