CN113600622B

CN113600622B - Method for controlling size of finished product full bar through multi-line bar segmentation

Info

Publication number: CN113600622B
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: 2023-08-11
Anticipated expiration: 2041-07-23
Also published as: CN113600622A

Abstract

The invention discloses a bar multi-line cutting finished product full bar size control method, wherein the billet initial rolling temperature is controlled at 1030 ℃ to 1050 ℃, the billet head, middle and tail are heated uniformly, the temperature difference is controlled within 30 ℃, the deviation of the red billet size head, middle and tail sizes of a frame at the tail end of a roughing mill set is controlled within 1.5mm, the red billet size head, middle and tail sizes of the frame at the tail end of the middle mill set are controlled within 1.0mm, each frame material type is controlled within the standard material type 0.3mm, the pile-pulling relation is judged through the current of each frame, micro-pulling rolling is adopted, and the finishing mill set corrects the material type size fluctuation through dynamic adjustment of a loop; the control method does not adjust the size of the middle section of K3 and K4, avoids the process accident, and the obtained head and tail sizes of the finished products are within the deviation range required by national standards, thereby reaching the indexes of yield and sizing rate.

Description

Method for controlling size of finished product full bar through multi-line bar segmentation

Technical Field

The invention relates to the technical field of rolling control, in particular to a method for controlling the size of a finished product full bar through multi-line cutting of a bar.

Background

When the bar is rolled to a small specification, a multi-line splitting rolling process is mostly adopted to improve the production efficiency. The multi-line splitting rolling process hole pattern system comprises the following steps: k6-flat roller, K5-edge control, K4-pre-cutting, K3-cutting, K1 and K2 are multi-line rolling, and K1 is finished product. In the actual rolling process, line differences exist in each line due to the changes of hole pattern design, rolling temperature, speed, rolling groove abrasion and other factors, the size of the middle cross section area of K3 and K4 is regulated to be the finished product, so that the material size of the head and the tail is increased sharply, the impact and the deformation unevenness after the rolled piece bites into the guide piece are increased intangibly, and the technological accident is caused. Meanwhile, the sizes of the head and the tail of the finished products exceed the deviation range required by national standards, and the out-of-tolerance finished products are selected, so that the yield and the fixed-size rate index are greatly reduced.

Disclosure of Invention

The invention aims at: the method is used for controlling the sizes of the finished product full bars by multi-line cutting of the bars, the intermediate section sizes of K3 and K4 are not adjusted by the control method, the process accidents are avoided, and the obtained sizes of the heads and the tails of the finished products are within the deviation range required by national standards, so that the indexes of the yield and the fixed-length rate can be achieved.

The method for controlling the size of finished product full bars by multi-line cutting of bars comprises the steps of controlling the initial rolling temperature of billets at 1030-1050 ℃, heating the billets at the head, middle and tail evenly, controlling the temperature difference within 30 ℃, controlling the deviation of the sizes of red billets at the tail end of a roughing mill set within 1.5mm, controlling the sizes of the red billets at the tail end of the middle mill set within 1.0mm, controlling the sizes of the red billets at the tail end of the middle mill set within the range of 0.3mm, judging the pile-pull relation through the currents of the racks, adopting micro-pulling rolling, and correcting the size fluctuation of the finished products by dynamic adjustment of a loop.

Further, the rotation speed is adjusted gradually from the roughing mill to the direction of the finished product frame.

The invention has the beneficial effects that:

the method for controlling the size of the finished product full bar by multi-line cutting of the bar is used for avoiding the process accident caused by not adjusting the size of the middle section of K3 and K4, and the obtained size of the head and tail of the finished product is in the deviation range required by national standard, so that the indexes of the yield and the fixed-length rate can be achieved.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely, and it is apparent that the described embodiments are only some embodiments of the present invention, but not all embodiments.

