SU1245362A1 - Method of rolling billets - Google Patents

Description

The invention relates to ferrous and nonferrous metallurgy and can be used in experimental studies of the deformation process during rolling.

The purpose of the invention is to ensure the accuracy of measurement during the experimental studies of the rolling process, the deformation of the pre-coated workpiece.

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Fig. I shows a rolling pattern with forces applied to the workpiece, balanced in the workpiece itself; pas figs. 2 shows a section in FIG. I; I in FIG. 3 is the rolling scheme of odiobre I; 1ino two billets; on fit.4 - way forward In fig.Z; in FIG. 5, a plot of pressure. metal on rolls with external force prilolsinm; on .6 - the same, with the application of internal forces.

The method is implemented by rolling a hollow billet I, in which a hydraulic jHuyip 2 is installed. The workpiece is rolled,. in calibrated rollers 3, equipped with sliding, 1M primt-um 4, connected L with yopopo 5 and with rod 6 of cylinder 2,

8 rolls 7 and 8 can be rolled simultaneously two solid blanks

9 and 10, with grooves at the ends. inserts insert strips 11, which are} steppe with the hydraulic cylinder case and its stem, and the cylinder

2 set between blanks. The method is carried out as follows.

In the hollow billet 1 is installed from the cylinder 2, the stop 5 is inserted with the clamp 4 and secured against movement relative to the cooking. Further, from the hydraulic system they create in the cylinder 2 the pressure 1-1-e and it, through the rod 6 and the stop 5, stretches the workpiece 1 by a predetermined force.

Thereafter, rolling at hollow billet 1 with room 1 is located at room temperature along with clearance by hydraulic cylinder 2 in rolls 3 with round gauges. In this case, the masses of the rolling force are measured, the torque on the spindle x is strain gauges, or other known methods, and the deformation power is measured. All parameters are measured during rolling without tension and with tension under the same conditions, which allows investigating the effect of

0

five

0

five

0

five

0

five

condition on the power parameters,

Subsequently, the rolling of the workpiece is carried out during the reverse, rolls 3 in the opposite direction. This cycle is repeated 5 times during a series of passes, measured;: with this, forces and power.

For 1), the shock 1 lengthens during the elastic deformation, and accordingly the distance between the cylinder 2 and the stop 5 increases with the movement of the rod b,

Tension in the workpiece can be created through the sliding clamp 4 by pressing its elements against the B1HUTHHii surface of the workpiece, while the FORCES put the load alternately in pa3jni4nb x sections along the e;

After the end of the rolling, the cylinder 2 113 of the workpiece is removed.

When rolling p, woo: in-line ras-. 9n 10 preforms are stretched or squeezed through the strips 11.

According to the proposed method, a (5) pre-enrichment can be ensured: i-p-elongation or compression of the workpiece.

On fsh, 5 given diagrams of normal pressure with attached P1em front.; tension with voltage B (6 0), pressure 2 K at the entrance of the metal to the rolls and p 2K -6., at the exit of the valps, and k - the limit of the fluid shear. The stress exerting not only on the stress state, but also changes the friction forces, in fact displaces the neutral section. This is due to the fact that (b F) is an external force; F is the area of the silver section on the metal exit from the rolls, changing the equilibrium condition as a whole. It is possible to provide the same neutral; e section of the NRP 6 O,) "SO, where 6D is the rear tension or back pressure. In this case, the plot-p (x) is shown by a dotted line: p - 2 K -i-Sg at the entrance to the rolls; P 2k at the exit pz rolls. Backfill;:; the axle reduces the rolling moment and power, by the specific pressure (with compressive stress b 0) increases. In general, the power is down. is. but to determine the degree of influence of each component does not represent}; TYUZMOLCHNE-F.

iic to the proposed method, internal equilibrium forces are applied to the workpiece, which do not change the equilibrium condition of the workpiece and therefore the pressure is reduced only due to a change in the stress state. In this case, the pressure p (x) (Fig. 6) at

6 About b About

1 o

, /

(one)

 billet cross section area before rolling.

By the known methods it is possible to apply equal forces to the deformation zone, but this is practically. it is impossible to ensure, as the speed fluctuations of the coilers, neighboring stands, the thickness variation, the deformation of the rolls violate this condition. At the same time, according to the proposed method, the equality of forces (with an accuracy of the amount of losses in the cylinder seals, oil viscosity and so on) is ensured as the equality of the forces of action and counteraction. & IG (x-1) and the hydraulic cylinder will do the work A (A-1), and it is precisely this value that y1-1enshits-with the rolling energy, and the capacities - from N "to N PV (L -1), where T is cylinder strength (beyond the reach of compaction resistances).

By the proposed method, the rolling power can be adjusted with high precision due to the force F and the pressure in the cylinder, Example. A pipe with a diameter of 150 mm, 5 mm thick, 2000 m long of aluminum is rolled at a temperature. The deformation is carried out in rolls with a diameter (at the bottom of a round caliber) 400 mm. A hydraulic cylinder is inserted into a hollow billet. The cylinder has an outer diameter of 120 mm, an internal 80 mm and a length of 1000 mm with a stroke of 800 mm. From the oil station to the cavity of the cylinder summed up the pressure to p 300 at. If p O and loading the workpiece is not performed, then the specific pressure

15

-2kb --- 1,156 tn

  , ,

 0.0815-g

ten

15

20

five

0

five

0

five

5j - yield strength at discharge

st.

The length of the arc of capture is t, the contact is on the area (0.75 d); R

i

and

 at

 VRih 2.45 cm; F 27.7 cm

rolling force T 2.256 -. If 6 160 MPa (1600 kg / cm), then PO 36 kN (3.6 t), M 0.5 45 kN CM - rolling moment,

one roll uJ -1- 2 angular velocity power Ijl kW.

The area of the internal cavity of the hydraulic cylinder 2 is equal to 0.785 d 50 cm and when creating a pressure of 50.0 atm, the tensile force of the billet P 25 kN (2.5 tons). Let the coefficient stretch

L, then the power of the hydrocylide is equal to

- N PV (-1) 0.61 kW.

The value of the rollers is reduced by 0.44 (44%) only due to the effect of internal tension.

In this case, the stress (axial) in the pipe is 10.6 MPa- (106 kg / cm),. Theoretically, at .TT4b6-g, the plastic flow will occur only under the action of axial tension, and the power supplied to the rolls ,, is zero , and Р 380 kN (38 tons), which corresponds to a pressure of 760 atm; it is enough to create voltages up to 0.5S.

The technical and economic advantages of the proposed method are that the deformation with internal tension, with the application of internal forces to the cage-procurement system, does not alter the equilibrium conditions and does not overload the cage drive, while the resistance to deformation of the workpiece changes. can be adjusted during the rolling process.

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Compiled by I.Skorobogatsky Editor L.Gratillo Tehred Q.CpnKOGreader A.Zimokosov

Order 3941/5 Circulation 518.

VNIZh1I State Committee of the USSR

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

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Claims (4)

1. METHOD FOR ROLLING Billets, including their deformation in rolls with tension, characterized in that, in order to improve measurement accuracy during experimental studies of the rolling process, two internal forces are applied to the workpiece to be deformed, directed along its axis and balanced on the workpiece itself . 2. The method according to π.1, characterized in that, in order to deform the prestressed workpiece, internal forces are applied before rolling. 3. Method As claimed in claims 1 and 2, characterized in that one of the balanced forces is applied alternately in different sections along the length of the workpiece. 4. The method according to claims 1 to 3, characterized in that the balanced _β- neck system of forces is applied simultaneously to several “g” at least two parallel billets. SU „„ 1245362 A1 1245362