CN113600622A

CN113600622A - Method for controlling dimension of finished product poker obtained by multi-line slitting of bar

Info

Publication number: CN113600622A
Application number: CN202110836977.7A
Authority: CN
Inventors: 张兴友; 吴俊�; 熊天进; 彭浩波; 何洪庆; 李勇; 马虎; 李天应; 王国祚; 颜伟
Original assignee: Shougang Shuicheng Iron and Steel Group Co Ltd
Current assignee: Shougang Shuicheng Iron and Steel Group Co Ltd
Priority date: 2021-07-23
Filing date: 2021-07-23
Publication date: 2021-11-05
Anticipated expiration: 2041-07-23
Also published as: CN113600622B

Abstract

The invention discloses a dimension control method for a multi-wire bar splitting finished product poker, wherein the initial rolling temperature of a billet is controlled to be 1030-1050 ℃, the head, the middle and the tail of the billet are heated uniformly, the temperature difference is controlled to be within 30 ℃, the deviation of the sizes of the red billet of a rack at the tail end of a roughing mill set is controlled to be within 1.5mm, the sizes of the red billet of the rack at the tail end of a middle mill set are controlled to be within 1.0mm, the sizes of the red billet of the rack at the tail end of the middle mill set are controlled to be within 0.3mm of a standard material type, the stacking-pulling relation is judged through the current of each rack, micro-pulling rolling is adopted, and the size fluctuation of the material type is corrected through the dynamic adjustment of a loop by a finishing mill set; the control method does not adjust the size of the middle section of K3 and K4, avoids causing process accidents, and the size of the head and the tail of the obtained finished product is within the deviation range of national standard requirements, thereby achieving the indexes of yield and fixed length.

Description

Method for controlling dimension of finished product poker obtained by multi-line slitting of bar

Technical Field

The invention relates to the technical field of rolling control, in particular to a method for controlling the dimension of a multi-line bar splitting finished product poker.

Background

When the bar is rolled to be in a small specification, a multi-line splitting rolling process is mostly adopted to improve the production efficiency. The pass system of the multi-line splitting rolling process comprises the following steps: k6-flat roll, K5-edge control, K4-precutting, K3-cutting, K1 and K2 are multi-line rolling, and K1 is a finished product. In the actual rolling process, due to the change of factors such as pass design, rolling temperature, speed, groove abrasion and the like, line differences exist among lines, and the method adopted usually is to adjust the intermediate section area size of K3 and K4 to obtain a finished product, so that the material shapes at the head and the tail are increased sharply, and the impact and the deformation unevenness after a rolled piece bites into a guide and guard piece are increased invisibly, thereby causing process accidents. Meanwhile, the sizes of the head and the tail of the finished product exceed the deviation range of national standard requirements, and the finished product with out-of-tolerance is selected, so that the yield and the fixed-length rate index are greatly reduced.

Disclosure of Invention

The invention aims to: the size control method for the whole poker bar of the multi-line bar splitting finished product is provided, the size of the middle section of K3 and K4 is not adjusted by the control method, so that the process accident is avoided, the size of the head and the tail of the obtained finished product is within the deviation range of the national standard requirement, and the indexes of yield and fixed size rate can be achieved.

A method for controlling the size of a finished product of a multi-wire bar splitting product of a bar includes controlling the initial rolling temperature of a steel billet to be 1030-1050 ℃, uniformly heating the head, the middle and the tail of the steel billet, controlling the temperature difference to be within 30 ℃, controlling the deviation of the sizes of the head, the middle and the tail of a red billet of a rack at the tail end of a roughing mill set to be within 1.5mm, controlling the sizes of the head, the middle and the tail of the red billet of the rack at the tail end of a middle mill set to be within 1.0mm, controlling each material frame of a finish rolling to be within 0.3mm of a standard material frame, judging the stacking-pulling relation through the current of each rack, adopting micro-pulling rolling, and correcting the size fluctuation of the material frame through the dynamic adjustment of a loop by a finishing mill set.

Further, the adjustment of the rotating speed is gradually adjusted from the rough rolling unit to the finished product rack.

The invention has the beneficial effects that:

according to the control method for the dimension of the whole poker of the multi-line bar splitting finished product, the dimension of the middle section of K3 and K4 is not adjusted, so that process accidents are avoided, the head and tail dimensions of the obtained finished product are within the deviation range of national standard requirements, and the indexes of yield and fixed length can be achieved.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments.

