What is a scraper, it is important to know the workers in the construction and utilities. The machine is an earth moving vehicle. The main purpose is layer-by-layer cutting of soil, its transportation and shipment to appropriate storage locations. During operation, the unit compacts crumbling soil, which allows you to abandon highly specialized equipment.
Classification
The separation of the machines in question is performed according to several parameters:
- By bucket capacity in cubic meters. Modifications with a working body of more than 15 cubic meters are considered to be large-capacity equipment. m
- Type of download. Here, the functioning systems of the main element are involved. The first type includes machines of standard design, the second - scraper-drags, as well as rotor and elevator variations.
- Unloading. In this segment, free, forced and combined models are distinguished. In the first case, the procedure is carried out by releasing the bucket under its own weight. The second option involves pouring soil through the back wall, and in the third case, cleaning is performed with a combination of both of these methods.
- Type of drive. It can be hydraulic, cable or electromechanical. Hydraulics include a pump, a reservoir, connecting hoses and a distributor. In the cable version, work is carried out through a mechanical winch, special blocks and a system of polypastes. The operation of the electromechanical unit is based on the interaction of the engine, gears and gears.
- Trailers, semi-trailers, self-propelled and wheeled trains.
Device
You can understand what a scraper is after studying the design features of the machine. As a working body, a welded bucket acts, equipped along the edge of the bottom with step special knives. The back is equipped with a buffer that plays a two-digit role. The specified element is intended to stop the bulldozer part of the equipment or the movement of the tail of the rear wall in the desired direction. Side elements are made of steel sheets, which are reinforced with stiffeners.
In the sides of this unit there are several brackets and eyes. These components are used to fix the hydraulic cylinders and lever dampers. In addition, there is a supporting part for mounting the articulated harness and the rear wheel axle. The back of the tilt is an active shield with guide rollers. They are not designed specifically to hold the back wall during operation, but are focused on additional support. The main function in the indicated direction is performed by the shank and the hydraulic cylinder system.
The front frame of the machine is made according to the type of arch and is equipped with a kingpin that aggregates with a tractor, levers, an arch and a harness. On the cable version, the bucket is controlled somewhat differently. It is a single design with the rear of the equipment, consists of a pair of sidewalls and a bottom that smoothly transforms into a partition.
Principle of operation
The shovel of the scraper with forced unloading functions by turning the bottom with the rear walls around its axis. As a result, the load gets enough sleep under its own weight as a result of the action of the rear part of the device. The hydraulic mechanism that advanced models are equipped with makes it possible to empty the bucket completely, with virtually no residue.
Trailed analogues are equipped with an earring that acts as a hitch when connecting the base with a tractor or tractor. The design also includes a pivoting swivel mechanism, a supporting frame, a damper and a rear wall. Management is carried out through levers from the operator's cab. It should be noted that trailed modifications are relevant for operation in regions with variable terrain. Rope versions work through forced material unloading. Self-propelled vehicles of this category include a standard tractor with one axle and a special semi-trailer.
Features
Scrapers on wheels with pneumatic drives and semitrailer counterparts have pretty good speed performance. A machine with a uniaxial configuration can accelerate to 50-55 km / h, and with a double axis - up to 70 km / h. A special train of 2-3 units makes it possible to significantly increase the performance of units. An important element in improving performance is the use of a scraper conveyor, which is driven by an electric or hydraulic motor.
Functionality
Continuing to consider what a scraper is, it is necessary to pay attention to the high bucket loading parameter with a simultaneous decrease in traction, provided that the working body of the machine is filled by at least 25%. Automation of operation allows you to maintain the optimal mode of operation of the power plant, and also contributes to improved performance.
To improve the accuracy of work planning, in the case of servicing road excavations and embankments, the automated system “Stabiloplan” is used, which makes it possible to guarantee stabilization of the longitudinal movement of the angular position of the bucket, which is especially important during planning works.
Technological nuances
In order to properly organize the work of a scraper for cleaning soil or snow, they first draw up a diagram of the functioning of the machine. The unit’s performance is affected by the ability to use the maximum bucket capacity. As practice shows, a useful factor is best manifested if the filling of the dump is carried out at a speed of 3-4 km / h.
Moreover, the thickness of the cut sheet does not exceed 70-350 mm. The final parameter depends on the soil specification and the environmental conditions of the machine. If the equipment is equipped with a mechanism with a gradual deepening of the knife, the thickness of the cut and its width are automatically adjusted, depending on the power of the pusher and other subjective factors.
Exploitation
The specified method is well suited not only for land cultivation, but also for snow scrapers. Reduce the working time allows the step-by-step system of collecting bucket. For example, surface cutting is carried out by the method of ribbed staggering, using successive rows of penetrations that are identical in length and placement. In this case, the processing width in one pass is not more than 1300 millimeters, the second row is carried out at a distance of half the parameter of the first finish.
Such an approach makes it possible to increase the possibility of loading the blade by 12-15%, as well as reduce the time of soil, snow or sand set up. It is noteworthy that in this way this machine can work without a tractor tractor. On loose soils, a special treatment method known as pecking is used. In this embodiment, the bucket is buried twice as much, and the engine runs at a steady load. As a result, the vehicle runs intermittently until the blade is full.
Schematic image
The diagram below shows the general design, which makes it possible to understand what a scraper is.
- Bonnet part.
- Rope management.
- Cargo hold
- Hydraulic traction.
- Work knife.
- Bottom.
- The connecting mechanism.
- Cuff.
- Wheel drive.
- The connecting mechanism.
- Device for starting the working unit.
- Additional hydraulic equipment.
As you can see, everything is quite simple.