Introduction of various mobile cranes
1, truck crane truck crane: Truck cranes English name Truck Crane, the country with QY said that if QY20 / 20t truck crane (truck crane). The crane mounted on a general or special vehicle chassis chassis performance is equivalent to the total weight of the vehicle the same truck, meet the technical requirements of road vehicles, which can be used freely on all types of roads. Such cranes are generally available on both cab off, you must extend the legs when the job is stable. From the weight of a large range available from 8 tons to 1,000 tons, the number of axles chassis, from 2 to 10. Is the largest output, the most widely used type of crane.
2 tire tire crane crane (RTG) Rough Terrain Crane, no domestic tire cranes (RTG). Lifting portion is mounted in a special pneumatic tire crane chassis. Combined with an engine on and off, driving speed of not more than 30KM / H, the vehicle width is wider, and therefore should not be long-distance driving on the highway. Has no legs hoists and hoist driving functions for moving away from garages, docks, construction sites and other places of limited hoist operations. Because without legs hoists and hoist travel often some accidents, major domestic companies have gradually lifting hoist travel cancellation feature. The main features of the tire cranes are: its driving cab and crane cab combined, are evolved by crawler cranes (crawler) will be tracked and walking stents have become part of the running gear tire chassis, overcome the crawler crane (crawler) shortcomings track shoe on the road damage, driving speeds are more cranes (crawler) fast; job stability, lifting capacity, can hoist walking within a specific range, but must ensure smooth road solid tire pressure to meet the requirements, suspended above the ground shall not exceed 50CM; ban with a load of walking long distances. To ensure operational safety, do not fight the current domestic basically prohibit legs were lifting operations.
3, a crane rough terrain cranes developed in the 1970s, its function and tire crane hoist similar, and we can not have legs hoists and hoist travel. The difference is to improve the form and structure of the chassis by a unique chassis structure brought running performance. This crane engines are mounted on the chassis, the chassis has two axle off-road tire tread and four large diameter. The four wheels are wheels and steering wheels, when the transfer station on uneven muddy site, all four wheels to transmit power, that four-wheel drive to improve capabilities through the muddy ground and uneven pavement. When a flat road at a faster speed, with only two wheels driving front axle or rear axle, to reduce power consumption. Crane random file, indicated with 4 × 4-wheel drive, 4 × 2 shows four axles have two wheels are drive wheels. The models suitable for small venue operations. Can realize continuous variable speed, in the case of road resistance mutations do not turn off the engine, thus greatly facilitates the driver's operation. The rough terrain cranes can be a performance of extended, powerful and flexible tire crane.
4, all-terrain type, also known as all-terrain cranes, truck cranes and a rough-terrain cranes both the characteristics of high-performance products. It can shift as quickly as truck cranes, long-distance travel, but also to meet the requirements of the narrow and bumpy or muddy job site, that travel speed, multi-axle drive, all-wheel steering, steering three ways, from the ground gap, high climbing capacity, crab walk, is a very promising product. But the price is higher, the higher the level of use and maintenance requirements.
5, crawler cranes crawler cranes (crawler) Crawler Crane, general domestic use QUY representation. But Trinity crane with international standards for use in English naming its crawler code for SCC (SANY Crawler Crane head of the English alphabet). The main features of crawler cranes are: its driving cab and crane cab combined, ground area, the average pressure on the ground is small, good stability, in soft, muddy ground operations; traction coefficient, climb slope, can travel on bumpy grounds; but crawler running slow, and the process of moving the road to be damaged, requiring shipment by flatbed trailer, poor mobility when job transitions.
6, special crane to accomplish a specific task and the development of special cranes. For example: the tactical and technical support for the implementation of mechanized units used, mounted on off-road vehicles or armored rescue vehicle lifting wheel; to deal with road traffic accident wrecker, etc., fall into this category.
Job type cranes: refers Cranes busy degree and extent of changes in the load parameters.
How busy working on the crane, it refers to the total time in a year, than the actual total number of operating hours when the crane; for institutions, it means that when an institution run several times in a year when the ratio of the total number. Crane in a work cycle, the percentage share of agency operating time, called the duty cycle of the institution, expressed by JC.
The degree of load change, according to the rated lifting capacity of the crane design in actual operation, the crane lifting loads tend to be less than the rated load. K represents the degree of change in use from the weight of the load utilization factor. k = the year from the weight of the crane from the weight of the average of the actual / crane rated.
According busy work load degree and extent of changes in the crane, the crane is usually the type of work is divided into: light, intermediate, heavy duty, and Extra Heavy four kinds of levels.
The type of work the crane and lifting weight are two different concepts, lifting capacity, is not necessarily a weight class, from the small weight, not necessarily light level. Such as hydropower capacity of the crane with hundreds of tons, but the opportunity to use it rarely, and only in the installation of the unit, only use the repair crew, and the rest of the time stop there, so even though from a great weight, but still belong to the light level . Another example is the use of the station yard cranes, although from the weight of small, but very busy, are heavy duty type.
The type of work and safety performance crane has a very close relationship. Starting weight, span, crane lift height the same, if a different type of work, in the design and manufacture, the safety factor is not taken the same, that is, parts of models, sizes, specifications vary. Such as rope, brake due to the different types of work, different safety factors (light-level security coefficient is small, heavy duty safety factor), the selected model is not the same. Then as a 10t overhead crane, for intermediate type of work (JC = 25%) of the lifting motor power N = 16KW, and for heavy duty type (JC = 40%) compared with the hoisting motor power N = 23.5 KW.
From the above we can see the type of work if the light level of the crane used in heavy duty type of place, a crane will often fail, affecting safety in production. Therefore, security checks, pay attention to the type of work the crane must be consistent with the working conditions.
Crane characteristics: the carrying capacity of the crane structure, boom lifting capacity and machine stability against overturning the envelope of the three curves.