• ## OPTIMIZATION RESEARCH OF THE CARGO PENDULUM AND UNITS DISPLACEMENTS OF THE GANTRY CRANES LEVEL LUFFING JIB SYSTEM

Machines. Technologies. Materials., Vol. 12 (2018), Issue 10, pg(s) 386-391

A new methodology for taking into account of the cargo pendulum angle change at minimum operating radius of the gantry cranes level luffing jib systems is proposed. The impact of this change in electric motor power calculating has been studied. An optimization mathematical model that takes into account this change and the impact of node displacements on the design of the gantry cranes level luffing jib systems is built. Parameters, optimization criteria and their boundaries are determined. Optimization of the construction taking into account these factors was made using the Pareto optimization procedure and the results were compared with previous studies.

## NEW STRUCTURE OF THE GANTRY CRANES LEVEL LUFFING JIB SYSTEM

A new construction of the gantry cranes level luffing jib system has been proposed. Its important operating characteristics has been studied. An optimization mathematical model of these structure is built. The parameters, optimization criteria and their limitations are defined. The optimization of construction is done using the Pareto optimization procedure in MATLAB. All parts and assembled units of the gantry cranes level luffing jib system have undergone optimization in practice. The results of the optimization study of the new design are compared with those of the traditional structure.

• ## DETERMINING VOLUMETRIC DISPLACEMENT OF EXTERNAL GEAR PUMPS

в настоящата работа са представени редица методи за пресмятане на работния обем и теоретичния дебит на зъбни помпи с външно еволвентно зацепване. Разгледани са зависимостите, предложени от различни автори за определяне на тези показатели, като е извършено сравнително изследване на точността при определяне на работния обем за конкретна зъбна хидравлична машина, за която опитно са дешифрирани геометричните параметри. Резултатите показват значително отклонение от дадената заводска стойност на работния обем, като в някои случаи това отклонение надвишава 25%.