CN109797337A - Nonmagnetic steel ingot and its manufacturing method for pump head body - Google Patents
Nonmagnetic steel ingot and its manufacturing method for pump head body Download PDFInfo
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- CN109797337A CN109797337A CN201910059673.7A CN201910059673A CN109797337A CN 109797337 A CN109797337 A CN 109797337A CN 201910059673 A CN201910059673 A CN 201910059673A CN 109797337 A CN109797337 A CN 109797337A
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- steel ingot
- head body
- pump head
- steel
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
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Abstract
The invention discloses the nonmagnetic steel ingots and its manufacturing method for pump head body, nonmagnetic steel ingot for pump head body includes the chemical component of following weight percent: 0.45%-0.60%C, 0.30-0.80%Si, 17%-19%Mn, 3.5%-6.0%Cr, < 0.30%Ni, < 0.20%Cu, < 0.015%P, < 0.005%S, < 0.10%Mo, 0.015%-0.030%Nb, < 0.010%Sn, 0.1%-0.2%V, 0.010%-0.025%Al, < 0.010%As, < 1.7ppmH, < 25ppmO, < 70ppmN；The manufacturing method of nonmagnetic steel ingot for pump head body, comprising the following steps: the detection that chemical component is carried out to raw material is made furnace lining with basic refractory, smelted；Tapping；Liquid steel refining is carried out using white slag；Vacuum refining；Argon gas protective casting.The problem of present invention solves currently, fracturing pump pump head body corrosion resistance is poor, service life is short, at high cost, is not able to satisfy the demand of oil output and the exploitation of shale gas pressure break.
Description
Technical field
The present invention relates to a kind of pump head body steel ingots and preparation method thereof, and in particular to for pump head body nonmagnetic steel ingot and
Its manufacturing method.
Background technique
Currently, fracturing technique can effectively improve the yield of petroleum, shale gas in petroleum, shale gas exploitation field,
Fracturing pump is the key equipment in pressure break recovery process.According to the 12nd five-year-plan outline pair of national economy and social development
Manufacturing industry is promoted, optimizes structure, quality of making better products, improves fundamental technology, improves basic material R & D Level, realizing and close
The related requirement of key components technology automation etc., especially country promote production capacity to petroleum vapour well, increase yield
It is required that it is higher and higher, it is also higher and higher to the technical requirements of fracturing pump.
The performance of fracturing pump, q&r directly affect the quality and progress of pressure break implementation process, wherein fracturing pump
Pump head body is the important feature of fracturing pump；Currently, fracturing pump pump head body corrosion resistance is poor, service life is short, at high cost, it cannot
Meets the needs of oil output and exploitation of shale gas pressure break.
Summary of the invention
The technical problem to be solved by the present invention is to currently, fracturing pump pump head body corrosion resistance is poor, service life is short, at
This height is not able to satisfy the demand of oil output and the exploitation of shale gas pressure break, and it is an object of the present invention to provide a kind of superhigh intensity super high-low temperature
Fracturing pump pump head body is impacted, solves not to be able to satisfy currently, fracturing pump pump head body corrosion resistance is poor, service life is short, at high cost
The problem of oil output and the demand of shale gas pressure break exploitation.
The present invention is achieved through the following technical solutions:
For the nonmagnetic steel ingot of pump head body, the chemical component including following weight percent: 0.45%-0.60%C,
0.30-0.80%Si, 17%-19%Mn, 3.5%-6.0%Cr, < 0.30%Ni, < 0.20%Cu, < 0.015%P, <
0.005%S, < 0.10%Mo, 0.015%-0.030%Nb, < 0.010%Sn, 0.1%-0.2%V, 0.010%-
0.025%Al, < 0.010%As, < 1.7ppmH, < 25ppmO, < 70ppmN.
Present invention reduces the hydrogen content in steel, the generation of the white point in steel is prevented, avoids the generation of cold cracking, is reduced
With control oxygen content, oxide inclusion presence can be eliminated, the plasticity and toughness of steel are improved, reduces nitrogen content, it can be to avoid remnants
Aged brittleness caused by nitrogen is effectively controlled the residual volume of pernicious gas in steel.
