CN103252354B - Method for controlling side turning of hot rolling stainless steel band - Google Patents

Abstract

A method for controlling side turning of a hot rolling stainless steel band belongs to the metallurgy field. The method is characterized in that regarding a rough rolling vertical roll, the side pressure of a first pass is smaller than and equal to 200KN, the side pressure of a third pass is from 300KN to 800KN, and the side pressure of a fifth pass is from 100KN to 300KN. Regarding a rough rolling flat roll, the reduction rate of a first pass is 54.1%, the reduction rate of a second pass is 44.5%, the reduction rate of a third pass is 33.8%, the reduction rate of a fourth pass is 23%, and the reduction rate of a fifth pass is 14.1%. By means of reasonable control of flow deformation of metal in the process of stainless steel hot rolling, the method for controlling side turning of the hot rolling stainless steel band controls rough rolling and broadsiding in an appropriate range, effectively controls the side turning width of the stainless steel band, reduces trimming amount of cold rolling finished products, and improves yield of the cold rolling finished products.

Description

The control method of a kind of hot-rolled stainless Edge of Steel Strip portion rollover

Technical field

The invention belongs to field of metallurgy, be specifically related to the control method of a kind of hot-rolled stainless Edge of Steel Strip portion rollover.

Background technology

Stainless steel has the features such as good corrosion resistance, heat-resisting quantity, lower temperature resistance, mar proof and exquisite appearance, and purposes widely, occupies critical role in space flight, petrochemical industry, ocean development and family are civilian etc.

The current stainless steel technological process of production is mainly: storehouse is handed in steel-making → continuous casting → hot rolling → raw material annealing and pickling → cold rolling → finished products pickling → finished product trimming, packing.

Due to stainless steel casting blank side not reconditioning, there is oscillation mark in surface, wrinkle etc., coarse through heating furnace high-temperature heated oxide rear surface, through the multi-pass rolling of edger roll and plain-barreled roll, the thick hot rolled coil of 3 ~ 5mm is rolled into from thickness 200mm strand, roll thin trailing flank metal and turn to belt steel surface, formed along the elongated rough zone of band steel both sides edge, cold rolling rear elimination is not, for ensureing cold rolling finished surface quality, two edge rough zones will be cut away rear delivery by general finished product, so steel edge portion rollover width directly have influence on cold rolling finished product trimming amount number, affect cold drawing lumber recovery.Before not taking this control method, stainless steel edge one-sided rollover width general control, at 13 ~ 16mm, all can only cut away, cause larger metal loss after cold rolling finished product, so it is anxious to be resolved how to reduce this problem of rollover width.

Summary of the invention

In order to reduce cold rolling finished product trimming amount, improve cold rolling finished product lumber recovery, roughing, by the flow deformation of metal in conservative control stainless steel hot-rolling process, is spreaded and is controlled in OK range by the present invention, effectively controls stainless steel band edge rollover width.

Consider in stainless steel hot-rolling process produce rollover defect mainly due in the operation of rolling continuous casting billet side-overturning formed to belt steel surface, so turn on one's side width and vertical roller side pressure and flat rolling time reduction ratio have comparatively Important Relations.By each passage lateral pressure of reasonable set roughing vertical roll, each percentage pass reduction of plain-barreled roll, controls strand edge metal to surperficial liquidity preference.

By comparative analysis process rolling data, rollover width in Binding protein steel surface is followed the tracks of, find that rollover width and vertical roller side pressure have very strong corresponding relation, the side pressure of ordinary circumstance edger roll is larger, rollover width is wider, after edger roll side pressure reaches a desired value, there is minimum of a value in rollover width, different rolling pass influence degree there are differences simultaneously.For conservative control vertical roller side pressure, need be optimized continuous casting billet and hot rolling width coupling, realize the little side pressure control strategy of edger roll.Namely adopt broadening, little side pressure production technology, require that hot rolling finished width is by being greater than blank width and controlling within the specific limits; The each passage side pressure of reasonable distribution edger roll, determines first and third, five each passage lateral pressure control ranges in conjunction with actual measurement rollover width value.

Analyze simultaneously and show that roughing plain-barreled roll reduction ratio also exists certain influence to band steel rollover width, percentage pass reduction distributes improper, and percentage pass reduction variation also can cause rollover to widen, so rationally need revise each percentage pass reduction, transitions smooth too greatly.

A control method for hot-rolled stainless Edge of Steel Strip portion rollover, it is characterized in that each passage lateral pressure of roughing vertical roll is respectively a time≤200KN, three passages are 300 ~ 800KN, and five passages are 100 ~ 300KN; The reduction ratio of each passage of roughing plain-barreled roll is 1 passage be respectively 54.1%, 2 passages be 44.5%, 3 passages be 33.8%, 4 passages be 23%, 5 passages is 14.1%.

The present invention makes to obtain effective control for cold rolling stainless steel hot-rolling flanging part rollover width, one-sided rollover width is down to 11.5mm from average 14mm, make that cold rolling rip cutting trimming amount is one-sided decreases 2.5mm, by band steel mean breadth 1255mm, then can improve cold rolling lumber recovery: (2 × 2.5mm) ÷ 1255mm=0.398%.

Stainless steel 600,000 tons produced per year by Taiyuan Iron and Steel Co. 1549 line, and steel scrap and finished product price difference, by 3600 yuan/ton, cold rollingly cut damage owing to reducing, and raising lumber recovery creates effect the whole year altogether: 600000 ton * 0.398% * 3600 yuan/ton=859.68 (ten thousand yuan).

Detailed description of the invention

By collecting all kinds of rolling data in stainless steel hot-rolling process, Binding protein steel surface rollover width measured value, through Comparative Study, on guarantee width and rolling stability basis, develops Taiyuan Iron and Steel Co. hot continuous rolling 1549 line steel edge portion rollover control method.Main technical schemes is as follows:

1. optimize continuous casting billet to mate with hot rolled coil finished width, realize little broadening rolling.

For ensureing hot rolled coil finished width, require to realize roughing vertical roll lateral pressure can not be too large simultaneously, needs continuous casting billet and hot rolled coil Proper Match, by little broadening control strategy, through test of many times, determine the narrow 5mm of continuous casting material width desired value specific heat volume finished width and control.

2. determine roughing vertical roll each passage lateral pressure controlling value

Carry out multiple-factor multilevel test by experimental design DOE, found and can realize steel edge portion and to turn on one's side minimum optimum lateral pressure controling parameters:

Roughing passage	A time	Three passages	Five passages
				Vertical roller side pressure control range	≤200KN	300～800KN	100～300KN

3. optimize roughing vertical roll Pressure control model, realize edger roll each passage lateral pressure and be worth automatic control on request, operative employee monitors, and can manually revise spacious and comfortable amount according to lateral pressure situation.

4. each percentage pass reduction of roughing plain-barreled roll is rationally determined:

Claims (1)

1. a control method for hot-rolled stainless Edge of Steel Strip portion rollover, each passage lateral pressure of roughing vertical roll is respectively a time≤200KN, and it is characterized in that three passages are 300 ~ 800KN, five passages are 100 ~ 300KN; The reduction ratio of each passage of roughing plain-barreled roll is 1 passage be respectively 54.1%, 2 passages be 44.5%, 3 passages be 33.8%, 4 passages be 23%, 5 passages is 14.1%.