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The current paper aims at optimizing the natural gas deliveries from an underground storage by implementing automated control systems and fiscal measurement systems according to the harmonized European legislation in the area of metrology. In the first part, the authors have carried out an analysis regarding the state of the art at international level with regard to technical solutions for optimizing the deliveries of natural gas by means of a constriction element of a measurement panel. In the following, a software application was created for monitoring the parameters taken from the process gas chromatograph and transferring them to the flow computer by implementing software filters. The novelty element here is that it allows the trading of the nominated natural gas amount in a set period of time.

Ergonomic design of the workplace is a matter of utmost importance. Ergonomics should consider reducing the high number of accidents as well as the high amounts paid for insurance. In recent years there have been numerous injuries due to cumulative trauma or due to psychological, sociological and ethical factors. Operators often adapt to improper work conditions, but the number of accidents increases and productivity decreases. The driver of the vehicle must be provided with a suitable space and position so that his posture is physiologically comfortable, does not cause excessive fatigue and illness, there is freedom of movement to drive the steering wheel, steering levers and pedals, which must be accessible and placed in such a way that the driver’s requirements are minimal and the visibility is ensured. In the paper there will be presented elements for the ergonomic design of the workplace for the motor vehicle occupation and will be taken into account several factors involved among which we mention the correct positioning of the seat adjustment while driving a car, adjusting the backrest and seat, adjusting the lumbar support, adjusting the steering position, adjusting the headrests to ensure that in the event of an accident, the risk of a head injury is very small.

Whereas formerly metallic materials were used extensively and for various purposes in the machines manufacturing industry, nowadays new materials are sought that can replace the "conventional" machines manufacturing materials with new ones. This is especially challenging in areas where parts need to be able to withstand very tough conditions, such as high temperatures or large forces applied to them. The current paper intends to analyze some of the most widely used materials for high-strength applications. A special focus in this regard is on the one hand in fiber-reinforced composite materials with the polymer matrix and on the other hand on basalt. The most important properties, processing technologies and applications of these materials are analyzed and discussed and conclusions are drawn regarding their compatibility with the intended purpose.

During the tests for evaluating shock behavior for certain alloy steels, one of the stages consists of an analysis of geometrical and structural degradations. These degradations are functions of stress distribution, values, and module of plastic and elastic deformation energies involved. High values of kinetic energy generated at shock imposed the necessity for a scientific model of study / simulation. The presented model allows a further extension for ranges of values and restrictions imposed to shock stresses for certain alloy steels special structures. In order to evaluate and calibrate the presented model, some experiments were conducted. Data resulted from experiments was compared to data resulted during simulations. After calibration and confirmation of proposed model, new parameters could be computed, parameters that were unavailable in experimental studies. The present paper presents some considerations regarding the adopted methodology, results, and perspective for further experimental trials and simulations.

Castability is, along with biocompatibility, one of the most important characteristics of metallic materials used for dental prosthetic applications. In addition, the characteristics and performance of the employed casting machine are also decisive for the end result of the casting, especially when dealing with titanium or a titanium alloy. Starting from a critical analysis of the existing methods for determining the castability of dental alloys, the current paper presents a new method (and associated pattern) for determining the castability. Also, given the castability’s dependence on the type of casting machine, the paper includes an analysis of suitable casting machines and suggests some possible improvements.

Starting from a new study on carbon monoxide and noise pollution levels in an important crossroads area of the city of Sibiu, Romania, the current paper uses the data to compare with data obtained during past studies carried out on the same area, allowing an assessment of the evolution of the two pollution indicators over time. The recent study, carried out over a two-week period in November 2017 both during the peak morning hours and at midday, combined a video-based vehicle count with measurements of the carbon monoxide and of the noise level, respectively. The data comparison reveals not only a worsening of the pollution levels in the centre of Sibiu over the past few years and should allow the determining of the best methods and means for reducing the level of the pollutants, possibly in correlation with the improvement of the road traffic conditions.