The adjusting that the present invention is matched in the chemical constituent of steel ingot raw material improves the strong of steel ingot from raw material
Degree, corrosion resistance, the pump head body that steel ingot is process are suitble to complicated oil-gas mining environment, solve currently, pressing
Split pump pump head body corrosion resistance it is poor, service life is short, at high cost, be not able to satisfy oil output and shale gas pressure break exploitation need
The problem of asking.
The nonmagnetic steel ingot for pump head body, the chemical component including following weight percent: 0.45%-
0.55%C, 0.30-0.60%Si, 17%-19%Mn, 3.5%-4.0%Cr, < 0.10%Ni, < 0.20%Cu, <
0.010%P, < 0.005%S, < 0.10%Mo, 0.015%-0.025%Nb, < 0.010%Sn, 0.1%-0.2%V,
0.010%-0.025%Al, < 0.010%As, < 1.7ppmH, < 25ppmO, < 70ppmN.The present invention is preferential optimal
Steel ingot raw material chemical constituent proportion.
The manufacturing method of the nonmagnetic steel ingot for pump head body, comprising the following steps:
S1, electric arc furnace smelting: obtaining raw material and the detection of chemical component is carried out to raw material, makees furnace with basic refractory
Lining, is smelted, and the proportion of ingredient in molten steel is adjusted；
S2, tapping: red packet tapping is carried out with the ladle of magnesium refractory preparation；
S3, ladle refining: ladle refining furnace carries out liquid steel refining using white slag, realizes molten steel desulfurizing, deoxidation, white slag refining
Time is greater than 30 minutes, and alloy is sufficiently added in deoxidization desulfuration afterwards；Molten steel sulfur content is less than when ladle refining furnace tapping deoxidization
0.003%；
S4, vacuum refining: it is kept for 15 minutes or more under vacuum condition of the vacuum degree less than 30Pa, soft blow after vacuum
15 minutes or more；
S5, argon gas protective casting: molten steel by ladle take off into ingot mould to get to steel ingot.
The present invention has carried out the adjustment of parameter in steel ingot preparation process, and molten steel casting process is maintained at vacuum (vacuum degree
Less than 30Pa) under the conditions of carry out, effectively prevent hydrogenation and nitrogen pick-up of the molten steel in steel pouring process；Molten steel of the present invention is being poured
It is whole in the process to use argon for protecting pouring, contact of the molten steel again with air is prevented, secondary oxidation and air-breathing occurs, fully ensures that
The degree of purity and ultra low gas content of molten steel；The present invention controls ladle refining, vacuum refining time, can be improved steel ingot
Mechanical performance so that steel ingot process pump head body intensity height, corrosion resistance, impact resistance, be suitable for oil exploitation；The present invention
Obtained steel ingot ingot body is fine and close, ingredient is uniform, internal soundness is good.The present invention has carried out constituent analysis to raw material first, according to
The analysis result of raw material adjusts the proportion of each component, so that the quality for the steel ingot produced meets the needs of oil exploitation.
In electric arc furnace smelting and ladle refining process, liquid steel temperature≤1660 DEG C.Liquid steel temperature is excessively high, and gas is in steel
Solubility with regard to excessive, to steel quality harm influence it is also bigger, the present invention controls the temperature of molten steel.
Cast temperature≤1580 DEG C in step S5.The present invention reduce cast temperature in order to control tissue after solidification in steel,
The appearance for reducing adverse tissue, can be improved the quality of steel ingot.
The manufacturing method of the nonmagnetic steel ingot for pump head body, further comprising the steps of:
S6, steel ingot detection: chemical component detection, white point detection, metallographic detection, ultrasonic flaw detection inspection are carried out to steel ingot
Side；
S7, steel ingot screening: steel ingot is screened according to the following conditions according to steel ingot testing result: nonmetallic individual event in steel
Field trash is less than or equal to 1 grade, and oxide and Sulfide inclusion summation are less than or equal to 2 grades, and pattern segregation, center porosity are less than etc.
In 1 grade, it is not allow for general spot segregation and edge spot segregation exists.The present invention detects steel ingot, further controls
The quality of steel ingot.
