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文献翻译1. Design of small mixerAbstract:Mixing equipment has a long history, a wide range of applications. Widely used in chemical industry, petroleum industry has, the construction industry and traditional industry. Mixing operation appears to be simple, but in fact, it involved are extremely complex. This paper introduces the basic ideas of small pulsator design and basic theory, analyzes the basic structure of stirrer and related contents of motion and power device. The basic equipment of stirrer description and references of its basic principle, function and operation, and design for the small mixer were reviewed.1.1 The graduation project of the purpose, significance, current situation of domestic and foreign 1.1.1 graduation design topic research purpose, significanceAgitator making chemical reaction is to make the role of the agitator in chemical production liquid mixing, chemical reaction can be carried out to meet the greatest degree of. The device can replace the manual stirring toxic to the human body or harmful chemical raw material, the skin has the advantages of simple structure, convenient use, wide application in chemical production. This paper designed a small mixer, about 500 liters in volume, stable and flexible, easy to use. This topic mainly relates to equipment design of agitator in chemical production, mainly to solve the problem of the design, the equipment in chemical production include: agitator selection, motor and reducer selection, support device design, shaft seal, selection and setting tank design, and draw the corresponding equipment1.1.2 History and development status of agitatorMixing equipment is widely used as a kind of fluid machinery products, wide variety, suitable for chemical industry, metallurgy, medicine, food and feed industries. Mixing operation is an important link in the industrial process, which involves fluid mechanics, heat transfer, mass transfer and chemical reactions and other processes, and the stirrer is in order to make the mixing media device is suitable for the flow field and the input mechanical energy to it. The mixer is also called Mixer, or Agitator, Stirrer. Also includes the solid particles suspended in the solution or the solution into emulsion evenly stirred broad, it includes the disperser and homogenizer. Some stirrer can produce shear force greatly, to obtain refined particle colloid mill more than 10 times larger than the submicron suspension, therefore, can be used for fine food and chemical manufacturing, cosmetic cream, salad sauce. Petrochemical industry is commonly used in polyvinyl chloride alloy, CIS polybutadiene rubber in autoclave, autoclave, stripping vessel, collectively referred to as the mixing vessel (Agitatored Vessels, or Stirred Vessels).Stirrer and stirring container in device of economies of scale and diversification of varieties at the same time, it become more and more large. Since Hitachi production since 1949 the production of stirred tank reactor for terephthalic acid, polyvinyl chloride, styrene monomer, the polypropylene unit production of the stirred tank reactor near 4000, the maximum capacity of the container to 576m, maximum diameter of 7620 cylindrical part mm, the maximum length of making 44380 mm design pressure, maximum 28 the design of MPa, the highest temperature making 530 cI two, motor power up to 1100 kW. Based on the requirements of the development of energy saving, variable frequency motor, seal small shear resistance blade, with new sealing instead of mechanical seals and packing, with magnetic drive instead of mechanical transmission. Reduce product cost, reduce the cost of the overall repair and maintenance and improve equipment repair requirements based on the average time interval, greatly improving the service life of equipments. To meet the health and reduce the cleaning and sterilization costs based on the requirements, implementation of the CIP (clean in place) and SIP (in situ sterilization), improve the level of automation, avoids human contact with the product, reduce manual operation and standby time, greatly improving the products health level.The main types of 1.1.3 agitator and its developmentAccording to the stirrer shape can be divided into straight blade turbine type, open type, push type, disk turbine type, anchored, spiral, spiral type; according to the different liquid viscosity can be divided into low viscosity fluid mixer, medium high viscosity liquid agitator. Low viscosity fluid mixer, such as: trefoil push type impeller, blade paddle (2 to 60 percent off leaves), 6 straight blade turbine type, super hybrid impeller type (HRO0, HV200),; high viscosity liquid mixer such as: anchored, screw impeller, double helical ribbon impeller type, super mixing agitator (MR205305) etc. In order to achieve high precision, high quality requirements, in foreign countries, especially Japan developed a stirring device model, in