阅读说明：本技术 一种双壁螺旋焊管及其制造方法 (Double-wall spiral welded pipe and manufacturing method thereof ) 是由 战福军 于 2021-08-06 设计创作，主要内容包括：本发明公开了一种双壁螺旋焊管,由双层复合钢带螺旋状卷焊形成；所述双层复合钢带包括等宽平行对齐设置的第一钢带层和第二钢带层,所述第一钢带层和第二钢带层之间设有至少两条与之垂直的支撑钢条,所述支撑钢条在第一钢带层和第二钢带层的两侧端部设置并与之共同延伸排布,所述第一钢带层、第二钢带层以及两侧端部的支撑钢条相互焊接形成延伸方向截面为矩形的双层复合钢带。还公开了该双壁螺旋焊管的制造方法。本发明设计的双壁螺旋焊管结构强度高,在满足钢管现有国家标准的外压及内压强度的前提下,可极大的节省材料用量,降低成本；在焊接边设计焊接坡口,可使焊接处更为稳固,同时由于是坡口,焊缝焊接后,管壁更为平滑,利于顶管施工。(The invention discloses a double-wall spiral welded pipe, which is formed by spirally welding double-layer composite steel strips; the double-layer composite steel belt comprises a first steel belt layer and a second steel belt layer which are arranged in parallel in an aligned mode and have equal width, at least two supporting steel bars perpendicular to the first steel belt layer and the second steel belt layer are arranged between the first steel belt layer and the second steel belt layer, the supporting steel bars are arranged at the end portions of the two sides of the first steel belt layer and the second steel belt layer and extend together with the first steel belt layer and the second steel belt layer, and the first steel belt layer, the second steel belt layer and the supporting steel bars at the end portions of the two sides are welded with each other to form the double-layer composite steel belt with rectangular cross sections in the extending direction. A method of making the double-walled helically welded tube is also disclosed. The double-wall spiral welded pipe designed by the invention has high structural strength, and can greatly save the material consumption and reduce the cost on the premise of meeting the external pressure and internal pressure strength of the existing national standard of steel pipes; the welding groove is designed on the welding edge, so that the welding position is more stable, and meanwhile, due to the groove, the pipe wall is smoother after the welding seam is welded, and the pipe jacking construction is facilitated.)

1. A double-walled spiral welded pipe characterized in that: formed by spirally welding a double-layer composite steel strip; the double-layer composite steel belt comprises a first steel belt layer (1) and a second steel belt layer (2) which are aligned in parallel and arranged in an equal-width mode, at least two supporting steel bars (3) perpendicular to the first steel belt layer (1) and the second steel belt layer (2) are arranged between the first steel belt layer (1) and the second steel belt layer (2), the supporting steel bars (3) are arranged at the end portions of the two sides of the first steel belt layer (1) and the second steel belt layer (2) and are arranged in a co-extending mode, and the first steel belt layer (1), the second steel belt layer (2) and the supporting steel bars (3) at the end portions of the two sides are welded with each other to form the double-layer composite steel belt with rectangular cross sections in the extending direction.

2. The double-walled helically welded tube of claim 1, wherein: after the supporting steel strips (3) are arranged at the end parts of the two sides of the first steel strip layer (1) and the second steel strip layer (2), the steel strip layer protrudes out of the outer side edge of the supporting steel strips (3), and when the double-layer composite steel strip is in coil welding, the protruding parts of the supporting steel strips (3) on the two sides are spliced and form a welding groove (4) with the steel strip layer.

3. The double-walled helically welded tube of claim 1, wherein: support billet (3) of steel tape both sides between the interval simultaneously be equipped with many support billet (3), support first steel tape layer (1) and second steel tape layer (2) inside, all support billet (3) are parallel to each other and extend jointly and arrange.

4. The double-walled helically welded tube of claim 1, wherein: the first steel belt layer (1) is formed by a plurality of split steel belts (101) in parallel arrangement and welding, and the joints of the adjacent split steel belts (101) correspond to a supporting steel bar (3).

5. The double-walled helically welded tube of claim 4, wherein: when the double-layer composite steel strip is subjected to coil welding, the first steel strip layer (1) is positioned on the outer wall of the pipeline.

