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PROFESSIONAL ADVICE PROFESSIONAL ADVICE

SELECTION OF COOLING MIXTURE FOR
Note: in addition to taking into account the machine’s operating time, the logbook reflects
information on maintenance work (excluding those included in this section) and repair. METALWORKING OF AVIATION MATERIALS
Aviation materials include alloys such as low-
AFTERWORD carbon chromium-nickel steels, titanium and
In addition to surface grinding machines (originally from aluminum alloys. The reason for the widespread
the last century), other exclusive grinding use of these materials in the aircraft industry is
machines, in particular circular grinding their technological properties:
machines of the 3B12 type and 3K227A brand ● for aluminum alloys - low density (2.7 g
grinding machines, are also present on the / cm3), high strength characteristics, good heat
grinding sections of our machine-building and electrical conductivity, manufacturability,
enterprises. Both types of these machines are corrosion resistance, high ductility;
united by the same lack of any systematic ● for titanium alloys - high melting point, electrical
approach to the organization of planned resistance, strength, corrosion resistance, non-magnetic,
preventive maintenance by the management low density (4.5 g / cm3);
of the workshops (production sites). There are ● for chromium-nickel alloys - the ability to
objective reasons for this, the first of which is resist deformation and fracture under the influence
the level of production culture that remains low The following requirements are of mechanical loads at high temperature.
in comparison with the Soviet period. Another reason is the lack imposed on the metalworking process of
of qualified production technologists who have basic training in aviation materials [1]:
this type of already obsolete machine tools. ● high precision machining and low
Therefore, in the case of a hypothetical transition of the roughness;
work of our machine-building enterprises to mobilization rails, ● high productivity and exclusion of
there will be a problem of a qualified prize-winner behind the finishing work;
operating mode of grinding machines ● low sensitivity to the spread of
based on recommendations of their mechanical properties and geometric
operational documents. In addition, dimensions (variety of grades of tool
it is now impossible to quickly find a material);
trained grinding operator focused on the ● relatively low tool cost.
operation of these obsolete machines. However, the processing of these
Perhaps the necessary personnel will materials causes significant difficulties
have to be prepared without their associated with their high viscosity and
separation from production. low thermal conductivity, which leads to
For such possible circumstances, the formation of growth, overheating of
the system of operation of machine tools of the last century, the cutting tool, and a decrease in the
based on the already forgotten principles of the culture of durability and quality of the machined
production of the time in which these machines were produced, part.
should be established at the production sites of enterprises. The use of modern machine tools, tools with wear-resistant coatings and the supply of

V.P. Baranov, mechanic. cooling mixture to the cutting zone does not always provide the required quality and productivity
parameters. However, today metal cutting machines meet the requirements of accuracy. The
proposed tool range and the results of numerous studies make it possible to select such cutting
inserts, the use of which maximizes productivity and quality of processing.
At the same time, despite the development of a large number of coolant grades and testing in
this area, there is no single methodology that ensures the selection of the most effective cooling
mixture. The selection of an effective grade of it, according to available data [2], allows to
reduce cutting forces by 20%. Therefore, it is advisable to develop a methodology that ensures
the selection of such a brand.
In the general case, coolant mixture exerts lubricating, cooling, washing, dispersing,
cutting, plasticizing and other actions on the cutting process. However, by definition, the main
functional actions of the coolant mixture are lubricating and cooling actions. Therefore, the
development of methods for selecting effective coolant should be based on studies of these
actions.
References: Study of the lubricating effect of coolant
1. Operation manual for surface
grinding machine BRH 20A II. Lubricating effect is evaluated according to the test results both on the metal-cutting
Czechoslovakia, 1986. machines themselves during processing and on friction machines. The use of friction machines
2. Popov S.A. Grinding work. Textbook allows not only to reduce the consumption of materials, the coolant mixture itself and the time
for SPTU, M .: Higher school, 1987.
3. Kashchuk V.A. Handbook grinder. M.: spent, but also to exclude the influence of other actions. Therefore, the lubricating effect of the
Mechanical Engineering, 1986 coolant mixture in this work was evaluated by the results of tests on a friction machine. Figure 1

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