CN113441910A - Ultra-thick-wall quality-adjusting pipe and preparation method thereof - Google Patents
Ultra-thick-wall quality-adjusting pipe and preparation method thereof Download PDFInfo
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- CN113441910A CN113441910A CN202110672274.5A CN202110672274A CN113441910A CN 113441910 A CN113441910 A CN 113441910A CN 202110672274 A CN202110672274 A CN 202110672274A CN 113441910 A CN113441910 A CN 113441910A
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- B—PERFORMING OPERATIONS; TRANSPORTING
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- 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
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Abstract
The invention provides an ultra-thick wall quality-regulating pipe and a preparation method thereof. The preparation method of the ultra-thick-wall quality-control pipe comprises the following steps: solid bar boring: boring the center of the solid bar to obtain an ultra-thick-wall pipe; a heating step: heating the ultra-thick-wall pipe to obtain the fully austenitized ultra-thick-wall pipe; quenching and cooling: carrying out quenching cooling treatment on the ultra-thick-wall pipe subjected to full austenitizing to obtain a quenched and cooled ultra-thick-wall pipe; according to the invention, the solid bar is subjected to center boring to obtain the ultra-thick-wall pipe, and then the ultra-thick-wall pipe is quenched and tempered by adopting an external spraying and internal spraying quenching and cooling process, so that the mechanical property from the wall thickness 1/2 of the ultra-thick-wall pipe to the central region is improved, and especially the problem of unqualified longitudinal impact from the wall thickness 1/2 to the central region when the solid quenched and tempered bar is used after boring is solved.
Description
Technical Field
The invention belongs to the technical field of steel pipe heat treatment, and particularly relates to an ultra-thick wall quality-modulated pipe and a preparation method thereof.
Background
Because the center of the steel for the oil and gas tool needs to transmit media, oil and gas equipment suppliers generally purchase hardened and tempered pipes or solid hardened and tempered bars for use after boring the center. At present, the steel pipes with partial large-size outer diameter (D is more than 160mm) and thick-wall pipes D/S is less than 3, and the wall thickness exceeds the limit of hot-rolled steel pipe production equipment, so that the mass production cannot be realized; the cooling speed of the central part of the large-size solid bar (D is more than 160mm) in the quenching and tempering process is low, and the transformation of a martensite structure is insufficient, so that the mechanical property requirement from the wall thickness 1/2 to the central area cannot be met.
Disclosure of Invention
Aiming at the defects of the prior art, one of the purposes of the invention is to provide a preparation method of an ultra-thick-wall quality-control pipe, which is characterized in that an ultra-thick-wall pipe is obtained by carrying out central boring on a solid bar, and then the ultra-thick-wall pipe is subjected to quality control by adopting a quenching and cooling process of external spraying and internal spraying, so that the mechanical property from the wall thickness 1/2 of the ultra-thick-wall pipe to the central region is improved, and particularly, the problem that the longitudinal impact from the wall thickness 1/2 to the central region is unqualified when the solid quality-control bar is used after boring is solved.
In order to achieve the purpose, the invention adopts the following technical scheme:
a preparation method of the ultra-thick wall quality-control pipe comprises the following steps:
solid bar boring: boring the center of the solid bar to obtain an ultra-thick-wall pipe;
a heating step: heating the ultra-thick-wall pipe to obtain the ultra-thick-wall pipe after full austenitization;
quenching and cooling: carrying out quenching cooling treatment on the fully austenitized ultra-thick wall pipe to obtain a quenched and cooled ultra-thick wall pipe;
tempering: and tempering the quenched and cooled ultra-thick-wall pipe to obtain the ultra-thick-wall quality-control pipe.
In the above method for manufacturing the ultra-thick-wall tempered pipe, as a preferred embodiment, in the solid bar boring step, the solid bar is CrMo alloy steel; preferably, the grade of the CrMo alloy steel is one selected from 25-45 CrMo, 25-45 CrMnMo and 25-45 CrNiMo.
