SU1606220A1 - Method of straightening rolled stock - Google Patents

Abstract

The invention relates to the processing of metals by pressure, in particular to methods for straightening profile rolled products on machines with swing collars. The purpose of the invention is to increase productivity by increasing the speed of moving the rolled along the axis without reducing the quality of the dressing. The car is moved through two successively located BOs by means of feed rollers mounted on both sides of the BOs, which move along closed trajectories in planes perpendicular to the axis of the car’s supply. In the first one, in the course of the QO displacement, plastic deformations cover at least 2/3 of the rolled section, and in the second QO, it is bent until the greatest elastic bending moment occurs. The paths of the QO movement are determined from the condition of the occurrence of the specified rolling deformations. A mathematical relationship is given to determine the speed at which the rolled stock moves along the axis. 3 il.

Description

The invention relates to the processing of metals by pressure, and in particular to methods for straightening profile rolled products on machines with tilting holders.

The purpose of the invention is to increase productivity by increasing the speed of moving rolled steel along the axis without degrading the quality of rolling.

Figo shows the straightening diagram and the distribution diagram of the bending moments along the longitudinal axis of the rolled metal; on fig2 - section aa on figo1; figoZ - section BB on FIGO 1,

The method of straightening includes the translational movement of rolled 1 by feed rollers 2 through two swinging collars 3 and 4 and its deformation by repeated alternating bending in all longitudinal planes by synchronously moving sections I and II of rolled metal in collars 3 and 4 with respect to coaxially arranged sections III in feeding rollers 2 (Figs 2 and 3) along closed trajectories 5 and 6 clips in planes xj perpendicular to the direction of translational movement of the car. In this case, the distances R and R 2 from the orbits of the trajectories 5 and 6 to their centers in each plane are determined from the condition of occurrence in section I of the rolled product in the first along its movement 3 of elastoplastic bending.

of this moment, when plastic deformations cover not less than 2/3 of this section, and in section II of rolled metal in the second cage 4 - the greatest elastic bending moment M, the highest speed v of the rolling movement of rolling is determined by the formula

, v nt,

where n is the frequency of swinging the clips 3 and 4 along a closed trajectory m 5 and 6; t is the distance between clips

3 and 4o

Dp of creating in sections I and II of rolling, respectively, the bending moments gam and M y in each longitudinal plane of rolling, these sections are moved in cages 3 and 4 along corresponding closed trajectories m 5 and 6. The nature and dimensions of the trajectories depend on the shape and size of the rolled products, and also from the distance between the rolled sections passing through the rollers and the holder. The gauges of the rollers 2 are coaxial. From the theory of editing:

gam mW;

GT- Wo

M

The relative bending moment m is taken for a specific rolled product so that plastic deformation covers at least 2/3 of the section. The moment of resistance W is also determined for a specific rolled metal.

I

Then determine which bending moments M and M get rolled in near to the yoke feed rollers M less than H and therefore does not cause plastic deformation. After this sign of the distribution of bending moments, the distances E. and Rj are determined, the differential equations of the curved axis npokaTa are determined. Similar calculations for each longitudinal plane of hire determine the nature and dimensions of the trajectories 5 and 6, according to which the type of mechanisms for swinging the clips is selected. Fixed rolling 1, moving progressively, is subjected to multiple planar multiple alternating bending. The amount of bending gradually increases and reaches the maximum value.

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in the first holder Zo, the plastic deformation encompasses at least 2/3 of the cross section and by this moment the whole rolled curvature of the rolled product in each outgoing and longitudinal plane is reduced to

some TQ constant curvature -.

In the area between the cages, the magnitude of the bending moment gradually decreases to the largest elastic bending moment in less than three bends (condition of quality straightening) in all longitudinal planes. Then the rolling is not subjected to plastic deformation. Thus, it is precisely in the area between

ferrules 3 and 4 curvature reduces

R

to admissible curvature

ir

When

step movement of rolled stock

2 V - nt speed is provided

best performance when you perform quality editing. Any reduction in the editing speed leads to an increase in the accuracy of the editing, but at the same time the productivity decreases. If the speed is increased above the specified value, the condition of qualitative editing is violated, therefore the correction accuracy decreases

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PRI m e RO Fixable material - hexagonal steel with a diameter of 32 mm in diameter d, j, jj with a yield strength of material O y 80 kg / mm s Equipment - the correct machine with two swing collars and feed rollers

The spacing between the feed rollers is 440 mm, between the clips and the feed rollers 500 mm, between the collars (t) 550 mm, the frequency of oscillation of the collars (n) 50 - 240 rpm.

Rolling speed

D

pp ttp

V

60

 0.25 - 1.25 m / s.

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where d

etc

P

240 mm - diameter of the feed rollers;

20 - 1000 r / m - the speed of their rotation. The mechanism for swinging the clips is made in the form of a connecting rod carrying a roller cap.

R

W

 15 DE 144 WHH

15 -5 O -3 /

516

the libre and rocker arms hinged to it and the drive crank of adjustable length. The length of the crank can vary from 0 to 28 mm, it defines the dimensions of the trajectories, the length of the rocker arm is 60 mm, the length of the connecting rod is 1300 mm, and the roller gauge is placed on the rod at a distance of 600 mm from the hinge connecting it to the rocker.

For hexagonal rolled metal, due to the condition of qualitative straightening (that is, when plastic deformations cover at least 2/3 of the cross section), it suffices to take the relative bending moment m

When bending in the vertical plane YZ, the moment of resistance of rolled W of hexagonal section is determined by the formula

 M ,, 0 W 8000кЗ, 4 27200 kgcm

272 kgm; tm t 1,5x27200 40800 kgcm

  408 kgm; M. 0.6, 4 M, 0.6. 408 + 0.41

X272 353.6 kgm; M 0.4 shMuu + 0.32 M, 0.4.408 + + 0.32-272 250.2 kgm,

By knowing the distribution of bending moments along the longitudinal axis of the rolled product, it is easy to determine the necessary Rj and Rn

  m; dz Ё1:

pM is the current value of the bending moment;

I. - the moment of inertia of the section of rolling when it bends in the considered longitudinal plane:

ai iij "; "; - iil

M: dz

Substitute the values of dp Z 440 + +500 940 mm and Zg 440 + 500 + 550 1490 mm, we define: R, 18 mm, and

Mmo

Speed (highest) of translational movement

R 12

about 2 V I nt ,,: X X 0,, 25 m / Cc

Here, 205 rpm, and the correction accuracy is 1 mm / m.

Thus, the invention makes it possible to increase productivity by 3 times while ensuring the same accuracy of edits.

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Claims (1)

Invention Formula The method of straightening a car by moving it successively through two clips, swinging along closed trajectories in planes perpendicular to the axis of movement of the car, with multiple alternating} first elastic-plastic bend, in which plastic strains cover at least 2 during the course of the holder 3 sections of the rolling stock, characterized in that, in order to increase productivity, in the second casing, the rolling is bent to the occurrence of the greatest elastic bending moment, with the greatest speed moving and rolled v-axis is V nt where n is the frequency of oscillations of the clips; t is the distance between clips Mi fpua2 mMw (rig. 3 Compiled by IoHopt on Editor Mopetrova Tehred L. Serdgakov Corrector V Girn Order 3513 Circulation 607 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 Production and Publishing Combine Patent, Uzhgorod, st. Gagarin, 101 Subscription