CN111304514B - Manufacturing process of high-pressure hydrogen carbon steel valve casting - Google Patents
Manufacturing process of high-pressure hydrogen carbon steel valve casting Download PDFInfo
- Publication number
- CN111304514B CN111304514B CN201911230041.9A CN201911230041A CN111304514B CN 111304514 B CN111304514 B CN 111304514B CN 201911230041 A CN201911230041 A CN 201911230041A CN 111304514 B CN111304514 B CN 111304514B
- Authority
- CN
- China
- Prior art keywords
- resistor
- operational amplifier
- furnace
- molten steel
- controller
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/06—Deoxidising, e.g. killing
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/064—Dephosphorising; Desulfurising
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/064—Dephosphorising; Desulfurising
- C21C7/0645—Agents used for dephosphorising or desulfurising
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/10—Handling in a vacuum
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/18—Hardening; Quenching with or without subsequent tempering
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/26—Methods of annealing
- C21D1/28—Normalising
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D23/00—Control of temperature
- G05D23/19—Control of temperature characterised by the use of electric means
- G05D23/20—Control of temperature characterised by the use of electric means with sensing elements having variation of electric or magnetic properties with change of temperature
Abstract
The invention provides a manufacturing process of a high-pressure hydrogen carbon steel valve casting, which comprises the following steps of: step S1: production preparation, step S2: a smelting step comprising: rough smelting and fine smelting, wherein dephosphorization is carried out in the rough smelting, and desulfurization, degassing and secondary deoxidation are carried out in the fine smelting; step S2 is followed by: step S3: adjusting chemical components; step S4: removing impurities; step S5: controlling the temperature for pouring; step S6: opening the box and cleaning sand; step S7: a first heat treatment including a normalizing treatment and a first tempering treatment; step S8: detecting chemical components and testing; step S9: first lossless detection; step S10: and (4) defect cleaning and defect repair welding, and performing second heat treatment and second nondestructive testing in sequence after repair welding. The invention can improve the quality of the casting.
Description
Technical Field
The invention relates to the technical field of casting manufacturing processes, in particular to a manufacturing process of a high-pressure hydrogen carbon steel valve casting.
Background
The high-temperature high-pressure hydrogen valve is an important pipeline element of a hydrogenation system device in petrochemical industry production, the working condition pressure grade of the high-temperature high-pressure hydrogen valve is more than ANSICL900, the medium temperature is 0-500 ℃, hydrogen parts of various series of carbon steel valves on the device are complex in shape, most of the high-temperature high-pressure hydrogen valve is a steel casting, and the medium for storing and transporting the high-pressure hydrogen valve (including a pipeline) is inflammable and explosive high-pressure gas (hydrogen or oil gas and hydrogen). If the valve is damaged, serious accidents are caused. Therefore, strict requirements are imposed on the material, structural design, strength design, manufacturing weight, and the like of the valve. The existing high-pressure hydrogen carbon steel valve casting has poor casting quality due to high content of harmful elements, more impurities and insufficient deoxidation.
Disclosure of Invention
The invention provides a manufacturing process of a high-pressure hydrogen carbon steel valve casting, which is used for solving at least one of the technical problems.
A manufacturing process of a high-pressure hydrogen carbon steel valve casting comprises the following steps: step S1: production preparation, step S2: a smelting step, the smelting step comprising: the method comprises the following steps of (1) rough smelting and fine smelting, wherein dephosphorization treatment is carried out in the rough smelting, and desulfurization treatment, degassing treatment and secondary deoxidation treatment are carried out in the fine smelting;
the step S2 is followed by:
step S3: adjusting chemical components;
step S4: removing impurities;
step S5: controlling the temperature for pouring;
step S6: opening the box and cleaning sand;
step S7: a first heat treatment including a normalizing treatment and a first tempering treatment;
step S8: detecting chemical components and testing;
step S9: first lossless detection;
step S10: and (4) defect cleaning and defect repair welding, and performing second heat treatment and second nondestructive testing in sequence after repair welding.
Preferably, the defect cleaning includes: step S101: removing the defects detected by the first nondestructive testing through carbon arc gouging and polishing;
the second heat treatment comprises: and (5) performing second tempering treatment.
Preferably, the first and second nondestructive tests are any one or more combinations of MT, PT, VT and RT tests.
Preferably, the rough smelting is rough smelting in an intermediate frequency furnace, and comprises the following steps: sampling and analyzing the steel raw material for one time after the steel raw material is completely melted, blowing oxygen and dephosphorizing to the phosphorus content of below 0.005% according to the sampling result for one time when the temperature is 1530-1540 ℃, then sampling and analyzing again, and tapping when the temperature of the molten steel is raised to 1620-1640 ℃;
the fine smelting comprises the following steps: step S21 and step S22;
the step S21: fine smelting through an LF furnace mechanism: heating the molten steel to 1590-1600 ℃, and adding a desulfurizing agent to desulfurize the molten steel until the sulfur content is below 0.005%;
blowing oxygen for decarburization to reduce the content of C in the molten steel to below 0.2 percent;
when the temperature of the molten steel is more than or equal to 1610 ℃, adding rare earth calcium-silicon alloy accounting for 1.0 percent of the weight of the molten steel for primary deoxidation, and stirring simultaneously;
after the metal is molten, uniformly adding rare earth silicon calcium alloy powder accounting for 0.16-0.18 percent of the weight of the molten steel for secondary deoxidation, and adding lime powder and fluorite powder;
the step S22: VOD furnace vacuum degassing.
Preferably, component detection is performed before the molten steel melted in the step S21 is discharged from the furnace;
step S3 is to adjust the components by the LF furnace: adjusting the content of chemical elements according to the result of the component detection in the step S21, wherein the control C of key elements of the carbon steel casting is 0.19-0.20%, the carbon equivalent CE is C + Mn/6+ (Cr + Mo + V)/5+ (Ni + Cu)/15 is less than or equal to 0.4%, and the S is less than or equal to 0.005%; p is less than or equal to 0.005 percent; pb is less than or equal to 0.020%; as is less than or equal to 0.020%; se is less than or equal to 0.020%; n is less than or equal to 0.015 percent, and other chemical elements are executed according to the ASTM standard requirement of the corresponding grade.