In the above method for manufacturing the ultra-thick-walled tempering pipe, as a preferred embodiment, the solid bar has an outer diameter of 165mm to 250mm (e.g., 170mm, 190mm, 210mm, 230mm, 250mm), and a length of 4m to 12m (e.g., 4.5m, 6m, 7.5m, 9m, 10.5m, 12 m).
In the above method for preparing the ultra-thick-wall quality-control pipe, as a preferred embodiment, in the solid bar boring step, after boring, the inner diameter of the pipe is 50mm to 80mm (e.g. 50mm, 60mm, 70mm, 80 mm); preferably, the pipe is a steel pipe with D/S < 3.
In the above method for producing an ultra-thick-walled tempering tube, as a preferred embodiment, in the heating step, the heating temperature is 750 to 1020 ℃ (such as 760 ℃, 820 ℃, 880 ℃, 940 ℃, 960 ℃, 980 ℃, 1000 ℃); the heating time is 190 min-800 min (such as 200min, 300min, 400min, 500min, 600min, 700min, 800 min); preferably, the heating treatment adopts a stepping heating furnace; the heating in the application mainly aims at enabling the ultra-thick-wall pipe after boring to be fully austenitized, and the structure cannot be fully austenitized due to low heating temperature or too short time, so that the structure cannot be fully transformed into martensite after cooling, and the mechanical property is low; the heating temperature is higher or the heating time is too long, so that the austenite grain size is large and the impact toughness is lower; the stepping heating furnace is used in the application, so that continuous production can be realized, and the production cost is low.
In the above method for manufacturing an ultra-thick-wall tempered pipe, as a preferred embodiment, in the step of quenching and cooling, the quenching treatment is an external spraying and internal spraying process; preferably, the flow rate of the outer shower water is 2200m3/h～5000m3H (e.g. 2500 m)3/h、3000m3/h、3500m3/h、4000m3/h、4500m3H), the external spraying time is 5 s-20 s (such as 5s, 8s, 11s, 14s and 17s), and the internal spraying water flow is 80m3/h～500m3H (e.g., 100 m)3/h、200m3/h、300m3/h、400m3/h、500m3H), the internal spraying time is 20 s-200 s (such as 40s, 80s, 120s, 160s and 200 s); preferably, the temperature of the cooling water is 4-38 ℃; the method adopts an external spraying and internal spraying process, so that the heated ultra-thick-wall pipe can be rapidly cooled, the martensite content in the structure is increased, and the mechanical property from the wall thickness 1/2 of the ultra-thick-wall pipe to the central area is improved; in the application, the cooling speed of the pipe is low due to the fact that the flow of external water spraying and internal water spraying is small or the cooling time is short or the temperature of cooling water exceeds 38 ℃, the structure cannot be fully transformed into martensite after quenching, the mechanical property is low, huge quenching stress is generated due to the fact that the cooling speed is too high, and the pipe is prone to deformation or cracking.
In the above method for manufacturing an ultra-thick-walled tempering pipe, as a preferred embodiment, in the tempering step, the tempering temperature is 525 ℃ to 720 ℃ (for example, 525 ℃, 570 ℃, 615 ℃, 660 ℃, 705 ℃), and the tempering time is 320min to 1300min (for example, 350min, 450min, 550min, 650min, 750min, 850min, 950min, 1050min, 1150min, 1250 min); preferably, the tempering treatment adopts a stepping heating furnace; the tempering aims at reducing brittleness, improving toughness and eliminating or reducing internal stress in the quenching step, and the lower tempering temperature can cause lower impact; higher tempering temperatures result in lower strength.
The invention also aims to provide the ultra-thick-wall quality-control pipe, which is prepared by adopting the preparation method.
Compared with the prior art, the invention has the following positive effects:
(1) the invention provides a preparation method which is simple to operate and can carry out continuous production, aiming at the defect that large-size thick-wall pipes with outer diameters (D is more than 160mm) and D/S (outer diameter/wall thickness) less than 3 cannot be produced in mass due to the fact that the wall thickness exceeds the limit of hot-rolled steel pipe production equipment.
