Research of the Microstructure of the Deposited Layer during Electric Arc Surfacing with Control Impacts

2021 ◽  
Vol 1038 ◽  
pp. 85-92
Author(s):  
Vitaliy Ivanov ◽  
Elena V. Lavrova ◽  
Vladyslav Kibish ◽  
Ihor Mamontov
Keyword(s):  
Complex Shape ◽  
Production Equipment ◽  
Electric Arc ◽  
Operating Conditions ◽  
Metallurgical Production ◽  
Aggressive Environment ◽  
Working Surface ◽  
Slag Inclusions ◽  
Deposited Metal ◽  
The Cost

Electric arc surfacing is widely used for the application of protective and restorative coatings on units and parts of metallurgical production equipment in order to increase their durability in harsh operating conditions and in an aggressive environment. Increasing the efficiency of melting the electrode material is an important task, since it allows one to reduce the required volume of deposited metal and the cost of surfacing. In addition, when surfacing by traditional technology of parts with a complex shape of the working surface, it was found that the deposited layer can contain such defects as single gas and line pores, as well as slag inclusions. The work is devoted to the study of improving the surfacing technology by controlling heat input into the base metal using controlled mechanical actions.

scholarly journals Alloying working surface during electroslag surfacing

2021 ◽  
pp. 17-21
Author(s):  
V. G. Komkov ◽  
◽  
S. A. Gubar ◽  
G. G. Voskresensky ◽  
◽  
...  
Keyword(s):  
Service Life ◽  
Abrasive Wear ◽  
Slag Bath ◽  
Direct Introduction ◽  
Finished Part ◽  
Working Surface ◽  
Short Service Life ◽  
Deposited Metal ◽  
Scheelite Concentrate ◽  
The Cost

Parts subject to intense abrasive wear have a short service life. In the manufacture or restoration of such parts by electroslag surfacing, strengthening of the deposited metal is required. The use of ready-made alloying powders in surfacing increases the cost of the finished part, which necessitates the search for cheaper materials for alloying the parts being welded. The study of the efficiency of alloying the deposited metal through the melted insert, as well as by direct introduction of alloying powders into the slag bath has been carried out. Mixtures based on enriched mineral scheelite concentrate and graphite are used as alloying powders

CAD Of Anticorrosive Protection Of Steel Structures

2019 ◽  
pp. 18-23
Keyword(s):  
Protective Coating ◽  
Computer Aided Design ◽  
Steel Structures ◽  
Cost Effective ◽  
Operating Conditions ◽  
Computational Tool ◽  
Protection Method ◽  
Cost Effective Method ◽  
The Cost ◽  
Aided Design

The choice of cost-effective method of anticorrosive protection of steel structures is an urgent and time consuming task, considering the significant number of protection ways, differing from each other in the complex of technological, physical, chemical and economic characteristics. To reduce the complexity of solving this problem, the author proposes a computational tool that can be considered as a subsystem of computer-aided design and used at the stage of variant and detailed design of steel structures. As a criterion of the effectiveness of the anti-corrosion protection method, the cost of the protective coating during the service life is accepted. The analysis of existing methods of steel protection against corrosion is performed, the possibility of their use for the protection of the most common steel structures is established, as well as the estimated period of effective operation of the coating. The developed computational tool makes it possible to choose the best method of protection of steel structures against corrosion, taking into account the operating conditions of the protected structure and the possibility of using a protective coating.

Application of plasma-powder and electric arc coatings to increase tribocorrosion resistance of steels in aggressive environment

2020 ◽  
Vol 2020 (8) ◽  
pp. 20-26
Author(s):  
V.I. Pokhmursky ◽  
◽  
M.S. Khoma ◽  
I.O. Ryabtsev ◽  
Ye.F. Pereplyotchikov ◽  
...  
Keyword(s):  
Electric Arc ◽  
Aggressive Environment

Optimal Placement of FACTS Devices for Voltage Stability Improvement with Economic Consideration Using Firefly Algorithm