Preferably, the rare earth silicon calcium alloy comprises the following components: rare earth: 20-22%, Ca: 12-18%, Ba: 8-12%, Ti: 10-15%, Zr: 8-18%, Si: 12-18%, Mg: 1-2% and the balance of Fe.
Preferably, the step S4 includes: adding calcium or rare earth silicon-calcium alloy to spheroidize the nonmetallic inclusion;
adding a molten steel impurity removing agent for removing impurities, wherein the molten steel impurity removing agent comprises the following components: 10-13% of magnesium carbonate, silicon carbide: 12-14%, sodium hydroxide: 5-7%, calcium carbide 7-9%, calcium oxide 50-55%, rare earth: 0.1 to 0.15 percent.
Preferably, the LF furnace mechanism includes:
the furnace body is provided with a temperature sensor;
the furnace body is arranged at the top end of the fixed seat, and a weight sensor is arranged at the position on the fixed seat where the furnace body is arranged;
the furnace cover is used for sealing or opening the top end opening of the furnace body;
the furnace cover opening and molten steel stirring device is connected with the furnace cover and is used for controlling the furnace cover to seal or open the top end opening of the furnace body and stirring the molten steel in the furnace body;
the sampling device is connected with the furnace cover and is used for sampling and detecting molten steel in the furnace body;
the oxygen blowing device is connected with the furnace cover and is used for blowing oxygen into the furnace body for decarburization;
the heating device is connected with the furnace body or the furnace cover;
and the controller is positioned outside the furnace body and is respectively and electrically connected with the temperature sensor, the heating device, the oxygen blowing device, the sampling device, the stirring device and the weight sensor.
Preferably, the furnace cover opening and molten steel stirring device comprises:
the support is fixedly connected to the top end of the fixed seat and positioned on one side of the furnace body, and comprises a vertical support and a horizontal support fixedly connected to one side, close to the furnace body, of the vertical support;
the rotating motor is arranged at the bottom end of the horizontal bracket, and an output shaft of the rotating motor is arranged downwards vertically;
the upper part of the fixed end of the electric telescopic rod is rotatably connected with the horizontal bracket through a first bearing;
the first gear is fixedly sleeved on the output shaft of the rotating motor;
the second gear is fixedly sleeved on the lower part of the fixed end of the electric telescopic rod;
the upper end of the hollow vertical connecting rod is fixedly connected with the telescopic end at the lower end of the electric telescopic rod, and the upper part of the hollow vertical connecting rod is rotatably connected with the upper end of the furnace cover through a second bearing;
the hollow blades are arranged at the lower part of the hollow vertical connecting rod at intervals, the hollow blades are communicated with the hollow vertical connecting rod, and vent holes are formed in the hollow blades;
a sampling pipe of a sampling detection device is connected to the furnace cover;
the furnace cover is connected with an exhaust pipe for connecting with a waste gas treatment device;
the oxygen blowing device comprises: the first pipeline is fixedly connected with the upper part of the hollow vertical connecting rod, the first pipeline is connected with a first end of a three-way joint, a second end of the three-way joint is connected with an oxygen source through a second pipeline, a third end of the three-way joint is connected with an argon source through a third pipeline, and the second pipeline and the third pipeline are both provided with electromagnetic valves;
the rotating motor, the electric telescopic rod and the electromagnetic valve are all electrically connected with the controller.
Preferably, the controller is connected to an oxygen blowing driving circuit through a timing circuit, the oxygen blowing driving circuit is connected to the oxygen blowing device, and the timing circuit includes:
one end of the fourth resistor is connected with the controller;
the inverting input end of the third operational amplifier is grounded through the first resistor, and the non-inverting input end of the third operational amplifier is connected with the other end of the fourth resistor;
one end of the fifth resistor is connected with the non-inverting input end of the third operational amplifier, the other end of the fifth resistor is connected with the first end of the sixth resistor, the second end of the sixth resistor is grounded, and the first end of the sixth resistor is also connected with the output end of the third operational amplifier;
one end of the eighth resistor is connected with the output end of the third operational amplifier;
the base electrode of the first transistor is connected with the other end of the eighth resistor;
one end of the ninth resistor is connected with the collector of the first transistor, and the other end of the ninth resistor is connected with the output end of the third operational amplifier;
one end of the seventh resistor is connected with the base electrode of the first transistor, and the other end of the seventh resistor is connected with the emitting electrode of the first transistor and grounded;
one end of the third capacitor is connected with the collector of the first transistor, and the other end of the third capacitor is connected with the emitter of the first transistor;
the non-inverting input end of the fourth operational amplifier is connected with the collector electrode of the first transistor, and the inverting input end of the fourth operational amplifier is connected with the power supply through an eleventh resistor;
one end of the tenth resistor is connected with the inverting input end of the fourth operational amplifier, and the other end of the tenth resistor is grounded;
the controller still is connected with overvoltage crowbar, overvoltage crowbar includes:
a first end of the adjustable shunt reference source is connected with the power supply voltage of the controller, a second end of the adjustable shunt reference source is connected with one end of the second capacitor, and a third end of the adjustable shunt reference source is connected with one end of the fourteenth resistor;
the non-inverting input end of the second operational amplifier is connected with the other end of the fourteenth resistor, and the inverting input end of the second operational amplifier is connected with the power supply voltage of the controller through the twelfth resistor;
one end of the thirteenth resistor is connected with the inverting input end of the second operational amplifier, and the other end of the thirteenth resistor is connected with the output end of the second operational amplifier;
the inverting input end of the first operational amplifier is connected with the output end of the second operational amplifier, and the non-inverting input end of the first operational amplifier is connected with the other end of the second capacitor;
the base of the second crystal triode is connected with the output end of the first operational amplifier, and the emitter of the second crystal triode is connected with the power supply voltage of the controller;
one end of the first capacitor is connected with the in-phase input end of the first transistor, and the other end of the first capacitor is connected with the controller;
one end of the second resistor is connected with the collector of the second transistor, and the other end of the second resistor is connected with the controller;
and the anode of the photoelectric coupler is connected with the collector of the second crystal triode, the cathode of the photoelectric coupler is connected with the power supply voltage of the controller, the emitter of the photoelectric coupler is connected with the power supply voltage of the controller through a third resistor, and the collector of the photoelectric coupler is connected with the controller.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and drawings.
