SU978991A1 - Railway wheel rolling method - Google Patents

Description

The invention relates to the processing of metals by pressure and can be used in the manufacture of iron for road wheels.

There is a known method of rolling railway wheels from molded blanks by rolling a rim along its outer and side surfaces and subsequent rolling of the rim with a disk with core and pressure rollers along the diameter with a gradual decrease in the specific reduction force of the pressure roll C 1.

When the parameters of the workpiece deviate (temperature of heating, mass, composition of metal, etc.), the wheel flange underpowers, as the rolling of the rim with the disk in diameter at high pressure (150-160 kg / cm) occurs faster than rolling the rake, resulting in the ridge is produced by increasing (by 2-3 turns) the polishing period under reduced (up to 55–60 kg / cm) pressure in the hydraulic cylinders of the pressure rolls. At the same time, the reduction of the rim decreases to 0.4–0.8 mm per revolution, which allows In some cases, the child may be rolled up, but significantly (by 2-3 seconds) in magnifies

rolling time and reduces the productivity of the mill. In addition, long-term polishing reduces the accuracy of the geometric dimensions of the rim of the wheel due to the additional rolling of the rim with the disc diameter.

The aim of the invention is to improve the quality of the wheels.

ten

To achieve the goal when rolling rail wheels from molded blanks by rolling a rim on its side and sides and then rolling

15 rims with a disc and corners and pressure rolls in diameter, with a gradual reduction in the specific reduction force (pressure rolls, before reducing the specific reduction force in the press rolls, gradually increase the specific reduction force in the native rolls during 1.2-1 turn from 55-60 to 80-90 kg / cm and hold it for 3-4 wheel revolutions, 25 and then reduced to 55-60 kg / cm in 4 revolutions.

The drawing shows the scheme of compression of the wheel rim.

The side surfaces 1.2 of the rim 30 and the inner surface 3.4 of the rim.

The inclined rollers 5,6 are mounted on the end of the wheel; a pressure roller 7 is installed; the surface is machined by satany, driven by a hydraulic cylinder 9. On the opposite side of the wheel, a main roller 11 is mounted on the carriage 10; 13 and supporting valve 14 (for example, safety ;.

The essence of the method lies in the fact that the formed billet is set into a wheel rolling mill and within 2.5-3 revolutions, the rim is punctured over the surface 8 and lateral 1, 2 surfaces at the pressure of the working fluid in the hydraulic cylinders 12 of the carriage 10 7} roll of 55-60 kg / cm. Then increase the specific pressure of the pressure rolls, lift the pressure in the hydraulic cylinder 9 to 150-160 kg / cm, and roll the rim with the disc in diameter with a constant pressure for 67 turns, after which the specific rolling pressure gradually, over 3-4 turns, reduced by reducing the pressure in the hydraulic cylinder 9 to 55-60 kg / cm, while 1-0.5 turns of the workpiece before the pressure begins to decrease increases the specific force of compression of the main roller 11 to the wheel rolling surface 8, for which increase the pressure of the working fluid in the hydraulic cylinder 12 to 80 90 kg / cm and hold for 34 revolutions of the workpiece, then reduced to 55-60 kg / cm When this occurs, the redistribution of forces in the deformation zone. The specific pressure on the inner 3.4 and side 1.2 surfaces of the wheel rim is reduced, and the pressure of the pressure roll 7 on the wheel roll surface 8 remains sufficient to ensure reliable rolling out of the ridge together with the main roller 11. At the same time, as the rolling pressure decreases, the inner 3.4 and side 1.2 surfaces of the wheel rim are polished, which makes it possible to shorten by 1-2 s the rolling time by combining operations and to obtain the optimum geometrical dimensions of the roughing wheel. The final adjustment of the geometric dimensions is continued by polishing, for which the wheel is rolled for 2.5-3 revolutions with the pressure of the working fluid in the hydraulic cylinders 11 and 12, equal to 55-60 kg / cm.

An example of the method, pre-heated to 1241260s and molded on presses were set in the wheel rolling mill

force 2000, 5000 and 10000 ton / billet of wheel steel weighing 460-475 kg.

The process of rolling a wheel can be divided into four steps,

At the first stage, when the pressure of the working fluid in the cylinders of the pressure roll and the carriage movement of 60 kg / cm, the rim was rolled along the outer and side surfaces in

2.5, -3 wheel speed.

In the second stage, the pressure in the hydraulic cylinder of the pressure rolls was raised to 155 kg / cm, and the rim with the disc was rolled in diameter to the size

745 mm for 7 Turns of the wheel. At that, the pressure of the working fluid in the hydraulic cylinder for moving the carriage remained equal to 60 kg / cm, and as the diameter was rolled, the liquid was squeezed into the line. Before the end of the stage, 1–1.5 revolutions before the pressure began to decrease, the piston cavity of the hydraulic cylinder for moving the carriage was locked by switching the distributor to the neutral position. The pressure in the piston cavity was increased to 85 kg / cm and was maintained with the help of the valve 14 for 3-3.5 turns, At

This increased the intensity of rolling out the ridge.

At the third stage, the pressure of the fluid in the hydraulic cylinder of the pressure rolls gradually, during 4 wheel revolutions, was reduced to 60 kg / cm and the rim was rolled with a disc in diameter to a size of 798-799 mm with an intensive ridge roll.

At the fourth stage, by switching the distributor 13, the piston cavity of the hydraulic cylinder moving the carriage to the main line was connected and polishing was performed at a pressure of 60 kg / cm - the rim was rolled with a disk in diameter to a size of 800 mm with simultaneous finishing of the remaining wheel geometries.

The economic effect from the introduction of this method (according to the data of the plant named after Liebknecht) will be:

1) Expected annual production of wheels on the new line in 1980:

26.14 x5825 152300 (pcs.),

where 26.14 is the actual hourly productivity for 1979 by the new line, t / h;

2) Growth in production with an increase in hourly productivity by 2.5%:

152300x1.025-152300 156100-152300 3800,

H; The expected annual economic effect, taking into account the investment investment of 20,000 rubles.

31.80x3800-I 0.15x20000) 117840 rub. where 31.80 - conditional-fixed costs for the workshop according to the plan for 1980;

0,15 - the coefficient of efficiency of investment.

 the invention

The method of rolling rail wheels from molded blanks by rolling the rim along its outer and side surfaces and then rolling the rim with a disk with core and pressure rolls along the diameter with a gradual decrease in the specific force of curling rolls, in order to improve the quality of the wheels, by reducing the specific force of compression of the pressure rolls, the specific force of compression of the indigenous heads is gradually increased during 1 / 2-1 turn from 55-60 to 80–90 kg / cm and held for 3-4 days. then reduce the wheel to 55-60 kg / cm over 4 turns.

Sources of information taken into account in the examination

1. USSR author's certificate 721201, cl. 21 H 1 / 01.07.07.78 (prototype).

Claims (1)

Claim The method of rolling railway wheels from molded billets by rolling the rim along its outer and lateral surfaces and then rolling the rim with the disk by root and pressure rolls in diameter with a gradual decrease in the specific compression force of the pressure rolls, characterized in that, in order to improve the quality of the wheels, a decrease in the specific force of compression of the pressure rolls is carried out 5 a gradual increase in the specific force of compression of the main rolls during 1.2-1 turns from 55-60 to 80 90 kg / cm ² and hold it for 3-4 turns of the wheel, after which 10 reduce to 55-60 kg / cm ² over 4 turns.