SU1202661A1 - Method of adjusting a mill for moulding channel - Google Patents

Description

The invention relates to the processing of metals by pressure, in particular to the production of cold single curved profiles by roll profiling of a roll bending mill,

The purpose of the invention is to improve the geometry of the profiles and increase productivity by extending the service life of the roll.

The essence of the proposed method lies in the fact that when setting up a mill for channel molding, the width of the calibers of the pre-finishing and finishing stands of the mill increase as the upper rolls wear along the radius of the curvature itself, accepting increases of φ of the width of the finishing and d1 widths of the pre-finishing caliber are equally equal

1) (1.0-1.2UP and Db (0.4-0.6) D where AR is the difference in the values of the current and initial radii of curvings of the rolls of the finishing stand.

It is known that the sweep width of a curved shveogucher BR (i.e., the width of the original billet for its profiling; depending on the values of TOL11Ts-1NY. Profile S, bending radius R width of the shelves B and height of its wall H is determined from the expression (excluding thinning places giba)

 + a & - (R + Sbh ()

 H + Z6-Z, li35 -0.86f,. .

moreover, the width of the rounding sections of the channel is determined by the neutral deformation line that falls in the middle of the thickness of the workpiece.

Consequently, at a constant Bj, H Vi 5 for a given channel, but with an increase in R due to roll wear, an increase in the width B of the shelves also occurs, the geometrical dimensions of the profile are greater than the tolerances, which reduces the quality of products

If, however, as the upper rolls increase in R, to produce an expansion Editor 0, Burer

Compiled by L, Samokhvalova Tehred S, Migunova

Order 8351/9 Circulation 774 Subscription,

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab ,, d, 4/5 Branch PPP Patent, g, Uzhgorod, ul. Project, 4

By increasing the gauge size by increasing the H of the channel, then up to a certain point the width of the shelf can be maintained unchanged. However, in this case, it is necessary to establish the relationship between the required amount of change in the width of the caliber b and the increase in R (the bend radius is easily determined on the finished profile), and this relationship should be acceptable and with some fluctuations in the thickness of the original piece.

In addition, if the mill is configured to form channel profiles only by expanding the gauge of the finishing stand, it will inevitably lead to a narrower profile coming out of the pre-gauge gauge from entering this gauge, which will increase the wear of the upper rolls of the finishing stand and worsen the geometry of the finished channel. Therefore, when setting up the mill, simultaneously with changing the width of the finishing caliber, it is necessary to change the width of the pre-caliber by a certain optimal value, because otherwise, for the reasons stated, the wear of the upper roll of this caliber will increase.

Experimental verification of the proposed method of setting up a mill for forming channels and made on the profile-- bending unit 2-8 100-600 Magnitogorsk Iron and Steel Works.

Experimental rolling showed that the optimal broadening of the finishing gauge for an equal-shelf channel is 4L (1.0-1.2) LC, a small value of D does not guarantee a 100% yield of profiles (according to shelf size) of increased quality, A large value of L can exceed the height tolerances of the channel.

The implementation of the proposed method of setting up a mill for forming channel bars improves the quality of the profiles produced, as well as improves productivity by reducing the number of transshipments.

Proofreader E.Roshko

Claims (1)

METHOD FOR CONFIGURING THE MILL FOR FORMING OF CHANNELS, including adjusting the width of the gauges, characterized in that, in order to improve the geometry of the profiles and extend the service life of the rolls, the gauge width of the finishing and finishing stands of the mill is increased as the upper rolls wear over rounded sections, taking into account an increase in the width fine and final calibers respectively equal Δ b = (1.0-1.2) D K and n '= (O, 4'O, b) d, where r is the difference between the current and initial radii of curvature of the rolls of the finishing stand, mm ¹ , b - increase in the width of a pure caliber, mm; A'b - increase in the width of the pre-finishing caliber, mm.