High-performance anti-corrosion wear-resistant dual-phase alloy oil pipe and manufacturing method thereof

Abstract

The invention discloses a high-performance anti-corrosion wear-resistant dual-phase alloy oil pipe and a manufacturing method thereof, and relates to the technical field of oil exploitation equipment. The invention discloses a manufacturing method of a high-performance anti-corrosion wear-resistant dual-phase alloy oil pipe. The manufacturing method comprises the following steps: removing rust and oxide skin on the surface of an inner hole of the oil pipe; the oil pipe is filled with a permeating agent, and the two ends of the oil pipe are blocked; the temperature control process in the heating furnace comprises the steps that before the oil pipe is conveyed to the heating furnace, the furnace temperature is increased to 650-800 DEG C in advance; after the oil pipe is conveyed to the heating furnace, the furnace temperature is increased to 800 DEG C, and heat preservation is conducted for And the furnace temperature continues to rise to 950-1000 DEG C and is kept for 4-6 h. According to the manufacturing method of the high-performance corrosion-resistant and wear-resistant dual-phase alloy oil pipe, the thickness of the dual-phase alloy layer in the high-performance corrosion-resistant and wear-resistant dual-phase alloy oil pipe prepared through the method is 0.1 + / -0.02 mm, and the oil pipe can have better corrosion resistance and wear resistance under the condition that normal use of the oil pipe is guaranteed; and the condition that the wear-resistant and corrosion-resistant permeation layer in the oil pipe falls off is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of oil production equipment, and in particular to a high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe and a manufacturing method thereof. Background Art

[0002] The oil pipe in the oil field is a steel pipe used to transport oil, natural gas and other fluids during oil exploration and production. The oil pipe is an indispensable part of the oil well operation system. The main function of the oil pipe in the oil field is to provide a sealed channel so that underground oil, natural gas and other resources can be safely and efficiently transported from underground to the surface.

[0003] With the rapid development of my country's oilfield industry, oil pipes will fail during long-term operation, which is also an important factor affecting the frequent shutdown of oil wells. Common forms of damage to oil pipes are generally eccentric wear and corrosion damage on the inner surface of the oil pipe, which seriously affect the service life of the oil pipe and the efficiency of oilfield operations.

[0004] At present, in order to solve the problems of eccentric wear and corrosion of oil pipes, some relevant researchers have proposed solutions of adding inner lining oil pipes or adding electroplating coatings in oil pipes; however, the inventors believe that the above two solutions have the following technical problems:

[0005] (1) Although the lined tubing has good corrosion resistance and anti-eccentric wear performance, the inner diameter of the tubing is small due to the addition of a lining layer on the inner wall of the tubing. Many downhole tools cannot be lowered, which increases the difficulty of the operation.

[0006] (2) The corrosion resistance and anti-eccentric wear performance of electroplated oil pipes are acceptable when in good condition, but the bonding strength between the electroplated coating and the oil pipe substrate is not high, and the coating is easy to fall off. In the best case, the corrosion resistance and wear resistance of the oil pipe are reduced, and in the worst case, the fallen coating falls into the oil pump and causes the pump to get stuck.

[0007] Therefore, how to solve the above technical problems is a technical problem currently faced by general technicians in this field.

[0008] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0009] In view of the above technical problems, an embodiment of the present invention provides a high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe and a manufacturing method thereof to solve the problems raised in the above background technology.

[0010] A method for manufacturing a high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe comprises the following steps:

[0011] Remove rust and scale on the inner hole surface of the oil pipe; specifically, remove rust and scale on the inner hole surface by sandblasting or other methods, and the rust removal level reaches SA2.5;

[0012] Fill the oil pipe with penetrant and seal both ends of the oil pipe;

[0013] The oil pipe filled with penetrant is sent to the heating furnace for heat treatment. The temperature control process in the heating furnace includes:

[0014] Before the oil pipe is sent to the heating furnace, the furnace temperature is pre-raised to 650-800℃;

[0015] After the oil pipe is sent to the heating furnace, the furnace temperature is raised to 800°C and kept warm for 0.5-2h; preferably, the furnace temperature is raised to 800°C and kept warm for 1h;

[0016] The furnace temperature continues to rise to 950-1000°C and is kept warm for 4-6 hours; preferably, the furnace temperature continues to rise to 950-1000°C and is kept warm for 5 hours;

[0017] Turn off the heating furnace and lower the furnace temperature to 850-900℃;

[0018] After the furnace temperature drops to 850-900℃, the oil pipe is removed from the heating furnace and sent to the air cooling room, where it is cooled to room temperature for normalizing.