The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:
FIG. 1 is a process flow diagram of the present invention.
FIG. 2 is a schematic view showing the structure of the apparatus for stirring molten steel with opening the cover according to the present invention.
Fig. 3 is a circuit diagram of a timing circuit and an overvoltage protection circuit of the present invention.
In the figure: 1. a furnace body; 2. a furnace cover; 21. a second bearing; 3. a fixed seat; 4. opening a furnace cover and a molten steel stirring device; 41. a support; 411. a vertical support; 412. a horizontal support; 413. a first bearing; 42. a rotating electric machine; 43. a first gear; 44. a second gear; 45. a hollow vertical connecting rod; 46. a hollow blade; 461. a vent hole; 47. a sampling tube of the sampling detection device; 48. an exhaust pipe; 49. an electric telescopic rod; 5. a first conduit; r1, a first resistor; r2, a second resistor; r3, third resistor; r4, fourth resistor; r5, fifth resistor; r6, sixth resistor; r7, seventh resistor; r8, eighth resistor; r9, ninth resistor; r10, tenth resistor; r11, eleventh resistor; r12, twelfth resistor; r13, thirteenth resistor; r14, fourteenth resistance; c1, a first capacitance; c2, a second capacitor; c3, a third capacitance; q1, the first transistor; q2, second transistor; u1, a first operational amplifier; u2, a second operational amplifier; u3, third operational amplifier; u4, fourth operational amplifier; u5, a photoelectric isolator; u6, an adjustable shunt reference source; v1, controller supply voltage.
Detailed Description
The preferred embodiments of the present invention will be described in conjunction with the accompanying drawings, and it will be understood that they are described herein for the purpose of illustration and explanation and not limitation.
In addition, the descriptions related to the first, the second, etc. in the present invention are only used for description purposes, do not particularly refer to an order or sequence, and do not limit the present invention, but only distinguish components or operations described in the same technical terms, and are not understood to indicate or imply relative importance or implicitly indicate the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, technical solutions and technical features between various embodiments can be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not be within the protection scope of the present invention.
The embodiment of the invention provides a manufacturing process of a high-pressure hydrogen carbon steel valve casting, which comprises the following steps of:
step S1: preparing for production, including; selecting a steel raw material (such as a low-sulfur, low-phosphorus, clean, rust-free and bright steel raw material, preferably 08F or 10F scrap steel, also can be selected), adding metal elements (preferably, pure metal is selected to avoid more inclusions), sand molds (CO 2 water glass quartz sand molds are adopted), and other related auxiliary materials;
step S2: a smelting step, the smelting step comprising: the method comprises the following steps of (1) rough smelting and fine smelting, wherein dephosphorization treatment is carried out in the rough smelting, and desulfurization treatment, degassing treatment and secondary deoxidation treatment are carried out in the fine smelting;
preferably, the rough smelting is rough smelting in an intermediate frequency furnace, and comprises the following steps: carrying out sampling analysis for one time after the steel raw material is completely melted, carrying out oxygen blowing dephosphorization according to a sampling result until the phosphorus content is below 0.005% (in percentage by weight of the molten steel) when the temperature is 1530-1540 ℃, then carrying out sampling analysis again, and tapping when the temperature of the molten steel is raised to 1620-1640 ℃; the rough smelting is used for dephosphorization, so that the fine smelting time is saved, and the quality of molten steel is improved;
the fine smelting comprises the following steps: step S21 and step S22;
step S21: fine smelting through an LF furnace mechanism: heating the molten steel to 1590-1600 ℃, and adding a desulfurizing agent to desulfurize the molten steel until the sulfur content is below 0.005% (in percentage by weight of the molten steel);
blowing oxygen for decarburization to reduce the content of C in the molten steel to below 0.2 percent;
when the temperature of the molten steel is more than or equal to 1610 ℃, adding rare earth calcium-silicon alloy accounting for 1.0 percent of the weight of the molten steel for primary deoxidation, and stirring simultaneously;
after the metal is molten, uniformly adding rare earth silicon calcium alloy powder accounting for 0.16-0.18 percent of the weight of the molten steel for secondary deoxidation, and adding lime powder and fluorite powder for adjusting the viscosity of the slag to ensure that the slag has good fluidity; preferably, the rare earth silicon calcium alloy (powder) comprises the following components: rare earth: 20-22%, Ca: 12-18%, Ba: 8-12%, Ti: 10-15%, Zr: 8-18%, Si: 12-18%, Mg: 1-2% and the balance of Fe.
The rare earth calcium-silicon alloy is added for oxidation in the secondary oxidation, the rare earth calcium-silicon alloy has the advantage of good oxidation effect, secondary oxidation is carried out step by step and stirring is carried out, the oxidation effect can be improved, sufficient oxidation is carried out, and the quality of molten steel is improved.
Detecting components of the molten steel smelted in the step S21 before tapping (facilitating adjustment of components after vacuum degassing);
step S22: VOD furnace vacuum degassing.
Step S3: adjusting chemical components; the step S3 is to adjust the composition by the LF oven (the LF oven mechanism of step S2 may be adopted): adjusting the chemical element content according to the result of the component detection of step S21;
the carbon steel casting has the key elements of C0.19-0.20%, C + Mn/6+ (Cr + Mo + V)/5+ (Ni + Cu)/15% and S not more than 0.4%; p is less than or equal to 0.005 percent; pb is less than or equal to 0.020%; as is less than or equal to 0.020%; se is less than or equal to 0.020%; n is less than or equal to 0.015 percent, and other chemical elements are executed according to the ASTM standard requirement of the corresponding grade.
