阅读说明：本技术 一种钢管轧辊及钢管加工方法 (Steel pipe roller and steel pipe machining method ) 是由 胡大辉 于 2021-08-13 设计创作，主要内容包括：本发明公开了一种钢管轧辊及钢管加工方法,本发明通过改变辊体上孔型截面定位线的加工外径,可得到不同曲率的加工曲面,从而可获取更大的延伸系数,因此,本发明可将毛管一次性加工至小口径钢管,从而减少小口径钢管加工过程中的中间道次,进而减少酸洗、磷化、皂化以及退火等必要工序,以减少资源的浪费、降低成本以及降低环境污染。(The invention discloses a steel pipe roller and a steel pipe processing method, wherein the processing outer diameter of a pass section positioning line on a roller body is changed to obtain processing curved surfaces with different curvatures so as to obtain a larger elongation coefficient, so that a tubular billet can be processed to a small-caliber steel pipe at one time, thereby reducing intermediate passes in the processing process of the small-caliber steel pipe, further reducing necessary procedures such as acid washing, phosphorization, saponification, annealing and the like, and reducing the waste of resources, the cost and the environmental pollution.)

1. A steel pipe roll, comprising: the roller comprises a roller body (10), wherein the roller body (10) is sequentially provided with a reducing groove (20), a wall reducing groove (30) and a sizing groove (40) along the circumferential direction;

a first hole-type section positioning line and a second hole-type section positioning line are arranged on the reducing groove (20), wherein the reducing groove (20) is positioned in a region between the first hole-type section positioning line and the second hole-type section positioning line to form a reducing curved surface, and the outer diameter of a first steel pipe formed by machining a tubular billet through the reducing curved surface is between 37 and 42 mm;

a third hole-type section positioning line is arranged on the reduced wall groove (30), wherein a region of the reduced wall groove (30) between the second hole-type section positioning line and the third hole-type section positioning line forms a reduced wall curved surface, and the outer diameter of a second steel pipe formed by machining the first steel pipe through the reduced wall curved surface is between 31 and 33.4 mm;

the sizing groove (40) is provided with 9 fourth pass section positioning lines in sequence along the machining direction of the tubular billet, wherein the area of the sizing groove (40) between the 9 fourth pass section positioning lines forms a sizing curved surface, and the outer diameter of a finished steel pipe formed by machining the sizing curved surface is 15.1-22 mm.

2. The roll of steel pipe as claimed in claim 1, wherein the first pass section positioning line has a corresponding processed outer diameter of 45 mm.

3. The roll of steel pipes as claimed in claim 1, wherein the first steel pipe formed by the reduced diameter curved surface processing of the hollow billet has an outer diameter of 37mm, 38mm, 42mm or 39.2 mm.

4. A roll of steel pipe as claimed in claim 1 wherein the second steel pipe formed by said wall-reducing curved surface machining of said first steel pipe has an outer diameter of 31mm, 32mm, 33.4mm or 32.5 mm.

5. The roll for the steel pipe as claimed in claim 1, wherein the machining outer diameters of the 9 fourth pass section positioning lines are 27 to 30.69mm, 24 to 29.07mm, 23 to 27.45mm, 22.3 to 25.82mm, 19 to 24.2mm, 17.77 to 23.46mm, 17.15 to 22.72mm, 15.3 to 22.3mm and 15.1 to 22mm in this order.

6. The roll of steel pipe as claimed in claim 1, wherein the second steel pipe is finished to have an outer diameter of 15.1mm, 18mm, 22mm or 20.1mm by the sizing curve process.

7. A steel tube roll according to claim 1, characterized in that the roll body (10) is further provided with a feed opening (11) and a discharge opening (12).