Establishing which metallic materials are suitable to be used for the protection of operators and machinery, when subjected to stress impact in the drilling industry, for surface exploitation, mines and quarries, is a complex process. Due to the harsh operating conditions, a careful evaluation of the various materials used is of utmost importance. This paper addresses the issues relating to the methodology of determining the appropriate homogenous materials to be used, based on a correspondence between their characteristics and applications. Starting with a list of specific operating conditions, one has established a set of requirements and has assessed the market; the recommended materials for the job are alloy steels and aluminum alloys.

The paper analyzes the possibility to use a neuro-fuzzy type mathematical model, with the final goal of establishing the welding parameters for new types and dimensions of pipes and fittings. Anticipating the developing dynamic of polyethylene-made elements, especially pipes and fittings, starting from the current situation when already a wide range of pipes and fittings with different wall thicknesses and nominal working pressures is produced and commercialized, and taking into account also new development, it was considered necessary to find out the welding parameters for any new pipe type and dimension. The usage of existing welding equipment for new pipe dimensions is impossible without a preliminary set of welding parameters: pressure, temperature, time. Based on experimentally validated data for discreet values of the characteristic welding parameters, there was generated, using mathematical laws and functions, a new model that can estimate the necessary values of the welding parameters for any value within their variation range. As a result, the mathematical model created using neuro-fuzzy techniques allows the obtaining of the correct value for certain parameters (e.g. required welding pressure) for any values of the input variables pipe diameter and pipe thickness.

Noise pollution is one of the most important negative effects of road traffic, especially in cities. The current paper presents an attempt to reduce the noise level created by the road traffic along some main roads in the city of Sibiu, Romania by suggesting ways to optimize the traffic flow. The number of cars and the resulting noise levels were recorded in a key area of Sibiu. The noise levels were compared to standards and to measurements taken in areas with less traffic. Then, they were fed, together with road geometry data, into a specialized simulation software that allowed the computer-aided reproduction of the traffic flow, but also the modifying of conditions such as the road geometry to achieve, coupled with a multicriterial analysis, an optimization of the pedestrian and road traffic flow in view of a reduced noise pollution.

The current paper presents a computer-aided analysis of the way in which a natural gas storage created in a depleted gas deposit and the associated gas collection network are operated, both during the extraction phase and during the injection phase. In a first step, an analysis is carried out on a two-dimensional, nonstationary model for the gas storage, based on the deposit’s geometry and the rock properties, but also on the gas motions. Also, a dynamic simulation of the injection and extraction processes is unfolded, allowing the study and optimisation of elements such as well placement and gas flows through the wells with the goal of maximising the storable gas quantities. A second model is then generated for the gas collection network associated with the natural gas storage, using the simulation software Simone. Its main benefit is allowing the simulation and modelling of nonstationary flows through the network. The two models are closely interconnected, in that for the extraction stage, the output from the first model is used as input for modelling the collection network, while for the injection phase, the results from modelling the collection network are used as entry data for the gas storage model.

The quality of the natural gas extracted from deposits and transported through pipelines is a major factor in achieving the desired heating properties of the gas. A big problem related to the quality is the presence of impurities such as dust, sand or water. These can be removed by using separators. This paper presents an analysis of the efficiency of a cyclone-type separator in terms of speeds and pressure drops, using the computational fluid dynamics (CFD) method in the case of separating water droplets from the main gas flow.

Whereas formerly metallic materials were used extensively and for various purposes in the machines manufacturing industry, nowadays new materials are sought that can replace the "conventional" machines manufacturing materials with new ones. This is especially challenging in areas where parts need to be able to withstand very tough conditions, such as high temperatures or large forces applied to them. The current paper intends to analyze some of the most widely used materials for high-strength applications. A special focus in this regard is on the one hand in fiber-reinforced composite materials with the polymer matrix and on the other hand on basalt. The most important properties, processing technologies and applications of these materials are analyzed and discussed and conclusions are drawn regarding their compatibility with the intended purpose. [ABSTRACT FROM AUTHOR]