[0019] After the oil pipe is normalized in the air-cooled chamber, a bidirectional alloy wear-resistant and corrosion-resistant layer composed of Fe2B and FeSi is formed on the inner surface of the oil pipe;

[0020] Among them, the penetrant components include: B4C, Na2B4O7, Si, NH4Cl and rare earth.

[0021] It should be noted that the purpose of raising the furnace temperature to 650-800℃ before the oil pipe is sent to the heating furnace is to avoid the oil pipe filled with penetrant being heated below 650℃ for a long time after being loaded into the furnace, so that the NH4Cl in the penetrant is decomposed prematurely.

[0022] After the oil pipe is sent to the heating furnace, the furnace temperature rises to 800℃ and is kept warm for 0.5-2h. The purpose is: this process mainly plays a role in temperature uniformity, avoiding excessive temperature difference in the oil pipe in the furnace due to rapid heating, and at the same time has a certain drying effect on the penetrant in the furnace.

[0023] The purpose of continuing to raise the furnace temperature to 950-1000℃ and keeping it warm for 4-6h is: this process is the strong penetration stage of the penetrant. Previous studies have found that raising the furnace temperature to 950-1000℃ and keeping it warm for 4-6h can ensure the formation of a high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe duplex alloy layer with a thickness of 0.1±0.02mm; the hardness of the bidirectional alloy wear-resistant and corrosion-resistant layer can reach HV1000-HV2300.

[0024] Preferably, in the step of filling the penetrant in the oil pipe and sealing both ends of the oil pipe, the method of sealing both ends of the oil pipe includes: turning an external thread at each end of the outer side of the oil pipe, and threading a screw plug at each end of the oil pipe; the screw plug is a cap-shaped structure, and the inner wall of the screw plug is turned with an internal thread.

[0025] Preferably, the amount of the penetrant filled in the oil pipe satisfies: the penetrant fills the inner hole of the oil pipe. The specific standard for the penetrant filling the inner hole of the oil pipe is: after the penetrant fills the inner hole of the oil pipe and is sealed with a wire plug, after the oil pipe is vertically lifted by the lifting equipment, the height of the penetrant in the oil pipe from the upper end of the inner hole of the oil pipe is within 2 cm, which is qualified.

[0026] Preferably, a step of dripping alcohol into the furnace is added between the step of raising the furnace temperature to 800°C and keeping it warm for 0.5-2h after the oil pipe is sent to the heating furnace and the step of further raising the furnace temperature to 950-1000°C and keeping it warm for 4-6h.

[0027] Preferably, in the step of dripping alcohol into the furnace, the alcohol is dripped into the heating furnace at a rate of 150-350 drops / minute, and the alcohol is continuously dripped into the heating furnace for 2-3 hours. The purpose of this process is to consume oxygen in the furnace and prevent the surface oxidation of the oil pipe due to long-term heating.

[0028] Preferably, during air cooling to room temperature, the cooling rate in the air cooling chamber is controlled at 650-800° C. / h.

[0029] Preferably, the components in the penetrant include, by mass, 53-68 parts of B4C, 11-16 parts of Na2B4O7, 15-21 parts of Si, 8-12 parts of NH4Cl, and 1 part of rare earth; the penetrant is in granular form.

[0030] Among them, B4C and Na2B4O7 are B supply agents; Si is a Si supply agent; NH4Cl is a catalyst; and rare earth is a catalyst.

[0031] Preferably, after the oil pipe is normalized in the air cooling chamber, the penetrant in the oil pipe is cleaned and the oil pipe is straightened to make the straightness of the oil pipe within 1mm / m; and an oil pipe coupling is assembled at one end of the oil pipe. The purpose of straightening is to prevent serious rounding during subsequent threading; the threading at this stage is used for the oil pipe coupling.

[0032] A high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe is prepared by using the above-mentioned manufacturing method of the high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe.

[0033] Preferably, the inner surface of the oil pipe body is processed with a dual-phase alloy wear-resistant and corrosion-resistant permeability layer, and the main components of the dual-phase alloy wear-resistant and corrosion-resistant layer are Fe2B and FeSi.

