畢業(yè)設(shè)計-單梁橋式起重機設(shè)計
資源目錄里展示的全都有,所見即所得。下載后全都有,請放心下載。原稿可自行編輯修改=【QQ:401339828 或11970985 有疑問可加】
河南理工大學萬方科技學院本科畢業(yè)論文翻譯
The history of crane
A significant word for the decade as far as the crane industry was concerned, was railways, as cranes for this industry were still very important. On 7 September 1949, for example, the Deutsche Bundesbahn (Federal German Railway) was founded. It needed high-capacity lifting devices that could be taken to the job site as part of a train. Four steam-driven cranes, each of which could lift 57 tonnes, were ordered from Ardelt. In 1950 followed a special type of crane with a boom designed for working below overhead wires. The cranes featured a counterweight attachment system which was connected to the lifting gean This innovative design did not prove successful, but was replaced in 1955/56 by a similar hydraulic mechanism. Also in Germany, MAN had been actively building not just harbour, dockyard and travelling cranes, but also diesel-powered slewing cranes with pneumatic steering. These had been built since 1946 (picture 204), were driven by a 70 kilowatt six cylinder truck engine and could lift 6 tonnes at 7 metres radius and weighed 48 tonnes. A small concession to safety was also introduced as the company brochure tells us: "A load moment safety device, built in to the boom mechanism and thus linked to the lifting mechanism, cuts in if the permitted load moment is exceeded". The brochure writer realised the significance of the fact that the device acted when the load was exceeded and not "... as was the case ten years ago, at the point when the superstructure has already tipped over!”These load moment safety devices,although a small part of the overall crane,were very important in the development ot the cranes.
Bridge crane
Bridge crane is horizontal plane in workshop, warehouse and yard over rigger materials of lifting equipment. Because of its ends located in tall cement posts or metal stents, shape like bridge. Bridge crane along the bridge on both sides laying in elevated the orbit of longitudinal operation, can make full use of the space below girder hoisting materials, does not suffer ground equipment obstacles. It is to use the widest range, the largest number of a kind of hoisting machinery.
Bridge crane is the modern industrial production and lifting transportation in realizing realize mechanization, automation production process to important tools and equipment. So bridge crane in interior industrial and mining enterprises, steel chemical industry, railway transportation, ports and logistics departments and establishments are widely used.
Bridge crane can be divided into ordinary bridge crane, simple girder crane and metallurgical special bridge crane 3 kinds. Ordinary bridge crane is general by lifting trolley and bridge operation organization, bridge metal structure group into. Lifting car again by lifting mechanism, trolley mechanism and the car frame of three parts. Lifting mechanism including motor, brakes, reducer, drum and pulleys. Driving speed reducer, electromotor through reel rotation of wire rope around the drum drum down, or from lifting weights with. Car frame is a torre and installation of hoisting mechanism and the car mechanism, etc. Parts of the frame, usually for welding structure. Crane operation organization drive mode can be divided into two kinds: one kind is concentrated drive, which is a motor driving long shaft drive on both sides of the active wheels, Another kind is respectively driven, namely on both sides of the active wheel each with a motor drives. Medium and small bridge crane is increasingly used brakes, reducer and electric generator synthetic one of three-in-one drive mode, a big weight of ordinary bridge crane for ease of installation and adjustment, device drivers often adopt universal shaft coupling. Crane operation organization generally in four active and driven wheels, if lifting weight is very big, commonly used to increase the wheel to reduce the pulley. When more than four wheels when, must use hinged equilibrium frame device to make the crane load evenly distributed in each wheel. Bridge of metal structure composed by main girder and girders, divided into the single girder frame and main double girder frame two kinds. Single main girder bridge girder and frame is located in single span on both sides of the girders composition, double girder frame girder by two root and girders composition. Girder and girders rigid connection, girders, supporting both ends with wheels in elevated bridge to run on. The main welding have orbit, for lifting car running. Bridge girder structure type more comparatively typical have box structure, four truss structure and open-web truss structure. Box structure can divide again on track box shuang liang, slant rail box shuang liang, slant rail box single girder to wait for a few kinds. Track box shuang liang is widespread adoption of a basic form the girder, consists of flange