SU763025A1 - Method of making ring-shaped products such as piston rings - Google Patents

Description

one

The invention relates to processing (lethal pressure, in particular to the manufacture of ring products such as iojjuiHeBHx rings by the rolling method.

A known method of manufacturing piston-5 rings, in which the shaping of the contour is carried out in three waves. Kami, of which two are fixed (supporting), and the third adjustable roller ensures bending of the workpiece 10 of the ring Cl.

The disadvantage of the known method of forming the ring contour is the principle impossibility of obtaining the calculated shape in the zone of the ends of the branches (the lock zone), since in this zone there is a under-ring, which follows from the way the method is implemented. Lacking the shape of the ring in the lock zone leads to a marriage, 20 since it turns out to hove or support the ends of the branches. In addition, this method does not solve the problem of obtaining a ring of a given shape.

There is also known a method of manufacturing 25 annular products by rolling a billet of measured length between two rotating in opposite directions rolls with a change in the ratio of their linear speeds 2.

However, with this method of manufacture, the bending of the workpiece occurs in a plane that runs along the rolling axis parallel to the shaft. The product has a spiral shape with a trapezoidal cross-section. The implementation of the formation of a piston ring like this. the method is impossible due to the need to obtain a rectangular section thereof.

The purpose of the invention is to improve the accuracy of the geometric shape and size of the annular products.

The goal is achieved by the fact that the change in the speed of the rolls takes place along the length of the workpiece in the following ratio

H n

Vn

2p (y) -t

where V .. L is the linear velocity of the corresponding

first and second rolls;

-radial thickness of ring. product;

Pt)

-radius of curvature of the annular product depending on the angular coordinate of the current section of the workpiece;

(S) Angular coordinate (central angle) of the current cross section. no billet.

FIG. 1 shows the rolling of a ring blank between two rollers; in fig. 2 - an element of a piston ring in the deformation zone, as shown in the words of the derivation of the formula for the ratio of linear speeds of the rolls.

A blank ring 1 of measured length is fed into the solution between two rolls 2 and 3 rotating in opposite directions, where it is crimped and, due to the difference in tangential forces determined by the difference in linear speeds of the rolls, the bend of the blank is bent, and its curvature depends on ratios of linear velocities of the rolls in the deformation zone.

From the set-up element of the piston ring in the deformation zone follows

ds + as ptV} + d4

(1) ds p (.4) (2)

Differentiator (1) and (2) in time and taking into account that dS / dt is the speed, after the conversion we get

(RM-s |}

(3)

H

d

VH (P () - i-)

. with)

ar

to (4) and the situation in relation to (3) the Vedas of transformation finally we get:

V 1. U

(five)

Vu 2p (4) -t

Since in (5) on the right side, t is a constant value for specific rings, and p () is the radius of curvature in the general case is variable and depends on the angular coordinate S of the deformation zone, the ratio of linear velocities VI / MT is a function of W. Formula (5) outlines the dependence of the ratio of the linear velocities of the rolls on a given function of changing the radius of curvature p (h) of the piston ring.

Example. Calculate the linear speeds of the rolls to form a ring with a uniform plot of reel: .0.01 kg / mm2 f M RO Ð PO (1 + cosf) kg. Mm - square profile cross section: b 1 2 mm, L Ring-salted material (E 20000KG / m f). Nominal diameter p 62 mm (on the neutral line),. The speed of the second roll is constant and equal to 50 mm / s. The function of changing the radius of curvature p (h) is obtained from the basic bending equation of a curved beam that st

Substituting here the given values of na. dimensions, we get

5 4..cosv) 7)

.Substantial value (H) in formula (5) we finally have

W cnfi4. in Qoasau io Q V, 50 (1+ i- | bo8i + 8ico & 4

Formula (8) defines the function of varying the speed of the first roll, depending on the angle of rotation of the workpiece, in order to obtain the specified ring

5 forms.

The use of the proposed method of manufacturing annular billets such as piston rings compared to existing ones provides the following

j, advantages: improving the accuracy of the geometric shape and size of the annular products; reduction of labor intensity and cost of manufacture of products due to simplification of the technological process; the possibility of using a wide range of materials for the manufacture of products; stability of obtaining rings with specified parameters; automation of the manufacturing process of ring products.

Claims (2)

1. The patent of France 2181406, cl. F 16 I 9/00, 1973. 2. USSR author's certificate number 429872, cl. B 21 D 1/06, 1972.