Compared with prior art, the present invention having the following advantages and benefits:
1, the present invention has adjusted the chemical composition content in pump head body for the nonmagnetic steel ingot of pump head body, so that steel ingot adds
Pump head body made of work can be suitble to complicated oil-gas mining environment, solve currently, fracturing pump pump head body corrosion resistance it is poor,
Service life is short, at high cost, be not able to satisfy oil output and shale gas pressure break exploitation demand the problem of；
2, the present invention has carried out parameter for the manufacturing method of the nonmagnetic steel ingot of pump head body in steel ingot preparation process
Adjustment so that steel ingot process pump head body intensity height, corrosion resistance, impact resistance, suitable for oil exploitation；
The steel ingot ingot body that 3, the present invention is obtained for the manufacturing method of the nonmagnetic steel ingot of pump head body is fine and close, ingredient is uniform,
Internal soundness is good.
Specific embodiment
To make the objectives, technical solutions, and advantages of the present invention clearer, below with reference to embodiment, the present invention is made
Further to be described in detail, exemplary embodiment of the invention and its explanation for explaining only the invention, are not intended as to this
The restriction of invention.
Embodiment 1
The present invention is used for the nonmagnetic steel ingot of pump head body, the chemical component including following weight percent: 0.45%-
0.60%C, 0.30-0.80%Si, 17%-19%Mn, 3.5%-6.0%Cr, < 0.30%Ni, < 0.20%Cu, <
0.015%P, < 0.005%S, < 0.10%Mo, 0.015%-0.030%Nb, < 0.010%Sn, 0.1%-0.2%V,
0.010%-0.025%Al, < 0.010%As, < 1.7ppmH, < 25ppmO, < 70ppmN.
Present invention reduces the hydrogen content in steel, the generation of the white point in steel is prevented, avoids the generation of cold cracking, is reduced
With control oxygen content, oxide inclusion presence can be eliminated, the plasticity and toughness of steel are improved, reduces nitrogen content, it can be to avoid remnants
Aged brittleness caused by nitrogen is effectively controlled the residual volume of pernicious gas in steel.
The adjusting that the present invention is matched in the chemical constituent of steel ingot raw material improves the strong of steel ingot from raw material
Degree, corrosion resistance, the pump head body that steel ingot is process are suitble to complicated oil-gas mining environment, solve currently, pressing
Split pump pump head body corrosion resistance it is poor, service life is short, at high cost, be not able to satisfy oil output and shale gas pressure break exploitation need
The problem of asking.
Embodiment 2
Based on embodiment 1, the nonmagnetic steel ingot for pump head body, including following weight percent chemistry at
Point: 0.45%-0.55%C, 0.30-0.60%Si, 17%-19%Mn, 3.5%-4.0%Cr, < 0.10%Ni, < 0.20%
Cu, < 0.010%P, < 0.005%S, < 0.10%Mo, 0.015%-0.025%Nb, < 0.010%Sn, 0.1%-0.2%
V, 0.010%-0.025%Al, < 0.010%As, < 1.7ppmH, < 25ppmO, < 70ppmN.The present invention is preferential most preferably
Steel ingot raw material chemical constituent proportion.
Embodiment 3
Based on the above embodiment, the manufacturing method of the nonmagnetic steel ingot for pump head body, comprising the following steps:
S1, electric arc furnace smelting: obtaining raw material and the detection of chemical component is carried out to raw material, makees furnace with basic refractory
Lining, is smelted, and the proportion of ingredient in molten steel is adjusted；
S2, tapping: red packet tapping is carried out with the ladle of magnesium refractory preparation；
S3, ladle refining: ladle refining furnace carries out liquid steel refining using white slag, realizes molten steel desulfurizing, deoxidation, white slag refining
Time is greater than 30 minutes, and alloy is sufficiently added in deoxidization desulfuration afterwards；Molten steel sulfur content is less than when ladle refining furnace tapping deoxidization
0.003%；
S4, vacuum refining: it is kept for 15 minutes or more under vacuum condition of the vacuum degree less than 30Pa, soft blow after vacuum
15 minutes or more；
S5, argon gas protective casting: molten steel by ladle take off into ingot mould to get to steel ingot；
S6, steel ingot detection: chemical component detection, white point detection, metallographic detection, ultrasonic flaw detection inspection are carried out to steel ingot
Side；
S7, steel ingot screening: steel ingot is screened according to the following conditions according to steel ingot testing result: nonmetallic individual event in steel
Field trash is less than or equal to 1 grade, and oxide and Sulfide inclusion summation are less than or equal to 2 grades, and pattern segregation, center porosity are less than etc.
