CN113953316A - Rolling method for rolling 310Z-shaped steel by using flat billet with thickness of less than 110mm - Google Patents

Abstract

The invention discloses a rolling method for rolling 310Z-shaped steel by using a flat billet with the thickness of less than 110mm, wherein a thin billet with the thickness of less than 110mm enters a first special-shaped deep cutting hole pattern after being subjected to width setting; the transition hole pattern at the beginning of the second special-shaped hole pattern adopts a butterfly hole pattern structure, the hole pattern height H2 is more than H1, and the transition is gradually carried out to the H3 of the forming hole pattern; the forming hole type also adopts a butterfly hole type structure, but the vertex of the corner and the central point of the leg arc are fixed at four points, or the intersection point of the leg long arc and the horizontal line segment is increased to form a six-point fixed hole type basic structure; and the last hole is a finished hole, the height H of the hole is more than or equal to H3, the bent leg is straightened, and the thickness, the size and the shape are regulated to form the qualified B-shaped steel. The method can reduce the heating time of the casting blank and the surface burning loss rate, well control the swing of the rolled piece in the guide device, improve the dimensional precision of the 310Z-shaped steel and improve the yield of products.

Description

Rolling method for rolling 310Z-shaped steel by using flat billet with thickness of less than 110mm

Technical Field

The invention relates to the technical field of material steel rolling, in particular to a rolling method for rolling 310Z-shaped steel by using a flat billet with the thickness of less than 110 mm.

Background

The 310B-shaped steel belongs to special-shaped section steel, is mainly used for manufacturing railway vehicles, has a complex section, is named after the shape of the B, consists of long legs, short legs and waists, and is characterized in that the long legs are long and thin, the short legs are short and thick, the waists are thin and high, the difference of the three parts is huge, the uneven deformation is extremely serious in the rolling process, the product is a section steel product which is difficult to develop, and the rolling difficulty is also large; at the same time, the requirements on the pore type design are also high.

The traditional 310B-shaped steel production process adopts blanks with the thickness of more than 160mm, performs cogging by rolling five passes in 2 deep cutting passes, and then performs rolling by passes to produce finished products. Each hole type is provided with a fixed angular point and a fixed circle center, and the corner is ensured to be filled through the thicker blank thickness.

As shown in fig. 3:

the production process of the 310B-shaped steel adopts blanks with the thickness of more than 160mm, the section size of the blanks is large, the heating procedure time is long, and the contradiction exists between the control of the internal and external temperature difference and the control of the oxidation burning loss.

The cogging procedure has many passes, the guide control function is not obvious, the size fluctuation of the head and the tail is large, the cutting loss is influenced, and the yield is not favorably improved.

Disclosure of Invention

In order to solve the technical problems, the invention aims to provide a rolling method for rolling 310B steel by using a flat billet with the thickness of less than 110 mm.

In order to solve the technical problems, the invention adopts the following technical scheme:

the invention relates to a rolling method for rolling 310Z-shaped steel by using a flat billet with the thickness of less than 110mm, which comprises the following steps:

a thin blank with the thickness of less than 110mm is used and enters a first special-shaped deep cutting hole pattern after being subjected to width setting; the transition hole pattern at the beginning of the second special-shaped hole pattern adopts a butterfly hole pattern structure, the hole pattern height H2 is more than H1, and the transition is gradually carried out to the H3 of the forming hole pattern; the forming hole type also adopts a butterfly hole type structure, but the vertex of the corner and the central point of the leg arc are fixed at four points, or the intersection point of the leg long arc and the horizontal line segment is increased to form a six-point fixed hole type basic structure; the last hole is a finished hole, the height H of the hole is more than or equal to H3, the bent leg is straightened, and the thickness, the size and the shape are regulated to form qualified B-shaped steel;

the production is carried out by using a flat blank with the thickness of less than 110mm, the first hole adopts a structure with a small inclination angle of less than 30 degrees and a low hole height of less than 190mm, and the leg waist included angle is an obtuse angle and is used as the transition between the blank and a subsequent forming hole pattern, so that the use of the thin blank becomes possible; and increasing the inclination angle of the subsequent pass, fixing the positions of the angular points and the circle center after the target pass height is reached, reducing the leg thickness, filling the angular parts, and realizing the stable production of the Z-shaped steel.