During the tests for evaluating shock behavior for certain alloy steels, one of the stages consists of an analysis of geometrical and structural degradations. These degradations are functions of stress distribution, values and module of plastic and elastic deformation energies involved. High values of kinetic energy generated at shock imposed the necessity for a scientific model of study / simulation. The presented model allows a further extension for ranges of values and restrictions imposed to shock stresses for certain alloy steels special structures. In order to evaluate and calibrate the presented model, some experiments were conducted. Data resulted from experiments was compared to data resulted during simulations. After calibration and confirmation of proposed model, new parameters could be computed, parameters that were unavailable in experimental studies. The present paper presents some considerations regarding the adopted methodology, results and perspective for further experimental trials and simulations. [ABSTRACT FROM AUTHOR]

Many parts used in the machines manufacturing industry need to present a high hardness value on certain areas and thus need to be subjected to heat treatments or thermochemical treatments such as plasma nitriding, while other areas can be left in their initial hardness state. Since applying plasma nitriding on all surfaces would be needlessly costly, it is necessary to apply a solution for the local protection of the areas that do not require hardening. The authors of the current paper, starting from their previous researches on elaborating special paints or pastes for the local protection of parts against the effects of plasma nitriding, are analysing in this paper the various types of materials that can be used as binding agents in the composition of such paints or pastes, from the point of view of their protection efficiency and their mechanical properties. [ABSTRACT FROM AUTHOR]

Due to the many technical-economical advantages it offers in comparison to the classical heat treatment processes, plasma nitriding has in recent years considerably enlarged its range of industrial applications. The main purpose of plasma nitriding is to provide advantageous conditions of the parts' machinability and reliability, by modifying their chemical composition, the structure and reducing any internal stresses. Nitrogen diffusion in the base material's crystal lattice creates in the parts' superficial layer compounds that determine an increase in wear and corrosion strength and an improvement of the general tribological properties. In the current paper, the authors focus on the kinetics of forming and on the hardness of layers obtained after plasma nitriding in structural steels such as 39CrAlMo6-9-2, 42CrMo4, 18CrMn4-4 and 40Cr4. [ABSTRACT FROM AUTHOR]

In the current paper the authors present some experimental researches regarding the depollution through combustion of soil samples that were contaminated with hydrocarbons. Determinations were carried out on chernozem-type soils with high germinative potential, artificially polluted with an oil-derived fraction with known characteristics and a clay-type soil accidentally polluted with an oil-derived fraction of unknown composition. Several combustion tests were carried out, varying the combustion and calcination time. The tests have shown that the calcination time should be of at least 10 minutes to eliminate the pollutant, but the actual duration does not significantly influence the result. [ABSTRACT FROM AUTHOR]

The paper presents a part of the comparative experimental researches carried out by the authors on ring-type parts made of a powder mixture consisting of austenitic stainless steel AISI 316L and alumina (Al2O3) powder and on valve supports from the engines of Volkswagen and Audi cars. The purpose of the researches was to determine whether the mentioned valve supports could be manufactured also of the analysed powder mixture. The analysed powder mixture resulted from previous researches carried out by the authors and from studies in the speciality literature. The experiments first targeted the microstructures and microhardnesses of samples taken from the supports of admission and evacuation valves from Volkswagen (A1 and E1) and Audi (A2 and E2) cars, respectively. The same analyses were then applied to ring-shaped parts made by sintering from a mixture of austenitic stainless steel 316L + 30% alumina (Al2O3) powder. [ABSTRACT FROM AUTHOR]

This paper presents the realization of a model for the collecting and adduction network for a natural gas storage, capable of being coupled by boundary conditions to the collector and to the transportation network. The model for the gas collecting network is performed using Simone simulator and has the power of shaping a non-stationary flow through the transportation network. This is necessary because the gas flow rates for each day , vary based on customers' needs. The collecting network model reflects the reality from the ground level and it is built based on GIS data concerning the dimensions of the pipe. [ABSTRACT FROM AUTHOR]