8. A method for processing a steel pipe by using the steel pipe roll according to any one of claims 1 to 7, comprising:

heating a steel billet and then perforating to obtain a capillary, wherein the heating temperature is 1350 ℃ at most;

sequentially carrying out acid washing, phosphorization and saponification treatment on the tubular billet to obtain a tubular billet;

the steel pipe roll of any one of claims 1 to 7 is used for cold rolling a blank pipe to obtain a finished steel pipe, wherein the number of revolutions in the cold rolling process is 100 times/min, and the rolling elongation coefficient is 5.5.

9. The process of claim 8, wherein after obtaining the finished steel pipe, the process further comprises:

carrying out oil removal treatment on the finished steel pipe;

placing the finished steel pipe subjected to the oil removal treatment into an annealing furnace for high-temperature annealing treatment, and removing stress to obtain a seamless steel pipe;

and after the seamless steel pipe is cooled, carrying out acid pickling treatment, straightening treatment and eddy current flaw detection on the seamless steel pipe in sequence to obtain the qualified steel pipe.

10. The process of claim 8, wherein the acid wash treatment has a PH of from 1 to 2 and a treatment time of from 15 to 25 minutes;

the PH value of the phosphating treatment is between 2 and 3, and the treatment time is between 35 and 45 minutes;

the pH value of the saponification treatment is 10-11, the treatment time is 5, the pH value is 10-11 and 15 minutes, and the treatment temperature is kept between 60 ℃ and 70 ℃.

Technical Field

The invention belongs to the technical field of steel pipe processing, and particularly relates to a steel pipe roller and a steel pipe processing method.

Background

The steel pipe not only has the purposes of conveying fluid, powdery solid, exchanging heat energy, manufacturing mechanical parts and containers and the like, but also is an economic steel material, and products such as guns, bullets, missiles, rockets and the like used in national defense and aerospace can not be separated from daily appliances, furniture, water supply and drainage, air supply, ventilation and heating facilities of people to the manufacture of various agricultural machinery appliances, the development of underground resources; therefore, the steel pipe becomes one of the essential products in life and production of people.

At present, the production process of the steel pipe is to use a cold rolling mill to produce the steel pipe with low elongation coefficient, and after a semi-finished product of a middle pass is obtained, cold drawing production is carried out to finally obtain a finished steel pipe; however, the conventional steel pipe processing cannot produce small-caliber steel pipes (for example, steel pipes with calibers of 15mm, 20mm or 18 mm) at one time, and in order to manufacture the small-caliber steel pipes, multiple times of processing are required, and the smaller the calibers are, the more the processing times are; for example, in order to obtain a steel pipe of 20mm, a steel pipe of 25mm is processed into a steel pipe of 20mm by first processing a raw pipe into a steel pipe of 25mm and then cold-rolling and drawing the steel pipe; on the other hand, in order to obtain a 15mm steel pipe, cold rolling and drawing must be performed again on the basis of 20 mm.

Therefore, the above processing method has the following disadvantages: the efficiency is low, and the more intermediate passes, the more necessary processes are required (namely, the steel pipe with the diameter of 20mm is required to be processed, at present, two times of processing are required, namely, the hollow billet is processed into the steel pipe with the diameter of 25mm, and then the steel pipe with the diameter of 25mm is processed to the diameter of 15mm, so that the necessary processes such as acid washing, phosphorization, saponification and annealing are required to be performed at each processing time), and thus, the waste of resources, the increase of cost and more environmental pollution are caused; therefore, how to obtain the small-caliber steel pipe by one-time processing becomes a problem to be solved urgently.

Disclosure of Invention

The invention aims to provide a steel pipe roller and a steel pipe processing method, which aim to solve the problems of low efficiency, high cost and environmental pollution caused by the fact that multiple times of processing are needed to obtain a small-diameter steel pipe.