Example 1

Taking a phi 12mm straight twisted steel rolled by a five-slitting process as an example:

the initial rolling temperature of the steel billet is controlled to be 1030 ℃, the head, the middle and the tail of the steel billet must be uniformly heated, the temperature difference is controlled to be within 30 ℃, and the material type of a rack at the tail end of a rough rolling unit is controlled as follows: 74.5mm is multiplied by 75mm, and the material type of a rack at the tail end of a middle mill set is controlled as follows: 76mm multiplied by 25.4mm, the high tolerance of the size of a red blank of a finishing mill group is 0-0.3mm, the width is +/-0.5 mm, the current between frames of a roughing mill group is 150, the current between frames of a middle mill group is 100, the current between frames of a finishing mill group is 80, and the stacking and pulling relationship among the units is obtained by referring to a table 1;

table 1:

the tail size of a rolled piece is controlled downwards by adjusting and reducing the loop dropping time of the loop, so that the loop drops in advance, and the phenomenon that the tail size of a finished product is out of tolerance is ensured. By testing the finished products of 3 examples, finished line differences are obtained as shown in table 2.

Table 2:

fixed number of points	Trade mark/specification	Weight management	Excess weight	Weight deviation (%)
					370	HRB400E/12*9	2957	2843	-3.86
370	HRB400E/12*9	2957	2853	-3.52
					370	HRB400E/12*9	2957	2859	-3.31

Example 2

the initial rolling temperature of the steel billet is controlled at 1040 ℃, the head, the middle and the tail of the steel billet must be heated uniformly, the temperature difference is controlled within 30 ℃, and the material type of a rack at the tail end of a roughing mill group is controlled as follows: 75mm is multiplied by 75.5mm, and the material type of a rack at the tail end of a middle mill set is controlled as follows: 76.5mm multiplied by 26mm, the high tolerance of the size of a red blank of a finishing mill group is 0-0.3mm, the width is +/-0.5 mm, the current between frames of a roughing mill group is 120, the current between frames of a middle mill group is 90, the current between frames of a finishing mill group is 70, and the stacking and pulling relationship among the units is obtained by referring to a table 1;

the tail size of a rolled piece is controlled downwards by adjusting and reducing the loop dropping time of the loop, so that the loop drops in advance, and the phenomenon that the tail size of a finished product is out of tolerance is ensured.

Example 3

the initial rolling temperature of the steel billet is controlled to be 1045 ℃, the head, the middle and the tail of the steel billet must be uniformly heated, the temperature difference is controlled to be within 30 ℃, and the material type of a rack at the tail end of a roughing mill group is controlled as follows: 75.5mm is multiplied by 76mm, and the material type of a rack at the tail end of a middle mill set is controlled as follows: 77mm multiplied by 26.5mm, the high tolerance of the size of a red blank of a finishing mill group is 0-0.3mm, the width is +/-0.5 mm, the current between frames of a roughing mill group is 180, the current between frames of a middle mill group is 110, the current between frames of the finishing mill group is 80, and the stacking and pulling relationship among the units is obtained by referring to a table 1;

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.

Claims

1. A method for controlling the dimension of a finished product poker cut in multiple lines by a bar is characterized by comprising the following steps: the initial rolling temperature of a steel billet is controlled to be 1030-1050 ℃, the head, the middle and the tail of the steel billet are heated uniformly, the temperature difference is controlled to be within 30 ℃, the size deviation of the red billet of the rack at the tail end of a rough rolling unit is controlled to be within 1.5mm, the size deviation of the red billet of the rack at the tail end of the middle rolling unit is controlled to be within 1.0mm, the size of the red billet of the rack at the tail end of the middle rolling unit is controlled to be within 0.3mm of a standard material type, the stacking and pulling relation is judged through the current of each rack, micro-pulling rolling is adopted, and the size fluctuation of the material type is corrected through the dynamic adjustment of a loop by a finishing rolling unit.

2. The method for controlling the dimension of the finished product poker cut in multiple lines by the bar according to claim 1, wherein the method comprises the following steps: the adjustment of the rotating speed is gradually adjusted from the rough rolling unit to the finished product frame.