How to use screed plate reasonably?
The adjustment of paver paving thickness is achieved by changing the elevation angle of ironing board, and the elevation angle should be kept unchanged during paving operation. The increase of elevation angle will increase the thickness of paving layer, and vice versa. Adjust the elevation angle, the screed adjustment bolt to make the ironing board around the hinge point on the arm turning an angle to change the screed and the bottom surface of the horizontal plane angle; but also by adjusting the arm traction height to change the screed and the bottom surface of the horizontal plane angle.
1. preparation work before paving
(1) preheating and insulation of ironing board;
Before operation, preheat the ironing plate by 20 ~ 40min to make it close to the temperature of the mixture.
In order to prevent the ironing cooling, the preheating system should be used for thermal insulation in order to stop the operation.
When heating the iron plate with gas, attention should be paid to controlling the heat to prevent the ironing board from overheating locally. When heating, the method of intermittent combustion and multiple heating shall be adopted, and ignition, combustion and flameout, hot air alternating heating can also be adopted. Each ignition time shall not exceed 10min.
When preheating, observe the burning situation. If the flame is extinguished, the gas switch should be turned off immediately to find out the cause, and the fuel gas can be re ignited before the gas is discharged.
(2) preparation and adjustment work;
Including: paving thickness and screed width adjustment; screed camber adjustment; paving thickness determination and screed elevation adjustment of the initial work; to determine the number of speed selection and feeding car matching; automatic leveling device for reference.
2. camber and elevation should be adjusted in time
The adjusting mechanism of ironing plate arch is divided into two kinds: hydraulic type and mechanical type. Mechanical ironing plate can be adjusted by the central screw adjusting device, hydraulic type through the operation button on the control panel to adjust the screed two center arch of the hydraulic cylinder, and then another single brake cylinder position can be fixed. Generally, the absolute value of the arch (mm) or the percentage of the cross slope gradient can be read directly on the ruler, and after adjusting the camber, the calibration should be carried out and adjusted again if necessary.
The initial working elevation of the screed depends on the thickness of the layer, the type of mixture and the temperature. The elevation is usually 20 degrees to 40 degrees. When the paving thickness is large, the initial elevation angle should be slightly larger.
3. install extended section correctly
Screed early bolted extension, new screed is hydraulic connection through a hydraulic hose connection on the rear wall to install the extension screed on the tensioning cylinders (see Figure 2) input 20 MPa oil pressure after tensioning cylinder piston rod.
In addition, after the suspension of work, deal with the preheating screed, because the mixture at high temperature with 30 DEG C screed bottom will be sticking to the bottom plate, the adhesion of particles with screed dragging forward, will make the formation of grooves and paved surface crack. The heated iron plate can press the ironing layer so as to make the road surface neat and traceless. But heating the ironing plate can not overheat, overheating, in addition to easy to ironing plate itself deformation and accelerated wear, but also make the surface layer of asphalt mortar and pull groove. During continuous paving, the heating is suspended when the screed is fully heated. When paving low temperature mixture and asphalt glue sand, heating plate should be continuously heated at lower temperature.
4. the reasonable maintenance of ironing board
During the use of the screed, the composite calcium based high temperature grease should be regularly added to the ram, vibrator and other parts. The process is accomplished by lubricating the sequential distributor. Wherein, the mechanical lengthened ironing plate controls 64 lubricating points respectively through 8 sequential distributors, and the hydraulic telescopic ironing plate controls 60 lubricating points respectively through 8 sequential distributors. When the lubrication of a point is completed, the sequential distributor will lubricate the other point through the next line to ensure that the lubricating points are equally lubricated.
You should also check the electronic heating equipment of the cable and hose is damaged and leaking every time before starting to work, it is necessary to change; every time after construction shall promptly remove the asphalt mixture with kerosene residues on the ironing plate; when cleaning the screed for high pressure cleaning, not directly to the water of bearing and electrical components, after cleaning to add to all bearing grease.