In order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides a steel pipe roller, comprising: the roller comprises a roller body, wherein a reducing groove, a wall reducing groove and a sizing groove are sequentially arranged on the roller body along the circumferential direction;

the reducing groove is provided with a first hole-type section positioning line and a second hole-type section positioning line, wherein the area of the reducing groove between the first hole-type section positioning line and the second hole-type section positioning line forms a reducing curved surface, and the outer diameter of a first steel pipe formed by machining a tubular billet through the reducing curved surface is between 37 and 42 mm;

a third hole type section positioning line is arranged on the wall-reducing groove, wherein a region of the wall-reducing groove between the second hole type section positioning line and the third hole type section positioning line forms a wall-reducing curved surface, and the outer diameter of a second steel pipe formed by machining the first steel pipe through the wall-reducing curved surface is between 31 and 33.4 mm;

the last edge of sizing groove the hollow billet processing direction has set gradually 9 fourth pass section location lines, wherein, the sizing groove is in the region between 9 fourth pass section location lines and constitutes the sizing curved surface, just the second steel pipe warp the external diameter of the finished product steel pipe that the processing of sizing curved surface formed is between 15.1 ~ 22 mm.

Based on the above disclosure, the present invention improves the roll for processing steel pipes, namely, changes the curvatures of three processing sections in the roll, which substantially comprises: changing the processing outer diameters of the first hole type section positioning line and the second hole type section positioning line, so as to change the curvature of the curved surface between the first hole type section positioning line and the second hole type section positioning line in the reducing groove (namely the outer diameter of the first steel pipe processed by the reducing curved surface represents that the processing outer diameter of the second hole type section positioning line is 37-42 mm, and the curvature of the curved surface formed by the two positioning lines can be determined after the processing outer diameters of the two positioning lines are determined); similarly, the processing outer diameters of the second hole type section positioning line and the third hole type section positioning line in the wall reducing groove and the processing outer diameters of the 9 fourth hole type section positioning lines are changed, and the curvatures of the wall reducing curved surface and the sizing curved surface can also be changed; therefore, the invention can obtain larger elongation coefficient, thereby obtaining the small-caliber steel pipe with the outer diameter of 15.1-22mm by one-time processing.

Through the design, the small-caliber steel pipe can be processed to a small-caliber steel pipe (for example, 15mm) at one time, so that the intermediate passes in the processing process of the small-caliber steel pipe are reduced, the necessary procedures such as acid washing, phosphorization, saponification and annealing are reduced, the waste of resources is reduced, the cost is reduced, and the environmental pollution is reduced.

In one possible design, the corresponding processing outer diameter of the first hole type section positioning line is 45 mm.

Based on the disclosure, the invention discloses the machining outer diameter of the first pass section positioning line, namely 45mm, namely, after the reducing curved surface is machined, the 45mm capillary can be directly machined into a 37-42 mm steel pipe, namely, after the machining outer diameters of the two positioning lines are determined, the curvature of the reducing curved surface can be determined.

In one possible design, the outer diameter of the first steel pipe formed by processing the tubular billet through the reducing curved surface is 37mm, 38mm, 42mm or 39.2 mm.

Based on the disclosure, the invention discloses specific parameters of the outer diameter of the first steel pipe, namely, equivalently disclosing the processing outer diameter corresponding to the second pass section positioning line; according to the parameters, the processing outer diameters of different sizes are combined with the first pass section positioning line to form reducing curved surfaces with different curvatures, so that the hollow billet can be processed into first steel pipes with different outer diameter sizes.

In one possible design, the outer diameter of the second steel pipe formed by the wall-reducing curved surface machining of the first steel pipe is 31mm, 32mm, 33.4mm or 32.5 mm.

Based on the above disclosure, the outer diameter of the second steel pipe represents the machined outer diameter of the third hole type section positioning line; therefore, the third hole type section positioning line with different processing outer diameters is combined with the second hole type section positioning line to form the wall-reducing curved surface with different curvatures, so that the first steel pipe can be processed into the second steel pipe with different outer diameter sizes.