plate and bilateral vertical webs composition, car rail decorate in the center of the flange plate online, its simple structure, easy fabrication, suitable for mass production, but self-respect greatly. Partial rail box double beam and partial rail box single main section is by the upper and lower flange plate and the different thickness of the Lord vice webs composition, car rail decorate in the main webs, short circuits inside above stiffening plate can save, including partial rail box girder is composed of a single root box girder wide flange instead of two root girder, respect smaller, but manufacturing complex. Four truss structure featured by four plane truss by combined into closing in on the spatial structure, the level of general shop to have walked surface truss bedplate, light dead weight, stiffness big, but compared with other structure size, shape, manufacturing is relatively complex, fatigue strength low, has less production. Open-web truss structure similar to slant box girder by rail, four plates form a closed structure, in addition to the main webs for real abdomen i-section beam outside, the rest 3-piece plate according to the design demand cutting into many window, forming a without rods of open-web truss, in the upper and lower horizontal truss surface covered go bedplate, crane operation organization and electrical equipment installed in bridge internal, self-respect lighter, whole stiffness big in China is that more widespread adoption of a type. Ordinary bridge crane mainly adopts electric drive, it is to be in commonly driver indoor manipulation, also have long-distance bridge crane ,Control. Lifting weight can reach 500 tons, span of 60 meters. payments and plate steel composed of simple beam, with the hand type hoists or electric hoist match on simple car as lifting car, the car is in commonly strander beam under operation on the flange. Bridge along on a high orbits, also can along the suspensory on elevated the following orbits, this kind of crane beam cranes called suspension. Metallurgy special bridge crane in steel production process can participate in particular process operation, its basic structure and ordinary bridge crane is similar, but in lifting cars also has a special working organs or device. This kind of crane characteristics of the work is used frequently, conditions and job level is higher. Basically has five types.
Bridge crane safety check to ensure the safe operation of the bridge cranes, in crane operation period to some general safety inspections and inspection items and points as follows: (1) the hoisting height peneumatied device, travel limit switches and all the interlock device performance is bridge crane
Often, safe and reliable. (2) the main parts meet safety requirements: less than the original size increase openings less than 10%, 15% torsional deformation, Board hook bushing wear less than the original size, 50% of the board hook mandrels wear less than 5%, no spalling, burr, weld repairs. Hook rack and pulley without obvious flaw. Wire rope surface wire wear and corrosion is less than 40% of wire diameter, broken wires in a twined within less than the total silk from the number of 10%, no bufo, without obvious attenuate, without mandrel department of emergence, blind Angle twisting, extrusion, annealing, burning phenomenon. At the end of the wire rope connection and fixed clip next, clips, -200 block connect intact, without loosing, linking piece not less than 2, clip next amount not less than 3. S no crack, links, fixed without shake, A hollow wear less than 20% of the original wall thickness, Safety coil not less than 2 laps, drum and wire rope diameter ratio meets the requirement. Balance wheel fixed intact, the wire rope should comply with the requirements. Brake flawless, without loose, no serious wear and brake clearance sides equal size, have enough braking force, brake with less than 50% of the original thickness wear. Through the bridge crane safety routine inspection, to prevent accidents and reduce equipment accidents and improve equipment availability, reducing maintenance cost etc are plays a remarkable role.
Welding equipment and welding machinery roller
Welding equipment and welding machinery roller-welding is a manufacturing technology, it is to adapt to the needs of industrial development. modern industrial development as a basis for development, and direct services in the machinery manufacturing industry. Welding technology development and manufacturing industries closely linked to the needs of general industrial advanced countries, Steel output in general about the need for welding technology products can be formed, the laborers in the oil, mining metallurgy, metal structure, Lifting transport, surface transportation, aerospace, computer flu bridge construction machinery and equipment manufacturing sector, Welding has important and wide-ranging role. Many of the equipment of large-scale structure, almost all of welded structures.
