CN104998927A - Thick standard hot rolling nose plate thermal straightening process - Google Patents

Abstract

The invention discloses a thick standard hot rolling nose plate thermal straightening process, comprising the steps of: firstly, avoiding a steel plate nose part, and then straightening by small rolling reduction in a backward direction, thus avoiding the collision between the head of a nose plate and a straightening roll and reducing the buckling rate of the nose plate; then straightening by large rolling reduction in a forward direction to fully straighten the nose plate. The process adopts a method of firstly avoiding the steel plate and then straightening by small rolling reduction in the backward direction, the problem of collision of the head and the straightening roll in a conventional straightening process of the nose plate is solved, and the buckling rate of the nose plate is greatly reduced; through a method of straightening by large rolling reduction in the forward direction, the nose plate is fully straightened, the cutoff amount of the head of the steel plate is greatly reduced, and yield is improved.

Description

A kind of think gauge hot rolling nose plate thermal straightening technique

Technical field

The invention belongs to steel rolling field, relate to a kind of think gauge hot rolling nose plate thermal straightening technique.

Background technology

By the impact of rolling centerline skew, top and bottom rolls diameter and speed discrepancy in Plate Rolling Process, there is nose or lower button phenomenon in steel plate head, causes steel plate to insert roller-way.Although operating personnel can artificially adjust, be difficult to adjust to perfect condition, subsequent thermal straightening process can only be relied on and process.Thermal straightening machine is as the important means of rolling the redemption of rear plate shape, and have more advantage than cold leveling, thermal straightening process steel plate still keeps certain temperature, is with warm steel plate yield strength lower, under same flexure curvature condition, larger plastic deformation can occurs.In addition, be with warm steel plate can reply in straightening process, effectively reduce work hardening and and the residual stress of aligning generation.

For preventing occurring discount in Plate Rolling Process, cause roller-way to damage, course of hot rolling light plate head is multi-control makes micro-sticking up, but actual depth of camber is difficult to control, often there is the too high phenomenon of nose, cause steel plate cannot normally to nip the thermal straightening machine (as shown in Figure 1) of pre-set roll gap.For preventing steel plate head from damaging straightener, straightener roll gap can only be opened by operative employee fast, and steel plate sky crosses straightener, treats that monoblock steel plate sky has been crossed and oppositely aligns.Because rolled piece is oversize, steel plate in the process temperature drop is large, especially head temperature drop is even more serious, causes its leveling effect to decline, and can only ensure that plate shape is qualified by increasing head resection, rolling lumber recovery is caused to decline thus, in addition, the straightening temperature of monoblock steel plate reduces, and steel plate internal stress also can be caused to increase, make steel plate there is the bent hidden danger of secondary wooden dipper in later stage cutting use procedure, affect user and use.

Summary of the invention

The object of this invention is to provide a kind of think gauge hot rolling nose plate thermal straightening technique, this technique crosses steel plate by taking first sky, the method that rear light reduction is oppositely aligned, both avoids the problem of head impact smoothing roll in the conventional straightening process of nose plate, considerably reduces again the amount of warpage of nose plate; By the method for heavy reduction forward secondary aligning, nose plate is aligned completely, steel plate head resection is significantly reduced, improves lumber recovery.

The present invention is achieved through the following technical solutions:

A kind of think gauge hot rolling nose plate thermal straightening technique, is characterized in that: this technique is first empty crosses steel plate nose part, and rear light reduction is oppositely aligned, and avoids nose plate head impact smoothing roll, reduces the amount of warpage of nose plate; Then by heavy reduction forward secondary aligning, nose plate is aligned completely.

Concrete steps are as follows:

1) straightener operating personnel find that hot rolled plate Head ski-up is serious, steel plate cannot normally be nipped straightener, press top roll box immediately and suddenly lift button, straightener roller box fast lifting is to precalculated position, heat inspection, roller table speed and Time Calculation before one-level utilizes straightener machine simultaneously also follow the tracks of steel plate head position, after head nose part is all through straightener, steel plate stops automatically;

2) one-level automatically sets reverse smoothing roll according to the light reduction straightening process of operating desk and is sewn to desired value, and straightener starts oppositely aligns pattern, and treat that steel plate head passes straightener, steel plate stops automatically;

3) one-level automatically sets forward smoothing roll according to the heavy reduction straightening process of operating desk and is sewn to desired value, and straightener starts forward aligning pattern, completes the aligning of monoblock steel plate.

The invention has the beneficial effects as follows: by taking first sky to cross steel plate, the method that rear light reduction is oppositely aligned, both avoiding the problem of head impact smoothing roll in the conventional straightening process of nose plate, considerably reducing again the amount of warpage of nose plate; By the method for heavy reduction forward secondary aligning, nose plate is aligned completely, steel plate head resection is significantly reduced, improves lumber recovery.