[0034] A high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe and a method for manufacturing the same provided by an embodiment of the present invention have the following beneficial effects: The present invention has developed a method for manufacturing a high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe. The thickness of the duplex alloy layer in the high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe prepared by this method is 0.1±0.02mm, which can ensure that the oil pipe can be used normally while having better corrosion resistance and wear resistance, and the wear-resistant and corrosion-resistant permeation layer in the oil pipe will not fall off. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a structural schematic diagram of the high-performance anti-corrosion and wear-resistant bidirectional alloy oil pipe in the present invention;

[0036] Figure 2 For the present invention Figure 1 Cross-section view in the AA direction;

[0037] Figure 3 This is a morphology image of the bidirectional alloy wear-resistant and corrosion-resistant layer in the oil pipe of the present invention taken under a microscope;

[0038] Figure 4 This is a comparison diagram of the wear resistance of the present invention;

[0039] Figure 4 a is sample 1#; Figure 4 b is sample 2#; Figure 4 c is sample 3#; Figure 4 d is 4# sample;

[0040] Figure 5 The working method of the abrasive wear testing machine of the present invention;

[0041] Figure 6 This is a comparison result diagram of the medium corrosion resistance of the present invention;

[0042] Figure 6 a is treated with 25% HCl solution; Figure 6 b is treated with 33% H3PO4 solution; Figure 6 c: Treatment with 12% H2SO4 solution. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0044] In view of the above technical problems, an embodiment of the present invention provides a high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe and a manufacturing method thereof to solve the problems raised in the above background technology.

[0045] Example 1: Preparation of high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe

[0046] 1. Clean the inner hole: Take the qualified oil pipe 100, remove the rust and oxide scale on the surface of the inner hole by sandblasting or other methods, and the rust removal level reaches SA2.5.

[0047] 2. Turning process threads: Turn the external threads on both ends of the oil pipe with clean inner hole surface.

[0048] 3. Loading the penetrant: Use a feeder or other means to load the penetrant into the oil pipe, and screw on the plug after filling it. The components in the penetrant, by mass, include: 53 parts of B4C, 11 parts of Na2B4O7, 15 parts of Si, 8 parts of N2H4Cl, and 1 part of rare earth. The penetrant is in granular form.

[0049] 4. Heat treatment:

[0050] (1) After the furnace temperature is raised to 650-800 degrees Celsius, the oil pipe filled with penetrant is loaded onto the trolley and pushed into the trolley furnace.

[0051] (2) After loading into the furnace, the temperature is quickly raised to 800 degrees Celsius and kept at this temperature for 1 hour. This process mainly plays a role in equalizing the temperature, avoiding excessive temperature differences in the oil pipes in the furnace due to rapid heating; at the same time, it has a certain drying effect on the permeation agent in the furnace.

[0052] (3) After the temperature reaches 800 degrees Celsius, alcohol is dripped into the furnace at a rate of 150-350 drops / minute. The alcohol is continuously dripped into the heating furnace for 3 hours to consume oxygen in the furnace and prevent oxidation of the oil pipe surface due to long-term heating.

[0053] (4) Continue to raise the temperature to 950-1000 degrees Celsius and keep it warm for 5 hours. This process is the strong penetration stage to ensure the thickness of the duplex alloy layer of the high-performance anti-corrosion and wear-resistant duplex alloy oil pipe.

[0054] (5) Turn off the power and let the furnace cool down to 850-900 degrees Celsius before taking it out of the furnace. The trolley enters the air cooling room, turns on the fan for cooling, and adjusts the fan speed through the inverter to control the cooling speed at 650-800 degrees Celsius / hour, and air cools to room temperature. This process is the normalizing process. By controlling the cooling speed, the mechanical properties of the high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe can meet the standard requirements.

[0055] 5. Unloading the penetrant: Move the oil pipe out of the air cooling chamber after the normalizing operation is completed; unscrew the screw plug of the cooled oil pipe, pour out the penetrant from the oil pipe, and prepare for subsequent work.

[0056] 6. Straightening: Straighten the bent oil pipe to make its straightness within 1mm / m to prevent severe circular runout during subsequent threading.

[0057] 7. Remove drug residue: Use a ash thrower to clean the penetrant residue remaining in the oil pipe to prevent debris in the oil pipe from falling into the oil well when going down the well.

[0058] 8. Threading the oil pipe: Use a CNC lathe to process the oil pipe threads at both ends of the oil pipe.

[0059] 9. Upper coupling: Tighten the tubing coupling 110 at one end of the tubing. To improve the overall corrosion resistance of the high-performance anti-corrosion and wear-resistant bidirectional alloy tubing, an anti-corrosion treated tubing coupling, such as a copper-plated coupling, may be used.

[0060] 10. Water pressure testing: Use a hydraulic press to test the high-performance corrosion-resistant and wear-resistant bidirectional alloy oil pipe to detect whether there are defects in the pipe body and the sealing of the connection between the coupling and the oil pipe.