In one possible design, the machining outer diameters of the 9 fourth hole type section positioning lines are 27-30.69 mm, 24-29.07 mm, 23-27.45 mm, 22.3-25.82 mm, 19-24.2 mm, 17.77-23.46 mm, 17.15-22.72 mm, 15.3-22.3 mm and 15.1-22mm in sequence.

Based on the disclosure, the invention discloses the machining outer diameter of each of the 9 fourth hole type section positioning lines, that is, by setting the 9 fourth hole type section positioning lines with different machining outer diameters, fixed diameter curved surfaces with different curvatures can be formed, so that the second steel pipe can be machined into finished steel pipes with different outer diameter sizes.

In one possible design, the outer diameter of the finished steel pipe formed by the sizing curve processing of the second steel pipe is 15.1mm, 18mm, 22mm or 20.1 mm.

Based on the disclosure, the roller provided by the invention can process the tubular billet into the steel pipe with the outer diameter of 15mm, 1mm, 18mm, 22mm or 20.1mm at one time, namely the invention can reduce the intermediate pass of processing the small-diameter steel pipe and further reduce the processing procedures.

In one possible design, the roller body is also provided with a feed inlet and a discharge outlet.

In a second aspect, the present invention provides a method for processing a steel pipe by using a steel pipe roll which may be designed according to any one of the first aspect and the first aspect, including:

heating a steel billet and then perforating to obtain a capillary, wherein the heating temperature is 1350 ℃ at most;

sequentially carrying out acid washing, phosphorization and saponification treatment on the tubular billet to obtain a tubular billet;

the steel pipe roll of any one of claims 1 to 7 is used for cold rolling a blank pipe to obtain a finished steel pipe, wherein the number of revolutions in the cold rolling process is 100 times/min, and the rolling elongation coefficient is 5.5.

Based on the disclosure, the invention can process the billet into the small-caliber steel pipe at one time, so that only one time of pickling, phosphating and saponification treatment is needed during cold rolling, and compared with the traditional processing method, the invention reduces the intermediate pass, thereby improving the processing efficiency, reducing the processing procedures, reducing the processing cost and reducing the pollution to the environment.

In one possible design, after obtaining the finished steel pipe, the method further includes:

carrying out oil removal treatment on the finished steel pipe;

placing the finished steel pipe subjected to the oil removal treatment into an annealing furnace for high-temperature annealing treatment, and removing stress to obtain a seamless steel pipe;

and after the seamless steel pipe is cooled, carrying out acid pickling treatment, straightening treatment and eddy current flaw detection on the seamless steel pipe in sequence to obtain the qualified steel pipe.

In one possible design, the pH value of the acid washing treatment is between 1 and 2, and the treatment time is between 15 and 25 minutes;

the PH value of the phosphating treatment is between 2 and 3, and the treatment time is between 35 and 45 minutes;

the pH value of the saponification treatment is 10-11, the treatment time is 5, the pH value is 10-11 and 15 minutes, and the treatment temperature is kept between 60 ℃ and 70 ℃.

Drawings

FIG. 1 is a schematic structural view of a diameter-reducing groove provided in the present invention;

FIG. 2 is a schematic structural view of a wall-reducing groove provided by the present invention;

FIG. 3 is a schematic structural view of a sizing groove provided in the present invention;

fig. 4 is a schematic diagram of the position structures of the first hole-type section positioning line, the second hole-type section positioning line, the third hole-type section positioning line and the fourth hole-type section positioning line in the roll body according to the present invention.

Fig. 5 is a sectional view of a roll body provided by the present invention.

FIG. 6 is a schematic flow chart showing the steps of the method for processing a steel pipe according to the present invention.

Reference numeral, 10-roller body; 20-reducing the diameter of the groove; 30-a wall reduction groove; 40-sizing grooves; 11-a feed inlet; 12-discharge hole.

