Application method of automatic leveling device for asphalt concrete paver (1)      

This paper mainly discusses the use of asphalt paver automatic leveling device.

First, the choice of sensitivity

Sensitivity means that the controller does not issue the range of the adjustment signal. The general vertical and horizontal controllers have the lowest sensitivity of 10 gears and 1 gears, and the 10 gear has the highest sensitivity. Through the rotation sensitivity regulator, the control of each gear shift is realized. Different sensitivity gears should be chosen according to different working conditions during construction.

(1) the lower sensitivity of the pavement: because the smoothness of base is poor, if the controller sensitivity is too high, the deviation of signal detection is too sensitive, too often follow the lateral controller, but the impact of pavement roughness, so it should not be too high. The sensitivity of each block of the longitudinal controller is shown in table 1.

Table 1

Gear              1  2     3    4    5     6     7    8910

The values are 65.4, 4.8, 4.2, 2.4, 1.8, 3.63, 1.2, 0.6

Generally choose 5, 6 gear is more appropriate. At this point, when the deviation is greater than 3.6mm, the longitudinal controller sends the adjustment signal.

The sensitivity of each position of the lateral controller is shown in table 2.

Table 2

Gear 12345678910

The values are 0.2, 0.18, 0.16, 0.14, 0.12, 0.08, 0.06, 0.04, 0.1, 0.02

The choice of the sensitivity of the lateral controller is influenced by the paving width. Paving 3M wide road, choose 5-6 block, when the transverse slope exceeds the setting cross slope of 0.10%, or the control thickness exceeds the set thickness of 3.6%, the controller sends out the adjustment signal; paving 4.5m wide road, using 7~8 block. When the cross slope exceeds the set cross slope of 0.10% or the controlled thickness exceeds the setting thickness of 3.6%, the controller sends out the adjustment signal. The wider the paved road, the higher the sensitivity of the choice.

(2) the selection of surface sensitivity: in the "highway engineering quality inspection and evaluation standard", the smoothness requirement of asphalt concrete surface layer is stipulated as "+ 3mm/3m". Therefore, the longitudinal controller sensitivity should choose 7~8 block, in the use of large paving width should choose 8 blocks.

Two. The position and direction of the controller

The position of the controller has a great influence on the effect of automatic leveling. If the controller is set on the trailing edge of the screed, it will move up and down with the change of the elevation of the ironing plate, of course, the thickness deviation can not be detected and adjusted. If the controller is set near the trailing point of the traction arm, a slight change in the elevation of the screed will cause a large amount of up and down movement at the controller, resulting in excessive adjustment and unnecessary regulation.

The automatic leveling device takes into account the influence of paver space, usually the transverse controller is fixed on the top of the screw in front of the screed, and some paver is located in front of the vertical table. This setting is due to the fact that the lateral controller is very sensitive to deviation and reduces sensitivity when used. The longitudinal controller can be adjusted, and the support arm of the longitudinal controller can rotate 180 degrees before and after the sleeve in the side of the ironing plate, and the length of the support arm can be adjusted within the range of 2m. Therefore, the longitudinal controller should be noted that it must not be installed behind the ironing board, must be placed in front of the ironing board, and the distance from the ironing plate to draw the front hinge point to the edge of the screed 1/3 is appropriate. The front of the vertical and horizontal controllers must be opposite to the direction of the paver.