CN111069335B

CN111069335B - Production method of embossed flat steel pipe

Info

Publication number: CN111069335B
Application number: CN201911336271.3A
Authority: CN
Inventors: 高银胜; 施利彪; 邢颢文
Original assignee: Jiangsu Tonglian Technology Co ltd
Current assignee: Suzhou Shengyu Automotive Parts Co.,Ltd.
Priority date: 2019-12-23
Filing date: 2019-12-23
Publication date: 2021-09-24
Anticipated expiration: 2039-12-23
Also published as: CN111069335A

Abstract

The invention discloses a production method of an embossed flat steel pipe, which comprises the following steps: the steel strip is opened a book, is planed the limit, knurling, return bend, welding and finishing shaping, its characterized in that, the knurling step includes two steps: firstly, pressing a required flower shape on the surface of the steel belt through an embossing die, and pressing convex ribs extending along the length direction of the steel belt on two sides of the flower shape through the embossing die while pressing the required flower shape; and then flattening the convex ribs. The invention can avoid the problem of extension deformation of the side edge of the steel strip in the embossing forming process of the steel strip, reduce the subsequent process steps, improve the efficiency and reduce the production cost.

Description

Production method of embossed flat steel pipe

Technical Field

The invention relates to a method for producing a steel pipe, in particular to a method for producing an embossed flat steel pipe.

Background

Fig. 1 shows a typical embossed flat steel pipe, in which a wall surface of the steel pipe is formed into a concavo-convex shape by extending the wall surface by die pressing. The production process of the embossed flat steel pipe comprises the steps of molding a steel belt to form a concave-convex shape, then axially bending the steel belt, welding the steel belt in the length direction to form the steel belt, and performing subsequent shaping and cutting to obtain a product meeting the requirements. In the production process, the extension amount of the steel strip is different at different concave-convex shape positions in the process of forming the concave-convex shape by die pressing, so that the side edge of the steel strip after the embossing is difficult to keep a linear state, and the difficulty is caused in subsequent bending welding. Therefore, in the prior art, an edge milling process is required to be added after embossing is finished, the side edge of the steel strip is milled and shaped to form a straight edge and meet the size requirement, and then the steel strip is bent and welded. Therefore, on one hand, the process steps are increased, the production efficiency is influenced, on the other hand, after the embossing is finished, a common plane tool cannot be used for clamping the steel belt edge milling, a special clamping tool corresponding to the embossing pattern shape is needed, the edge milling process can form steel belt waste, the steel belt needed for producing the same steel pipe is widened, and the production cost of the product is difficult to reduce.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a method for producing an embossed flat steel pipe, which solves the problem of extension deformation of the side edge of a steel belt in the steel belt embossing forming process. Another task of the invention is to provide an embossing combination production die for embossing flat steel pipes.

The technical scheme of the invention is as follows: a production method of an embossed flat steel pipe comprises the following steps: the method comprises the following steps of uncoiling a steel strip, planing an edge, embossing, bending the steel strip, welding and finishing, wherein the embossing step comprises two steps: firstly, pressing a required flower shape on the surface of the steel belt through an embossing die, and pressing convex ribs extending along the length direction of the steel belt on two sides of the flower shape through the embossing die while pressing the required flower shape; and then flattening the convex ribs.

Further, in order to better achieve the purpose of preventing the embossing, the steel strip is deformed to form a non-linear wave shape on the edge, the section of the convex rib is semicircular, and the convex height of the convex rib is smaller than that of the flower shape.

Further, the gap between the convex rib and the edge of the flower shape is 3% -5% of the width of the flower shape.

Further, the width of the convex rib is 6% -10% of the width of the flower shape.

Further, the flattening of the convex ribs is performed in a rolling manner.

Compared with the prior art, the invention has the advantages that: set up protruding muscle through the both sides in flower shape region, and protruding muscle is shaping in the decorative pattern shaping, the steel band extension volume that the size differs that makes the decorative pattern position produce absorbs along protruding muscle length direction in protruding muscle position and eliminates, block its stretching to the steel band both sides, make the steel band both sides along keeping the linear state, follow-up protruding muscle that flattens through the rolling die, this makes the steel band that the knurling was accomplished no longer need mill the limit and can directly carry out the bending weld, the process steps that has been reduced raises the efficiency, the development of material loss and centre gripping mould has also been reduced, steel pipe manufacturing cost has been reduced.

Drawings

Fig. 1 is a schematic structural view of an embossed flat steel pipe.

FIG. 2 is a partial schematic view of the edge of a prior art steel strip after embossing the surface.

Fig. 3 is a schematic top view of a bottom die of the method for producing an embossed flat steel pipe.

Fig. 4 is a schematic side sectional view of the bottom die of the method for producing an embossed flat steel pipe.

Fig. 5 is a schematic side sectional view of an upper die of the method for producing an embossed flat steel pipe.

Fig. 6 is a schematic view of an embossing combined production die for embossing flat steel pipes.

Detailed Description

The present invention is further illustrated by the following examples, which are not to be construed as limiting the invention thereto.