6. A method of manufacturing a double-walled helically welded tube according to claim 1, comprising the steps of:

s1, discharging a second steel strip from the steel coil, and horizontally placing to form a second steel strip layer (2);

s2, paying out supporting steel bars (3) from a plurality of vertical steel coils, placing the supporting steel bars perpendicular to the second steel belt layer (2), wherein two supporting steel bars are placed at the end part of the side edge of the second steel belt layer (2), and the bottom of each supporting steel bar (3) is welded with the second steel belt layer (2);

s3, a first steel strip with the same width as the second steel strip is paid out from the steel coil, and the first steel strip and the second steel strip are horizontally placed on the support steel strip (3) correspondingly to form a first steel strip layer (1) and are welded and fixed to form a double-layer composite steel strip;

s4, spirally bending and rolling the double-layer composite steel strip by using spiral steel welded pipe processing equipment, continuously welding the inner and outer welding seams of the pipe, and continuously forming the steel pipe.

7. The method of manufacturing a double-walled helically welded pipe according to claim 6, wherein: s2, the steel belt layer protrudes out of the outer side of the supporting steel bar (3) at the end part of the side edge of the second steel belt layer (2), S4 when the steel belt is rolled, when the steel belt is rolled to complete a circle of track, when the steel belt is contacted with the edge of the steel belt which is not rolled, two welding grooves (4) at the inner part and the outer part of the pipe can be formed, and the contacted supporting steel bar (3) and the adjacent steel belt layer are welded and fixed through the welding grooves (4).

8. The method of manufacturing a double-walled helically welded pipe according to claim 7, wherein: and continuously rolling the steel belt from bottom to top, welding the inner welding groove and the outer welding groove of the pipe at the same position (4), and continuously welding and fixing the outer welding groove of the pipe above the pipe.

9. The method of manufacturing a double-walled helically welded pipe according to claim 6, wherein: the first steel belt layer (1) in the S3 comprises a plurality of split steel belts (101) which are arranged in parallel, the split steel belts are respectively placed on the supporting steel bars (3) by steel coil paying off, seams of the adjacent split steel belts (101) correspond to the supporting steel bars (3) to form welding seams, and the three are welded and fixed through the welding seams.

Technical Field

The invention relates to the technical field of steel pipe welding, in particular to a double-wall spiral welded pipe and a manufacturing method thereof.

Background

Most of the existing spiral welded steel pipes are single-layer pipe walls, when the caliber of the steel pipe is required to be more than 2 meters, in order to meet the requirements of water pressure in the steel pipe and external load of the steel pipe, the thickness of the pipe wall is about 20 millimeters, and the steel consumption is large; when the diameter of the pipeline is required to be about 3 meters, the thickness of the steel pipe needs to be about 30 millimeters. In this case: the steel consumption is large, and the manufacturing cost is high; the steel plate with the thickness of 30 millimeters is a rectangular blocky flat plate in the delivery state of a steel mill, delivery can not be carried out in a steel coil or steel strip state, the continuous coiling and continuous welding of the production line type of the spiral welded pipe can not be met, the rectangular blocky steel plate can only be singly pre-bent and coiled into a cylinder shape, a straight welding line is welded, a unit section straight welded pipe with short length is manufactured, then each unit section is butt-welded, and the production efficiency is greatly reduced. In addition, the ability of the weld joint of the straight welded pipe to bear the internal pressure is weaker than that of the spiral welded pipe, and the wall thickness is usually 10% -25% thicker than that of the spiral welded pipe, so that the manufacturing cost is increased. Furthermore, when the diameter of the spiral welded pipe of a single wall reaches about 2.5 m, the capacity of bearing external load is obviously reduced, and even when the pipe is placed in a free state, the pipe is deformed in an oval shape under the self weight of the pipe, and a temporary support in a shape like a Chinese character 'mi' is required to be arranged in the pipe.

Disclosure of Invention

The purpose of the invention is as follows: in order to overcome the defects of the background art, the invention discloses a double-wall spiral welded pipe; the second purpose is to disclose the manufacturing method of the double-wall spiral welded pipe.

The technical scheme is as follows: the double-wall spiral welded pipe disclosed by the invention is formed by spirally welding double-layer composite steel strips; the double-layer composite steel belt comprises a first steel belt layer and a second steel belt layer which are arranged in parallel in an aligned mode and have equal width, at least two supporting steel bars perpendicular to the first steel belt layer and the second steel belt layer are arranged between the first steel belt layer and the second steel belt layer, the supporting steel bars are arranged at the end portions of the two sides of the first steel belt layer and the second steel belt layer and extend together with the first steel belt layer and the second steel belt layer, and the first steel belt layer, the second steel belt layer and the supporting steel bars at the end portions of the two sides are welded with each other to form the double-layer composite steel belt with rectangular cross sections in the extending direction.

Furthermore, after the support steel bars are arranged at the end parts of the two sides of the first steel belt layer and the second steel belt layer, the steel belt layer protrudes out of the outer side edges of the support steel bars, and when the double-layer composite steel belt is in coil welding, the protruding parts of the support steel bars on the two sides are spliced to form a welding groove with the steel belt layer.