Step S4: removing impurities; preferably, the step S4 includes: adding calcium or rare earth silicon-calcium alloy to spheroidize the nonmetallic inclusion; the molten steel impurity removing agent comprises the following components: 10-13% of magnesium carbonate, silicon carbide: 12-14%, sodium hydroxide: 5-7%, calcium carbide 7-9%, calcium oxide 50-55%, rare earth: 0.1 to 0.15 percent. Calcium or rare earth silicon-calcium alloy is added to spheroidize the nonmetallic inclusion, so that the removal effect is good, and the spheroidization is convenient to clean; the molten steel impurity removing agent has good impurity removing effect.
Step S5: controlling the temperature for pouring (preferably, the VOD furnace tapping temperature is 1590-;
step S6: opening the box and cleaning sand (the opening temperature is the surface temperature of the thickest part of the casting is less than 200 ℃);
step S7: the first heat treatment comprises normalizing treatment and first tempering treatment (the temperature rise speed is less than or equal to 110 ℃/h during normalizing, the heat preservation temperature is 940 ℃, the heat preservation time is more than 5h, and the slow air cooling is 110 ℃/h; the temperature rise speed is less than or equal to 110 ℃/h during tempering, the heat preservation temperature is 670 ℃, the heat preservation time is more than 5h, and the slow air cooling is less than or equal to 110 ℃/h);
step S8: detecting chemical components and tests (the tests comprise metallographic structure and etching tests and mechanical property tests);
step S9: first lossless detection;
step S10: and (4) defect cleaning and defect repair welding (repair welding is carried out only when the defects can be repaired), and after repair welding, second heat treatment and second nondestructive testing are carried out in sequence. The defect cleaning includes: step S101: removing the defects detected by the first nondestructive testing through carbon arc gouging and polishing; grinding to be smooth and transitional after welding repair, and avoiding scratches and local burns; the second heat treatment comprises: and (5) performing second tempering treatment. Clear away through the cleaing away that first nondestructive test detected out through carbon arc gouging and polishing, can clear away clean defect, avoid influencing follow-up repair welding, carry out once more thermal treatment after the repair welding and improve the steel quality, and carry out nondestructive test once more and guarantee the steel quality.
The first nondestructive test and the second nondestructive test are any one or a combination of MT (magnetic powder), PT (penetration), VT (macroscopic) and RT (ray) tests.
The working principle and the beneficial effects of the technical scheme are as follows: the invention realizes full control and reduction of harmful elements (phosphorus and sulfur) on the carbon steel casting by dephosphorization treatment during rough smelting and desulfurization treatment during fine smelting of the LF furnace mechanism, and realizes full deoxidation, pore removal and impurity removal (slag inclusion and non-metallic inclusion) through vacuum degassing and secondary deoxidation and impurity removal steps, thereby improving the casting quality.
In one embodiment, as shown in fig. 2, the LF furnace mechanism includes:
the furnace comprises a furnace body 1, wherein a temperature sensor is arranged on the furnace body 1;
the furnace body 1 is arranged at the top end of the fixed seat 3, and a weight sensor is arranged at the position, where the furnace body 1 is arranged, on the fixed seat 3;
the furnace cover 2 is used for sealing or opening the top end opening of the furnace body 1;
the furnace cover opening and molten steel stirring device 4 is connected with the furnace cover 2 and is used for controlling the furnace cover 2 to seal or open the top opening of the furnace body 1 and stirring molten steel in the furnace body 1;
the sampling device is connected with the furnace cover 2 and is used for sampling and detecting molten steel in the furnace body 1;
the oxygen blowing device is connected with the furnace cover 2 and is used for blowing oxygen into the furnace body 1 for decarburization;
the heating device is connected with the furnace body 1 or the furnace cover 2;
the controller is located outside the furnace body 1, and the controller respectively with temperature sensor, heating device (adopt the heating device of current LF stove), oxygen blast device, sampling device (oxygen blast device and sampling device can refer to now), agitating unit, weighing sensor electricity are connected. Preferably, the controller can be arranged on the following vertical support, and further comprises a touch display screen electrically connected with the controller, and control parameters, such as heating temperature and other parameters, can be set in the touch display screen, and are convenient to observe.
The working principle and the beneficial effects of the technical scheme are as follows: the weight sensor is used for detecting furnace body weight value information and transmitting the furnace body weight value information to the controller, and the controller displays the information through the touch control type display screen, so that an operator can add related additives, such as rare earth calcium oxide alloy and other substances needing to be added in the smelting process, the weight can be monitored in real time, accurate control is facilitated, and the casting quality is improved;
the temperature sensor is used for detecting the temperature value information of the molten steel in the furnace body and transmitting the temperature value information to the controller, the controller displays the temperature information through the touch control type display screen, so that the temperature can be conveniently controlled (preferably, an alarm can be arranged to prompt when the temperature reaches a specified temperature), and if the temperature information corresponds to the temperature, the rare earth calcium alloy is added, so that the accurate control is convenient, and the quality of a casting is improved;
a furnace cover opening and molten steel stirring device 4 is arranged, is connected with the furnace cover 2 and is used for controlling the furnace cover 2 to seal or open the top opening of the furnace body 1 and stirring the molten steel in the furnace body 1; the furnace cover is convenient to open and stir, so that molten steel is uniform, and the quality of castings is improved.