[0061] The results are as follows Figure 3 As shown; after heat treatment, a bidirectional alloy wear-resistant and anti-corrosion layer 101 composed of Fe2B and FeSi can be formed on the inner hole surface of the oil pipe, with a thickness of about 0.1mm; the hardness of the bidirectional alloy wear-resistant and anti-corrosion layer can reach HV1000-HV2300, and the hardness and thickness of the bidirectional alloy wear-resistant and anti-corrosion layer are obtained by testing with a microhardness tester.

[0062] It should be noted that in actual heating work, especially in the high temperature stage, the temperature control of the heating furnace may be a range rather than a single specific value; the temperature fluctuation of the heating furnace is usually within a certain tolerance range, but it will ensure the desired heat treatment effect. And the previous study found that according to the above method and strictly implementing the temperature value range of each temperature control stage, it can ensure that the oil pipe forms a high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe duplex alloy layer with a thickness of 0.1±0.02mm.

[0063] Example 2: Comparative experiment on wear resistance of the present invention

[0064] 1. Sample preparation: The sample size is 25mm*75mm*4.5mm;

[0065] The 1# specimen is made of 33Mn2V, and the surface is a bidirectional alloy wear-resistant and anti-corrosion layer composed of Fe2B and FeSi with a thickness of not less than 0.08mm; the 2# specimen is made of 40# steel with a hard chrome plating treatment on the surface, and the thickness of the chrome plating layer is ≥0.08mm; the 3# specimen is made of 20Cr, and the surface is carburized and quenched, and the thickness of the hardened layer is ≥0.5mm; the 4# specimen is made of 45# steel with a quenching treatment on the surface, and the thickness of the hardened layer is ≥0.5mm.

[0066] It should be noted that the processing methods of 2# sample, 3# sample and 4# sample are all processed using conventional technology; 1# sample is a partial fragment cut from the high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe prepared in Example 1.

[0067] 2. Use a balance with an accuracy of 0.0001g to weigh the weight of the four samples respectively; among them, the weight of sample #1 is m1, the weight of sample #2 is m2, the weight of sample #3 is m3, and the weight of sample #4 is m4.

[0068] 3. Four samples were installed on the abrasive wear tester for testing. The test conditions of the four groups of experiments were completely consistent. The weight of the test block was detected and recorded every 1 hour. The test was stopped when the wear-resistant layer on the surface of any sample was completely removed. The weight of the test block before the test minus the weight of the test block after the test was the weight loss of the test block in this experiment, that is, the amount of wear. The working method of the abrasive wear tester is detailed in Figure 5 .

[0069] 4. Comparison results of wear resistance Figure 4 As shown in the figure, the abrasive wear resistance of the 1# sample with Fe2B and FeSi on the surface is better than that of the electroplated chrome of the 2# sample, the carbonitriding of the 3# sample and the surface hardened steel of the 4# sample.

[0070] Example 3: Comparative experiment on the corrosion resistance of the present invention

[0071] 1. Sample preparation:

[0072] Test block size: square test block 50*25*4 (mm);

[0073] Test block material: 3 untreated 33Mn2V test blocks; 3 33Mn2V test blocks with a two-phase alloy infiltration layer on the surface (the thickness of the two-way infiltration layer is 0.085mm);

[0074] Three 33Mn2V test blocks with a dual-phase alloy infiltration layer on the surface are partial fragments cut from the high-performance corrosion-resistant and wear-resistant dual-phase alloy oil pipe prepared by the present invention; the preparation method of the high-performance corrosion-resistant and wear-resistant dual-phase alloy oil pipe in this embodiment is the same as that in the first embodiment;

[0075] Among them, the components of the penetrant in this embodiment are adjusted as follows: the components in the penetrant, by mass, include: 68 parts of B4C, 16 parts of Na2B4O7, 21 parts of Si, 12 parts of NH4Cl, and 1 part of rare earth.

[0076] 2. Corrosive medium: 1L of 25% HCl solution; 1L of 33% H3PO4 solution; 1L of 12% H2SO4 solution; respectively placed in three 2L beakers, the solution temperature is 56 degrees.

