SU1656275A1 - End fittings for high-pressure hoses - Google Patents

Abstract

The invention relates to engineering hydraulics, in particular to high pressure hoses, and is intended for use in the hydraulic systems of tractors, agricultural and road machines and in other parts of the national economy. The purpose of the invention is to increase reliability. The high pressure end fittings comprise a hose, a nipple and a sleeve. On the outer surface of the coupling there are annular projections that coincide in location with the projections on the inner surface of the coupling, and the dimensions of the projections are determined by the following relations f DB - DM 2f: f dM - dB Knl4 2f; L (2.5 - 3.5) c; f Ј3Lj; 6dn where DB is the outer diameter of the projections; DM is the outer diameter of the coupling; de is the internal diameter of the protrusions, dM is the internal diameter of the coupling; f is the deformation of the outer diameter of the coupling; q is the specific pressure on the clutch during the reduction process; I is the distance between the extreme points of two adjacent projections; E is the modulus of elasticity of the material of the coupling; J is the moment of inertia of the coupling; L is the step of the protrusion; b is the protrusion width; dn is the diameter of the winding wire of the hose; K is the coefficient characterizing the design features of the end fittings of the high pressure hose, K 400-450. 3 il. J

Description

The invention relates to engineering hydraulics, in particular to high pressure hoses, and is intended for use in the hydraulic systems of tractors, agricultural and road machines and in other sectors of the national economy.

The purpose of the invention is to increase the reliability of the connection of the end fittings to the hose and to prevent pinching of the inner rubber layer.

FIG. 1 shows the end fittings of a high pressure hose, a longitudinal section; in fig. 2 is node I in FIG. one; in fig. 3-end high pressure hose fittings before crimping, longitudinal section.

The end fittings of the high pressure hose consist of a coupling 1, on the outer surface of which there are protrusions 2 that coincide in location with the projections 3 on the inner surface of the couplings, the nipple 4 and the hose 5 with the outer rubber layer removed.

In the process of compressing the end fittings with a hose, the device operates as follows.

At the initial moment of crimping, the contact of the coupling 1 with the hose 5 occurs only along the tops 6 of the internal projections 3. As the specific pressure q influences the projections 2 on the outer surface of the sleeve M

o you ate

You 1, in the process of crimping, the coupling 1 with the hose 5 contacts also with the side surfaces 7 of the inner projections 3, and then completely along the inner recesses.

The dimensions of the protrusions are determined by the following ratios:

f DB - DM 2f; i bm dB

 2f; L (2.5 - 3.5) c; f;

L. j

3dn b 6dn where DB is the outer diameter of the protrusions;

DM outer diameter of the coupling;

de inner diameter of the projections;

dM is the internal diameter of the coupling;

f is the deformation of the outer diameter of the coupling;

I is the distance between the extreme points of two adjacent projections;

E is the modulus of elasticity of the material of the coupling;

J is the moment of inertia of the coupling;

L is the step of the protrusion;

b is the protrusion width;

dn is the diameter of the winding wire of the hose;

K is the coefficient characterizing the design features of the end fittings of the high pressure hose, 450.

The protrusions on the outer and inner surfaces of the coupling: made height

RR Rm- and. When crimping end

The reinforcement outer diameter of the coupling is reduced by an amount f that exceeds the height of the protrusion of the outer diameter of the coupling in order to avoid deformation of the outer diameter. Projection width 3dn b 6dn. Thus, the protrusion is in contact with at least windings of the winding wire of the hose.

As a result of compression, the contact occurs over the entire surface F of the internal projections 3 of the coupling 1. At the same time, due to the increasing contact area of the internal surfaces of the coupling with the hose, during the reduction, the specific pressure on

the inner rubber layer of the hose is reduced ..

A further increase in the specific load q leads to plastic deformation of the projections 2 on the outer surface of the coupling, and no force is transferred to the inner rubber layer of the hose.

Claims (1)

The formula of the invention The end fittings high sleeves pressure, the hose, the nipple and the coupling with its subsequent compression in the zone of power seals, the sealing zone and the zone of unloading from bending moments, which is different in order to increase reliability of the hose connection with the end fittings; on the outer surface of the coupling there are annular projections that coincide in position with the projections on the inner surface of the coupling, and the dimensions the protrusions are determined by the following ratios: f DB - DM 2f; f dM - dB 2f; L (2,5-3.5) B; f where D8 is the outer diameter of the protrusions; DM is the outer diameter of the coupling; de is the inner diameter of the protrusions; dn is the internal diameter of the coupling; f is the deformation of the outer diameter of the coupling; q is the specific pressure on the clutch during the reduction process; I is the distance between the extreme points of two adjacent projections; E is the modulus of elasticity of the material of the coupling; J is the moment of inertia of the coupling; . L is the step of the protrusion; b is the protrusion width; dn is the diameter of the winding wire of the hose; K is the coefficient characterizing the design features of the end fittings of the high pressure hose, K 400-450.