Maintenance of centrifugal machinery in the chemical and petrochemical production is based, as a rule, on the application of the planned preventive maintenance (BPD). Repair of equipment for This is carried out in accordance with the schedule of cpd a year or more. A major shortcoming of this service is that each of the centrifugal machine has certain peculiarities design and operation, so its failure may occur long before the date of repair, planned in accordance with the spr, and vice versa, the equipment is often displayed in the repair of prematurely when the resource of its elements have not yet worked out. To ensure trouble-free operation of machinery with a simultaneous increase in its turnaround, as well as to reduce operating costs appropriate to transfer technology installation on-condition maintenance, ie, the system of planning and diagnostic repairs (SPDR). This article is devoted to problems of organization of operation, diagnosis and repair of centrifugal machine equipment of refineries on the technical condition. First of all, the article applies to maintenance of centrifugal compressor machines (CCM), centrifugal pump units (TsNA), centrifugal ventilation units (CVA), blowers, smoke exhausts, superchargers, air coolers, motors, drive turbines, operated in routine conditions. Maintenance and repair of machinery equipment maintenance as a single interconnected system, which includes: – every shift system maintenance, monitoring and recording of equipment, conducted on place of operation – the system of continuous and periodic monitoring of the characteristics that define the technical conditions – the system output in the repair and determine its extent on the parameters of technical condition of the centrifugal machines – a system of accumulation, analysis and processing of diagnostic information for the timing of the withdrawal in the repair and determine its volume. .
Tag Archives: promyshlennoct and equipment
Maintenance, Diagnosis And Repair Of Centrifugal Machines
OZS Electrodes
How does the type of coating electrodes with their welding characteristics. Ability to perform welding in any position, the performance of electric welding, welding current is required, the propensity to pore formation, and (in some cases) the tendency to form cracks in the weld and content in the weld metal hydrogen, all these factors directly depend on the type of coating welding electrodes. Sour cover consists of silicon, manganese and iron oxides. Electrodes coated with acid (CM-5, ANO-1), the properties of welded joints and weld metal are the types of E38 and E42. When welding electrodes coated with an acidic metal-coated rust or dross, will not form pores (the same, with lengthening of the arc). Welding current of these electrodes can be ac or dc.
Negative factor when welding electrodes is coated with an acidic high propensity to appear in the weld metal hot cracking. Ground electrode coating (UONII-13, DSC-50) is formed by fluorides and carbonates. The chemical composition of the metal, directed by such electrodes, identical became calm. Low content of nonmetallic inclusions, gases and contaminants ensures high weld metal toughness (at normal and low temperatures), and plasticity, it has high resistant to the appearance of hot cracks. According to its characteristics, and electrodes coated with the main relate to the types of E42A and E46A, E50A, and E60.
However, with basic coated electrodes are inferior to their technological characteristics certain types of electrodes because of its shortcomings, in the case of wet coating and with the lengthening of the arc to work with them high sensitivity to pore formation in the weld metal. Welding of these electrodes is performed under constant current with reversed polarity, the electrodes before welding require calcination (at t 250 420oS). Rutile electrode (MR-3, ANO-3, ANO-4, OZS-4) bypass for a number of technological qualities all other types of electrodes. When performing welding ac arcing electrodes such a powerful and stable, with minimal spray metal forming high-quality seam and peel easily separated from the slag. Changing the length of the arc welding wet or rusty metal and welding on the surface of oxides, all of which have little effect on pore formation rutile electrodes. However, they formed the weld metal has a negative quality, a lower impact strength and plasticity induced by the inclusions of silicon oxide. Organic ingredients in a large number (50%) is cellulose coating type electrodes (WCC-1, WCC-2, OMA-2). The weld metal is identical to calm them, or poluspokoynoy steel (chemical composition). According to its characteristics with cellulosic electrodes are types E50, E46 and E42. One-sided welding cellulosic electrodes on weight yields uniformly inverse sutural ridges, can be welded and the vertical joints; by upside down. However, in the resulting cellulosic electrode for welding seam metal high content of hydrogen and so; big minus.
Colorants And Additives For Plastics
In this article we look at painting and modification of polymeric materials using granulated concentrates and masterbatches. This method deserves attention because of its simplicity and its manufacturability application, as well as due to the fact that today more than 98% of the world's products from plastics to acquire the required physical and mechanical properties and color with these granules. Concentrates, or the so-called masterbatches represent granules containing functional or coloring additives and polymer as a binder. The manufacturing process of their production processes that use similar granulation. Material support (polymer matrix) and additives (usually in powder form) with the precise dosage mix with each other. The resulting mixture is homogenized worm extruder and pressed through forming equipment. To obtain pellets melt can be applied in two ways.
