SU1593720A1 - Method of adjusting roll moulding mill - Google Patents

Abstract

The invention relates to the processing of metals by pressure, in particular, to methods for setting up molding mills for pipe electric welding machines. The purpose of the invention is to improve the quality of molded pipes. The setting method of the roll forming mill is as follows. In the stand of the mill along the length of the hearth molding establish precast horizontal and vertical rolls. A molding center is preliminarily constructed with a monotonous change in the geometry of the cross sections of the pipe billet; it is divided into a number of parallel sections. In each cross section of the horizontal projection of the monotonous center of the molding, determine the angle α of inclination to the axis of the molding perpendicular to the tangent in this section to the horizontal projection of the center of the molding. In the vertical projection of the monotonous molding center, the angles of inclination to the vertical perpendicular to the upper and lower tangents to the projection of the molding center are determined. After determining the angles, the halves of the horizontal and vertical rolls are rotated and their axes are set at the corresponding angle to the forming axis. Mathematical dependences for the specified angles are determined for a straight molding center with a single bend point. The setting of the forming mill according to the described method allows to reproduce the natural conical center of folding. This leads to a significant decrease in the roll effect and, therefore, reduces the peaks of tensile stresses on the edges of the moldable billet at the entrance to the roll gauge, and also increases the length of the contact deformation zone in each local roll gauge. This reduces the opening zone of the billet at the exit. 1 hp ff, 5 ill.

Description

The invention relates to the processing of metals by pressure, in particular, to the adjustment of molding mills of pipe welding equipment.

The purpose of the invention is to improve the quality of the pipes by eliminating the defects in the molding characteristic of the local roller hearth (corrugation).

FIG. Figure 1 shows a horizontal projection of a monotonous center of forming with customized upper combined horizontal rollers, top view (the lower combined horizontal and vertical rollers are not shown); in fig. 2 - the same, with tuned lower precast horizontal rollers, bottom view (upper precast horizontal and vertical rolls

not shown); in fig. 3-projection on the vertical plane passing through the axis of the molding, of the monotonous center of the molding with customized prefabricated vertical rolls; Fig. 4 is a horizontal projection of a monotone molding; in fig. 5 is a projection on a vertical plane passing through the axis of the molding, of a monotonic center of molding,

In FIGS. 1-5, the following signs are accepted: “1,, ct3, CU4 are the angles of inclination of the axes to the forming axis of each half of the upper combined horizontal rolls, respectively, of the first, second, third, and fourth deforming sections;

/ Jl, jSz, / Z3 are the angles of inclination of the axes to the vertical of the upper halves of the combined vertical rolls of the first, second and third deforming sections, respectively;

jSi, 2,; 5з are the angles of inclination of the axes to the vertical of the lower halves of the combined vertical rolls, respectively, of the first, second and third deforming sections;

B - tape width; L - the length of the hearth molding; X - rastroenie from the beginning of the focus of formosis

ki up to the cross section; S is half the width of the cross section of the monotone molding in the section under study; A - tangent to the horizontal projection of the monotonous center of forming in the section under study; С - perpendicular to the tangent; H is the height of the cross section of the monotone molding in the section under study;

The E-top is tangent in the section under study to the Projection of the monotonous core of the molding on the vertical plane passing through the axis of the molding;

G is perpendicular to the tangent. The method for adjusting a roller molding mill is carried out as follows.

In the cage of the forming mill along the length of the center of the molding set precast horizontal and vertical rolls. Each half of the assembled horizontal rolls are rotated at an acute angle to the forming axis so that their axes become perpendicular to the tangents to the horizontal projection of the billet in the forming center in this deforming section. The upper half of the precast vertical rolls turn so that

0

five

0

their axes are perpendicular to the tangent to the projection of the edges of the billet b of the molding center on the vertical plane passing through the forming axis in this deforming section. Then, the lower halves of the prefabricated vertical rolls are rotated so that their axes are perpendicular to the tangent to the projection of the fiber-width of the tubular billet in the forming center on the vertical plane passing through the forming axis in this deforming section. Next, the strip is fed to the forming roller mill.

For a single radial molding center, angle a. the inclination of the axes of the assembled horizontal rolls to the forming axis at the angle of forming the tubular billet from 0 to 180 ° is determined by the ratio

lHV / uZTHh

a - barctg - (cos () L „: / YAH

Yah

d))

and at the angle of forming the pipe billet over 180 ° by the ratio

l / bl a --arctg (-),

2 2 l: x

In this case, the angle / 3 of inclination of the upper half of the precast vertical rolls to the vertical is determined by the ratio

/ 3 "arctg | (sln

 . l: x v l / / / j

For this hearth of forming, the angle of inclination of the lower halves of the precast vertical

rolls to the vertical / 3 0.