In 1 grade, it is not allow for general spot segregation and edge spot segregation exists.The present invention detects steel ingot, further controls
The quality of steel ingot.
In electric arc furnace smelting and ladle refining process, liquid steel temperature≤1660 DEG C.Liquid steel temperature is excessively high, and gas is in steel
Solubility with regard to excessive, to steel quality harm influence it is also bigger, the present invention controls the temperature of molten steel.
Cast temperature≤1580 DEG C in step S5.The present invention reduce cast temperature in order to control tissue after solidification in steel,
The appearance for reducing adverse tissue, can be improved the quality of steel ingot.
The present invention has carried out the adjustment of parameter in steel ingot preparation process, and molten steel casting process is maintained at vacuum (vacuum degree
Less than 30Pa) under the conditions of carry out, effectively prevent hydrogenation and nitrogen pick-up of the molten steel in steel pouring process；Molten steel of the present invention is being poured
It is whole in the process to use argon for protecting pouring, contact of the molten steel again with air is prevented, secondary oxidation and air-breathing occurs, fully ensures that
The degree of purity and ultra low gas content of molten steel；The present invention controls ladle refining, vacuum refining time, can be improved steel ingot
Mechanical performance so that steel ingot process pump head body intensity height, corrosion resistance, impact resistance, be suitable for oil exploitation；The present invention
Obtained steel ingot ingot body is fine and close, ingredient is uniform, internal soundness is good.The present invention has carried out constituent analysis to raw material first, according to
The analysis result of raw material adjusts the proportion of each component, so that the quality for the steel ingot produced meets the needs of oil exploitation.
Embodiment 4
Based on the above embodiment, according to chemical component described in embodiment 2 than, with preparation side described in embodiment 3
Method prepares steel ingot, and the steel ingot prepared is processed into pump head body, and the present embodiment has carried out service life, resistance to the pump head body
The test such as Compressive Strength, corrosion-resistant, low-temperature impact, wear rate, test result are as follows: pump head body service life is greater than 1 year；Resistance to pressure
Degree is up to 1400-1600mpa；Low-temperature impact breaks through -40 DEG C of AKV >=34J；The sulfuric acid that mass concentration using boiling is 10% is made
Be corrosion corrosion 48 hours after coating corrosion with a thickness of 0.01-0.02mm；Continue high-speed rotation 24 hours, wear rate is
0.005-0.01%.
Above-described specific embodiment has carried out further the purpose of the present invention, technical scheme and beneficial effects
It is described in detail, it should be understood that being not intended to limit the present invention the foregoing is merely a specific embodiment of the invention
Protection scope, all within the spirits and principles of the present invention, any modification, equivalent substitution, improvement and etc. done should all include
Within protection scope of the present invention.
Claims (6)
1. being used for the nonmagnetic steel ingot of pump head body, which is characterized in that the chemical component including following weight percent: 0.45%-
0.60%C, 0.30-0.80%Si, 17%-19%Mn, 3.5%-6.0%Cr, < 0.30%Ni, < 0.20%Cu, <
0.015%P, < 0.005%S, < 0.10%Mo, 0.015%-0.030%Nb, < 0.010%Sn, 0.1%-0.2%V,
0.010%-0.025%Al, < 0.010%As, < 1.7ppmH, < 25ppmO, < 70ppmN.
2. the nonmagnetic steel ingot according to claim 1 for pump head body, which is characterized in that including following weight percent
Chemical component: 0.45%-0.55%C, 0.30-0.60%Si, 17%-19%Mn, 3.5%-4.0%Cr, < 0.10%Ni,
< 0.20%Cu, < 0.010%P, < 0.005%S, < 0.10%Mo, 0.015%-0.025%Nb, < 0.010%Sn,
0.1%-0.2%V, 0.010%-0.025%Al, < 0.010%As, < 1.7ppmH, < 25ppmO, < 70ppmN.