(2) According to the invention, the solid bar is subjected to center boring operation to obtain the ultra-thick-wall pipe, and then the ultra-thick-wall pipe is tempered by adopting an external spraying and internal spraying process, so that the problem that longitudinal impact from the wall thickness 1/2 to the central region is unqualified when the solid tempered bar is used after boring in the prior art is solved.
(3) According to the invention, through adjusting the external spraying and internal spraying process, the cooling speed of the inside and the outside of the ultra-thick-wall pipe is improved, and the martensite content in the structure is increased, so that the mechanical property from the wall thickness 1/2 position of the ultra-thick-wall pipe to the central region is improved.
Drawings
FIG. 1 is a schematic view of the external shower and internal spray process of the present invention.
Fig. 2 is a cross-sectional view of the ultra-thick wall tubing of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments that can be derived by one of ordinary skill in the art from the embodiments given herein are intended to be within the scope of the present invention.
The solid bar used in the following examples is 4130M 110KSI (chemical composition equivalent to 30CrMnMo), and the mass percentages of the respective elemental components are shown in Table 1; the boring equipment is a deep hole drilling and boring machine, and the manufacturer is Texas Boao mechanical Co., Ltd; the heating equipment is a stepping heating furnace, and the manufacturer is a Luoyi thermal engineering (Tianjin) Co., Ltd; the quenching cooling equipment is a 325 quenching machine, the 325 quenching machine is an external spraying and internal spraying type quenching machine, the manufacturer is Zhongzhuicheng, the drawing of figure 1 shows an external spraying and internal spraying cooling device, the external spraying is used for cooling the outer surface of the steel pipe from top to bottom, the internal spraying is used for cooling the inner wall of the steel pipe from left to right, and in the cooling process of the steel pipe, a carrier roller below the 325 quenching machine drives the steel pipe to rotate so as to ensure that the outer surface and the inner surface of the steel pipe are uniformly cooled at 360 ℃.
TABLE 1 solid bar code 4130M 110KSI each element component mass percentage (balance Fe and unavoidable impurities)
Example 1
S1, boring a solid bar: boring a solid bar with the diameter of 195mm and the length of 4.8m by using deep hole drilling and boring machine equipment to obtain a pipe with the outer diameter of 195mm, the inner diameter of 50mm and the wall thickness of 72.5mm, wherein D/S is 2.69;
s2, heating: heating the pipe obtained in the step S1 in a stepping heating furnace at 905 +/-5 ℃ for 583 min;
s3, quenching and cooling: quenching the pipe obtained in the step S2 in a 325 quenching machine, wherein the flow rate of externally sprayed water is 3600m3The time of external shower is 14 s; the internal water spraying flow is 160m3The internal spraying time is 34s, and the cooling water temperature is 20 ℃;
s4, tempering: and (3) tempering the pipe obtained in the step-by-step heating furnace at the tempering temperature of 650 +/-5 ℃ for 980 min.
Example 2
S1, boring a solid bar: boring a solid bar with the diameter of 195mm and the length of 4.8m by using deep hole drilling and boring machine equipment to obtain a pipe with the outer diameter of 195mm, the inner diameter of 55mm and the wall thickness of 70mm, wherein D/S is 2.79;
s2, heating: heating the pipe obtained in the step S1 in a stepping heating furnace at 905 +/-5 ℃ for 574 min;
s3, quenching and cooling: quenching the pipe obtained in the step S2 in a 325 quenching machine, wherein the flow rate of externally sprayed water is 3600m3The time of external shower is 14 s; the internal water spraying flow is 160m3The internal spraying time is 34s, and the cooling water temperature is 20 ℃;
s4, tempering: and (3) tempering the pipe obtained in the step-by-step heating furnace at the tempering temperature of 650 +/-5 ℃ for 964 min.