According to the laws setting

The roller tool of the forming mill is quick and reliable. For this, the angles of each half of the collection rolls for each cell are calculated by ratios, and then the rolls are turned until they reach the calculated values.

Setting the roll forming mill according to the proposed method allows to reproduce the natural conical

a folding center, in which the forming tool, which is in contact with the tubular billet in the course of forming, copies the conical center of folding of the tubular billet. This leads to a significant

reduction of the roll effect and, therefore, reduces the tensile stresses of the tensile stresses at the edges of the forming billet at the entrance to the roll gauge. In addition, the setting roller molding mill proposed method

allows you to increase the length of the contact deformation zone in each local roll tube, which, in turn, leads to a decrease in the off-contact strain zone, deformation before entering the local roll gauge and a decrease in the opening zone (springing) of the pipe billet after leaving him Reducing the zone of non-contact deformation of the tube blank reduces the tensile stresses at its edges. A decrease in the billet opening zone leads to a decrease in the edge load (relieving tensile stresses on them) and to a decrease in the natural unfolding of the tube billet in this zone.

Thus, the proposed method for adjusting a roll forming mill eliminates the possibility of forming corrugations (waves on the edges) of the tube billet by reducing the stresses on the edges of the tube billet in the area of non-contact deformation and in the zone of contact deformation of each roll gauge along with a decrease in edge unloading a billet opening zone; reduce the length of the forming mill without sacrificing the quality of the molding by completely eliminating the conditions for the corrugation of the pipe billet and energy consumption of the tube electric welding material for molding by reducing the angle of the natural forming of the pipe billet in the open area, since the subsequent rolling gauge requires less work of the bend, etc. ..

The mathematical laws of variation of the angles of inclination of each half of the rolls for a single-radial straight molding center are obtained analytically.

The central fiber width in this center is horizontal straight line, so in any cross section the lower tangent to the projection of the monotonous center of molding on the vertical plane passing through the axis of the molding is horizontal straight line. Therefore, the lower half of the precast vertical rolls set vertically (Fig. 4 and 5).

For a given hearth, the angle p of the molding is i-. varies monotonically along the length L of the center of the molding from O to 2. tg, i.e.

2l: x P -.

Then the radius R of the curvature of the molding is distributed over the center of the molding as follows;

0

five

0

five

P 2 to

Thus, half the width of the cross section. S formable pipe billet along the length of the center of the molding, with the angle of forming the pipe billet from 0 to 180 ° has the form

x

Si R

ci "2- BL

sln, (1)

0 and at the angle of forming the pipe billet over 180 °

  2lb- (2)

The height of the cross section H of the form-5 of my pipe billet along the length of the hearth of the molding is equal to

H R / 1 - (- (1-,

cos

2lgh

° Mif))

(3)

Formulas (1) and (2) determine the analogous expression of the horizontal projection of the center of molding relative to the axis of molding.

Since this core of the molding has a central fiber-width horizontal straight straight line, formula (3) defines the analytical expression of the projection of the edges of the tubular billet on the molding core on the vertical plane passing through the axis of the molding; relative to the central width of the fiber band.

The analytical dependencies that determine the tangents of the angles of inclination of the tangents to the ordinate axis along the length of the forming core are obtained by deriving the X derivative of expressions (1), (3)

 diSi dC () -slnf x / L)) dxdx

 ) vlLEiLCzBAl} - ik. oi

. A Sin I.

2jrx

)

+

-four-

   L

 . d (rx / L) BL

dx

2 x

X

five

Xsin

/ l; x, BL

 - I + cos

r)

 L / 2YAH

/ X n.

iT-jT / 2i J ..cin / E

Sf /.

st (- (t)

- ... - d S2 d (BL / 2 LX) BL

dx

dx

m))

BL 2lgh2

 :

.d (() (1 -cos (rx / L)))

. dx

 dlBiV2 x}. / 1 -cos (+, L P 2l: x

d (1-cos (jrx / L)) BL dx2 x2

(, -cos (2))

BL 2 TTx

sin

 Jrx

lh |

xdiirxA} BL (F) + dxT.TTv L //

/ 7GH TT By sin (, -2 X

x (s, n (2)

Yah

- (1 .- cos (

)))

Since the axes of each half of the assembled horizontal rolls are perpendicular to the tangents to the horizontal projection of the forming core in this deforming section, the angles and the inclination of these axes to the forming axis are determined as follows;

a f + y-f +

25

+ arc, (cos (f) -i

h, "()) 30

.five

a 5+ at 5-agpv

2

(4) (5)

2 2- 2 liters: x.