The working principle and the beneficial effects of the technical scheme are as follows:
as shown in fig. 2, in one embodiment, the furnace cover opening and molten steel stirring apparatus 4 includes:
the support 41 is fixedly connected to the top end of the fixed seat 3 and is positioned on one side of the furnace body 1, and the support 41 comprises a vertical support 411 and a horizontal support 412 fixedly connected to one side, close to the furnace body 1, of the vertical support 411;
the rotating motor 42 is arranged at the bottom end of the horizontal bracket 412, and an output shaft of the rotating motor 42 is arranged vertically downwards;
the upper part of the fixed end of the electric telescopic rod 49 is rotatably connected with the horizontal support 412 through a first bearing 413 (for example, a vertical through hole is formed in the horizontal support, the first bearing is fixedly sleeved in the vertical through hole, the outer ring of the first bearing is fixedly sleeved with the outer wall of the vertical through hole, and the inner ring of the first bearing is fixedly sleeved with the fixed end of the electric telescopic rod);
a first gear 43 fixedly secured to an output shaft of the rotary motor 42;
a second gear 44 fixedly sleeved on the lower part of the fixed end of the electric telescopic rod 49;
the upper end of the hollow vertical connecting rod 45 is fixedly connected with the telescopic end at the lower end of the electric telescopic rod 49, and the upper part of the hollow vertical connecting rod 45 is rotatably connected with the upper end of the furnace cover 2 through a second bearing 21;
the hollow blades 46 are arranged at the lower part 45 of the hollow vertical connecting rod at intervals, the hollow blades 46 are communicated with the hollow vertical connecting rod 45, and the hollow blades 46 are provided with vent holes 461;
a sampling pipe 47 of a sampling detection device (which can adopt the existing sampling detection device) is connected to the furnace cover 2;
an exhaust pipe 48 is connected to the furnace cover 2 and is used for connecting an exhaust gas treatment device, and preferably, the exhaust gas treatment device is electrically connected with a controller;
the oxygen blowing device comprises: the first pipeline 5 is fixedly connected with the upper part of the hollow vertical connecting rod 45, the first pipeline 5 is connected with a first end of a three-way joint, a second end of the three-way joint is connected with an oxygen source through a second pipeline, a third end of the three-way joint is connected with an argon source through a third pipeline, and electromagnetic valves (used for controlling the opening and closing of the pipelines and adjusting the gas flow rate) are arranged on the second pipeline and the third pipeline;
the rotating motor 42, the electric telescopic rod 49 and the electromagnetic valve are all electrically connected with the controller.
The working principle of the technical scheme is as follows: after corresponding additive substances are added in the smelting process, the controller can control the electric telescopic rod to extend to seal the opening at the top end of the furnace body, meanwhile, the hollow vertical connecting rod and the hollow blade enter the furnace body to be stirred, then the rotating motor is controlled to rotate to stir, so that molten steel is uniform and the reaction is accelerated, and the reaction is sufficient;
when oxygen blowing is needed, the electromagnetic valve on the second pipeline is opened to blow oxygen for decarburization in the furnace body, when argon is needed to be introduced for preliminary degassing, the electromagnetic valve on the third pipeline is opened to blow argon for degassing in the furnace body (preliminary degassing can be carried out, and then sufficient degassing is realized through the vacuum degassing), and meanwhile, the rotation of the rotating motor is controlled, so that the decarburization and the degassing can be accelerated, and the working efficiency is improved;
and in the smelting process, opening the waste gas treatment device for discharging and treating waste gas.
The beneficial effects of the above technical scheme are: the furnace cover opening and molten steel stirring device integrates the furnace cover opening and closing function and the molten steel stirring function, simplifies the structure, can be realized by controlling the electric telescopic rod and the rotating motor, is convenient to control, is convenient to open the furnace cover, can realize the acceleration reaction and the full reaction by stirring in the smelting process, and improves the working efficiency and the casting quality; the furnace cover is connected with the stirring component, the exhaust pipe and the sampling pipe of the sampling detection device, so that the structure of the furnace body is simplified, and the difficulty in opening the furnace cover is avoided;
and will stir the structure and blow the oxygen decarbonization and blow the argon gas degasification function integration, simplified whole device structure, and be convenient for control and blow the oxygen decarbonization and blow the argon gas degasification for blow the oxygen decarbonization and blow the argon gas degasification and fully blow the oxygen decarbonization and blow the argon gas degasification, improve work efficiency and foundry goods quality.
In one embodiment, as shown in fig. 3, the controller is connected to an oxygen blowing driving circuit through a timing circuit, the oxygen blowing driving circuit is connected to an oxygen blowing device, and the timing circuit comprises:
one end of the fourth resistor R4 is connected with the controller;
the inverting input end of the third operational amplifier U3 is grounded through the first resistor R1, and the non-inverting input end of the third operational amplifier U3 is connected with the other end of the fourth resistor R4;
a fifth resistor R5 and a sixth resistor R6, wherein one end of the fifth resistor R5 is connected with the non-inverting input end of the third operational amplifier U3, the other end of the fifth resistor R3526 is connected with the first end of the sixth resistor R6, the second end of the sixth resistor R6 is grounded, and the first end of the sixth resistor R6 is also connected with the output end of the third operational amplifier U3;
an eighth resistor R8, one end of which is connected to the output end of the third operational amplifier U3;
a base electrode of the first transistor Q1 is connected with the other end of the eighth resistor R8;
a ninth resistor R9, one end of which is connected with the collector of the first transistor Q1 and the other end of which is connected with the output end of the third operational amplifier U3;
one end of the seventh resistor R7 is connected with the base electrode of the first transistor Q1, and the other end of the seventh resistor R7 is connected with the emitter electrode of the first transistor Q1 and is grounded;
a third capacitor C3 (an electrolytic capacitor) having one end connected to the collector of the first transistor Q1 and the other end connected to the emitter of the first transistor Q1;
a non-inverting input terminal of the fourth operational amplifier U4 is connected to the collector of the first transistor Q1, and an inverting input terminal of the fourth operational amplifier U4 is connected to the power supply through an eleventh resistor R11;
a tenth resistor R10, one end of which is connected to the inverting input terminal of the fourth operational amplifier U4 and the other end of which is grounded;
the controller still is connected with overvoltage crowbar, overvoltage crowbar includes:
the first end of the adjustable shunt reference source U6 is connected with the power supply voltage V1 of the controller, the second end of the adjustable shunt reference source U6 is connected with one end of the second capacitor C2, and the third end of the adjustable shunt reference source U6 is connected with one end of the fourteenth resistor R14;
the non-inverting input end of the second operational amplifier U2 is connected with the other end of the fourteenth resistor R14, and the inverting input end of the second operational amplifier U2 is connected with the power supply voltage of the controller through a twelfth resistor R12;
a thirteenth resistor R13, one end of which is connected to the inverting input terminal of the second operational amplifier U2, and the other end of which is connected to the output terminal of the second operational amplifier U2;
the inverting input end of the first operational amplifier U1 is connected with the output end of the second operational amplifier U2, and the non-inverting input end of the first operational amplifier U1 is connected with the other end of the second capacitor C2;
a base electrode of the second transistor Q2 is connected with the output end of the first operational amplifier U1, and an emitter electrode of the second transistor Q2 is connected with the power supply voltage V1 of the controller;
one end of the first capacitor C1 is connected with the non-inverting input end of the first transistor Q1, and the other end of the first capacitor C1 is connected with the controller;
one end of the second resistor R2 is connected with the collector of the second transistor Q2, and the other end is connected with the controller;
and the anode of the photoelectric coupler is connected with the collector of a second transistor triode Q2, the cathode of the photoelectric coupler is connected with the controller power voltage V1, the emitter of the photoelectric coupler is connected with the controller power voltage V1 through a third resistor R3, and the collector of the photoelectric coupler is connected with the controller.