Example 3
S1, boring a solid bar: boring a solid bar with the diameter of 195mm and the length of 4.8m by using deep hole drilling and boring machine equipment to obtain a pipe with the outer diameter of 195mm, the inner diameter of 60mm and the wall thickness of 67.5mm, wherein D/S is 2.89;
s2, heating: heating the pipe obtained in the step S1 in a stepping heating furnace at 905 +/-5 ℃ for 565 min;
s3, quenching and cooling: quenching the pipe obtained in the step S2 in a 325 quenching machine, wherein the flow rate of externally sprayed water is 3600m3The time of external shower is 14 s; the internal water spraying flow is 160m3The internal spraying time is 34s, and the cooling water temperature is 20 ℃;
s4, tempering: and (3) tempering the pipe obtained in the step-by-step heating furnace at the tempering temperature of 650 +/-5 ℃ for 949 min.
Example 4
Example 4 the same as example 1 except that the flow rate of the shower water for quenching and cooling of S3 was slightly different from that of example 1, and in example 4, the flow rate of the shower water was 4600m3/h。
Example 5
Example 5 the same as example 1 except that the flow rate of the external shower water for quenching and cooling in S3 was slightly different from that in example 1, and in example 5, the flow rate of the external shower water was 2600m3/h。
Example 6
Example 6 the same as example 1 except that the flow rate of the internal water jet for quenching and cooling of S3 was slightly different from that of example 1,example 6 the inner water spray flow rate was 260m3/h。
Example 7
Example 7 was conducted in the same manner as example 1 except that the internal water injection flow rate in the quenching cooling of S3 was slightly different from that in example 1, and the internal water injection flow rate in example 7 was 100m3/h。
Comparative example 1
S1, heating: heating a solid bar with the diameter of 195mm and the length of 4.8m in a stepping heating furnace at the temperature of 905 +/-5 ℃ for 583 min;
s2, quenching and cooling: quenching the solid bar heated in the S1 in a 325 quenching machine, wherein the outer water flow is 3600m3The external spraying time is 14s, and the cooling water temperature is 20 ℃;
s3, tempering: tempering the solid bar quenched in the S2 in a stepping heating furnace at the tempering temperature of 650 +/-5 ℃ for 980 min;
s4, boring a solid bar: the solid rod obtained in S3 was subjected to boring operation using a deep hole drilling and boring machine to obtain a pipe material having an outer diameter of 195mm, an inner diameter of 50mm and a wall thickness of 72.5mm, where D/S was 2.69.
Comparative example 2
Comparative example 2 the heating temperature of comparative example 2 was 1030 ℃ and the same as that of example 1, except that the heating temperature of S2 was slightly different from that of example 1.
Comparative example 3
Comparative example 3 the same as example 1 except that the quenching cooling of S3 was slightly different from that of example 1, and the flow rate of the shower water in comparative example 3 was 2000m3The time of external shower is 14 s; the internal water spraying flow is 160m3/h, the internal spraying time is 34s, and the cooling water temperature is 20 ℃.
Comparative example 4
Comparative example 4 the same as example 1 except that the quenching cooling of S3 was slightly different from that of example 1, and the flow rate of the shower water in comparative example 4 was 6000m3The time of external shower is 14 s; the internal water spraying flow is 160m3/h, the internal spraying time is 34s, and the cooling water temperature is 20 ℃.
Performance detection
The ultra-thick wall temper pipes prepared in the present application by examples 1 to 7 and comparative examples 1 to 4 were subjected to a tensile test (according to ASTM E8/E8M-16ael "tensile test method for metallic material"), a longitudinal low temperature impact test at 21 ℃ (according to ASTM E23-2018 "test method for notched bar impact test for metallic material"), and a test of surface hardness (according to ASTM E10-2018 "standard test method for brinell hardness of metallic material"), and the test results are shown in table 2.
TABLE 2 mechanical Property data for ultra-thick walled conditioning pipes prepared in examples 1-7 and comparative examples 1-4
The above description is only exemplary of the invention and should not be taken as limiting the invention, as any modification, equivalent replacement, or improvement made within the spirit and principle of the invention is intended to be covered by the appended claims.