The present invention successfully solves the problem that think gauge nose plate cannot realize Rapid Thermal aligning, has significantly fallen think gauge nose wrench portion resection, has improve lumber recovery, and after making aligning, the distribution of steel plate internal stress is more even simultaneously.

Accompanying drawing explanation

Fig. 1 is in prior art, and nose is too high, causes steel plate cannot normally to nip the thermal straightening machine schematic diagram of pre-set roll gap.

Fig. 2 (a) is in the present invention, steel plate head warpage cause steel plate cannot normally nip straightener time straightener roller box fast lifting to the schematic diagram in precalculated position.

Fig. 2 (b) is in the present invention, after steel plate head warped portion passes straightener, and the self-braking schematic diagram of steel plate.

Fig. 2 (c) is in the present invention, and straightener starts oppositely aligns pattern, treats that steel plate head passes straightener, the self-braking schematic diagram of steel plate.

Fig. 2 (d) is in the present invention, and straightener starts forward aligning pattern, and setting smoothing roll is sewn to the schematic diagram of desired value automatically.

In figure, 1-straightener; The inspection of 2-heat; 3-nose plate.

Detailed description of the invention

A kind of 30mm yield strength is 350MPa nose plate thermal straightening technique.The straightener roller footpath that this technique uses and roll spacing are respectively 215mm and 230mm, and roller box maximum inclination is 8mm.Rolled piece cannot normally to be nipped straightener because of Head ski-up, and rolled piece is always about 60m.The straightener inlet roll gap of this technological requirement light reduction straightening process is 19mm, and outlet roll gap is 20mm; The straightener inlet roll gap that heavy reduction straightening process is rectified is 18mm, and outlet roll gap is 20mm.Roll gap is lifted in employing soon makes nose plate pass through straightener, before utilizing machine by one-level, steel plate head position is followed the tracks of in heat inspection, pass after straightener 2m until steel plate head, one-level also starts oppositely aligning according to small deformation straightening process automatic reverse setting roll gap, after having aligned, one-level sets roll gap according to the automatic forward of large deformation straightening process and starts forward aligning.One-level refers to the one-level automated system in the technique of steel rolling field.

Detailed process is as follows, sees Fig. 2:

(1) straightener operating personnel find that hot rolled plate Head ski-up is serious, steel plate cannot normally be nipped straightener, press top roll box immediately and suddenly lift button, straightener roller box fast lifting is to predetermined 200mm position, as Fig. 2 (a), heat inspection, roller table speed and Time Calculation before one-level utilizes straightener machine simultaneously also follow the tracks of steel plate head position, when steel plate head is through after the presetting length 2m of straightener, steel plate stops automatically, as Fig. 2 (b).

(2) one-level sets the roll gap of oppositely aligning automatically according to the light reduction straightening process of operating desk: export as 19mm, entrance are 20mm, as Fig. 2 (c).Straightener starts oppositely aligns pattern, and treat that steel plate head passes straightener, steel plate stops automatically;

(3) one-level sets the roll gap of forward aligning automatically according to the heavy reduction straightening process of operating desk: export as 20mm, entrance are 18mm, as Fig. 2 (d).Straightener starts forward aligning pattern, completes the aligning of monoblock steel plate.

Claims (2)

1. a think gauge hot rolling nose plate thermal straightening technique, is characterized in that: this technique is first empty crosses steel plate nose part, and rear light reduction is oppositely aligned, and avoids nose plate head impact smoothing roll, reduces the amount of warpage of nose plate; Then by heavy reduction forward secondary aligning, nose plate is aligned completely.

2. thick size hot-rolled nose plate thermal straightening technique according to claim 1, is characterized in that these technique concrete steps are as follows:

1) straightener operating personnel find that hot rolled plate Head ski-up is serious, steel plate cannot normally be nipped straightener, press top roll box immediately and suddenly lift button, straightener roller box fast lifting is to precalculated position, heat inspection, roller table speed and Time Calculation before one-level utilizes straightener machine simultaneously also follow the tracks of steel plate head position, after head nose part is all through straightener, steel plate stops automatically;

2) one-level automatically sets reverse smoothing roll according to the light reduction straightening process of operating desk and is sewn to desired value, and straightener starts oppositely aligns pattern, and treat that steel plate head passes straightener, steel plate stops automatically;

3) one-level automatically sets forward smoothing roll according to the heavy reduction straightening process of operating desk and is sewn to desired value, and straightener starts forward aligning pattern, completes the aligning of monoblock steel plate.