SU1514506A1 - Method of vibration drilling of deep bores - Google Patents

Description

The invention relates to metal cutting, in particular to methods of machining holes in parts made of viscous high-alloyed steels. The purpose of the invention is to increase

2

performance of the drilling process by eliminating the oscillatory movements of the tool. Parts 1 report rotational motion, and tool 2 - feed movement and axial oscillations. With the help of the above movements, the process of intermittent cutting is carried out within the limits of the thickness of the cutting layer C _{and the} material of the part. A pulsed flow of cutting fluid under pressure P is supplied to the treatment area. At the same time, axial oscillations synchronously in phase are carried out, which impose on the feed movement and pulsating flow of coolant, and also combine in time the maximum amplitudes of the latter and the axial oscillations of the tool. 3 il.

with

(rig!

1514506 A1

³ ) 51 ^ 506

The invention relates to the processing

metals by cutting, in particular, to methods for machining holes in details

from viscous high-alloy steels. $

The purpose of the invention is to improve the performance of the drilling process by eliminating the oscillatory movements of the tool.

Figure 1 shows the contact area of the cutting blade of the drilling head with the forming chips and the surface of the part; FIG. 2 shows harmonic oscillation curves for axial movements of the tool and change in pressure of the flow of coolant supplied to the blade cutting zone; FIG. 3 shows another dependence of the oscillations of the tool and the pressure of the coolant — 20, at which the coincidence in time of their maximum magnitudes of the amplitude values alternates.

During machining, parts 1 report relative rotation (A, and .25 to tool 2 - feed movement 5 and axial oscillations 8, which carry out the process of intermittent cutting within the thickness of the cutting layer c _and material of part 1. Supply lubricant-30 but cooling fluid ( The coolant in the area of contacting a and B of the cutting blade of the tool 2 with the workpiece surface 1 is performed with a harmonically varying pressure of 35 P in the cutting zone of this tool 2. At the same time, · axial oscillations synchronous in phase are carried out, which s is applied to the feed motion 8 and a pulsation pressure P coolant to the maximum amplitude of A _p and A _yn are aligned in time. A plot of the harmonic oscillations for varying values of tool vibrations and protection for the case of interruption 45 whist cutting is shown in Figure 2.

The harmonic law of variation of the oscillation of the instrument is represented by the curve D, and for the pulsating pressure in the form of the curve K. The displacements of the maximum amplitudes A _p and A „ _n in phase on this graph are equal to zero, i.e. fair dependency

H>

e - · = - -t and ω with + = O,

ω ₅₅

where u 'is the oscillation frequency, measured by the number of radians per second;

С - the time after which the movement of the variable parameter of the instrument or

pressure flow coolant repeat2ΪΓ

ryta and is equal to = 7;

Wed is the phase of the considered parameter changes.

At the same frequency, the dependence for the tool oscillations is defined as

Υ, = A _in δίη ω 's,

and for the flow pressure of the coolant in the cutting zone of the cutting blade is assigned from the dependency, which in general has the form

At _r = Ap 8ΐη (ω 'с + Ч>).

Practically, another cycle of tool oscillation and coolant pressure (FIG. 3), which is for curve I, which characterizes the pressure change, can be implemented as a result of imposing a constant flow pressure on the coolant pressure pressure, which changes according to a symmetric law, and curve II The full period of oscillation of the cutting tool is the actual process of cutting the cut in a very short period of time. This nature of the change in the thickness of the cut and, accordingly, of the cutting forces can be realized when the tool oscillates with a frequency q), an amplitude A of _them and a cutting speed not exceeding the value of 2ί? Α „ _Η ω.

The effects of simultaneous effects of variable magnitudes of tool oscillations and coolant pressure are superimposed on the effects associated with improved chip breaking conditions due to forced division along the length, as well as with a more even distribution of heat transfer from the cutting zone to the coolant used, to which the proportional increase in cut thickness fully corresponds to the amount of incoming environment.

Claims (1)

Claim The method of vibratory drilling of deep holes, in which relative movements of rotation and axial movement are reported to the tool and parts, axial oscillations are imposed on the latter and coolant is supplied to the treatment area, characterized in that 6 that, in order to improve performance, coolant serves a pulsating flow, and the ripple flow is combined in phase 4506 with the axial oscillations of the instrument, and the maximum amplitude of the latter in time is combined with the maximum 5 amplitude ripple flow.