Since the axes of the upper halves of the prefabricated vertical rolls are perpendicular to the tangents to the projection of the edges of the billet in the forming center on the vertical plane passing through the forming axis in this deforming section, the angles of these axes to the vertical are determined by the ratio

 e, rc4r (i (sm (5i)

(

j x

 Cos

yy

t:

/

(6)

PRI me R 1. Forming mill ADST 5-25-1 for the production of pipes from non-ferrous metals and alloys using argomodug welding method sets a cage, three open horizontal molding cages, a vertical forming cage, two

x

ten

15

20

25

thirty

3.5

40

45

50

55 covered molding stands and a vertical roller bearing unit, For this mill, the length of the center of the molding L 80GMM. For the manufacture of pipes with a diameter of 25 mm and a wall of 1.5 mm of copper Ml, a tape width of 5 mm is used.

The section of the master cell is taken as the beginning of the forming center, and the distance x from the beginning of the forming center to the deforming sections — forming calibers is taken from the technical characteristics of the mill.

For a single-radius straight-line nidus of forming, the angles and inclination of each half of the assembled horizontal rolls to the forming axis for open stands are determined by the formula (4), for closed stands by the formula (5) Angles / 3 of the inclination of the upper halves of the assembled vertical rolls to the vertical are determined Formula (6) for a given mold. The results of the calculation are summarized in Table 1, the data of which are used to adjust the roller tool of the forming mill.

Example 2. A TESA 10-60 molding machine for pipe production by argon-arc welding has a driver stand, four open horizontal molding stands, two closed molding stands and six vertical molding stands located between the horizontal stands. For this mill, the length of the hot spot is mm.

For the manufacture of pipes with a diameter of 40 mm and a wall of 2 mm from steel 12X18H10T, a tape width of 5 mm is used.

A section of the setting stand is taken as the beginning of the forming center, and the distance x from the beginning of the forming center to the deforming sections of the forming gauges is taken from the technical characteristics of the mill.

For a single-radius rectilinear hearth of forming, the angles of inclination of each half of the combined horizontal rolls to the forming axis for open stands are determined by formula (4), for closed stands by formula (5). The angles / 3 of the inclination of the upper halves of the prefabricated vertical rolls to the vertical are determined by the formula (6) for a given molding center. The calculation results are summarized in table. 2, according to which the adjustment of the roller tool of the forming mill.

The application of the proposed method for adjusting a roll forming mill allows improving the quality of pipes by eliminating the possibility of formation of a defect in the molding, reducing the length of the forming mill and improving the energy output characteristics of TESA.

Claims (2)

Formula 1: A method for adjusting a roll forming mill, including placing prefabricated horizontal and vertical rolls along the length of a roll forming center, turning each half of the prefabricated horizontal rolls at an acute angle to the forming axis and winding the strip, characterized in that horizontal and vertical projections of the forming core with a monotonous change in the geometry of the cross sections of pipe billet, break them into a number of parallel sections arranged perpendicular For each axis of the molding, in each cross section of the horizontal projection, the angle a of inclination to the axis of the molding is determined perpendicular to the tangent in this cross section drawn to the horizontal projection of the center of the molding, and in the vertical projection the angle of vertical to perpendicular to the upper and lower tangent to the projection of the monotonous molding center, and the rotation of each half of the horizontal rolls is carried out at an angle equal to the angle and the vertical shafts are also rotated, setting the axis of the upper halves under angle / 3, and the bottom - at an angle /. 2. The way pop, 1, exe and the cup and that. In order to adjust the roller tool for a single-radius rectilinear core of the molding with one bend, the angle and inclination of the axes of the assembled horizontal rolls to the axis of the molding at the angle of forming the tubular billet from 0 to 180 ° is determined by the ratio A. (", (Ex (  t and at the angle of forming the tube billet over 180 ° ratio a | -ags, d (-VTs),  ) the angle / 9 of inclination of the axes of the upper halves of the vertical rolls to the vertical is determined by the ratio , (., n (Ei - gz ( where B is the width of the tape; X is the distance from the beginning of the forming center to the section under study; L - the length of the hearth molding, and the axis of the lower halves of the vertical rolls have a vertical position. ))) Table 1 table 2 FIG. 2 а.З Figm FIG. five