ISSN 2343–7707 ; ISSN-L 1453-7303


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Heavy Duty Machine Tools – Hydraulic Balancing of the Kinematic Chains

The authors of this paper introduce some of the hydraulic balancing systems for the large rams, cross-rails and housings which travel vertically. These systems are used for the feed and/or positioning kinematic chains of the heavy-duty machine tools. The paper presents the hydraulic basic diagrams, the methodology of calculation and the manufactured units. These low-cost systems are equipped with usual hydraulic devices. The balancing hydraulic units can be used for … (read more)

Automatic Processing Station Actuated by Pneumatic Drive
Author: Ionel Laurentiu ALBOTEANU

The paper presents an automatic processing system made on a small scale. The entire structure is integrated in an electro-pneumatic drive system with linear actuators and rotary pneumatic motors, supplied by the solenoid valves. The system is controlled by a PLC in accordance with … (read more)

Testing of Operating Characteristics with Powershift Multi-disc Clutches
Author: Attila SZEGEDI

The diverse requirements pose complex demands on today’s agricultural tractors. Effective work requires a modern diesel engine to have an efficient and versatile drivetrain, since the engine’s performance must be transmitted to the ground and the wheel with minimal loss. At the same time, the activated gear ratio ensures optimum engine load in the otherwise wide range of speeds to reach low fuel consumption. For this reason, powershift transmissions are most often used under modern loads. The critical point of their operation is … (read more)

Reducing Pollutant Emissions by Integrating Flue Gas Treatment Systems into a Corn Coal Fired Coating Plant
Authors: Adrian ȚENCHEA, Dănuț TOKAR, Adriana TOKAR

The European Union’s 2020 greenhouse gas reduction targets bring solid biomass to the attention of specialists as one of the renewable energies on which Europe can rely. The technical potential for biomass use is about 8-10% of the primary energies in Europe. The amount of heat from the energy recovery of biomass, in Romania, has different weights in the balance of primary resources, depending on the type of waste used or the destination. The rational use of biomass involves knowledge of … (read more)

Using Complex Liquid-Measuring Devices in Fire Hoses
Authors: Nikolett FECSER, Filomena HAROMI, Rajmund KUTI

Up to now, it is still very common to use water for extinguishing fire. To be able to ensure the adequate water supply, it is essential to examine the parameters of the water supply system, especially in the case of firefighting devices, which are sometimes used under extreme conditions. To ensure the proper amount of firewater and to carry out the necessary modifications, it is vital to examine the firewater supply system from the pump including the pipes to the nozzle. We aim at making such a complex measuring instrument that provides … (read more)

The Correlation between the Composition of the Gas Mixture Injected into Water and the Concentration of Dissolved Oxygen in Water
Authors: Nicoleta Dorina ALBU, Elena Beatrice TĂNASE, Nicolae Vlad SIMA, Nicolae BĂRAN, Corina MOGA

The paper presents three versions of gas mixtures: atmospheric air, atmospheric air and oxygen from a cylinder, air with low nitrogen content supplied by oxygen concentrators. These mixtures are successively introduced into a water tank and the theoretical and experimental determination of  (read more)

2D Numerical Model of a River Sector Flow in Case of Hypothetical Side Flooding Due to Embankment Failure
Authors: Albert Titus CONSTANTIN, Gheorghe I. LAZĂR, Şerban-Vlad NICOARĂ

The paper presents a 2D numerical modelling of water flow on a sector of about 7800m of Timiş River downstream of Lugoj Town, west of Romania, in case of accidental highwaters produceing side flooding due to a hypothetical embankement breach. The numerical simulation, assimilating the special high-flow values that occurred on site along (read more)

Theoretical Characteristics of Fluid Flow within a Pneumatic System
Author: Fănel Dorel ȘCHEAUA

There are numerous applications in industry branches that use pneumatic drive to achieve various imposed movements for the working body. Here the working fluid is represented by a gaseous medium that is influenced by the temperature, humidity and pressure values. With regard to the flow pattern, a clear distinction must be made between the fluid volume at inlet and the discharge volume due to air compressibility properties. Specific parameters regarding the state of the working fluid are given by volume, pressure and temperature and any momentary modification of these specific values depends on … (read more)

New Actuator Type Using Magnetically Controlled Rheological Properties of Fluids
Authors: Dan SCURTU, Doru CĂLĂRAȘU

The paper presents the concept of new type of actuator that uses the specific properties of a magneto rheological fluid. The proposed actuator allows controlling the speed of a mechanical element and its positioning. The paper gives details about  … (read more)

Simulation of the Cargo Tank Cleaning Plant for an Oil Tanker
Authors: Mariana PANAITESCU, Fănel-Viorel PANAITESCU

In order to achieve the modeling of the sea water system through the freight tanks installation, the Ansys-Fluent v.14.5 programme was used. The help of the Design Modeler option offered by Ansys Fluent program has been performed by the geometry of a sealer from … (read more)

Influence and Effects of Pressure Variation on the Life Span of External Gear Pumps
Authors: Polifron – Alexandru CHIRIȚĂ, Teodor-Costinel POPESCU,
Alexandru – Daniel MARINESCU, Constantin TEODORU
Corneliu CREȚU

The article analyzes the effects of variable pressure on the life of hydraulic gear pumps using modern numerical simulation tools (CAE & CAD). It presents the results of a static and a dynamic analysis (fatigue) as well as experimentation, validating these simulations, with the ultimate goal of … (read more)

Computer Analysis of Water Flow Transition under Existing Conditions on a River Sector in the Range of a Bridge Structure
Authors: Şerban-Vlad NICOARĂ, Gheorghe I. LAZĂR, Albert Titus CONSTANTIN

The paper presents a 2D numerical modelling of water flow transition on a sector of Strei River in the range of the DN7 national driveway bridge at km.376+818, outside the built-up area of Deva Town (upstream of Simeria), Romania, in case of a special highwaters phenomenon. The considered synthetical hydrograph follows an exceptional hydrologic event that occurred in … (read more)

Researches on the Operation of a Fine Bubble Generator and Oxygen Concentrators
Authors: Rareș Dumitru PĂUN, Nicolae BĂRAN

Two water treatment procedures are presented in the paper:
– a process for aerating the water with the help of a fine bubble generator;
– a process for waters oxygenation by means of oxygen concentrators.
In both processes, … (read more)

A Review & Progress on Digital Hydraulic Pumps and Valves
Authors: Darshan KATGERI, Basavaraj HUBBALLI

The main challenge in design of hydraulic circuits is to obtain desired flow rate and maintain required pressure, this is accomplished by using various types of hydraulic valves and other hydraulic elements. In this review paper work carried out by authors on valves with special emphasis on … (read more)

From Human-Environment Interaction to Environmental Informatics (III): the Social-Ecological Systems dynamics in Knowledge-based Society
Authors: Mirela COMAN, Bogdan CIORUȚA

Since its inception, human society has noticed that there is a close relationship between the activities it carries out and the way in which the environment behaves; however, attempts to adjust activities to health and environmental integrity have been delayed even in this Knowledge-based Society. Nowadays, the environment, as a third part of sustainable development modern concept, plays a crucial role in … (read more)

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