2019 ◽  
Vol 14 (1) ◽  
pp. 5-11
Author(s):  
S. Rajasekaran ◽  
S. Muralidharan
Keyword(s):  
Power Systems ◽  
Voltage Stability ◽  
Firefly Algorithm ◽  
Transmission System ◽  
Operating Conditions ◽  
Optimal Placement ◽  
Voltage Collapse ◽  
Facts Devices ◽  
The Cost ◽  
Bus System

Background: Increasing power demand forces the power systems to operate at their maximum operating conditions. This leads the power system into voltage instability and causes voltage collapse. To avoid this problem, FACTS devices have been used in power systems to increase system stability with much reduced economical ratings. To achieve this, the FACTS devices must be placed in exact location. This paper presents Firefly Algorithm (FA) based optimization method to locate these devices of exact rating and least cost in the transmission system. Methods: Thyristor Controlled Series Capacitor (TCSC) and Static Var Compensator (SVC) are the FACTS devices used in the proposed methodology to enhance the voltage stability of power systems. Considering two objectives of enhancing the voltage stability of the transmission system and minimizing the cost of the FACTS devices, the optimal ratings and cost were identified for the devices under consideration using Firefly algorithm as an optimization tool. Also, a model study had been done with four different cases such as normal case, line outage case, generator outage case and overloading case (140%) for IEEE 14,30,57 and 118 bus systems. Results: The optimal locations to install SVC and TCSC in IEEE 14, 30, 57 and 118 bus systems were evaluated with minimal L-indices and cost using the proposed Firefly algorithm. From the results, it could be inferred that the cost of installing TCSC in IEEE bus system is slightly higher than SVC.For showing the superiority of Firefly algorithm, the results were compared with the already published research finding where this problem was solved using Genetic algorithm and Particle Swarm Optimization. It was revealed that the proposed firefly algorithm gives better optimum solution in minimizing the L-index values for IEEE 30 Bus system. Conclusion: The optimal placement, rating and cost of installation of TCSC and SVC in standard IEEE bus systems which enhanced the voltage stability were evaluated in this work. The need of the FACTS devices was also tested during the abnormal cases such as line outage case, generator outage case and overloading case (140%) with the proposed Firefly algorithm. Outputs reveal that the recognized placement of SVC and TCSC reduces the probability of voltage collapse and cost of the devices in the transmission lines. The capability of Firefly algorithm was also ensured by comparing its results with the results of other algorithms.

Electro-Fenton as a feasible advanced treatment process to produce reclaimed water

2004 ◽  
Vol 50 (2) ◽  
pp. 83-90 ◽  
Author(s):  
A. Durán Moreno ◽  
B.A. Frontana-Uribe ◽  
R.M. Ramírez Zamora
Keyword(s):  
Reclaimed Water ◽  
Electrical Current ◽  
Primary Treatment ◽  
Operating Conditions ◽  
Treatment System ◽  
Continuous Reactor ◽  
Fenton’S Reagent ◽  
Fenton's Reagent ◽  
Fenton’S Reaction ◽  
The Cost

The feasibility of the electro-Fenton process to generate simultaneously both of the Fenton's reagent species (Fe2+/H2O2), was assessed as a potentially more economical alternative to the classical Fenton's reaction to produce reclaimed water. An air-saturated combined wastewater (mixture of municipal and laboratory effluents) was treated in discontinuous and continuous reactors at pH = 3.5. The discontinuous reactor was a 2 L electrochemical laboratory cell fitted with concentric graphite and iron electrodes. The continuous reactor tests used a pilot treatment system comprising the aforementioned electrochemical cell, two clarifiers and one sand filter. Several tests were carried out at different conditions of reaction time (0-60 min) and electrical current values (0.2-1.0 A) in the discontinuous reactor. The best operating conditions were 60 min and 1 A without filtration of effluents. At these conditions, in discontinuous and continuous reactors with filtration, the COD, turbidity and color removal were 65-74.8%, 77-92.3% and 80-100%, respectively. Fecal and total coliforms, Escherichia coli, Shigella and Salmonella sp. were not detected at the end of the pilot treatment system. Electrogeneration of the Fenton's reagent is also economical; its cost is one-fifth the cost reported for Advanced Primary Treatment.

