INVESTIGATION RESULTS PERTAINING TO DETERMINATION OF REVERSE FLOW PRESSURE ON TREATED FLAT SURFACE

The executed investigations have shown that it is possible to prepare sheet-like material for laser cutting economically viable and with small amount of power expenditure while using reverse jet cleaning for surface treatment. As compared to conventional jet cleaning technologies efficiency of the reverse jet cleaning is attributed to significant pressure increase (by 25–50 %) when the jet is interacting with the treated surface. The paper proposes a mathematical model on the basis of approximate energy method (upper-bound method) and the model is used for calculation of fracture pressure due to action of the reverse jet on the treated surface which consists of a corrosion deposit layer. A variational problem was solved within a framework of the developed model and the problem solution has made it possible to obtain a theoretical dependence for calculation of minimum fracture pressure value p_min in the point reverse jet impact with a barrier oretical dependence and it has taken into account yielding point of the deformed material ss, density of fractured material med material r, jet velocity u_стр and parameter of reverse flowing – jet reduction ratio l. Comparison theoretical data and experimental ones (experimental data have been obtained while using a differential pressure transducer ЭДП-30 and a spring dynamometer with measuring limits 25 and 80 MPa, respectively) has shown difference by 4–15 %. Determined insignificant difference between a theory and an experiment demonstrates that the obtained theoretical dependence is considered as a quite correct one and it can be used in engineering practice for prediction of power and kinematics parameters which are necessary for selection of the required pump equipment designed for realization of reverse-jet cleaning process.

1. Kachanov I. V., Zhuk A. N., Shatalov I. M., Shariy V. N. (2015) Device for Corrosion Removal From Flat Steel Surface. Patent Republic of Belarus No 19453 (in Russian).

2. Kachanov I. V., Zhuk A. N., Shatalov I. M., Shariy V. N. (2010) Device for Corrosion Removal From Flat Steel Surface. Patent Republic of Belarus No 16526 (in Russian).

3. Zhuk A. N., Kachanov I. V., Filipchik A. V. (2017) Technology of Reverse-Blast Corrosion Cleaning of Steel Sheets Prior to Laser Cutting. Nauka i Tekhnika = Science & Technique, 16 (3), 232–241 (in Russian). DOI: 10. 21122/ 2227-1031-2017-16-3-232-241.

4. Kachanov I. V., Filipchik A. V., Babich V. E., Zhuk A. N., Ushev S. I. (2016) Technology of Hydroabrasive Blasting for Corrosion Removal and Protection Against Corrosion of Steel Products While Using Bentonite Clay. Minsk, Belarusian National Technical University. 167 (in Russian).

5. Rabotnov Yu. N. (1988) Mechanics of Deformable Solid Body. Moscow, Nauka Publ. 654 (in Russian).

6. Tomlenov A. D. (1972) Theory for Plastic Deformation of Metals. Moscow, Metallurgiya Publ. 408 (in Russian).

7. Kachanov I. V. (2002) Speed hot Extrusion of Rod-Shaped Products. Minsk, Tekhnoprint Publ. 327 (in Russian).

8. Storozhev M. V. (1977) Theory of Pressure Metal Treatment. Moscow, Mashinostroenie Publ. 420 (in Russian).

9. Frenkel N. Z. (1956) Hydraulics. Moscow, Mashinostroyenie Publ. 455 (in Russian).

10. Kachanov I. V., Zhuk A. N. (2015) Experimental Investigations on Determination of Pressure Force of Power Fluid-Jet Stream on Plane Surfaces of Specimens Having Various Shape. Nauka i Tekhnika = Science & Technique, (3), 30–36 (in Russian).

11. Kachanov I. V., Zhuk A. N., Yaglov V. N., Filipchik A. V. (2014) Composition of Working Liquid for Hydrodynamic Corrosion Removal From Metallic Surfaces Prior to Laser Cutting. Patent Republic of Belarus No 21455 (in Russian).

12. Kachanov I. V., Zhuk A. N., Filipchik A. V. (2016) Method for Cleaning Metallic Surfaces: Patent Republic of Belarus No ?20140350 (in Russian).

13. Gavrilko V. M. (1985) Filters of Drilled Holes. Moscow, Nedra Publ. 455 (in Russian).