Example 1

Taking a five-splitting process to roll a phi 12mm straight twisted steel as an example:

the initial rolling temperature of the billet is controlled at 1030 ℃, the heating of the head, the middle and the tail of the billet is required to be uniform, the temperature difference is controlled within 30 ℃, and the material type of the frame at the tail end of the roughing mill set is controlled as follows: 74.5mm x 75mm, the material control of the end frame of the middle rolling mill group is as follows: 76mm multiplied by 25.4mm, the high tolerance of the size of the red blank of the finishing mill group is 0-0.3mm, the width is +/-0.5 mm, the inter-frame current of the roughing mill group is 150, the inter-frame current of the middle mill group is 100, the inter-frame current of the finishing mill group is 80, and the pile-pull relation among the groups is obtained by referring to the table 1;

table 1:

the tail size of the rolled piece is downwards controlled by adjusting and reducing the looper falling time, so that the looper is fallen in advance, and the phenomenon of out-of-tolerance of the tail size of the finished product is ensured. The finished product line differences obtained by examining the finished products of 3 examples are shown in table 2.

Table 2:

fixed number of counts	Number/specification of brand	Weight management	Weight of solid	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 billet is controlled at 1040 ℃, the heating of the head, the middle and the tail of the billet is required to be uniform, the temperature difference is controlled within 30 ℃, and the material of the frame at the tail end of the roughing mill set is controlled as follows: 75mm×75.5mm, the material control of the end frame of the middle rolling mill group is as follows: 76.5mm multiplied by 26mm, the size of the red blank of the finishing mill group is 0-0.3mm in high tolerance, the width is +/-0.5 mm, the inter-frame current of the roughing mill group is 120, the inter-frame current of the middle mill group is 90, the inter-frame current of the finishing mill group is 70, and the pile-up relation among the groups is obtained by referring to table 1;

the tail size of the rolled piece is downwards controlled by adjusting and reducing the looper falling time, so that the looper is fallen in advance, and the phenomenon of out-of-tolerance of the tail size of the finished product is ensured.

Example 3

the initial rolling temperature of the billet is controlled to 1045 ℃, the heating of the head, the middle and the tail of the billet is required to be uniform, the temperature difference is controlled to be within 30 ℃, and the material of the frame at the tail end of the roughing mill set is controlled as follows: 75.5mm multiplied by 76mm, the material control of the tail end frame of the middle rolling mill group is as follows: 77mm multiplied by 26.5mm, the high tolerance of the size of the red blank of the finishing mill group is 0-0.3mm, the width is +/-0.5 mm, the inter-frame current of the roughing mill group is 180, the inter-frame current of the middle mill group is 110, the inter-frame current of the finishing mill group is 80, and the pile-up relation among the groups is obtained by referring to the table 1;

The foregoing is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art, who is within the scope of the present invention, should make equivalent substitutions or modifications according to the technical scheme of the present invention and the inventive concept thereof, and should be covered by the scope of the present invention.

Claims

1. A bar multi-line cutting finished product whole bar size control method is characterized in that: the initial rolling temperature of the billet is controlled at 1030-1050 ℃, the head, middle and tail of the billet are heated uniformly, the temperature difference is controlled within 30 ℃, the deviation of the size head, middle and tail sizes of the red billet of the tail end frame of the roughing mill set is controlled within 1.5mm, the size head, middle and tail sizes of the red billet of the tail end frame of the middle mill set are controlled within 1.0mm, the finish rolling frame types are controlled within the standard material type 0.3mm, the stack-draw relationship is judged through the current of each frame, micro-draw rolling is adopted, the finishing mill set corrects the size fluctuation of the material type through dynamic adjustment of a loop, and the control method does not adjust the middle section sizes of K3 and K4.

2. The method for controlling the size of a finished bar through multi-line cutting of bars according to claim 1, wherein the method comprises the following steps: the rotation speed is adjusted gradually from the roughing mill set to the direction of the finished product frame.