The working principle and the beneficial effects of the technical scheme are as follows: the overvoltage protection circuit ensures that the power voltage V1 of the controller is constant, the controller is amplified by a preset multiple and then outputs a voltage reference value with the size equal to a high-voltage threshold value, the power voltage V1 of the controller is compared with the voltage reference value, an overvoltage protection signal is output when the power voltage V1 of the controller is larger than the voltage reference value to control the disconnection of the protection circuit, the voltage output end of a circuit to be protected by the overvoltage protection circuit and a loop formed by the controller are arranged, the damage of overvoltage of the output end to the controller is avoided, the normal work of the controller is ensured, the casting process control is facilitated, and the casting quality is improved.
The timing circuit is simple, and when the set time is reached, the controller controls the oxygen blowing device to stop working, so that the quality of the casting is ensured conveniently.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (8)
1. A manufacturing process of a high-pressure hydrogen carbon steel valve casting comprises the following steps: step S1: production preparation, step S2: a melting step, characterized in that the melting step comprises: the method comprises the following steps of (1) rough smelting and fine smelting, wherein dephosphorization treatment is carried out in the rough smelting, and desulfurization treatment, degassing treatment and secondary deoxidation treatment are carried out in the fine smelting;
the step S2 is followed by:
step S3: adjusting chemical components;
step S4: removing impurities;
step S5: controlling the temperature for pouring;
step S6: opening the box and cleaning sand;
step S7: a first heat treatment including a normalizing treatment and a first tempering treatment;
step S8: detecting chemical components and testing;
step S9: first lossless detection;
step S10: cleaning the defects and welding the defects, and sequentially carrying out second heat treatment and second nondestructive testing after welding;
the rough smelting is rough smelting through an intermediate frequency furnace, and comprises the following steps: sampling and analyzing the steel raw material for one time after the steel raw material is completely melted, blowing oxygen and dephosphorizing to the phosphorus content of below 0.005% according to the sampling result for one time when the temperature is 1530-1540 ℃, then sampling and analyzing again, and tapping when the temperature of the molten steel is raised to 1620-1640 ℃;
the fine smelting comprises the following steps: step S21 and step S22;
the step S21: fine smelting through an LF furnace mechanism: heating the molten steel to 1590-1600 ℃, and adding a desulfurizing agent to desulfurize the molten steel until the sulfur content is below 0.005%;
blowing oxygen for decarburization to reduce the content of C in the molten steel to below 0.2 percent;
when the temperature of the molten steel is more than or equal to 1610 ℃, adding rare earth calcium-silicon alloy accounting for 1.0 percent of the weight of the molten steel for primary deoxidation, and stirring simultaneously;
after the metal is molten, uniformly adding rare earth silicon calcium alloy powder accounting for 0.16-0.18 percent of the weight of the molten steel for secondary deoxidation, and adding lime powder and fluorite powder;
the step S22: vacuum degassing in a VOD furnace;
the rare earth silicon-calcium alloy comprises the following components: rare earth: 20-22%, Ca: 12-18%, Ba: 8-12%, Ti: 10-15%, Zr: 8-18%, Si: 12-18%, Mg: 1-2% and the balance of Fe.
2. The process for manufacturing a high pressure hydrogen carbon steel valve casting according to claim 1,
the defect cleaning includes: step S101: removing the defects detected by the first nondestructive testing through carbon arc gouging and polishing;
the second heat treatment comprises: and (5) performing second tempering treatment.
3. The process for manufacturing a high pressure hydrogen carbon steel valve casting according to claim 1,
the first nondestructive detection and the second nondestructive detection are any one or more combinations of MT, PT, VT and RT detection.
4. The process for manufacturing a high pressure hydrogen carbon steel valve casting according to claim 1,
detecting components of the molten steel smelted in the step S21 before the molten steel is discharged out of the furnace;
step S3 is to adjust the components by the LF furnace: adjusting the content of chemical elements according to the result of the component detection in the step S21, wherein the control C of key elements of the carbon steel casting is 0.19-0.20%, the carbon equivalent CE is C + Mn/6+ (Cr + Mo + V)/5+ (Ni + Cu)/15 is less than or equal to 0.4%, and the S is less than or equal to 0.005%; p is less than or equal to 0.005 percent; pb is less than or equal to 0.020%; as is less than or equal to 0.020%; se is less than or equal to 0.020%; n is less than or equal to 0.015 percent, and other chemical elements are executed according to the ASTM standard requirement of the corresponding grade.
5. The process for manufacturing a high pressure hydrogen carbon steel valve casting according to claim 1,
the step S4 includes: adding calcium or rare earth silicon-calcium alloy to spheroidize the nonmetallic inclusion;
adding a molten steel impurity removing agent for removing impurities, wherein the molten steel impurity removing agent comprises the following components: 10-13% of magnesium carbonate, silicon carbide: 12-14%, sodium hydroxide: 5-7%, calcium carbide 7-9%, calcium oxide 50-55%, rare earth: 0.1 to 0.15 percent.