order to meet the need of production of high viscosity products. Such as the inverted conical spiral wing type mixer, mixer, ultra high performance floating stirred tank, super vibration alpha type agitator.In the mixing operation to the material, the people hope to realize various agitation purpose, so to understand the characteristics of various stirrer impeller type, choose appropriate, design stirrer with flow characteristic is very important. In a stirred tank of liquid to flow characteristics of three-dimensional flow, in order to distinguish the stirring blade discharge, according to the main drainage direction, according to the cylindrical coordinate the typical blade into radial flow impeller and axial flow impeller. Tooth type, flat leaf pulp type, straight blade disk turbine type and the curved blade turbine type in Unbaffled Stirred Tank in addition to make the liquid to produce a rotating together with the impeller circumferential flow, also due to the centrifugal impeller is along the blade to the tank wall liquid injection, forming radial strong making strong flow, so these the impeller is a radial flow impeller. Radial flow impeller agitator rotates, the material is axial suction and radial impeller discharge, large power consumption, stirring speed, shear strength. As shown in Figure 3, shown in Figure 4, is a typical radial flow impeller. In the turbulent state, promote the impeller in addition to produce circumferential flow, also have a large number of axial flow, is typical of the axial flow impeller. The blade turbine impeller compared with straight blade turbine and curved blades impeller axial flow turbine, more components, used for axial flow. Ribbon and screw impeller made of high viscosity material produce axial flow, also is the axial flow impeller. Axial flow impeller agitator no partition cycle, unit power generation flow, shear rate is small and evenly distributed on the blade near a large range, with a strong maximum anti off current capability. As shown in Figure 5, Figure 6 shows, is typical of the axial flow impeller.Under normal circumstances, mixing equipment widely used in hybrid low viscous and solid-liquid suspension of operation, the impeller axial circular flow requirements can provide high with low energy consumption. Because the traditional push type blade for three-dimensional surface complex, can meet the requirements, but the manufacture is difficult, not easy to large scale. Therefore, to develop energy efficient, low cost and easy to large-scale second generation high performance axial flow agitator to become Mixing Equipment Company target. America lightnin company developed A310 and A315 series (as shown in Figure 7, figure 8).Professor Shen Huiping China et al Institute of petrochemical technology has developed a new high efficient and easy processing of axial flow impeller. It is a space warp sheet type blade, the blade tip, which is composed of many similar arches, and the radius, and blade angle, reasonable camber and leaf width. Model mixing equipment makingHorizontal in recent years Europe and the Et developed many suitable for high viscosity and high viscous self-cleaning mixing equipment. The horizontal double phase (AllPhase) type mixer is a typical example. Figure 12 shows.In addition, the Beijing Yanshan Petrochemical Co., Ltd. Design Institute in large diameter, low speed, medium thick occasions, design of a composite type agitator, solves the motor can not be equipped with large power, problems existing in manufacturing, maintenance and installation difficulty. Composite structure of agitator is shown in figure l3. The making making making equipment intelligent design.According to the expert experience and knowledge, the mixing equipment and automatic control technique, using artificial intelligence technology in the mixing equipment selection and design (AJ) and knowledge based system (KBS), namely the mixing equipment selection and design of the intelligent.As is shown in figure 14,Mixing equipment design expert system using the total design task control in each stage of design task, task scheduling corresponding design knowledge and data, realize the organization method of expert system design of mixing equipment. Through careful analysis, attribution, intelligent design system prototype stage to realize the design process of mixing equipment, it can be said that the chain sequence for the design of a series of processes. Each stage of relatively independent and continuous to each other, wherein each design stage will be transferred to the successor structure design process of L6j. The system analysis and evaluation, from the selection of impeller of process design, mechanical design and economic, to the final mechanical drawing are given a intelligent computer aided design. It can be applied to the Newton fluid and non Newton fluid, liquid liquid system, solid a fluid system and a fluid system, and can be applied system processing volume more than 100 cubic meters. In twentieth Century 90 years, mixing equipment selection and design of the expert system has been few reported abroad. 