This granulation in the chilled spinneret or cutting the extruded strands granulkuterom. Coloring additives are made from the carrier material and colorants. Polymer matrix concentrate shall consist of the same material as the polymer and painted for high quality color distribution for the product. The term "colorant" is to be understood organic dyes and inorganic pigments, which gives the material the desired color. As inorganic pigments using carbon black, titanium dioxide, chromium oxides, iron oxide compounds, etc. They are finely divided and have been attributed to volume of the polymer, depending on Stepney opacity paint over the product. Unlike organic dyes is that they dissolve in the molten plastic, which can be left natural transparency polymer and give it the desired shade. As an example, pet bottles, a bluish tint which is purchased with help of the phthalocyanine dye. Mechanism for generating functional additives inherently is the same process, only instead of colorants used substances modifying the properties of plastics such as processability, transparency, luster (gloss), surface friction, impact strength, etc. Quality masterbatch mainly depends on the quality of used colorants and additives, as well as on compliance of production technology. This determines the color accuracy and uniformity derived properties of the product.
Disinfectants
Any inherent technological stages, and in particular food, the production – disinfection and cleaning. These two processes are closely related. Disinfectants used for disinfection of various surfaces and Prevention of infection by microbes food. Detergents are used to remove impurities of chemical origin. With the right as washing removes virtually 100% of dirt and bacteria. Follow disinfection bring that percentage up to 100%. Effective disinfectants must have low toxicity, broad spectrum antimicrobial activity, ease of use, versatility and long-term storage of concentrates and working solutions. There are some basic rules and criteria for the selection of disinfectants: 1.
Disinfectant must be corrosive (or slightly) low toxicity. Current disinfectant must not cause corrosion of metals and other damaging materials that are part of the equipment to maintain activity in the presence of organic substances, not to toxic and allergic effects. 2. Disinfectants should be of high quality, diverse and focused. The main objective for disinfectants – creating an effective, reliable protection from infections.
3. Disinfectant should be feasible. In the current economic conditions, reductions in the costs of industrial plants, food manufacturing, meat and dairy products, beverages itp, ceases sharply the question of cost and quality of disinfectants used to clean equipment. Typically, the best solution and the solution is to use multi-purpose cleaning and disinfectants. It is therefore necessary to choose fast, reliable and effective against yeast, bacteria, viruses, fungi, and spores. Detergent properties of disinfectants are to remove liquid and solid contaminants from the surface and transfer them to the washing liquid in the form of solutions. Detergent action is manifested in the complex processes of interaction of pollution, cleaning mediums and surfaces. The main phenomena determining detergent action, are the processes of physical and chemical adsorption, wetting, emulsification, foaming and stabilization. To obtain the desired effect of disinfection must be followed carefully prepare and use of disinfectants.
Connection Equipment
According to the principle of the spark gaps are divided into unmanaged and managed. Contact information is here: Daniel E Straus. In unmanaged dischargers breakdown occurs at a certain voltage values, depending on the design of the device. In managed – in a certain range of voltages at a pulsed voltage on the gate electrode. The advantages of spark gaps: no heat, virtually instantaneous willingness to work High reliability, small size and weight, Simple design and technology production. Disadvantages spark gaps: For tripping devices to the high value of the transmitted voltage (kV), which results in damage to the equipment being protected.
The intensity of the spark occurring in the while conducting state, often causes interference and leads to a malfunction of nearby electrical equipment. Residual currents lead to disruptions in power and, therefore, unpredictable in the equipment. Parallel Connection of varistors. Varistor Eng. varistor, from vari (able) – ac and (resi) stor – resistor, a semiconductor resistor, the electrical resistance (conductivity), which does not vary linearly and equally under the influence, both positive and negative voltage. For the manufacture of varistors used powdered silicon carbide (semiconductor) and a binder (clay, water glass, paints, resins, etc.) are pressed into shape and sintered it at a temperature of about 1700 C.
Then the sample surface metallized and soldered to its findings. Low-voltage varistors are made on the operating voltage of 3 to 200 V and current of 0,1 mA to 1 A; High-on voltage to 20 kV. Advantages: Varistors have a negative temperature coefficient of resistance, able to withstand considerable electrical overload Easy and cheap, have high reliability, low inertia (limiting the operating frequency to 500 ).