6. The process of manufacturing a high pressure hydrogen carbon steel valve casting of claim 1, wherein the LF furnace mechanism comprises:
the furnace comprises a furnace body (1), wherein a temperature sensor is arranged on the furnace body (1);
the furnace body (1) is arranged at the top end of the fixed seat (3), and a weight sensor is arranged at the position, where the furnace body (1) is arranged, on the fixed seat (3);
the furnace cover (2) is used for sealing or opening the top end opening of the furnace body (1);
the furnace cover opening and molten steel stirring device (4) is connected with the furnace cover (2) and is used for controlling the furnace cover (2) to seal or open the top end opening of the furnace body (1) and stirring molten steel in the furnace body (1);
the sampling device is connected with the furnace cover (2) and is used for sampling and detecting molten steel in the furnace body (1);
the oxygen blowing device is connected with the furnace cover (2) and is used for blowing oxygen into the furnace body (1) for decarburization;
the heating device is connected with the furnace body (1) or the furnace cover (2);
and the controller is positioned outside the furnace body (1), and is respectively and electrically connected with the temperature sensor, the heating device, the oxygen blowing device, the sampling device, the stirring device and the weight sensor.
7. The process for manufacturing a high pressure hydrogen carbon steel valve casting according to claim 6,
the furnace cover opening and molten steel stirring device (4) comprises:
the support (41) is fixedly connected to the top end of the fixed seat (3) and is positioned on one side of the furnace body (1), and the support (41) comprises a vertical support (411) and a horizontal support (412) which is fixedly connected to one side, close to the furnace body (1), of the vertical support (411);
the rotating motor (42) is arranged at the bottom end of the horizontal support (412), and an output shaft of the rotating motor (42) is arranged downwards vertically;
the electric telescopic rod (49) is vertically arranged, and the upper part of the fixed end of the electric telescopic rod (49) is rotatably connected with the horizontal support (412) through a first bearing (413);
a first gear (43) fixedly sleeved on an output shaft of the rotating motor (42);
the second gear (44) is fixedly sleeved at the lower part of the fixed end of the electric telescopic rod (49);
the upper end of the hollow vertical connecting rod (45) is fixedly connected with the telescopic end at the lower end of the electric telescopic rod (49), and the upper part of the hollow vertical connecting rod (45) is rotatably connected with the upper end of the furnace cover (2) through a second bearing (21);
the hollow blades (46) are arranged at the lower part of the hollow vertical connecting rod (45) at intervals, the hollow blades (46) are communicated with the hollow vertical connecting rod (45), and the hollow blades (46) are provided with vent holes (461);
a sampling pipe (47) of a sampling detection device is connected to the furnace cover (2);
the furnace cover (2) is connected with an exhaust pipe (48) for connecting with a waste gas treatment device;
the oxygen blowing device comprises: the first pipeline (5) is fixedly connected with the upper part of the hollow vertical connecting rod (45), the first pipeline (5) is connected with a first end of a three-way joint, a second end of the three-way joint is connected with an oxygen source through a second pipeline, a third end of the three-way joint is connected with an argon source through a third pipeline, and the second pipeline and the third pipeline are both provided with electromagnetic valves;
the rotating motor (42), the electric telescopic rod (49) and the electromagnetic valve are all electrically connected with the controller.
8. The process for manufacturing a high pressure hydrogen carbon steel valve casting according to claim 6,
the controller passes through timing circuit connection oxygen blast drive circuit, and above-mentioned oxygen blast drive circuit connects the oxygen blowing device, timing circuit includes:
a fourth resistor (R4) having one end connected to the controller;
a third operational amplifier (U3), the inverting input end of which is grounded through a first resistor (R1), and the non-inverting input end of which is connected with the other end of the fourth resistor (R4);
a fifth resistor (R5) and a sixth resistor (R6), wherein one end of the fifth resistor (R5) is connected with the non-inverting input end of the third operational amplifier (U3), the other end of the fifth resistor is connected with the first end of the sixth resistor (R6), the second end of the sixth resistor (R6) is grounded, and the first end of the sixth resistor (R6) is also connected with the output end of the third operational amplifier (U3);
an eighth resistor (R8) having one end connected to the output end of the third operational amplifier (U3);
a first transistor (Q1), the base of which is connected with the other end of the eighth resistor (R8);
a ninth resistor (R9), one end of which is connected with the collector of the first transistor (Q1), and the other end of which is connected with the output end of the third operational amplifier (U3);
a seventh resistor (R7), one end of which is connected with the base of the first transistor (Q1), and the other end of which is connected with the emitter of the first transistor (Q1) and grounded;
a third capacitor (C3), one end of which is connected with the collector of the first transistor (Q1) and the other end of which is connected with the emitter of the first transistor (Q1);
a fourth operational amplifier (U4), wherein the non-inverting input end of the fourth operational amplifier (U4) is connected with the collector of the first transistor (Q1), and the inverting input end of the fourth operational amplifier (U4) is connected with a power supply through an eleventh resistor (R11);
a tenth resistor (R10) having one end connected to the inverting input terminal of the fourth operational amplifier (U4) and the other end grounded;
the controller still is connected with overvoltage crowbar, overvoltage crowbar includes:
the first end of the adjustable shunt reference source (U6) is connected with a controller power voltage (V1), the second end of the adjustable shunt reference source is connected with one end of a second capacitor (C2), and the third end of the adjustable shunt reference source is connected with one end of a fourteenth resistor (R14);
a second operational amplifier (U2), wherein the non-inverting input end is connected with the other end of the fourteenth resistor (R14), and the inverting input end is connected with the controller power voltage (V1) through a twelfth resistor (R12);