Now with the development of science and technology, the scale of production growing, welded structure is moving in super high-capacity high parameters in the direction of development, which is not only the need for welding production of higher quality and better performance of the welder, welding material and welding technology, but also to provide the superior performance of the welding process equipment, welding production mechanization and automation, reducing anthropogenic factors, guarantee the quality and stability of welding, Welder improve working conditions, increase productivity purposes. However welding production is integrated production and welding pieces of the manufacturing process, a welding process itself there's also a lot of co-ordination processes, and therefore welding production mechanization and automation, not only confined to the welding process itself, including the welding process, the ministry convergence of various processes of mechanization and automation, Only by achieving the various processes of mechanization and automation of welding production can be achieved comprehensive mechanization and automation.
Welding machinery and equipment is divided into the following types : welding fixture, welding-machine and welding pieces of machinery and transport equipment other affiliation. From the use of scale, welding machinery and equipment is divided into two categories of general and special. General welding machinery and equipment strong common use of sexual Canton, the entire machinery products can adapt to changes in the structure of the repeated use. They can use combination can also mix in welding production line as a production welding components. Specialized welding machinery and equipment in order to meet but varieties, a large amount of specialized welding production needs of design and manufacturing. Such equipment specialized, high productivity, advanced control system, a good product mix to meet the welding process, Mass production requirements.
Welding machinery and equipment for the production of welding the beneficial effect of the following aspects :
1) using welding fixture. Parts are positioning device positioning, not crossed, we can not accurately measure the location of assembly, thereby ensuring the accuracy of assembly, accelerated the progress of the assembly work.
2) As in the welding fixture can be forced to give advance or reinforce anti-distortion, they are able to control or eliminate welding deformation.
3) using welding fixture, due to the welding assembly to ensure the accuracy and control of welding deformation, Therefore, to enhance the exchange of welding performance and welding pieces of the tie hole, groove with mechanical elements to be reduced from the first welding processing into first after the welding process, thus avoiding the large welded structure welding process on behalf of difficulties, to shorten the production cycle of welding.
4) using welding machine building can be shortened assembly and welding process, welding pieces of anti-change time reduce auxiliary working hours, increased utilization of welding and welding productivity.
5) using welding machinery spaces will welding pieces in the most favorable position welding. This is conducive to operate, enabling welding quality assurance, but also intensify the welding process norms, full welding performance.
6) Use of chanting positioner to expand the scope of the welding welder.
7) using welding machinery and equipment, will enable the manual modification of machinery and the only person in control of the position, factors that reduce the quality of the welding impact, but also lowers the level of manipulating welder requirements.
8) Only with mutual welding machinery and equipment to be matched in difficult conditions, environmental hazards, not directly manipulated by artificial occasions welding operations. For example, in the heat, Sham Shui Po, a radioactive environment for the conduct of welding operations, need with the corresponding welding machinery and equipment interfaces can be achieved.
9) To Make welding process itself mechanization and automation, or welding production process to achieve comprehensive automation, require welding machinery and equipment support can be achieved. In short, welding machinery and equipment for welding production process enabling role is multifaceted.