The support steel bars and the adjacent steel belt layers which are in contact with each other can be welded together through the welding groove, and the smooth pipe wall after welding can be achieved.

Further, the interval is equipped with many support billet simultaneously between the support billet of steel strip both sides, supports first steel strip layer and second steel strip in situ portion, and all support billets are parallel to each other and extend jointly and arrange.

Furthermore, the first steel belt layer is formed by a plurality of split steel belts which are arranged in parallel and welded, and the joints of the adjacent split steel belts correspond to a supporting steel bar.

When the joint of the adjacent split steel belts is welded, the split steel belts can be welded with the corresponding support steel bars at the same time, so that the three parts are fixed, and the structure is more stable.

Meanwhile, due to the fact that welding seams exist among the split steel strips, continuous spiral welding seams are formed when the split steel strips are rolled into a pipeline, the spiral welding seams are not beneficial to water flow to pass through quickly, and therefore when the double-layer composite steel strips are rolled and welded, the first steel strip layer is located on the outer wall of the pipeline, and the spiral welding seams are located on the outer wall of the pipeline.

The manufacturing method of the double-wall spiral welded pipe comprises the following steps:

s1, discharging a second steel strip from the steel coil, and horizontally placing to form a second steel strip layer;

s2, paying out supporting steel bars from the plurality of vertical steel coils, placing the supporting steel bars perpendicular to the second steel belt layer, wherein two supporting steel bars are placed at the end part of the side edge of the second steel belt layer, and the bottom of each supporting steel bar is welded with the second steel belt layer;

s3, a first steel strip with the same width as the second steel strip is paid out from the steel coil, and the first steel strip and the second steel strip are horizontally placed on the support steel strip correspondingly to form a first steel strip layer and are welded and fixed to form a double-layer composite steel strip;

s4, spirally bending and rolling the double-layer composite steel strip by using spiral steel welded pipe processing equipment, continuously welding the inner and outer welding seams of the pipe, and continuously forming the steel pipe.

The steel belt layer is arranged at the end part of the side edge of the second steel belt layer in the S2, the steel belt layer protrudes from the outer side of the supporting steel belt, the S4 can form two welding grooves inside and outside the pipe when the steel belt is rolled to complete a circle of track and is contacted with the edge of the steel belt which is not rolled, and the contacted supporting steel belt and the adjacent steel belt layer are welded and fixed through the welding grooves.

Further, the steel belt is continuously rolled from bottom to top, and for the inner and outer welding grooves at the same position, the inner welding groove of the pipe is firstly welded, and then the outer welding groove of the pipe is welded above the pipe, so that the steel belt is continuously welded and fixed.

Furthermore, the first steel belt layer in the S3 includes a plurality of split steel belts arranged in parallel, the split steel belts are respectively paid out from a steel coil and placed on the supporting steel bars, seams of the adjacent split steel belts correspond to one supporting steel bar, a welding seam is formed, and the split steel belts, the supporting steel bars and the adjacent split steel belts are welded and fixed through the welding seam.

Has the advantages that: compared with the prior art, the invention has the advantages that:

1. the double-wall spiral welded pipe designed by the invention has high structural strength, and can greatly save the material consumption and reduce the cost on the premise of meeting the external pressure and internal pressure strength of the existing national standard of steel pipes;

2. the welding groove is designed on the welding edge, so that the welding position is more stable, and meanwhile, due to the groove, the pipe wall is smoother after the welding seam is welded, thereby being beneficial to pipe jacking construction;

3. the whole body adopts a split splicing welding mode, so that the split welding can be carried out, and the problems that steel pipes with the diameter of more than 3 meters cannot be delivered in a roll shape due to too thick steel plate materials, only can be delivered in a plate shape, and the spiral welded pipes cannot be continuously produced are solved; meanwhile, the inner and outer steel plates can be independently used or all made of stainless steel or made of stainless steel composite steel, so that the durability of the steel pipe is improved, the service life of the steel pipe is greatly prolonged, and the manufacturing cost is not increased or only slightly increased;

4. the supporting steel bars support the integral pipe wall, so that concrete can be filled in a cavity between the inner layer and the outer layer to increase the structural strength and prevent internal corrosion;

5. on the premise of achieving the same structural strength, the pipeline has the advantages of reducing the weight, reducing the construction and hoisting cost, simultaneously being longer in length of a single section, and reducing the pipe section welding seams in a construction site.