图141.1.4 conclusion makingMixing operation is an important part of industrial reaction process, mixing equipment in the chemical industry plays a very important role. Modern chemical industry requires mixing technology better, it is necessary to improve the traditional stirring device, development of new mixing equipment; at the same time the use of LDV, PIV and EPT advanced measurement technique, using computational fluid dynamics knowledge, in-depth analysis of mixing mechanism of liquid flow in the reactor and micro mixing, safety and optimal design to improve the efficiency of the process, performance and reduce the risk of failure, and ultimately improve the reaction yield. In the promotion of the modern advanced technology, mixing technology will develop to a new stage.1.2 Working principle of mixerUsually the mixing device comprises a motor as the prime mover (electric, pneumatic or hydraulic), reducer output shaft connected with the pumping and stirring, and installed on the impeller shaft component slow body through a bracket or the bottom plate and the mixing vessel. When the vessel internal pressure, stirring shaft passes through the floor into the container shall have a common seal, packing seal or mechanical seal. Usually the motor and sealing are purchased, the focus of the study is the impeller. Stirring impeller performance as pumping and vortex , which produce the fluid velocity and fluid shear, reflux, the former lead to full container medium translocation, prevent solid precipitation and generate heat exchanger heat tube (if any) erosion; shear is a high return in the micro mixing, the droplet can break the bubbles or insoluble, resulting in uniform.1.3 Mixing equipment in chemical reactionAccording to the impeller shape can be divided into straight paddle, open turbine type, push type, disk turbine type, anchored, spiral, spiral type according to the processing liquid bull degree can be divided into low viscosity fluid mixer. Low viscosity fluid mixer, such as: trefoil propelled, folded leaf blade, 6 straight blade turbine type, super hybrid impeller type HR 100, HV 100,; high viscosity liquid mixer such as: anchored, screw impeller, double helical ribbon impeller type, MR 205305 super mixer etc.1.4 To adapt to the conditions and structure of chemical agitator1.4.1 To adapt to the conditions of chemical agitatorStir to speed up the heat and mass transfer, widely used in chemical equipment. The chemical agitator in chemical production liquid mixing, chemical reaction can be carried out to meet the greatest degree, the device can replace the manual stirring toxic to the human body or harmful chemical raw materials to reduce the harm to human body skin, at the same time, driven by the motor shaft speed stirring, improve productivity. Stirring accelerated heat and mass transfer, widely used in chemical equipment. Agitation of the object can be liquid, solid and gas, where liquid is essential. The most common liquid is water, the viscosity is very low. The liquid may also very sticky, such as butter at room temperature for up to 000000 L, cP. Such as adding liquid in the solid, such as sediment, lose liquidity, become the. This kind of material can be stirred, but not in the scope of this paper.1.4.2Tectonic chemical agitatorIn process of chemical production, agitator types usually use a paddle agitator, turbine type agitator, propeller type stirrer, anchor agitator, frame type stirrer, ribbon agitator etc. Various types of mixer because of its structure, performance differences, which can be respectively applied to various chemical production in different conditions. Propeller type stirrer can be divided into straight blade and blade agitator two. The structure and processing of the stirrer are relatively simple.1.5 design theEquipment and method of this research can be divided into the following steps1: according to the requirement of design available D / T (the diameter of the wheel / tank diameter) value, and the mixing time, mixing degree requirements, select several different speed torque or power requirements2: selected reasonable impeller mounting height, binding equipment, estimate the stirring shaft length; 3: estimate the motor power reasonable4: according to the impeller power. The output shaft, bracket and so on, can meet the requirements of the agitator selection before three; 5: according to tip tangential speed conditions, determine the most appropriate speed, to optimize the design, according to the established conditions, checking and analysis of factors of power and strength of the shafting.2 Design of stirred vesselAccording to the design requirements, requirements of agitator about 500 liters in volume, viscosity of liquid 0.3Pa.s, liquid density =1500kg/m3, speed of 40r/min, v=5m/s. Combined with