3. the manufacturing method of the nonmagnetic steel ingot according to claim 1 or 2 for pump head body, which is characterized in that including
Following steps:
S1, electric arc furnace smelting: obtaining raw material and the detection of chemical component is carried out to raw material, makees furnace lining with basic refractory, into
Row is smelted, and the proportion of ingredient in molten steel is adjusted；
S2, tapping: red packet tapping is carried out with the ladle of magnesium refractory preparation；
S3, ladle refining: ladle refining furnace carries out liquid steel refining using white slag, realizes molten steel desulfurizing, deoxidation, white slag refining time
Greater than 30 minutes, alloy was sufficiently added in deoxidization desulfuration afterwards；Molten steel sulfur content is less than 0.003% when ladle refining furnace tapping deoxidization；
S4, vacuum refining: it is kept for 15 minutes or more under vacuum condition of the vacuum degree less than 30Pa, soft blow 15 divides after vacuum
It is more than clock；
S5, argon gas protective casting: molten steel by ladle take off into ingot mould to get to steel ingot.
4. the manufacturing method of the nonmagnetic steel ingot according to claim 3 for pump head body, which is characterized in that in electric arc furnaces
In smelting and ladle refining process, liquid steel temperature≤1660 DEG C.
5. the manufacturing method of the nonmagnetic steel ingot according to claim 3 for pump head body, which is characterized in that in step S5
Cast temperature≤1580 DEG C.
6. the manufacturing method of the nonmagnetic steel ingot according to claim 3 for pump head body, which is characterized in that further include with
Lower step:
S6, steel ingot detection: chemical component detection, white point detection, metallographic detection, ultrasonic flaw detection inspection side are carried out to steel ingot；
S7, steel ingot screening: screened according to the following conditions to steel ingot according to steel ingot testing result: nonmetallic individual event is mingled in steel
Object is less than or equal to 1 grade, and oxide and Sulfide inclusion summation are less than or equal to 2 grades, and pattern segregation, center porosity are less than or equal to 1
Grade, is not allow for general spot segregation and edge spot segregation exists.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910059673.7A CN109797337A (en) | 2019-01-22 | 2019-01-22 | Nonmagnetic steel ingot and its manufacturing method for pump head body |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910059673.7A CN109797337A (en) | 2019-01-22 | 2019-01-22 | Nonmagnetic steel ingot and its manufacturing method for pump head body |
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| Publication Number | Publication Date |
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| CN109797337A true CN109797337A (en) | 2019-05-24 |
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ID=66560066
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910059673.7A Pending CN109797337A (en) | 2019-01-22 | 2019-01-22 | Nonmagnetic steel ingot and its manufacturing method for pump head body |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114280145A (en) * | 2021-12-03 | 2022-04-05 | 南京迪威尔高端制造股份有限公司 | Ultrasonic detection method for steel ingot |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0687745A1 (en) * | 1993-03-25 | 1995-12-20 | Armco Inc. | High strength austenitic stainless steel having excellent galling resistance |
| CN102002647A (en) * | 2010-12-31 | 2011-04-06 | 上海加宁新技术研究所 | High-strength non-magnetic stainless steel |
| CN105839022A (en) * | 2016-03-31 | 2016-08-10 | 宝钢不锈钢有限公司 | High-hardness non-magnetic nickelless stainless steel and manufacturing method thereof |
| CN106086598A (en) * | 2016-08-23 | 2016-11-09 | 四川丰元机械制造有限公司 | A kind of high cleanliness austenite is without the smelting process of magnetic Retaining Ring Steel |
-
2019
- 2019-01-22 CN CN201910059673.7A patent/CN109797337A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0687745A1 (en) * | 1993-03-25 | 1995-12-20 | Armco Inc. | High strength austenitic stainless steel having excellent galling resistance |
| CN102002647A (en) * | 2010-12-31 | 2011-04-06 | 上海加宁新技术研究所 | High-strength non-magnetic stainless steel |
| CN105839022A (en) * | 2016-03-31 | 2016-08-10 | 宝钢不锈钢有限公司 | High-hardness non-magnetic nickelless stainless steel and manufacturing method thereof |
| CN106086598A (en) * | 2016-08-23 | 2016-11-09 | 四川丰元机械制造有限公司 | A kind of high cleanliness austenite is without the smelting process of magnetic Retaining Ring Steel |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114280145A (en) * | 2021-12-03 | 2022-04-05 | 南京迪威尔高端制造股份有限公司 | Ultrasonic detection method for steel ingot |
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