The production method of the embossed flat steel pipe related to the embodiment comprises the following steps: the method comprises the following steps of uncoiling a steel strip, planing an edge, embossing, bending the steel strip, welding and finishing, wherein the embossing step comprises two steps: firstly, pressing a required flower shape on the surface of a steel strip through an embossing die, and pressing convex ribs with semicircular sections extending along the length direction of the steel strip on two sides of the flower shape through the embossing die while pressing the required flower shape; and then flattening the convex ribs in a rolling manner. The protruding height of the convex rib is less than that of the flower shape, the gap between the convex rib and the edge of the flower shape is 3% -5% of the width of the flower shape, and the width of the convex rib is 6% -10% of the width of the flower shape.

The embossing die adopted by the invention comprises a bottom die 1 and an upper die 2, wherein the bottom die 1 is generally a fixed die, the upper die 2 is a movable die, and corresponding patterns are formed on the surface of a steel strip through concave-convex textures on the surface when the upper die 2 and the bottom die 1 are closed. Due to the lack of control over the sides of the strip 3, the strip extension formed by the embossing is directly reflected on the sides of the strip 3 after the surface embossing of the strip 3, as shown in fig. 2, so that the strip edges 3a cannot remain flush.

As shown in fig. 3 to 5, the bottom mold 1 and the upper mold 2 are respectively provided with pattern pits 4 and pattern protrusions 5 for forming the steel pipe pattern, in this embodiment, the pattern pits 4 are provided on the surface of the bottom mold 1, and the pattern protrusions 5 are provided on the surface of the upper mold 2. The pattern pits 4 and the pattern protrusions 5 are correspondingly arranged up and down, and the positions of the pattern pits 4 and the pattern protrusions 5 are an embossing area A. Since the patterns of the embossed regions A are different in the longitudinal direction of the steel strip, the extending amounts of the steel strip to both sides in the embossing process are also different in the longitudinal direction, in order to eliminate the uneven edge caused by the non-uniform extending amounts. In this embodiment, the bottom die 1 and the upper die 2 are respectively provided with a groove 6 and a protruding strip 7 extending along the length direction at two sides of the embossing area a, specifically, the bottom die 1 is provided with the groove 6, and the upper die 2 is provided with the protruding strip 7. The grooves 6 and the convex strips 7 are arranged correspondingly up and down, and when the upper die 2 and the bottom die 1 are closed, the steel strip forms patterns and simultaneously forms the convex strips extending in the length direction on two sides of the patterns. In order to ensure the surface quality of the finished steel pipe and facilitate the subsequent flattening step, the groove 6 is an arc-shaped groove 6, chamfers are arranged on two sides of the arc-shaped groove 6, and the shape of the convex strip 7 corresponds to that of the groove 6. The gap between the groove 6 and the edge of the embossed region a is set to 3% to 5%, preferably 3% of the width of the embossed region a, and the width of the groove 6 is 6% to 10%, preferably 7% of the width of the embossed region a. This width and clearance set up and have guaranteed that fashioned flower shape can not receive protruding muscle influence and warp and can effectively prevent the irregular extension at steel band border again simultaneously, consequently accomplish the steel band edge of knurling and still can keep the straight line state of flushing.

As shown in fig. 6, in the whole process of manufacturing the embossed flat steel tube, a rolling mold is needed to be disposed at the subsequent stage of the manufacturing method of the embossed flat steel tube to flatten the convex rib, and only the embossed shape is left for bending and welding. The embossing die and the rolling die are combined to form an embossing combined production die for embossing the flat steel pipe. The rolling die comprises an upper rolling wheel 8 and a lower rolling wheel 9, the upper rolling wheel 8 and the lower rolling wheel 9 are arranged in a vertically corresponding mode, the surfaces of the upper rolling wheel 8 and the lower rolling wheel 9 are both planes, and the upper rolling wheel 8 and the lower rolling wheel 9 are located on the length extension lines of the grooves 6 and the convex strips 7 and are used for flattening the convex ribs. When the embossed steel strip enters between the upper rolling wheel 8 and the lower rolling wheel 9, the convex ribs are expanded and flattened through the rolling of the upper rolling wheel 8 and the lower rolling wheel 9, and the deformation of the convex ribs in the length direction of the steel strip is consistent all the time, so that the edge of the steel strip is still kept in a flush straight line state after being flattened.

Claims

1. A production method of an embossed flat steel pipe comprises the following steps: the steel strip is opened a book, is planed the limit, knurling, return bend, welding and finishing shaping, its characterized in that, the knurling step includes two steps: firstly, pressing a required flower shape on the surface of the steel belt through an embossing die, pressing convex ribs extending along the length direction of the steel belt on two sides of the flower shape through the embossing die while pressing the required flower shape, wherein the gap between each convex rib and the edge of the flower shape is 3% -5% of the width of the flower shape, and the width of each convex rib is 6% -10% of the width of the flower shape; and then flattening the convex ribs.

2. The method for producing an embossed flat steel pipe as claimed in claim 1, wherein the ribs have a semicircular cross section, and the ribs have a smaller height than the flower shape.

3. The method of claim 1, wherein the flattening is performed by rolling.