Mathematical Modeling, Laboratory Testing and Numerical Simulation of a Servo-Pump as Part of a Closed Circuit Primary Control Hydrostatic Transmission for Multi-Purpose Trucks
Authors: Alexandru-Polifron CHIRIȚĂ, Cristian PAVEL
The current paper presents the dynamic mathematical models of the components of a hydrostatic transmission, the results of physical tests performed in the laboratory on a servo-pump that is part of a closed circuit primary control hydrostatic transmission, and its numerical simulation results. The acquisition of the experimental data as well as the control of the experimental stand have been carried out with the LabVIEW application, while the numerical simulation … (read more)
About Computer Tools Available for Dynamic Analysis of Mechanic and Hydraulic Systems of the Loader Bucket
Author: Carmen Nicoleta DEBELEAC
The paper focuses on modelling and simulation a feedlot bucket (0.7 m3 capacity) from skid steer loader, with hydraulic acting, using specialized engineering computer-based environments. It was highlighted the capabilities of these design tools by exemplifying some case analyzes (drawing 2D and 3D shape of component elements, testing the … (read more)
Effective Solutions to Reduce Energy Consumption in the Turbo-Blowers of a Sewage Treatment Plant
Authors: Mariana PANAITESCU, Fănel-Viorel PANAITESCU, Alexandru-Andrei SCUPI
Since the energy consumption of the turbo blowers represents 68% of the energy consumption of the station, it was sought to reduce this consumption by installing oxygen sensors in the bioreactors; these sensors detect the reaching of the optimal (maximum) oxygen threshold of 2.0% and at this moment they partially close the butterfly valves from the discharge of the turbo blowers, which leads to the reduction of the flow rate and implicitly the energy consumption of the turbo blowers. Through the SEAU’s SCADA system for the oxygen volume, the necessary data were obtained to calculate the percentage opening of the butterfly valves from the discharge of the turbo blowers in order to … (read more)
Modification of Cavitation Erosion Resistance of Aluminum Alloy 7075 by Maintaining of Artificial Aging Heat Treatment at 180°C
Authors: Ilare BORDEAȘU, Alexandru Nicolae LUCA, Iosif LAZĂR, Dragoș LAZĂR, Rodica BĂDĂRĂU, Brândușa GHIBAN, Andreea Daniela BUZATU, Alin Mihai DEMIAN, Ovidiu Petrișor ODAGIU, Lavinia Mădălina MICU
The use of volume heat treatments aims to change the microstructure and the values of the mechanical properties, with homogeneous distribution in the volume of the part, so as to confer resistance to various stresses. From the point of view of the hydrodynamic stresses of the microjets generated by the cavitation mechanism, these treatments ensure an increase in the life of the required surface. In the case of aluminum-based alloys, volume thermal treatments do not produce important changes in the structural phase, but they cause important changes in the values of the mechanical properties. As these alloys have small specific masses and good mechanical properties, research is currently being resumed aimed at … (read more)
A State-of-the-art Review of Compaction Control Tests Methods
Authors: Andrei BURAGA, Carmen Nicoleta DEBELEAC
Quality control methods have been used by construction civile industry and road for many years to control the compaction process carried out, either of the soil or of the asphalt mixtures. These control procedures are based upon experimental and/or statistical concepts and their goal are to be an instrument to assist the contractor to carry out the execution checks in insuring that impose degree compaction was achieved in accordance with technical project of the works. These concepts are built around the idea according to which it is possible to … (read more)
Aspects regarding the Use of Hydraulic Motors
Authors: Alexandru BOBE, Tiberiu AXINTE, Cătălin NUȚU, Cătălin FRĂȚILĂ, Mihai DIACONU
This article represents research regarding use of hydraulic motors. The role of hydraulic motors is to convert fluid pressure into rotary motion. The motor considered in this article is a hydraulic actuator. The hydraulic motor works only with a pump unit. A pump unit usually has a maxim pressure of 6·105 Pa. Hydraulic motors can be used for various applications, such as: excavators, shredders, drilling rigs, winches, crane drives, cooling fan drivers, feeder, roll mills, launch and recovery systems (LARS), etc. After introduction, the authors study … (read more)
System for Velocity Adjustment and Control of a Closed-Circuit Secondary Adjustment Hydrostatic Transmission
Authors: Alexandru-Polifron CHIRIȚĂ, Radu Iulian RĂDOI, Bogdan Marian ȘERBAN, Ana-Maria POPESCU, Andrei-Alexandru BENESCU
This article focuses on the design and testing of a close-circuit secondary adjustment hydrostatic transmission. The interface between the acquisition board and the computer is done by LabView programming environment. The process is regulated by a PID controller. The system uses the controller output value to push the process variable toward the setpoint value. Control schematics include … (read more)
Reliability Analysis and Automation of the Equipment for Pressing Axial Bearings in the Gearboxes
Authors: Roxana-Luiza IFRIM, Ioan-Lucian MARCU, Daniel-Vasile BANYAI
This paper aims to highlight the development of industrial modernization of a simple process: the pressing of axial bearings in the gearboxes, which is a crucial step in the assembly process, as it ensures that the bearings are securely fitted and able to withstand the forces that will be applied to them. In the past, this task was performed manually, which was time-consuming and prone to … (read more)
Some Pressure Drops Characteristics for Pressure Valves Operation within the Hydraulic Circuit
Author: Fănel Dorel ȘCHEAUA
At present time, most machines and equipment in the industry use hydraulic actuation to ensure the fulfilment of the required work process. It represents a force system that successfully copes with the demands that the actuation of any working organ implies, but which must be well dimensioned and protected against overloads by means of protective equipment. The pressure valves represent protection elements of the hydraulic circuit against pressure peaks formed on the network as a result of … (read more)
An Overview of the Linear Drive with Solenoid Coupling
Authors: Viorel PANAITESCU, Tiberiu AXINTE, Victor BĂDĂNĂU, Camelia PASCU
The paper presents an overview of the economic efficiency for linear drive with solenoid coupling. Moreover, the linear drive with solenoid coupling is also a pneumatic device. Thereby in this article, we are studying two pneumatic and one electro-pneumatic installation, which contains the linear drive with solenoid coupling. The first pneumatic circuit contains … (read more)
