RU1798144C - Device for blasting articles - Google Patents

Abstract

Usage: the invention rtnosits to surface treatment with a strong jet of air, basin or liquid with suspended grains of sand or grains made of abrasive material, and can be used in mechanical engineering as a nozzle of sandblasting machines. SUBSTANCE: in order to increase the processing efficiency, a swirl is arranged inside the nozzle, made in the form of a sleeve covering the outer surface of a thin-walled tube for supplying a processing medium. The swirler occupies the entire volume of the nozzle slit, and on the outer surface of the sleeve there are helical holes. The ratio of swirl length to diameter is less than 0.5 or greater than 0.2, and the angle of inclination of the grooves along the length is 4-5 °. . 3 silt;

Description

The invention relates to surface treatment using a strong jet of air, gas or liquid with grains of sand or grains suspended from them made of abrasive material, and can be used in mechanical engineering as an auxiliary device for sandblasting machines, namely nozzles for them.

The aim of the invention is to improve the processing efficiency due to the dynamic components of the kinematic parameters of the energy carrier;

In FIG. 1 shows a device for

jet processing of products; in FIG. 2. swirler; in FIG. 3 - speed plan for

unified energy flow at

expiration through a nozzle with eavichritel.

The device for blasting products according to the invention comprises a conical nozzle 1 with a coaxially thin-walled tube 2 placed therein for supplying a processing medium. The narrowing part of the conical nozzle forms a nozzle 3. A thin-walled tube 2 through the connection 4

and a fastening sleeve 5 in the form of an elastic sleeve is connected coaxially with a channel 6 into which a processing medium is supplied through a nozzle 7. The fitting 8 in the device case 9 serves to supply energy to the conical nozzle 2 and the nozzle 3. The device body 9 covers a fastening device 10 with a handle 11. In the nozzle 3 of the conical nozzle 1, a swirler li is made, in the form of a sleeve covering the outer surface of the thin-walled tube 2 with helical grooves on the outside. . .

In FIG. 3 is indicated; Vm is the meridional velocity of the energy carrier through the gap; R

V is the radius of the swirl channel 12; Wm Coriolis energy velocity through the gap; Vu is the tangential component of the energy velocity at the exit from the slit; V - rounded flow rate of the energy carrier at the exit from the gap; a arctg-rr -

vu the angle of inclination of the ribs of the swirler in length;

Joint venture

WITH

Xi

H)

00

S-

W is the meridional Coriolis flow velocity of the energy carrier at the exit from the gap; Wu is the tangential Coriodis velocity of the energy carrier flow at the exit from the gap; Uu is the tangential velocity of the energy carrier exit from the gap.

The proposed device operates as follows. .

The flow of energy through the nozzle 8 is fed into the body of the device 9 and through the channel of the conical nozzle 1 — into the nozzle 3, passing through the screw grooves 13 of the swirl 12 forms static compliance due to the pressure drop across the input and output from it and dynamic compliance due to the difference pressure. :

Po-pk-s ..,. ... (1) L

.. 2.. ..:. -..-

where S-tr is the velocity head of the energy carrier flows in the longitudinal longitudinal helical ribs. 13. swirl 12; . .. .., .-.;.

Po - inlet pressure swirl

12 .,: .. - : : . ::

Pk is the pressure after exiting the swirler 12 inside the flow of the energy carrier and the processing medium. .. .- -: .. That is, concentrated compliance is formed; .-. :. dVn „d FKCP FTL d.Ki

(2)

d.Pr d.Ki. Po -Pk where Vk is the volume of the energy carrier flow, at the outlet of the swirler.;

Pi- energy pressure at the output of the swirler 12; -: -.

Pi - Pk K .-- rNA

FKCP cross-sectional area. exit nozzle 3;

FT is the averaged cross-sectional area of the west of the scaler 12;

L is the length of the swirl.

In addition, an additional gradient of Static compliance is formed due to the twisting of the energy carrier flow in the swirl 12: 1 d S

d4n (3)

Pi COS2 d R R Vm COS

XJ 4z VmX

xsin cos

where S is the chargeability of the energy carrier flow, 1

XP is the angle between the direction of the Coriolis velocity and the axis of the coaxially located nozzles 3 and the thin-walled tube

2; ...-, /. -: ..-. /:. Z is the length of the stream of energy flow. Based on the expressions according to formulas 1, 2. 3. substantiating the dependence of the velocity potential in the interaction

of plane and axisymmetric flows of energy carriers and their parameters, as well as the relationship between changes in the cross section of the current tube and flow velocity in the compress: the fifth energy carrier (gas, liquid) obtain a plan of the velocities of the outgoing energy stream, as shown in FIG. 3. This stream, fed through a nozzle 3, discharges in the direction of the product: forming a processing medium, arriving at. nozzle through fitting 7, connection 4, channel b and thin-walled tube 2 .:;

Thus, the resulting flow of energy and processing medium

|; 5- has improved energetic character of christics due to the dynamic components of the energy carrier flow, in addition, the distance of the flow passage increases with the necessary: its energy, dl.

.20 product processing ..: .-. :. .. .- At the same time, the swirl is performed with a ratio of length L to diameter D less than 0.5 or greater than Q.2, which; allows to optimize losses of the 25th head and at the same time increase

 spin flow. The angle of inclination of the ribs 13. for .. vortices 12 along the length L (Fig. 26) is 4-5 ° w, this allows to reduce the loss of velocity head and to increase the flow rate coefficient by 2 times. . ; ... .. These conditions make it possible to stabilize the parameters of the energy carrier flow and eliminate stalls and pulsations. -.--. . ; ; The proposed device provides

35 improving the quality of processing, reproduc. the conductivity of hardening results and the improvement of the hardening conditions for products by improving the law of distribution of quality indicators (process energy, speed:

40 sti and acceleration of the flow, flow path.) Process. :. . . ::::; :. Formula and sampling -. : - A device for blasting products containing a nozzle for supplying energy.

45 carrier with coaxially mounted in :. a thin-walled tube for supplying a processing medium with a fastening element in the form of an elastic coupling, which is further included in order to increase the processing efficiency, the device is equipped with a swirl made in the form of a sleeve with screw grooves on the outer surface mounted on a thin-walled tube

55 of the outer surface with an inner surface

 the specificity of the nozzle, while the ratio of the length of the sleeve to its outer diameter is selected within 0.2, 5. and the angle of inclination of the helical grooves is 4-5 °.