a thirteenth resistor (R13), one end of which is connected with the inverting input end of the second operational amplifier (U2), and the other end of which is connected with the output end of the second operational amplifier (U2);
the inverting input end of the first operational amplifier (U1) is connected with the output end of the second operational amplifier (U2), and the non-inverting input end of the first operational amplifier is connected with the other end of the second capacitor (C2);
a second transistor (Q2), wherein the base electrode is connected with the output end of the first operational amplifier (U1), and the emitter electrode is connected with the power supply voltage (V1) of the controller;
one end of the first capacitor (C1) is connected with the non-inverting input end of the first transistor (Q1), and the other end of the first capacitor is connected with the controller;
one end of the second resistor (R2) is connected with the collector of the second transistor (Q2), and the other end of the second resistor (R2) is connected with the controller;
and the anode of the photoelectric coupler is connected with the collector of the second transistor triode (Q2), the cathode of the photoelectric coupler is connected with the controller power voltage (V1), the emitter of the photoelectric coupler is connected with the controller power voltage (V1) through a third resistor (R3), and the collector of the photoelectric coupler is connected with the controller.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911230041.9A CN111304514B (en) | 2019-12-04 | 2019-12-04 | Manufacturing process of high-pressure hydrogen carbon steel valve casting |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911230041.9A CN111304514B (en) | 2019-12-04 | 2019-12-04 | Manufacturing process of high-pressure hydrogen carbon steel valve casting |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111304514A CN111304514A (en) | 2020-06-19 |
| CN111304514B true CN111304514B (en) | 2021-02-05 |
Family
ID=71157455
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911230041.9A Active CN111304514B (en) | 2019-12-04 | 2019-12-04 | Manufacturing process of high-pressure hydrogen carbon steel valve casting |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111304514B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0246939A2 (en) * | 1986-04-21 | 1987-11-25 | Kawasaki Steel Corporation | Fe-Cr-Al stainless steel having high oxidation resistance and spalling resistance and Fe-Cr-Al steel foil for catalyst substrate of catalytic converter |
| CN101956121A (en) * | 2010-10-13 | 2011-01-26 | 江苏万恒铸业有限公司 | Manufacture process of high-pressure hydro-stainless steel valve casting |
| CN102000807A (en) * | 2010-10-13 | 2011-04-06 | 江苏万恒铸业有限公司 | Manufacturing process of high-pressure hydro-carbon steel valve castings |
| CN204385232U (en) * | 2014-12-06 | 2015-06-10 | 黑龙江建龙钢铁有限公司 | Lf ladle refining furnace |
| CN206289274U (en) * | 2016-12-29 | 2017-06-30 | 马鞍山市中桥金属材料有限公司 | A kind of LF furnace apparatus |
| CN107904359A (en) * | 2017-12-19 | 2018-04-13 | 天津基纳科技发展有限公司 | A kind of refining of metal composition and its application |
-
2019
- 2019-12-04 CN CN201911230041.9A patent/CN111304514B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0246939A2 (en) * | 1986-04-21 | 1987-11-25 | Kawasaki Steel Corporation | Fe-Cr-Al stainless steel having high oxidation resistance and spalling resistance and Fe-Cr-Al steel foil for catalyst substrate of catalytic converter |
| CN101956121A (en) * | 2010-10-13 | 2011-01-26 | 江苏万恒铸业有限公司 | Manufacture process of high-pressure hydro-stainless steel valve casting |
| CN102000807A (en) * | 2010-10-13 | 2011-04-06 | 江苏万恒铸业有限公司 | Manufacturing process of high-pressure hydro-carbon steel valve castings |
| CN204385232U (en) * | 2014-12-06 | 2015-06-10 | 黑龙江建龙钢铁有限公司 | Lf ladle refining furnace |
| CN206289274U (en) * | 2016-12-29 | 2017-06-30 | 马鞍山市中桥金属材料有限公司 | A kind of LF furnace apparatus |
| CN107904359A (en) * | 2017-12-19 | 2018-04-13 | 天津基纳科技发展有限公司 | A kind of refining of metal composition and its application |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111304514A (en) | 2020-06-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112481551B (en) | Steel WB36V for power station and smelting and continuous casting production process thereof | |
| CN103642976B (en) | A kind of smelting technology of H13 steel | |
| CN107829029B (en) | Smelting process method of ZG022Cr22Ni5Mo3N material duplex stainless steel | |
| CN105969932B (en) | A kind of method for making steel control hydrogen | |
| CN110643779A (en) | Ultra-low carbon steel top slag control production method | |
| CN108913983B (en) | Smelting method of FV520B steel with strong corrosion resistance and impact toughness | |
| CN103045793B (en) | Vacuum smelting device for converter and use method of vacuum smelting device | |
| CN212432282U (en) | Molten iron tank liquid level detection system | |
| CN111304514B (en) | Manufacturing process of high-pressure hydrogen carbon steel valve casting | |
| US6264716B1 (en) | Process for controlling the stirring energy delivered by a gas flowing through a liquid | |
| CN108504819B (en) | Process and device for smelting low-micro ferrochrome through AOD and VOD duplex | |
| CN111518992B (en) | Tank type single-nozzle refining furnace and vacuum refining method | |
| US4027095A (en) | Hermetically sealed arc furnace | |
| CN104561434A (en) | Low-phosphorus steel smelting process | |
| CN115595401B (en) | Steel refining equipment and steel-making method for improving cleanliness of molten steel | |
| JPS628484B2 (en) | ||
| CN110468256B (en) | Pretreatment process for desiliconizing, dephosphorizing and desulfurizing molten iron by KR-OB method | |
| CN111270045B (en) | Intermediate frequency furnace cast steel smelting process method | |
| CN105039649B (en) | A kind of method of use argon oxygen decarburizing furnace smelting high carbon high Mn content molten steel | |
| CN103436807B (en) | A kind of low-carbon-equivalent high-strength tenacity cast steel | |
| CN116135997A (en) | Air blowing deoxidizing device and method for non-vacuum induction furnace top | |
| CN112593045A (en) | High-temperature alloy smelting slagging process for intermediate frequency furnace | |
| Ahlin | Nitrogen Removal in a Vacuum Tank Degasser: An Investigation on the Nitrogen Removal Performance | |
| CN115323102B (en) | Converter smelting method for smelting aluminum killed steel with RH high efficiency | |
| CN115838891A (en) | Smelting method for producing high manganese steel by using foundry returns |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |