SU1648737A1 - Method for machining thin-walled members - Google Patents

Abstract

The invention relates to the processing of metals by pressure, relates to the plastic deformation of thin-walled parts and can be used in the manufacture of gaskets for sealing assemblies in pneumatic-hydraulic systems. The aim of the invention is to increase the reliability of the gasket in the sealing assembly. A thin-walled C-shaped gasket is attached to the replaceable inserts of the mandrel, which is clamped with n / side, driven by a screw pair. Then, the gasket is deformed plastically using a diamond indenter, and the deformation force along the length of the forming voltage is the timing of its work Plastic deformation under this law allows to improve the reliability of the upper part of the leg due to the fact that the distribution of metal The gasket will have a characteristic distribution of stress intensity and, as a result, during operation, the elastic-plastic deformation will occur simultaneously along the entire length of the gasket. 2 Il (L

Description

The invention relates to the processing of metals by pressure, in particular to the finishing and hardening treatment by diamond smoothing, and can be used in the manufacture of C-shaped gaskets sealing assemblies.

The aim of the invention is to increase the reliability of the gasket in the sealing assembly by increasing the contact pressure,

FIG. 1 shows a diagram of a device for diamond smoothing C-shaped seals; in fig. 2 - stress intensity distribution (a) and deformation force (b) along the length forming the gasket

The device for implementing the proposed method is made in the form of a mandrel containing interchangeable liners 1, working

the surface of which is equidistant parts of the processed C-cut gasket 2, installed on these inserts 1 The mandrel also includes clamps 3, spring-loaded relative to the inserts and installed with the ability to move relative to the body 4 when using the 5th Diamond Indentation 6 is mounted to longitudinal and transverse movement relative to the mandrel with a gasket fixed on it 2

about

00 h |

00

vl

The method is implemented as follows.

The diamond indenter 6 is smoothly brought into contact with the gasket 2 in the area separated from its end by an amount equal to 0.1, 0, 2 of the length of the generator with the force Py, and then deformed according to the law

Z

Py vЈfTe 2 The specified law of deformation is necessary to obtain a gasket with optimal performance characteristics (combination, stiffness and elastic characteristics). With such a deformation, the yield strength of the material Or is distributed similarly to the intensity of the stresses of the material of the gasket 2 when it is loaded with a sealing load during assembly and operation. On the plot of the strip 2, equal to 0.8; - 0.9 times the length of the generatrix, the indenter b is smoothly removed from contact with the gasket 2. Before the deformation, for this gasket 2, the stress intensity distribution in a longitudinal section is calculated using a finite-element method,

In the formula that determines the force of deformation, the value

Z K (| Ј-0.5 |) n,

where X is the current coordinate of the forming strip,

0, 9b,

b is the length of the outer forming cross section of the gasket, mm

Kip-coefficients depending on the shape of the seal.

Example. For gasket 2, made of steel 12X18H10T with the following geometrical parameters: gasket height H 10 mm; average radius Rs 9 mm: seating diameter of the gasket D 74.7 mm, wall thickness of the gasket S 0.8 mm, using the finite element method, calculate the stress intensity distribution in longitudinal section with a sealing load. Thereafter, a C-shaped gasket is installed on the mandrel and deformed. In determining the dependence of the force of deformation of Ru on the length

generators b use regression control that binds the yield point from with the hardening treatment modes

In this case, the coefficients A, K. p in formulas (1) and (2J, respectively, are equal to:

A ЈTG Rutah 250 626 N,

K 15 n 2.

The longitudinal feed of the indenter 6 during processing is 0.5 mm / rev. The radius of the sphere indenter RSF 1.2 mm.

The proposed solution improves the reliability of the gasket by increasing its elastic and stiffness characteristics.

Claims (1)

Invention Formula A method of processing thin-walled parts in which plastic deformation of a rotating part is carried out with force by means of a tool that is reported to feed and reciprocating movement along its own axis in the direction of the surface to be machined, characterized in that, in order to increase the reliability of the work of parts of the gasket in the seal assembly by increasing the contact pressure, during processing, the deformation force varies along the length of the forming part according to the law -Ј 2 and in the minimum cross section of the part, it is increased to the maximum value, while plastic deformation of the part is carried out in the middle part, which is 0.1 to 0.2 times the length of the generatrix part from the end edges, where Py is the deformation force, A is the coefficient depending on the material of the part; e is the base of the natural logarithm; Z is variable, depending on the coordinate of the generator. / 2