¹ 4(29), 2007

S U M M A R I E S

 

DYNAMIC ANALYSIS OF DRIVING HINGED MECHANISMS OF COMPOUND NEEDLES OF THE LOOP-FORMING ELEMENTS OF WARP-KNITTING MACHINES. N. Davitashvili, L. Demetradze, L. Gergeshelidze. “Problems of Mechanics”. Tbilisi, 2007, ¹ 4(29), pp.  7-16, (Engl.).

The dynamic investigation for plane six-link driving hinged-lever mechanisms of  compound needles of the loop-forming elements of warp-knitting machines is given.  On the first stage of investigation for a certain type mechanism of a compound needle  it is determined theoretical kinematic parameters (position, velocities and accelerations) for all output links and their points. On the second stage of investigation it is conducted a dynamic analysis of the mentioned mechanism, when all links are absolutely rigid. The differential equation, determining the real law of motion of input link, all  output links and their points, is obtained. 3 ill. Bibl. 7. Engl.; summ. in Russ.

 

EFFECT OF TRACTIVE EFFORT ON INSTANT MOVING RAILWAY VEHICLES.
M. Chelidze, G. Tumanishvili, I. Tumanishvili. “Problems of Mechanics”. Tbilisi, 2007,
¹ 4(29), pp. 17-23, (Engl.).

Inconstancy of tractive effort of the locomotive causes inconstancy of effort, working on each car. Lateral, longitudinal and rotary fluctuations of cars are considered. The rolling stock is considered as articulated-link connected flexible chain with articulated joint lumped masses. In such conditions arise lateral oscillations caused by displacement of the centers of gravity of separate cars from a longitudinal axis of symmetry of track (similarly of physical pendulum oscillating in a gravitational field). Unsteady motion of the car was examined in consideration of nonlinearity of lateral rigidity of track. 11 ill. Bibl. 8. Engl.; summ. in Russ.

 

Interrelation between technology of sewing-products-assembly and desing for their realization. T. Uriadmkopeli, D. Purtskh­vanidze, M. Gurgenidze. “Problems of Mechanics”. Tbilisi, 2007, ¹ 4(29), pp.  24-27, (Engl.).

The questions on interrelation between the technology of automated assembling of sewn products and the technical solutions for their realization are considered. It is proved that the connection indicated, in essence, consists in the progressiveness of a new technology, which is determined by its correspondence to main ultimate purpose – qualitative fulfillment of the technological processes of assembling sewn products and to an increase in competitive capacity of output products. The criteria of the progressiveness of a new technology are formulated and on the basis of an engineering study there are proposed the method and the formula for determination of the progressiveness of a new technology by taking into account the periods of service. 3 ill. Bibl. 6. Engl.; summ. in Russ.

 

KINETICS OF STRUCTURAL AND PHASE TRANSFORMATIONS OF BRAKE MATERIALS SUPERFICIAL LAYERS ON FRICTION  NATURE. N. Meliksetyan. “Problems of Mechanics”. Tbilisi, 2007, ¹ 4(29), pp. 28-32, (Russ.).

Structural and phase transformations of friction brake materials superficial layers have been considering under high temperature friction nature. It has been revealed by X-ray structural analyze method that texturing, amorphisation and recrystalization of layers are taking place depending on superficial temperature up to layers destruction. 3 ill. Bibl. 8. Russ.

 

TEMPERATURE FIELDS OF THE LINE ELECTRIC SOURCES OF HEAT AND
 SQUARE HEATING SPIRALS. A. Tvalchrelidze,  D. Kakabadze, K. Tskhakaia. “Problems of Mechanics”. Tbilisi, 2007, ¹ 4(29), pp. 33-39, (Russ.).

On the ground of finite element temperature target setting in the theory of shells with use of several datum surfaces the mathematical model for investigation of the temperature fields of ceramic heaters with line heat sources has been elaborated. The feature of the model is taking into account of dependence of the source on the temperature field (connected problem of the temperature fields of line source and heater). Mathematical modeling of the radiated temperature fields has been conducted for constructive and operating conditions of the experimental heating ceramic element with electric spiral. The comparison of theoretical results and experimental measurements showed their good compliance. 4 ill. Bibl. 3. Russ.

 

The analysis of face mills reliability and evaluation of failure probability. M. Iremadze, L. Zivzivadze. “Problems of Mechanics”. Tbilisi, 2007, ¹ 4(29), pp. 40-45, (Russ.).

Obtained statistical failure probability models, probability density and failure intensivity show, that exploitation reliability of face mills depends on their working time, face mill diameter and on spurs number. These models enable us to define the level of face mill exploitation reliability. 1 ill. Bibl. 10. Russ.

 

To determination of the dimensions of haRd-alloy cutting plate for cutting with high-temperature preheating. G. Khvichia, M. Silogava. “Problems of Mechanics”. Tbilisi, 2007, ¹ 4(29), pp. 46-51, (Russ.).