Detailed Description

The invention is further described with reference to the following figures and specific embodiments. It should be noted that the description of the embodiments is provided to help understanding of the present invention, but the present invention is not limited thereto. Specific structural and functional details disclosed herein are merely illustrative of example embodiments of the invention. This invention may, however, be embodied in many alternate forms and should not be construed as limited to the embodiments set forth herein.

Examples

At present, the traditional steel pipe processing can not produce small-caliber steel pipes (such as steel pipes with calibers of 15mm, 20mm or 18mm and the like) at one time, and in order to manufacture the small-caliber steel pipes, multiple times of processing are needed, wherein the smaller the calibers are, the more the processing times are; for example, in order to obtain a steel pipe of 20mm, a steel pipe of 25mm is processed into a steel pipe of 20mm by first processing a raw pipe into a steel pipe of 25mm and then cold-rolling and drawing the steel pipe; and if a 15mm steel pipe is obtained, cold rolling and drawing are carried out again on the basis of 20 mm; this causes a lot of intermediate passes for processing the small-diameter steel pipe, thereby increasing the necessary processes of acid washing, phosphating, saponification, annealing and the like, resulting in lower processing efficiency, increased labor cost and environmental pollution; therefore, the embodiment provides a steel roll, which can process a steel billet into a small-diameter steel pipe at one time, so that multiple times of processing are not needed, intermediate passes are reduced, only one time of acid washing, phosphorization and saponification treatment is needed during cold rolling, the processing efficiency is improved, and the cost and the environmental pollution are reduced.

As shown in fig. 1 to 5, the steel tube roll provided in the first aspect of the present embodiment may include, but is not limited to, a roll body 10, wherein the roll body 10 is provided with a reducing groove 20, a wall reducing groove 30, and a sizing groove 40 in sequence along a circumferential direction.

That is, in this embodiment, the hollow billet is sequentially reduced in outer diameter through the reducing groove 20, then reduced in wall thickness through the wall reducing groove 30, and finally fixed in outer diameter through the sizing groove 40; and the steel pipe processed by the sizing groove 40 is a finished steel pipe.

As shown in fig. 5, in the present embodiment, for example, a feed port 11 and a discharge port 12 are provided on the roller body 10, so that the capillary is fed into the roller through the feed port 11, and is processed into a small-diameter steel pipe, and after the processing is completed, the small-diameter steel pipe is fed out from the discharge port 12; in the present embodiment, the inlet 11 is located on the diameter-reducing groove 20, and the outlet 12 is located on the diameter-fixing groove 40.

In this embodiment, the curvature of the curved surface in the three processing tanks is changed to process the hollow billet into a small-caliber steel pipe at one time, and the structure is changed as follows:

referring to fig. 4, in the present embodiment, a first hole-type section positioning line and a second hole-type section positioning line are disposed on the reducing groove 20, wherein a region of the reducing groove 20 between the first hole-type section positioning line and the second hole-type section positioning line forms a reducing curved surface; namely, the reducing curved surface is used for processing the tubular billet so as to reduce the outer diameter of the tubular billet.

In this embodiment, the outer diameter of the first steel pipe formed by processing the tubular billet through the reducing curved surface is between 37 and 42mm, that is, the processed outer diameter of the second hole-shaped cross-section positioning line is between 37 and 42mm, that is, the reducing curved surface can process the tubular billet into the first steel pipe with the outer diameter between 37 and 42 mm.

In the embodiment, the curvature of the reducing curved surface formed by the first hole-type section positioning line and the second hole-type section positioning line is changed by changing the processing outer diameters of the two; that is, in the present embodiment, the outer diameter of the first hole-shaped cross-section positioning line K is 45mm, and the outer diameter of the second hole-shaped cross-section positioning line B is 37-42 mm; therefore, as long as the processing outer diameters of the positioning lines K and B are determined, the curvature of the reducing curved surface formed between the positioning lines K and B is also determined, and the first steel pipes with different sizes and outer diameters can be produced.

