Precautions for the Use of WTU75 / RP751 Pavers

Since its successful development, the WTU75 paver has undergone multiple improvements from WTU75 to WTU75A, WTU75D, and RP751 models. With its applicable performance and low price, it has won the favor of a large number of users. Its sales volume has reached over 500 units, making it one of the best-selling models among domestic pavers, with users all over the country.

In the course of contact with a large number of users, it was found that there are some problems in the use of this paver. The following explanations are made here.

1. It is essential to pay close attention to the maintenance of the machine

The maintenance of machines mainly involves lubrication, including timely addition and replacement of engine oil, grease, gear oil and hydraulic oil, etc.

The diesel engines used in the WTU75 / RP751 pavers are of two types: Deutz BF4M1013 and Shanghai Diesel D6114. If the engine oil is not changed in time or substandard engine oil is used, it may cause the D6114 type to burn oil. In addition, timely cleaning or replacement of the air filter element, idling the machine for 3 to 5 minutes when starting and stopping, and using qualified diesel are all necessary measures to prevent the machine from burning oil.

Automatic lubrication is adopted at the key lubrication points of the WTU75 / RP751 type paver for material conveying and distribution. Automatic lubrication pumps and progressive distributors have relatively high requirements for grease (lubricating grease). The viscosity of the common No. 3 grease on the market is high, which makes it somewhat difficult for the pump to self-draw grease. Therefore, when the temperature is below 20℃, No. 2 grease should be used.

Inside the automatic lubrication pump and the progressive distributor, there are plunger pairs. The fit of the plunger pairs themselves is very precise, so the cleanliness of the grease is also required to be very high. There must be no solid impurities in the oil; otherwise, it will cause faults such as wear of the lubrication pump plunger pair, jamming of the check valve, bending of the plunger, motor burnout and distributor jamming.

If the spare grease nipple of the automatic lubrication point leaks oil, a grease nipple with good reverse sealing performance should be found and replaced.

High-temperature grease is only necessary when laying asphalt materials.

2 Lubrication of the scraper feeding chain

The scraper feeding chain comes into contact with the material and works in a harsh environment. If it is not lubricated, it will lead to rust, material adhesion and chipping, accelerated wear of the feeding chain and the base plate, and even material jamming and chain breakage.

For the lubrication of the scraper conveyor chain, it is recommended to use a mixture of various waste lubricating oils and diesel, as diesel has strong permeability and is conducive to entering the interior of the chain. Before lubrication, the material transfer and distribution switch should be opened first to clean the material in the gap. Then, the cover plate in front of the hopper should be lifted and the mixed oil should be poured onto the chain. Lubricate once every 1 to 3 days. Lubrication should be carried out after the construction is completed.

3 The use of automatic leveling instruments and material level sensors

The automatic leveling instrument and the material level sensor should be connected in a power-off state. During the period of waiting for materials, the diesel engine can be turned off, but the entire machine must not be powered off; otherwise, it is easy to cause changes in the cross slope.

The guy wire should not exceed 40 cm, and there should be a distance of 30 to 50 cm between it and the road surface to be paved.

The ultrasonic material level sensor should be aimed at the position in the material distribution trough that is most sensitive to the material distribution speed and the forward speed of the paver, which is generally in the middle of the openings at both ends of the material distribution trough. Only in this way can the material transportation and distribution be carried out smoothly and continuously, thereby ensuring the flatness and density of the laid layer.

The height adjustment range of the material level sensor is quite large, but once its position is fixed, the adjustment range is often very small. Therefore, after adjustment, it generally does not need to be moved again.

4 Adjustment of the material gate height and control of the material level

The WTU75 / RP751 model is a mid-range paver, featuring a feeding method of synchronous material conveying and distribution combined with material gates. When paving roads of different thicknesses and widths, the adjustment of the height of the material gate is very important. The purpose of adjusting the height of the material door is to make the material level in the material separation trough basically consistent. Build expressways

The most common paving thickness for highways is 24 to 26 cm, and the width is 6.0 to 6.5 meters. At this time, the material door baffle is generally exposed by 3 to 6 cm. The road surface often has a certain slope. It is easier to distribute materials downward than upward. Therefore, the heights of the left and right material gates are generally not the same. The upward material gate should be lower and the speed of material distribution should also be higher (automatically).