V.S. Burlakov, Y.N. Litvinov
Belgorod State Agricultural University named after V. Gorin, ul. Vavilova, 1, pos. Maiskii, Belgorodskii r-n, Belgorodskaya obl., 308504, Russian Federation
Summary. The low efficiency of some technological processes of silkworm breeding is accounted for the absence of the means of mechanization and automation of operations with grains (silkworm eggs), since a number of its physical and mechanical characteristics is insufficiently studied. It is important that processing mechanism would preserve the grain healthy and viable and would work with the optimum regimes. The purpose of the study was to determine some physical and mechanical characteristics of grains and to connect them with the optimum parameters of processing mechanisms. The development of the means of mechanization requires the investigation of the most important characteristics of grain – the flowability, which is the ability to form the stream under certain conditions, flowing under the action of gravitational force. It is expedient for the materials with the approximately identical granulometric composition, in particular for grains, to evaluate the degree of flowability by the numerical dimensionless quantity, deduced from the value of the angle of friction or bulk density. The cone with the angle of friction beta at the base is formed with the free efflux of bulk material from the capacity to the horizontal plane. We designated the index of flowability as Cf and studied the angles of the triangle of the cone. We determined the formula of flowability index:
Cf = 90/beta-1.
The investigations of the angle beta, Cf and bulk density gamma of grains revealed, that there is an empirical connection between these values:
γ =70.5√β + 311.2 kg/m3 ;
γ = 0.07√β + 0.3 g/cm3 ;
γ = 0.07√(90/Кс + 1) + 0.3 g/cm3.
These values were found for grains of commercial breeds and hybrids, used in the CIS ((B-1 x S-8) x (B-2 x S-9), B-1, B-1 x B-2, S-22, (S-8 x B-1) x 9(S-9 x B-2), B-2 x B-1). The bulk density of the studied breeds was within 632.0-705.0 kg/m3, the angle of friction – 23-31 degrees, flowability index – 1.95-2.75, the weight of one egg (grain) – 0.46-0.70 mg, specific weight – 10595 n/m3 (1.08 g.cm3), the coefficients of static friction of grains for different construction materials – 0.36-0.90. We used knowledge about bulk density values for determination of the dimensions of bunkers, feeders, and other machines .
Keywords: quality, processing, silkworm eggs, solution, operation, bulk density, angle of friction, frictional coefficient, flowability, microclimate.
Author Details: V.S. Burlakov, D. Sc. (Agr.), prof. (e-mail: Burlakov1309@ mail.ru); Y.N. Litvinov, Cand. Sc. (Biol.), assoc. prof.
For citation: Burlakov V.S., Litvinov Y.N. Investigation of Physical and Mechanical Properties of Silkworm Eggs. Dostizheniya nauki i tekhniki APK. 2016. V.30. No. 12. Pp. 98-100 (in Russ.).