In this embodiment, for example, the outer diameter of the first steel pipe formed by the reduced diameter curved surface processing of the tubular billet may be, but is not limited to, 37mm, 38mm, 42mm, or 39.2 mm; that is, the machining outer diameter of the second hole-type section positioning line B may be, but is not limited to, 37mm, 38mm, 42mm, or 39.2 mm.

As can be seen from the foregoing, since the machined outer diameter of the second hole-type section positioning line B is 4, the present embodiment can form reducing curves with 4 different curvatures, thereby obtaining first steel pipes with 4 different outer diameters.

Similarly, in the present embodiment, a third hole-type section positioning line is disposed on the reduced wall groove 30, wherein the reduced wall groove 30 forms a reduced wall curved surface in a region between the second hole-type section positioning line and the third hole-type section positioning line, and the outer diameter of the second steel pipe formed by machining the first steel pipe through the reduced wall curved surface is between 31mm and 33.4 mm.

That is, in the present embodiment, the machined outer diameter of the third hole-type section positioning line O is between 31 and 33.4mm, that is, the reduced wall curved surface formed between the second hole-type section positioning line B and the third hole-type section positioning line O can machine the first steel pipe into the second steel pipe with the outer diameter between 31 and 33.4 mm; the principle of changing the curvature of the wall-reducing curved surface is consistent with the principle, and the wall-reducing curved surface with different curvatures is obtained by setting different processing outer diameters of the second hole type section positioning line and the third hole type section positioning line.

In this embodiment, for example, the outer diameter of the second steel pipe formed by the first steel pipe through the wall-reducing curved surface machining may be, but is not limited to, 31mm, 32mm, 33.4mm, or 32.5 mm; that is, the machining outer diameter of the third hole type section positioning line can be, but is not limited to, 31mm, 32mm, 33.4mm or 32.5 mm.

Therefore, it can be seen from the above parameters that 4 kinds of reduced-wall curved surfaces with different curvatures can be formed between the second hole-type cross-section positioning line B and the third hole-type cross-section positioning line O; namely, a second hole type section positioning line B with the outer diameter of 39.2mm and a third hole type section positioning line 0 with the outer diameter of 32.5mm are respectively machined; machining a second hole type section positioning line B with the outer diameter of 42mm and a third hole type section positioning line 0 with the outer diameter of 33.4 mm; processing a second hole type section positioning line B with the outer diameter of 38mm and a third hole type section positioning line 0 with the outer diameter of 32 mm; and machining a second hole type section positioning line B with the outer diameter of 37mm and a third hole type section positioning line 0 with the outer diameter of 31 mm.

Similarly, since the conventional roll has 9 positioning lines in the sizing groove 40, in this embodiment, it is also necessary to provide 9 positioning lines and change the processing outer diameters of the 9 positioning lines, so as to obtain a sizing curved surface capable of directly producing a small-caliber steel pipe.

That is, in this embodiment, 9 fourth hole type section positioning lines are sequentially arranged on the sizing groove 40 along the tubular billet machining direction, wherein a region of the sizing groove 40 between the 9 fourth hole type section positioning lines forms a sizing curved surface, and the outer diameter of a finished steel pipe formed by the second steel pipe through the sizing curved surface machining is between 15.1mm and 22 mm.

Therefore, after the second steel pipe passes through the sizing curved surface, the outer diameter of the produced finished steel pipe is 15.1-22mm, namely the roller provided by the embodiment can be directly used for processing and producing the small-caliber steel pipe.

In this embodiment, for example, the machining outer diameters of the 9 fourth hole-type cross-section positioning lines are 27 to 30.69mm, 24 to 29.07mm, 23 to 27.45mm, 22.3 to 25.82mm, 19 to 24.2mm, 17.77 to 23.46mm, 17.15 to 22.72mm, 15.3 to 22.3mm and 15.1 to 22mm in sequence.