In this work, the theoretical expressions for calculations of overall dimensions of hard-metal plate of lathe tools for grinding of steels and alloys with preliminary high-temperature heating of shorn layer are given. Their application with a sufficient precision during construction of a turning rougher is experimentally confirmed. Recommendations regarding the selection of form and dimensions of a hard-alloy cutting plate are given. 4 ill. Bibl. 4. Russ.

 

The analysis of results of experimental studies of automobiles working on mixed fuel. O. Gelashvili, I. Chkhetia, V. Dzhadzhanidze. “Problems of Mechanics”. Tbilisi, 2007, ¹ 4(29), pp. 52-56, (Russ.).

The expediency of applying a gas fuel for diesel automobiles is substantiated. The promising ways of transfer of diesels to gas-diesel process are shown and the results of the experimental tests of gas balloon automobiles given. Bibl. 4. Russ.

 

FINITE ELEMENT TEMPERATURE TARGET SETTING IN THE THEORY OF
 PLATES WITH USE OF SOME BASIC SURFACES. A. Tvalchrelidze,  D. Kakabadze, K. Tskhakaia. “Problems of Mechanics”. Tbilisi, 2007, ¹ 4(29), pp. 57-61, (Russ.).

In the article there is given a numerical algorithm for investigation of temperature fields of the plates taking into account the gradient of temperature field by thickness on the basis of variational temperature problem of the theory of shells with use of some basic surfaces and Finite Element  Method. There are given the results of computing experiment of researching of the non-stationary temperature field of the ceramic plate heated by internal linear source. 3 ill. Bibl. 5. Russ.

 

PARTICULARITIES OF DESIGNING OF HELMSMEN MANAGEMENT OF CAR. Zakir Ali Aga ogli Rustamov. “Problems of Mechanics”. Tbilisi, 2007, ¹ 4(29), pp. 62-67, (Russ.).

Helmsmen management is faced with a number of high requirements, one of which, greatly influencing upon sustainability and maneuverability of the car, is a minimum lateral slide of wheel at tumbling. According to some sources, for provision of good controllability and increase of sustainability, “operated wheel under its tumbling must roll without lateral slide" or "helmsmen drive must provide the correct correlation angles of tumbling of operated wheels". Specifically to make the tumbling of the car without lateral slide, operated wheel must turn round on different angles. Following the availability of the correlation between angles operated of wheels the impact of the present correlations on maneuverability and sustainability of the car was analyzed. It is offered new constructive solution of helmsmen management and independent suspension, for improvement of maneuverability and increasing stability of the motor transport. Moreover, the analysis of joint work of the elements of  mechanism was conducted while revealling the essence of the new design and relevant method of calculation for determination of parameters was suggested. 5 ill. Bibl. 5. Russ.

 

GEOMECHANICAL SUBSTANTIATION OF THE SYSTEM PARAMETERS AT DESCENDING HORIZONTAL LAYERS WITH THE HARD BACKFILL. A.H. Hovhanesyan. “Problems of Mechanics”. Tbilisi, 2007, ¹ 4(29), pp. 68-75, (Russ.).

The definition of backfill mass bearing ability at descending system of underground mining with level-by-level ore development is considered in this article. Geomechanical researches reveal the appropriateness of variability for the required backfill mass strength from the development stages of operational layer and dependence of maximum permissible width of an artificial roof exposure on thickness of a bearing. . 4 ill. Bibl. 7. Russ.

 

INVESTIGATION OF THREE-LAYERED CONSTRUCTIONS FOR ECOLOGICAL PROTECTION OF AERIAL ENVIRONMENT. G. Kipiani, M. Lursmanashvili. “Problems of Mechanics”. Tbilisi, 2007, ¹ 4(29), pp. 76-79, (Russ.).

In the work the procedure of calculation of three-layered constructions used both in building and protection of nature is presented. The thermal insulation properties of panels are investigated and the reliable results obtained, which determine the strength and the reliability of three-layered constructions. Bibl. 4. Russ.

 

OPTICAL CONTROL OF TECHNOLOGICAL PROCESSES IN MANUFACTURE OF SILICOMANGANESE. Ts. Geguchadze, A. Getsadze, M. Shalamberidze, A. Goglichidze. “Problems of Mechanics”. Tbilisi, 2007, ¹ 4(29), pp. 80-84, (Engl.).

In a given work there is considered the activity of harmful impurities in manganese alloy and on the base of it there is also considered the improvement of refining process and the increase of liquid metal's productivity with the decrease of the receiving metal's cost by means of the improvement of the refining process' controlling method. 2 ill. Bibl. 3. Engl., summ. in Russ.

 

INCREASING TRANSIT DIRECTIONS OF GEORGIAN RAILWAY TO ITS FULL CAPACITY. P. Kenkadze, Dj. Morchiladze, T. Kotrikadze. “Problems of Mechanics”. Tbilisi, 2007, ¹ 4(29), pp. 85-88, (Russ.).

The article refers to the ways of improvement of functioning of transit directions of Georgian Railway during reconstructive process in order to increase their capacity. 1 ill. Bibl. 3. Russ.