Drawings

FIG. 1 is a schematic view of a double-walled spiral welded pipe according to the present invention;

FIG. 2 is a sectional view of the double-layered composite steel strip according to the present invention in the direction of elongation;

FIG. 3 is a view showing a structure of a welding groove of the present invention;

FIG. 4 is a cross-sectional view of the inner support steel strip of the double-layered composite steel strip according to the present invention;

FIG. 5 is a structural view of a split steel strip of a double-layer composite steel strip according to the present invention;

FIG. 6 is a flow chart of the present invention.

Detailed Description

The invention is described in further detail below with reference to the figures and the detailed description.

The double-walled spiral welded pipe shown in fig. 1 is formed by spirally roll-welding double-layer composite steel strips.

As shown in fig. 2, the double-layer composite steel strip comprises a first steel strip layer 1 and a second steel strip layer 2 which are aligned in parallel and have equal widths and are extended together. Two support steel strips 3 perpendicular to the first steel strip layer 1 and the second steel strip layer 2 are arranged between the first steel strip layer 1 and the second steel strip layer 2, the support steel strips 3 are arranged at the end parts of the two sides of the first steel strip layer 1 and the second steel strip layer 2 and extend together with the first steel strip layer 1 and the second steel strip layer 2, the steel strip layers protrude out of the outer side edges of the support steel strips 3 when the support steel strips are arranged, and the first steel strip layer 1, the second steel strip layer 2 and the support steel strips 3 at the end parts of the two sides are welded with each other to form a double-layer composite steel strip with a rectangular section in the extending direction.

As shown in fig. 3, when the double-layer composite steel strip is coil-welded, the protruding portions of the support steel strips 3 on both sides are spliced to form a welding groove 4 with the steel strip layer, and when the welding groove 4 is welded, the two support steel strips 3 to be spliced and the four adjacent steel strip layers are welded and fixed at the same time, and the welding seam is relatively flat with respect to the pipe wall.

As shown in fig. 4, after the supporting steel strips 3 are disposed at the end portions of both sides of the first steel strip layer 1 and the second steel strip layer 2, two supporting steel strips 3 are disposed between the supporting steel strips 3 at both sides at an interval, so as to support the inside of the first steel strip layer 1 and the second steel strip layer 2, and all the supporting steel strips 3 are mutually parallel and arranged in a co-extending manner, and are integrally welded and fixed.

As shown in fig. 5, in consideration of the inconvenience of welding a plurality of support steel strips 3 and steel strip layers inside, the first steel strip layer 1 is designed to be formed by welding three separate steel strips 101 in parallel, and the joints of the adjacent separate steel strips 101 correspond to one support steel strip 3. Each adjacent split steel belt 101 and the corresponding support steel bar 3 form a welding line, so that the three components can be welded and fixed conveniently. In order to avoid that the continuous welding seam has adverse effect on the drainage, when the double-layer composite steel strip is coiled and welded, the first steel strip layer 1 is positioned on the outer wall of the pipeline, so that the welding seam is generated on the outer wall of the pipeline.

As shown in fig. 6, the method for manufacturing the double-walled spirally welded pipe comprises the following steps:

s1, discharging a second steel strip from the steel coil, and horizontally placing to form a second steel strip layer 2;

s2, paying out supporting steel bars 3 from the four vertical steel coils, placing the supporting steel bars perpendicular to the second steel belt layer 2, wherein two of the supporting steel bars are placed at the end part of the side edge of the second steel belt layer 2 and protrude out of the steel belt layer, the other two supporting steel bars are placed in the middle, and the bottom of each supporting steel bar 3 is welded with the second steel belt layer 2;

s3, a first steel strip with the same width as that of a second steel strip is paid out from the steel coil and is horizontally placed on the support steel strip 3 corresponding to the second steel strip to form a first steel strip layer 1, the first steel strip layer 1 comprises three split steel strips 101 which are arranged in parallel, the split steel strips are paid out from the steel coil and are placed on the support steel strip 3, seams of the adjacent split steel strips 101 correspond to one support steel strip 3 to form welding seams, and the three are welded and fixed through the welding seams to form a double-layer composite steel strip;

s4, the double-layer composite steel strip is coiled by spiral steel welding pipe processing equipment in a spiral bending mode, during coiling, a first steel belt layer 1 is an outer ring, when the steel belt is coiled to complete a circle of track, when the steel belt is contacted with the edge of a steel belt which is not coiled, two welding grooves 4 are formed inside and outside the pipe by the contact of support steel bars 3 on two sides, the support steel bars 3 which are contacted are welded and fixed with the adjacent steel belt layer through the welding grooves 4, the steel belt is coiled continuously from bottom to top, the welding grooves 4 inside and outside the same position are welded on the pipe inner welding groove, the welding grooves outside the pipe are welded on the upper portion of the pipe, the welding is fixed continuously, and the steel pipe is formed continuously.