Namely, the machined outer diameters of two adjacent fourth pass section positioning lines are set, so that the curved surfaces formed between the two adjacent fourth pass section positioning lines have different curvatures, namely, 8 curved surfaces can be formed by 9 fourth pass section positioning lines, namely, after the second steel pipe is subjected to sizing through the 8 curved surfaces, the outer diameter can be directly reduced from 31-33.4 mm to 15.1-22mm, and the purpose of machining the second steel pipe into a small-caliber steel pipe at one time is achieved.

As shown in fig. 4, in this embodiment, for example, 9 fourth groove-shaped cross-section positioning lines are numbered sequentially from 1 to 9, that is, the machining outer diameter of the fourth groove-shaped cross-section positioning line 1 may be, but is not limited to: 27mm, 30.69mm, 29.25mm or 27.43 mm; for example, the machining outer diameter of the fourth hole-type section positioning line 2 can be, but is not limited to: 24mm, 29.07mm, 27.32mm or 25.63 mm; for example, the machining outer diameter of the fourth hole-type section positioning line 3 may be, but is not limited to: 23mm, 27.45mm, 25.2mm or 24.16 mm; for example, the machining outer diameter of the fourth hole-type section positioning line 4 may be, but is not limited to: 22.3mm, 25.82mm, 23.04mm, or 22.66 mm; for example, the machining outer diameter of the fourth hole-type section positioning line 5 can be, but is not limited to: 21.5mm, 24.2mm, 20.96mm or 19 mm; for example, the machining outer diameter of the fourth hole-type section positioning line 6 can be, but is not limited to: 21.22mm, 23.46mm, 20.06mm or 17.77 mm; for example, the machining outer diameter of the fourth hole-type section positioning line 7 may be, but is not limited to: 20.64mm, 22.72mm, 19.16mm or 17.15 mm; for example, the machining outer diameter of the fourth hole-type section positioning line 8 can be, but is not limited to: 20.3mm, 22.3mm, 18.3mm or 15.3 mm; for example, the machining outer diameter of the fourth hole-type section positioning line 9 can be, but is not limited to: 20.1mm, 22mm, 18mm or 15.1 mm.

Similarly, for example, the outer diameter of the finished steel pipe formed by the second steel pipe through the sizing curved surface machining may be, but is not limited to, 15.1mm, 18mm, 22mm, or 20.1mm, that is, the roller provided in this embodiment may be used to machine and produce a small-caliber steel pipe with an outer diameter of 15mm, 18mm, 22mm, or 20 mm.

As shown in table 1, table 1 shows the specific machining outer diameters of the four positioning lines to realize the production of the 4 kinds of small-caliber steel pipes.

TABLE 1

As can be seen from table 1, the roll provided in this embodiment can form a reduced-diameter curved surface, a reduced-wall curved surface, and a fixed-diameter curved surface with different curvatures by setting the machining outer diameters of the 12 hole-type cross-section positioning lines on the roll body 10, so as to implement one-time machining production of small-diameter steel pipes such as 20mm, 15mm, 18mm, and 22 mm; in this embodiment, the tolerance of the outer diameter and wall thickness of the steel pipe is within ± 0.05 mm.

Therefore, through the detailed description of the steel pipe roller, the invention can obtain the processing sections with different curvatures by changing the processing outer diameter of the hole-type section positioning line on the roller body 10, thereby obtaining a larger elongation coefficient, therefore, the invention can process the tubular billet to the small-caliber steel pipe at one time, thereby reducing the intermediate pass in the processing process of the small-caliber steel pipe, further reducing the necessary procedures of acid washing, phosphorization, saponification, annealing and the like, and reducing the waste of resources, the cost and the environmental pollution.

As shown in fig. 6, the second aspect of the present embodiment provides a method for processing a steel pipe by using the steel pipe rolling rolls according to the first aspect of the present embodiment, which may include, but is not limited to, the following steps S1 to S3.

S1, heating a steel billet and then perforating to obtain a capillary, wherein the maximum heating temperature is 1350 ℃.