In a nutshell, is to ensure that the welding quality, and improve welding productivity, improve workers Zuye environment, mechanization and automation of welding production process four aspects. So in the welding shop or at the construction site. Welding machinery and equipment has become welding production process indispensable equipment, which was widely used. Welding is a roller-roller through the initiative and welding pieces of friction, lead welding pieces of rotating machinery modification. Welding roller stand for the main pieces of tube welding and welding assembly. If the right owners, the high roller follower appropriate adjustments will be able to conduct Cone, ranging from sub-diameter rotating assembly and welding. Some non-circular shape welding long pieces, if their card installed in a special card for the ring, Also available on the shelves of welding roller welded assembly work. Roller-welding to the structure and the breakdown is as follows : the first is the long axis of the wheel-F. Roller along with two parallel axes, and the driving device linked to a row to take the initiative wheel, another row of the roller follower. there are two rows of rollers are aware of, mainly for the slender-thin pieces of welding and welding of the group. Some long axis of its F - scroll wheel for a roller-long, has a diameter of 0.3-0.4m, a length of ~ 5m. Shell placed on the axial deformation not apply to thin, small-diameter, multi-cylinder welding pieces of the team up and girth welding. Some long axis of its F - scroll wheel for a long-roller, diameter and a length of ~ 5. Shell placed on deformation not apply to thin, small-diameter, multi-cylinder welding pieces of the team up and girth welding.
F-long axis of the wheel are based on users welding pieces of the characteristics of its own design and manufacture, market for the selected few stereotypes products. The second category is modular roller stand, its active wheel racks, roller-follower. Hybrid wheel frame (that is, in a stent with an initiative on the wheel and a roller follower Block) is an independent, using welding pieces under the weight and length of arbitrary composition, its composition ratio is not only a more than one combination.
Therefore, it is flexible, the applicability of welded pieces of a strong, which is the most widely used form of the structure. Domestic and foreign manufacturers have their own series of products supply market. If welding thickness and length of the smaller long welded pieces, it is appropriate several mixed-wheel combination, This direction along the length of the cylinder have the initiative wheel drive, welding pieces from slipping and distortions. If welding thickness larger, better rigid tube welding pieces, we would often take the initiative to use the wheel - and-roller follower of the portfolio, Even though the initiative is the roller-cylinder side-driven rotating welding pieces, but due to the welding pieces of rigid, and managed to maintain a uniform speed, not causing distortion. To diameter of the welding of different welding, the welding Roller roller-spacing should be able to adjust.
Adjust two ways : one is self-tuning; A non-self-tuning of. Self-tuning based on the diameter of the welding automatically adjust the wheel spacing; Non-self-tuning the mobile scaffold on the wheel on the Block, to adjust the wheel spacing. Non-self-tuning of the roller frame is welded mobile scaffold on the wheel on the Block, to adjust the wheel spacing. The heavy roller stand, and use the shop lifting equipment moved roller Block Sub-conditioning. Roller-right light, the use of manual and electric screw-nut body to Block Mobile scroll continuously. In order to facilitate adjustment wheel the distance between planes to accommodate different length welding pieces of welding assembly, Some roller shelves are also installed mobile or non-motorized travel agencies, along the migration path to adjust the distance between each other. Welding roller-use DC motor-driven, pressure-relief governor. But for the assembly work roller frame is used AC motor-driven, constant speed operation.
Recent years, with Crystal Gateway flow control inverter and improve the performance of lower prices, AC motor drive, VVVF welding roller frame is also increasing. MULTI-metal wheel with steel and ductile iron alloy production, the surface hardness of about 50 heat treatment HRC, roller diameter between 200-700mm. Foreign welding roller stand many varieties, than the entire series, facing an ~ 1500. apply welding pieces ~ 8m diameter of a standard modular roller frame (two active and two blocks roller follower rollers Block Portfolio) supply all series. Roller its multi-line speed in 6 ~ 90 m / h between non-adjustable level, there is some welding to prevent axial movement functions. China has many manufacturers to produce welding roller stand, the biggest loading capacity has reached 400 t, apply welding pieces of up to 6 m in diameter. Roller line speed over 60m in 6 ~ / h between variable speed. Preventing axial movement of the wheel-welding production already, but need to improve the quality of performance. 1997 China Statistical Yearbook welding, China has 23 auxiliary welding machine manufacturers of various types and specifications of welding roller stand, user needs, should first be selected. Selection, in addition to the wheel frame welding meet welding weight, tube diameter and welding speed requirements, should also enable the wheel-drive torque than welding pieces of
收藏