Compared with the prior art, the invention has the beneficial technical effects that:

the heating time of the casting blank is reduced by more than 30min, and the surface burning loss rate is reduced by more than 0.5 percent.

The rolled piece is well controlled to swing in the guide device, the size fluctuation of the 310Z-shaped steel is improved within 1.5mm, and the product yield is improved by more than 1%.

The flexibility of selecting the size of the 310B-shaped steel casting blank is increased, the smooth production can be organized, and the contract response rate is improved.

Drawings

The invention is further illustrated in the following description with reference to the drawings.

FIG. 1 is a schematic view of a hole pattern of a 110mm flat blank;

FIG. 2 is a photograph of a 110mm flat rolled 310B-steel material;

FIG. 3 is a schematic diagram of a prior art pass.

Detailed Description

As shown in fig. 1, a rolling method for rolling 310 b steel by using a 110mm below flat billet comprises the following steps:

the production process of rolling 310B-shaped steel by adopting a flat billet with the thickness of less than 110mm comprises the following steps:

280mm 380mm continuous casting billet-heating furnace-high pressure water dephosphorization-BD 1 cogging-BD 2 cogging-CCS rolling-cooling-straightening-saw cutting-bundling-warehousing;

rolling a continuous casting billet with the thickness of 280mm multiplied by 380mm into a flat billet with the thickness of 110mm by means of BD1 cogging rolling;

a thin blank with the thickness of less than 110mm is used, and enters a first special-shaped deep cutting hole type H1 after being subjected to width setting;

the transition hole pattern at the beginning of the second special-shaped hole pattern adopts a butterfly hole pattern structure, and the hole pattern height H2 is more than H1;

h3 gradually transited to a forming pass through rolling;

the forming hole type also adopts a butterfly hole type structure, but the vertex of the corner and the central point of the leg arc are fixed at four points, or the intersection point of the leg long arc and the horizontal line segment is increased to form a six-point fixed hole type basic structure;

and the last hole is a finished hole, the height H of the hole is more than or equal to H3, the bent leg is straightened, and the thickness, the size and the shape are regulated to form the qualified B-shaped steel.

The production is carried out by adopting a 110 flat blank, the first hole adopts a structure with a small inclination angle below 30 degrees and a low hole height below 190mm, and the leg-waist included angle is an obtuse angle and is used as the transition between the blank and a subsequent forming hole pattern, so that the use of the thin blank becomes possible; and increasing the inclination angle of the subsequent pass, fixing the angular points and the circle center position (four-point fixation or six-point fixation) after the target pass height is reached, reducing the leg thickness, filling the corners, and realizing the stable production of the Z-shaped steel.

The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.

Claims (1)

1. A rolling method for rolling 310B-shaped steel by using a flat billet with the thickness of less than 110mm is characterized by comprising the following steps:

a thin blank with the thickness of less than 110mm is used and enters a first special-shaped deep cutting hole pattern after being subjected to width setting; the transition hole pattern at the beginning of the second special-shaped hole pattern adopts a butterfly hole pattern structure, the hole pattern height H2 is more than H1, and the transition is gradually carried out to the H3 of the forming hole pattern; the forming hole type also adopts a butterfly hole type structure, but the vertex of the corner and the central point of the leg arc are fixed at four points, or the intersection point of the leg long arc and the horizontal line segment is increased to form a six-point fixed hole type basic structure; the last hole is a finished hole, the height H of the hole is more than or equal to H3, the bent leg is straightened, and the thickness, the size and the shape are regulated to form qualified B-shaped steel;

the production is carried out by using a flat blank with the thickness of less than 110mm, the first hole adopts a structure with a small inclination angle of less than 30 degrees and a low hole height of less than 190mm, and the leg waist included angle is an obtuse angle and is used as the transition between the blank and a subsequent forming hole pattern, so that the use of the thin blank becomes possible; and increasing the inclination angle of the subsequent pass, fixing the positions of the angular points and the circle center after the target pass height is reached, reducing the leg thickness, filling the angular parts, and realizing the stable production of the Z-shaped steel.

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