the actual conditions, this paper selects cylinder agitator. The shell design of agitator into the cylindrical, agitator rotation, transmitting mechanical energy to the fluid, high turbulent mixing region is formed in the stirrer, and generates a high speed jet flow, the fluid pressure head high, push the liquid circulation flow in stirred vessel. In the guidance of cylinder, medium from the simplified top and bottom into the barrel, the completion of a cycle, make medium high speed radial flow and axial flow, and increase the medium flow rate, medium flow more uniform.3. To determine the overall design scheme and dynamic component selection3.1 The overall design schemeIn process of chemical production, agitator types usually use a paddle agitator, turbine type agitator, propeller type stirrer, anchor agitator, frame type stirrer, ribbon agitator etc. Various types of mixer because of its structure, performance differences, which can be respectively applied to various chemical production in different conditions. Agitator is the low viscosity, low speed, liquid - liquid mixed small power equipment, the volume is 500L, according to the agitator requirements of these factors, this design selects the helical agitator. Inclined paddle agitator structure, blade and the stirring shaft installation angle 90 , the rotary stirring, resistance to alkali; on the other hand, inclined blade rotation can make the liquid material in the container to form a vortex, good stirring effect, especially when the shaft rotates in the forward direction, can precipitate agitation. Turn, pretty good on the stirring effect material; when the shaft rotates in reverse, and the suspension stirred to the bottom, stirring of liquid with suspended matter is favorable. But by the compound effect of shaft torque and bending moment, the strength, to cut the degree requirements and installation of the higher, more for low speed, low viscosity, small power (= 3040r / min) Comply with the design requirements.3.2 Design and calculation of stirrer and transmission device etc3.2.1 Select agitatorAccording to the technical requirements, selection of diameter 800mm, agitator shaft diameter 55mm, mark symbol for selection 800 - 55 3.4.2 motorAccording to the installation mode structure and motor stirrer, we use Y series V1 type vertical motor, motor model Y132S - 4 synchronous speed making making 1500 r/min rated power making making 5.5KW full speed making making 1440r/min maximum torque making making 2.2 quality making making making making 68KgThe structure dimensions refer to mechanical design course design manual table 12 - 5.3.2.2 reducer selection deviceAccording to the present situation in China, vertical speed reducer used in the reactor are mainly, cycloid pin wheel reducer, two gear reducer, V reducer, worm reducer, the reducer is several, several industrial departments concerned have standard series, according to the design and check the manual, we choose the cycloid pin wheel reducer, as shown below.According to the single fulcrum frame (HG21566 - 95) standard in the appendix has the commonly used kettle gearing reducer model and technology to choose the reducer models according to the nominal diameter and the stirring shaft speed. We use the BLD3 - 1 - 29Q type reducer. The installation size reference chemical equipment design basis table 18 - 12 (a)3.2.3 Bearing selectionBearings are important parts of the machine, its function is mainly a supporting shaft and shaft parts, and the shaft rotation accuracy, reduce the friction between the shaft and the bearing and wear. Work normally, friction resistance of rolling bearing sliding bearing is small, the power loss is small, easy to start, lubrication and maintenance is simple, and the rolling bearing is standard, by the specialized factory mass production, convenient selection. It is widely used in various mechanical equipments. So the design of the rolling bearing.Rolling bearings are usually composed of four components, namely, the outer ring, inner ring, rolling body 1 3 and 4 2 holder, as shown below. The outer ring and the inner ring raceway are of a certain shape, so as to ensure the accurate operation of the rolling body in the meantime. The rolling body is spherical, cylindrical, conical, needle shaped, the holder of the rolling body spaced apart from each other and uniformly distributed along the inner ring raceway, usually assembled in the shaft neck, rotates with the shaft; the outer ring is arranged in the bearing seat does not rotate. Because the contact area of rolling body and inner ring, outer ring is very small, the contact stress is large, they are made of alloy steel, after heat treatment the hardness reaches above 60HRC, cage multi-purpose mild steel stamping, useful also steel alloy, plastic and other materials.According to the size, direction and character of bearing load, we use a deep groove ball beari
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