[0077] 3. Test method: Before the experiment, wipe the test block with alcohol, and use an analytical balance with an accuracy of lug to measure the weight of the test block, and record the weight m, in ug. Divide the test blocks into three groups (one 33Mn2V untreated test block in each group, and one 33Mn2V test block with a duplex alloy layer on the surface) and immerse them in three corrosive media respectively. The test blocks should be suspended for immersion to avoid sinking to the bottom or incomplete immersion. Place three beakers in a constant temperature environment of 56°C, weigh the test blocks every 1 hour, and record their weight mn; the unit is ug (the weight is m1 after one hour of experiment, m2 after two hours of experiment, ... m8 after eight hours of experiment);

[0078] Calculate weight loss δm (unit: ug / cm 2 ):δm=(m-mn) / 31; (31 is the surface area of ​​the test piece, unit: cm 2 ).

[0079] 4. Comparison results of wear resistance Figure 6 As shown; Medium corrosion resistance: 33Mn2V steel with Fe2B and FeSi on the surface has better resistance to sulfuric acid, phosphoric acid and sulfuric acid than 33Mn2V steel without any treatment.

[0080] The embodiments described above are only descriptions of the preferred implementation modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for manufacturing a high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe, characterized in that: The following steps are involved: Remove rust and oxide scale from the inner surface of the oil pipe; Fill the oil pipe with penetrant and seal both ends of the oil pipe; The oil pipe filled with penetrant is sent to the heating furnace for heat treatment. The temperature control process in the heating furnace includes: Before the oil pipe is sent to the heating furnace, the furnace temperature is pre-raised to 650-800℃; after the oil pipe is sent to the heating furnace, the furnace temperature is raised to 800℃ and kept warm for 0.5-2h; the furnace temperature continues to rise to 950-1000℃ and kept warm for 4-6h; the heating furnace is turned off to reduce the furnace temperature to 850-900℃; The oil pipe is then removed from the heating furnace and sent to an air cooling chamber, where it is cooled to room temperature for normalizing. After the oil pipe is normalized in the air-cooled chamber, a bidirectional alloy wear-resistant and corrosion-resistant layer composed of Fe2B and FeSi is formed on the inner surface of the oil pipe; Among them, the penetrant components include: B4C, Na2B4O7, Si, NH4Cl and rare earth.

2. The method for manufacturing a high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe according to claim 1, characterized in that: In the step of filling the oil pipe with a penetrant and sealing both ends of the oil pipe, the method of sealing both ends of the oil pipe includes: turning an external thread at both ends of the outer side of the oil pipe, and connecting a screw plug with each thread at both ends of the oil pipe; the screw plug is a cap-shaped structure, and the inner wall of the screw plug is turned with an internal thread.

3. The method for manufacturing a high performance corrosion resistant and wear resistant duplex alloy oil pipe according to claim 1, characterized in that: The amount of penetrant filled in the oil pipe is such that the inner hole of the oil pipe is fully filled with the penetrant.

4. The method for manufacturing a high performance corrosion resistant and wear resistant duplex alloy oil pipe according to claim 1, characterized in that: After the oil pipe is sent to the heating furnace, a step of adding alcohol dripping into the furnace is added between the step of raising the furnace temperature to 800°C and keeping it warm for 0.5-2h and the step of further raising the furnace temperature to 950-1000°C and keeping it warm for 4-6h.

5. The method for manufacturing a high performance corrosion resistant and wear resistant duplex alloy oil pipe according to claim 4, characterized in that: In the step of dripping alcohol into the furnace, the alcohol is dripped into the heating furnace at a speed of 150-350 drops / minute, and the alcohol is continuously dripped into the heating furnace for 2-3 hours.

6. The method for manufacturing a high performance corrosion resistant and wear resistant duplex alloy oil pipe according to claim 1, characterized in that: During air cooling to room temperature, the cooling rate in the air cooling chamber is controlled at 650-800℃ / h.

7. The method for manufacturing a high performance corrosion resistant and wear resistant duplex alloy oil pipe according to claim 1, characterized in that: The components in the penetrant, calculated by mass, include: 53-68 parts of B4C, 11-16 parts of Na2B4O7, 15-21 parts of Si, 8-12 parts of NH4Cl, and 1 part of rare earth.

8. A high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe, characterized in that: The high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe is prepared by the manufacturing method of claims 1-7.

9. The high performance corrosion resistant and wear resistant duplex alloy oil pipe according to claim 8, characterized in that: The inner surface of the oil pipe body is processed with a duplex alloy wear-resistant and corrosion-resistant permeable layer, and the main components of the duplex alloy wear-resistant and corrosion-resistant layer are Fe2B and FeSi.

10. The high performance corrosion resistant and wear resistant duplex alloy oil pipe according to claim 8, characterized in that: The thickness of the duplex alloy layer in the high-performance corrosion-resistant and wear-resistant duplex alloy oil pipe is 0.1±0.02mm.

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