Effects of Cycle Operating Conditions on Combustor Performance

1997 ◽  
Vol 119 (1) ◽  
pp. 45-49 ◽  
Author(s):  
N. T. Davis ◽  
V. G. McDonell ◽  
G. S. Samuelsen
Keyword(s):  
Cost Function ◽  
Duty Cycle ◽  
Load Condition ◽  
Combustion Efficiency ◽  
Operating Conditions ◽  
Nox Emissions ◽  
Variable Geometry ◽  
Oxides Of Nitrogen ◽  
Mixing Processes ◽  
The Cost

To mitigate the environmental impact of next-generation gas turbine combustors, the emission performance at each condition throughout the load duty cycle must be optimized. Achieving this with a single combustor geometry may not be possible. Rather, the mixing processes and airflow splits must likely be modified as a function of load in order to (1) abate the emission of oxides of nitrogen, (2) maintain combustion efficiency, and (3) preclude lean blow-out over the entire duty cycle. The present study employs a model combustor to evaluate combustor performance as a function of load and explore the application of variable geometry to optimize performance at each condition. A parametric variation of flow splits is conducted at each load condition by independently adjusting the primary jet area and swirler choke area. The resultant impact on combustor performance is measured and quantified in terms of a cost function. The cost function is defined to increase with improving combustor performance (e.g., improving combustion efficiency and/or declining NOx emissions). Cycle operating conditions are found to alter the response mappings of efficiency and NOx. As a result, the optimal configuration of the combustor changes as the load is varied over the duty cycle. The results provide guidance on the application of active control.

scholarly journals Application of the optimally alloyed cast irons in order to increase the durability and to ensure the cost reduction of mining and metallurgical products

2021 ◽  
Vol 303 ◽  
pp. 01005
Author(s):  
Dmitry Lubyanoi ◽  
Evgeny Pudov ◽  
Evgeny Kuzin ◽  
Olga Semenova
Keyword(s):  
Wear Resistance ◽  
Cast Iron ◽  
Operational Reliability ◽  
Cast Irons ◽  
Metallurgical Production ◽  
Alloyed Cast ◽  
Alloyed Cast Iron ◽  
And Performance ◽  
Working Bodies ◽  
The Cost

The article shows the relevance of the use of alloyed cast iron in mining and metallurgical engineering. The article discusses the technologies for producing naturally alloyed cast iron. For working bodies and friction units of mining machines, such as pumps, coal pumps, hydrocyclones, crushers and mills. The main type of wear for them is abrasive. To increase the wear resistance of cast iron the production of cast iron has not been sufficiently studied yet. Although the use of cast iron in a complex alloyed with manganese, silicon, chromium, titanium and vanadium has been studied. The article studies the influence of manganese, titanium and vanadium on the mechanical properties and performance of machine parts and products of mining and metallurgical production in contact with high-temperature and highly abrasive media. The rational content of titanium and vanadium in gray cast irons is established in the range of 0.05-0.1%, which ensures their heat resistance and increases their wear resistance. The content of these elements can be increased to 0.07-0.12%. Bushings made of this cast iron have the required wear resistance and can increase the operational reliability of the equipment in the conditions of mining and metallurgical production. They also replace non-ferrous metals, as well as products obtained by powder metallurgy methods.

scholarly journals EFFECTIVENESS EVALUATION OF STEEL STRENGTH IMPROVEMENT FOR PYRAMIDAL-PRISMATIC BUNKERS

2020 ◽  
Vol 2 ◽  
pp. 30-38
Author(s):  
Yukhym Hezentsvei ◽  
Dmytro Bannikov
Keyword(s):  
Low Temperatures ◽  
High Strength ◽  
Operating Conditions ◽  
Professional Literature ◽  
Plastic Properties ◽  
Repair Work ◽  
Practical Engineering ◽  
Cis Countries ◽  
The Right ◽  
The Cost

