Contents of Journal of Mechanical Engineering 60, 2 (2009)
HARIHARAN, V., SRINIVASAN, P. S. S.: Experimental investigations on bearing
housing vibration signatures caused by shaft rub 61
PAVLENKO, I.: Dynamic analysis of the locking automatic balancing device
of the multistage centrifugal pump 75
GUŽELA, Š., FEKETE, R.: Velocity of the particulate material outflow from
the storage 87
GUŽELA, Š., JURIGA, M., FEKETE, R.: The influence of particle size
of particulate material on the internal friction angle 105
Abstracts
Experimental investigations on bearing housing vibration signatures caused
by shaft rub
VAGGEERAM HARIHARAN, P. S. S. SRINIVASAN
Identifying vibration signature caused by rub on bearing housing is very critical in
preventing rub related machinery failure. Also, the effect of rub material and speed on vibration
signature associated with rub are two other key issues. In this paper, an effort has been made to
answer the above questions by simulating rub in a controlled way. The vibration signature on
bearing housing caused by shaft rub was studied by applying a rub on rotating machinery. Full
annular rub was simulated with two types of rub material, namely mild steel and aluminium.
Experiments were carried out at three speeds 740, 1150 and 1600 rpm. Time domain and
frequency domain signals on bearing housing with and without rub were collected and analysed.
Several observations on the effects of rub on bearing housing vibration are presented.
Dynamic analysis of the locking automatic balancing device of the
multistage centrifugal pump
IVAN PAVLENKO
The reliability of automatic balancing device of centrifugal pumps can be decreased in
case of intensive wear of cylindrical throttle before and after the unloading device of the
balancing disk. Therefore, the locking automatic balancing device is offered, operating as the
axial hydrostatic bearing with hyper bearing capacity and, simultaneously, as the non-contact
consolidation with self-adjustable leaking. The dynamic calculation is based on the equations
of pump rotor and regulator rod axial movement and also on equations of fluid flow balance
through throttles taking into consideration compression and displacement flow. The
methodology of dynamic calculation gives the opportunity to select the main parameters of
hydro-mechanical system engineering based on providing the transient processes quality and
stability conditions.
Velocity of the particulate material outflow from the storage
ŠTEFAN GUŽELA, ROMAN FEKETE
There is often a need to stock the particulate materials in industry. These materials can
be stocked by several manners: by means of the unit covers (paper bag, barrel, box...),
extensively (heap of bulk cargo) and intensively (bunker and silo). Various requests are made
by the demands on the storage design. One of them is the sluice size, which has to provide the
continuous particulate material outflow. If the conveyance for the particulate material transfer
from storage has to be correctly projected there is a need to know the outflow velocity of the
material from the sluice. The paper deals with the influence of the sluice size on the asked
velocity of the particulate material outflow from the storage.
The influence of particle size of particulate material on the internal friction angle
ŠTEFAN GUŽELA, MARTIN JURIGA, ROMAN FEKETE
Particulate materials are processed in various industrial equipments. It is necessary to
know the basic mechanical and physical properties of the particulate materials for the correct
design of such equipment. The angle of internal friction is one of the most important
properties of a material, and its identification is necessary for determination of the pressure
rate in the particulate material. Jenike's shearing apparatus determines the angle of internal
friction experimentally. The paper deals with the influence of the particle size on the angle of
internal friction. Its exact knowledge is necessary for the correct design and construction of
equipment for the processing of particulate materials.