Claims (10)
1. The preparation method of the ultra-thick-wall quality-control pipe is characterized by comprising the following steps:
solid bar boring: boring the center of the solid bar to obtain an ultra-thick-wall pipe;
a heating step: heating the ultra-thick-wall pipe to obtain the ultra-thick-wall pipe after full austenitization;
quenching and cooling: carrying out quenching cooling treatment on the fully austenitized ultra-thick wall pipe to obtain a quenched and cooled ultra-thick wall pipe;
tempering: and tempering the quenched and cooled ultra-thick-wall pipe to obtain the ultra-thick-wall quality-control pipe.
2. The method of claim 1, wherein in the solid bar boring step, the solid bar is a CrMo alloy steel; preferably, the grade of the CrMo alloy steel is one selected from 25-45 CrMo, 25-45 CrMnMo and 25-45 CrNiMo.
3. The method of claim 1 or 2, wherein in the solid bar boring step, the diameter of the solid bar is 165-250 mm, and the length of the solid bar is 4-12 m.
4. The method for preparing the ultra-thick wall tempering pipe according to claim 3, wherein in the solid bar boring step, after boring operation, the inner diameter of the pipe is 50-80 mm; preferably, the pipe is a steel pipe with D/S < 3.
5. The method of claim 1, wherein in the heating step, the heating temperature is 750-1020 ℃ and the heating time is 190-800 min.
6. The method of claim 5, wherein in the heating step, the heating process is performed using a walking beam furnace.
7. The method for manufacturing an ultra-thick wall quality-control pipe according to claim 1, wherein in the quenching and cooling step, the quenching and cooling treatment is an external spraying and internal spraying process.
8. The method of claim 7, wherein in the outer shower and inner shower process, the outer shower water flow rate is 2200m3/h～5000m3The external spraying time is 5-20 s, and the internal water spraying flow is 80m3/h～500m3The internal water spraying time is 20-200 s; preferably, the cooling water temperature is between 4 ℃ and 38 ℃.
9. The method for preparing the ultra-thick wall tempering pipe according to claim 1, wherein in the tempering step, the tempering temperature is 525-720 ℃, and the tempering time is 320-1300 min; preferably, the tempering treatment is performed by a step-type heating furnace.
10. An ultra-thick walled tempering pipe prepared by the method of any one of claims 1 to 9.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08104922A (en) * | 1994-10-07 | 1996-04-23 | Nippon Steel Corp | Production of high strength steel pipe excellent in low temperature toughness |
| CN102482727A (en) * | 2009-08-21 | 2012-05-30 | 住友金属工业株式会社 | Method for manufacturing thick-walled seamless steel pipe |
| CN103695623A (en) * | 2013-12-20 | 2014-04-02 | 鞍钢股份有限公司 | Treatment method of special thick-walled seamless tube |
| CN206811149U (en) * | 2017-05-31 | 2017-12-29 | 河南华电金源管道有限公司 | A kind of heavy wall boring cutter for borehole frock |
| CN109371203A (en) * | 2018-11-23 | 2019-02-22 | 包头钢铁（集团）有限责任公司 | A kind of intermittent heat treatment process of heavy wall 12Cr1MoVG high-pressure boiler tube |
-
2021
- 2021-06-17 CN CN202110672274.5A patent/CN113441910A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08104922A (en) * | 1994-10-07 | 1996-04-23 | Nippon Steel Corp | Production of high strength steel pipe excellent in low temperature toughness |
| CN102482727A (en) * | 2009-08-21 | 2012-05-30 | 住友金属工业株式会社 | Method for manufacturing thick-walled seamless steel pipe |
| CN103695623A (en) * | 2013-12-20 | 2014-04-02 | 鞍钢股份有限公司 | Treatment method of special thick-walled seamless tube |
| CN206811149U (en) * | 2017-05-31 | 2017-12-29 | 河南华电金源管道有限公司 | A kind of heavy wall boring cutter for borehole frock |
| CN109371203A (en) * | 2018-11-23 | 2019-02-22 | 包头钢铁（集团）有限责任公司 | A kind of intermittent heat treatment process of heavy wall 12Cr1MoVG high-pressure boiler tube |
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