In accordance with the recommendations of specialized professional literature, steel pyramidal-prismatic bunkers are projected for a service life of 20 years. However, in practice this term is often twice, or even three times lower. This is especially true for complicated operating conditions, in particular the effect of increased loads and low temperatures. Existing design techniques for such structures, both in European practice and the design practice of Ukraine and other CIS countries do not pay attention to these aspects. Therefore, in the practice of operation, the increased accident rate of steel bunker capacities has already become virtually a common occurrence. One of the possible ways to solve this problem is presented, which consists of using instead of traditional steels of ordinary strength with high plastic properties, steels of increased or high strength with reduced plastic properties. At the same time, clear theoretical recommendations are provided for choosing the right steel depending on the operating conditions, primarily when exposed to increased loads. The recommendations are presented in a form convenient for practical engineering applications. The proposed approach allows to reduce the material consumption of structures of this type on average according to theoretical estimates by 25-30% without reducing their bearing capacity. Their durability is also further enhanced by improving performance at low temperatures. Thus, the applied aspect of such a solution to this above problem is the possibility of increasing the overall reliability of steel bunker capacities, as well as reducing the cost of their periodic maintenance and repair work. A practical illustration of the presented approach is also given on the example of the design of bunkers of a bypass track for supplying charge materials for blast furnaces of one of the metallurgical plants of the northern location. As a result, this created the preconditions for monetary savings of about 0.5 million UAH in prices 2019 (about 20,000 USD)

Method for calculating the thrust and specific thrust of a double-flow gas turbine engine based on the results of tests at the laboratory unit «Flame»

2021 ◽  
pp. 58-64
Author(s):  
S.M. Sergeev ◽  
◽  
V.A. Kudriashov ◽  
N.V. Petrukhin ◽  
◽  
...  
Keyword(s):  
Gas Turbine ◽  
Gas Turbine Engine ◽  
Operating Conditions ◽  
Similarity Criteria ◽  
Fuel Quality ◽  
Jet Engines ◽  
Laboratory Unit ◽  
Turbine Engine ◽  
Specific Thrust ◽  
The Cost

The main technical characteristics of jet engines depend on the fuel quality: thrust and fuel consumption. As a rule, the comparative assessment of real engines is carried by specific values. Specific thrust is one of the most important parameters of the gas turbine engine (GTE). The larger it is, the smaller the required air flow rate through the engine at a given thrust and therefore its dimensions and mass. To date, a system for evaluating the performance properties of fuels based on qualification methods has been created. However, these methods do not allow calculating the thrust and specific thrust of the engine and potentially assessing the effect of fuels on these characteristics. Therefore, the issues of efficient use of fuels for GTE are solved almost exclusively on the basis of tests at testing units with full-scale engines, which are carried out repeatedly, which leads to a significant increase in the cost of testing. The article proposes a method for calculating the thrust and specific thrust of a double-flow gas turbine engine according to the results of tests at a constant volume laboratory unit of bypass type “Flame”. The method is based on modeling the engine operating conditions using the similarity criteria of the bench reactor and the real engine and allows reducing significantly the material and time costs for testing. The experimental of the combustion characteristics of hydrocarbon fuels and the rated values of their thrust and specific thrust for a double-flow gas turbine engine are presented.

Fuel Cell Microgrid with Wind Power Generation

2014 ◽  
pp. 136-166
Keyword(s):  
Power Generation ◽  
Fuel Cell ◽  
Wind Power ◽  
Dynamic Characteristics ◽  
Operating Conditions ◽  
Wind Power Generation ◽  
Small Scale ◽  
Power Characteristics ◽  
Renewable Power ◽  
The Cost

This chapter consists of two sections, ‘Analysis of a Fuel Cell Microgrid with a Small-Scale Wind Turbine Generator’ and ‘Power Characteristics of a Fuel Cell Microgrid with Wind Power Generation.’ An independent microgrid is expected to be effective in cutting greenhouse gas discharge and energy costs. Therefore, the operating conditions of an independent microgrid that supplies power with renewable power sources and fuel cells are investigated in the 1st section. In the 2nd section, the dynamic characteristics of fuel cell microgrid are investigated in numerical analysis, and the cost of fuel consumption and efficiency is also calculated. In addition, the stabilization time of the microgrid and its dynamic characteristics accompanied by wind-power-generation and fluctuation of the power load are clarified.

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