In this embodiment, for example, but not limited to, a stepping furnace is used to heat the billet, the temperature is gradually raised to 1350 ℃, and the billet is perforated by a fully automatic 40 or 50 enhanced piercer to produce the hollow billet.

In this embodiment, the outer diameter and the wall thickness of the capillary can be, but are not limited to: 40mm 2.8mm to 45mm 3.5 mm.

After obtaining the hollow billet, for example, but not limited to, cutting off both ends of the hollow billet, and polishing end surfaces of both ends to make the end surfaces smooth, thereby preventing the end surfaces from being damaged due to burrs during cold rolling.

And (5) polishing the capillary tube to be smooth, and then performing step S2.

S2, carrying out acid washing, phosphorization and saponification treatment on the tubular billet in sequence to obtain a tubular billet.

The purpose of step S2 is: removing oxide skin and other impurities on the surface of the hollow billet; of course, in this embodiment, hydrochloric acid is used for example to acid-wash the hollow billet at normal temperature (25 ℃); for example, the pH value of the acid washing treatment is between 1 and 2, and the treatment time is between 15 and 25 minutes; for example, the pH value of the phosphating treatment is between 2 and 3, and the treatment time is between 35 and 45 minutes; for example, the saponification treatment has a pH of 10-11, a treatment time of 5 and a pH of 10-11, and a treatment temperature of 60-70 ℃.

After the tube blank is processed in step S2, the tube blank can be cold-rolled using the steel tube rolling roll of the first aspect, so as to be directly processed into a small-caliber finished steel tube, as shown in step S3.

And S3, performing cold rolling processing on the blank pipe by using the steel pipe roller in the first aspect of the embodiment to obtain a finished steel pipe.

In the embodiment, the feed inlet 11 of the steel tube roll is 2-3 mm larger than the external diameter of the hollow billet, the number of revolutions of the cold rolling process by using the two-roll cold rolling head is 100 times/min, the feed amount is not more than 3 mm/time, and the rolling elongation coefficient is 5.5.

Through the design, the steel pipe roller of the first aspect can be used for processing the steel billet into the small-caliber steel pipe at one time, so that only one-time acid washing, phosphorization and saponification treatment is needed during cold rolling, and compared with the traditional processing method, the method reduces the intermediate pass, further improves the processing efficiency, reduces the processing procedures, reduces the processing cost and reduces the pollution to the environment.

In this embodiment, after the finished steel pipe is obtained, the following steps may be performed to improve the quality of the finished steel pipe, as shown in steps S4 to S6.

And S4, carrying out oil removal treatment on the finished steel pipe.

In the present embodiment, the degreasing treatment is to put the finished steel pipe into a tank with degreaser added to soak for 30 minutes, and the soaking temperature is kept at 70 ℃.

And S5, placing the finished steel pipe subjected to the oil removal treatment into an annealing furnace for high-temperature annealing treatment, and removing stress to obtain the seamless steel pipe.

In this embodiment, the temperature of the high-temperature annealing treatment is 620-640 ℃ (preferably 630 ℃), the feeding speed of the finished steel tube into the annealing furnace is 1.8-2.2 m/min (preferably 2m/min), and the length of the heat preservation section in the annealing furnace is 38-43 m (preferably 40 m).

After the stress is removed, step S6 is performed.

And S6, after the seamless steel pipe is cooled, carrying out acid pickling treatment, straightening treatment and eddy current flaw detection on the seamless steel pipe in sequence to obtain the qualified steel pipe.

In this embodiment, the pickling is performed under the same pickling conditions as those in the foregoing step S2, and the straightening process may be, but is not limited to, a straightening machine, which has the function of eliminating the bend caused by the annealing; and the eddy current flaw detection is used for detecting the defects inside and outside the seamless steel pipe, so that the quality of the product is ensured, and the qualified product can be obtained after the detection is finished.

Finally, it should be noted that: the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.