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The paper shows the dynamics of accidents and industrial fatality injuries at the Main Pipeline Transport of Hydrocarbons in the Russian Federation. The features of operation of a Gas Distribution Station (GDS) as one of the Hazardous Production Facilities of Main Pipeline Transport of Natural Gas are considered. The main technological units and systems for ensuring the complex safety of automated low-performance GDS are presented. The main factors contributing to the occurrence and development of accidents at the GDS are listed. To increase gas supplies to the consumer, the calculation of the technically possible throughput capacity of the existing GDS with a design capacity of 20 thousand m3/hour was carried out. Using a software complex “Vesta-GDS” we built process flow diagram that under the given constraints (pressure, temperature, gas velocity in the pipeline and the degree of opening of the gas pressure regulator valve) determined that the technically possible throughput capacity of GDS is 16.37 thousand m3/hour more than design capacity. With technically possible increased productivity, a qualitative and quantitative assessment of the risk of an accident at the GDS II class of danger was made, as a result of which the risk was assessed as “low” and not exceeding the background indicators of the oil and gas industry of the Russian Federation.

When designing a variable capacity pressure regulator, it is necessary to select parameters that meet certain criteria. In this article optimization of regulator parameters by LPτ search method is considered. The mathematical model of the regulator is made, a possible set of quality criteria is given, dependent criteria are established and the majority of approximate effective points are found. Setting of criteria restrictions is performed in the dialog mode. The methods described in the article allow to obtain an optimal design of the pressure regulator with variable characteristic.

Nowadays, with increased environmental requirements to improve fuel economy, it is important to work with both the ICE and the other elements of propulsion. This report describes how to operate automatic gearboxes and specially General Motors 6T. They are very widespread throughout the world and are used by many automotive manufacturers. The deficiencies encountered during the operation and the reasons for this are discussed. There was considered the opportunities for diagnosis, emerging operational problems and the options for their removal. It is suggested to replace parts exchange details of the construction in order to improve performance and reliability. The solenoids that control the switching are ON / OFF type or pressure regulators (with a progressive or regressive characteristic). A stand test of solenoids - pressure regulators has been done under cold and warm conditions. The test results are shown in tabular and graphical form. Using this method reduces the repair time of an automatic gearbox.

The paper deals with the theoretical and experimental analysis of a proportional pneumatic device. Such a piece of equipment can be integrated in the structure of an intelligent system that works with compressed gases. Different constructive variants of this type of equipment are analyzed. Authors focus their attention on a device that makes use of an electro-mechanic actuator operating with a proportional electromagnet. For the mathematical model some simplifying assumptions are identified. The mathematical model is numerically integrated. The behavior of the proportional pneumatic device at the variation of the inlet pressure and outlet mass flow rate consumption is pointed out.

One of major pressure regulator features is its static characteristic. It is necessary to choose parameters fulfilling static characteristic requirements while designing a regulator. The article observes possible requirements imposed on static characteristic and shows mathematical description of balance of pressure regulator with variable characteristic. Static characteristics are plotted for some of parameters being varied and others fixed. Influence of parameters is analyzed on the base of obtained data and recommendations for its choosing are given.

Most of LPG explosions are caused by undetected gas leakage in the pre-detection condition. So that, LPG detection system is needed. The purpose of this system is to detect gas leakage, neutralize it, and prevent the explosion. Gas leakage could happen due to improper regulator installation or the hose is broken. This detection should not work in just one location because gas can leak at the gas regulator and its hose. Therefore, Wireless Sensor Network (WSN) is one of the methods that suitable for detecting gas leakage in the wider area. This method uses two or more gas sensors to detect leakage in two or more locations around the gas tube and its distribution line. WSN system works based on gas sensor MQ-6 and wireless module Bluetooth HC-05. Explosion prevention system works based on alarm/buzzer, exhaust fan, and automatic gas regulator. If the gas leaks, the sensor will send its data wirelessly to Arduino. Then, explosion prevention system will be activated. The system will turn the alarm/buzzer on, automatically releases gas regulator, and neutralizes the air with the exhaust fan. Both systems will be fully controlled by Arduino platform.

Sudden pressure increases in the penstock or spiral case of a hydraulic turbine are the effect of sudden flow variation that occur during transient processes of type opening / closing or load rejection of the hydro unit. The consequence of the pressure rise in the spiral case and penstock is the water hammer phenomenon, whose effects can be devastating in some cases, up to breaking pipes and calamities produced in the area. This paper aims to analyze the method of calculation of the maximum pressure values that might occur in load rejection situations to a hydraulic turbine, in spiral case and in penstock, conditioned by the limiting of the values of the over speed and measures of limiting the increase in pressure in conjunction with limiting the increase in speed in these specific processes. As an example, we studied and analyzed the situation of a hydroelectric power plant equipped with a 7.8 MW Francis turbine without pressure regulator and the inflow surge. The results of analytical calculation overlaid on the experimental measurements performed during the performance tests of the hydro unit lead to the conclusion that the calculation algorithm proposed has been chosen correctly and the 2-stage closing law of the wicket gate promoted in this case is effective in such situations.

Pressure reducing valve is an extremely significant equipment of energy dissipation for the water supply by gravity with pressure reducing technology in hydropower stations, and which has a pronounced effect on the normal technical water supply even safety operation for the hydropower units. A three-dimensional numerical calculation of flow field and cavitation characteristics towards a combined type pressure reducing valves was carried out based on the system of technical water supply in this paper. The numerical results show that the investigated valve could meet the requirements of technological supply water pressure and great pressure loss was caused when the water flow was accelerated by narrow overflowing section between throttling cone and valve seat. At working operation, obvious cavitation phenomenon was observed on the surface of throttling cone, and the maximum volume fraction of vapor reached 0.537%. Based on above researches, this paper introduces an optimization model for profile line design of throttling cone. The optimal results show that the cavitation performance is effectively improved with identical pressure drop compared with original results.