Common faults and solutions of vibratory rollers

The vibration of the vibratory roller relies on the rotation of an exciting rotor that loses its static balance when the hydraulic motor rotates, so that the front wheel vibrates to enhance the compaction capacity and affect the depth.

1. Electrical system

Common faults: Under normal circumstances, the poor quality of the vibrating switch itself or the improper operating force will cause the vibrating switch to have poor contact.

Solution: If the vibrating wheel does not vibrate, first check the vibrating switch to see if the vibrating switch is intact and whether there is a phenomenon of poor contact. If it exists, it should be repaired or replaced. Secondly, check whether the electrical circuit is damaged, the protection team is burned out, the circuit is short-circuited, and the circuit is disconnected (focus on checking the vibration switch to the vibration pump control solenoid valve circuit), and eliminate them one by one.

2. Hydraulic system

Common fault: When the hydraulic oil of the hydraulic system does not meet the requirements of pressure and flow, the oil supply of the vibration system is insufficient, and the vibration motor will not rotate or the speed is quite low. The reasons for insufficient fuel supply mainly include the following aspects:

(1)The speed of the diesel engine is too low, and the flow and pressure of the hydraulic pump cannot reach the set value. Check whether the throttle control lever is in the correct position, and ask professionals to overhaul the diesel engine and restore the normal speed of the diesel engine;

(2)The hydraulic pump and the hydraulic motor are severely worn and the oil leaks inside. The main influencing factors are: early wear caused by non-compliance with the requirements of hydraulic parts dimensional accuracy, manufacturing technology and material selection. Impurities such as mechanical wear in the system cause early wear of the plunger and plunger hole, sliding shoes and swash plate. At this time, the extracorporeal circulation device can be used to queue up mechanical wear and impurities in the hydraulic system to eliminate early wear; improper use. Maintenance personnel often forget to add oil to the casing after overhauling the pump or motor. In the absence of lubricating oil, operation will cause severe wear of the pump and motor in a short period of time, resulting in internal leakage. The majority of maintenance personnel pay attention to refueling the shell to avoid unnecessary losses. Valves, joints and other hydraulic accessories are malfunctioning. The main manifestations are: damage or blockage of the vibration switch valve: damage to the vibration switch valve, resulting in no deflection of the swash plate, and vibration pump The displacement is zero, there is no flow output, the motor does not rotate or vibrate without pressure oil; the pressure cut-off valve is damaged: the pressure cut-off valve opens too early to release the pressure of the swash plate control circuit, and the swash plate returns to the zero position. The system pressure does not meet the requirements, the hydraulic oil pressure of the vibration system is too low, the vibration motor does not rotate or the rotation speed is too low; the overflow valve is damaged: the overflow valve opens too early to relieve the pressure, and the system pressure does not reach the set value, the vibration system Because the oil pressure is too high, the vibrating motor does not rotate too slowly; the O-ring at the joint is damaged, resulting in a loose seal; due to the vibration, the mutual friction is damaged; the quick-change joint is not screwed in place, and the oil cannot be conducted.

Solution: If the hydraulic component fails, please ask a professional to repair it. If necessary, replace the damaged part to ensure the normal operation of the equipment. If the hydraulic oil filter has a low filter accuracy level or the filter is damaged, other impurities such as mechanical wear in the oil cannot be effectively filtered, resulting in no blockage or early wear of other hydraulic parts, the hydraulic system should be cleaned and replaced with a clean hydraulic Oil and high precision filter.

3. Vibrating wheel

Common failures: most of the vibration system failures occur in the mechanical part, and the vibrating wheel is the main failure location. The coupling connecting the vibration motor and the eccentric device is damaged.

First of all, the spline shaft connecting the vibration motor and the coupling is broken. This is very rare. It usually appears on new machines. It is mainly due to the severe deviation of the coaxiality and verticality of the vibrating wheel components, or due to vibration. The fixing bolts of the wheel components can be broken and loosened, and the connecting part of the motor and the eccentric device is broken when rotating at a high speed under the condition of a large load.

Secondly, the nylon sleeve is severely worn, and the nylon sleeve of the coupling has quality problems such as material, strength or severely poor coaxiality of the eccentric device, which leads to early damage to the nylon sleeve, causing the system to have no vibration, weak vibration or occasional vibration. The lubrication, heat dissipation and clearance of the vibrating bearing directly affect the service life of the bearing. If the bearing is poorly lubricated, it will be severely worn in a very short time. The maximum allowable speed of a rolling bearing is usually determined by the allowable working temperature. For example, the working temperature of the vibrating bearing of the YZ18 series roller is generally 90℃-105 (ordinary high-speed heavy duty). The heat treatment process of the load bearing can ensure the dimensional stability below 150℃), the unique and effective bearing lubrication cold dynamic structure will greatly extend the life of the vibrating bearing; the clearance before the high-speed rotation of the bearing must be greater than the working clearance, and it needs to be more Large radial clearance. The early damage of the vibrating bearing is largely due to the quality problems of the vibrating bearing itself: the wear resistance, hardness, dimensional accuracy and heat treatment process of the bearing do not meet the requirements, and the bearing ring is burned; or the assembly is not in accordance with the regulations. When the bearing is damaged and the lubricating oil does not meet the requirements, the bearing is damaged early; or because the axial clearance is too small, the bearing rotates at high speed and generates heat to reduce the axial clearance and wear the cage.

Secondly, the specification of the selected bearing is incorrect. Compared with ordinary high-speed and heavy-duty bearings, vibrating bearings have higher requirements for performance parameters. The radial clearance of the bearing is larger than that of ordinary heavy-duty bearings. If you choose non-host manufacturers rashly And the approved bearing brands and specifications will cause vibration failure. If the bearing clearance is too small, after working for a period of time, the bearing heats up, which reduces the radial clearance, causing wear between the inner and outer rings of the bearing and the rollers, and the bearing is stuck. Vibration occurs, and the vibration will disappear again after a period of time. But because the bearing wears will be accompanied by a slight noise. If this is the case for a long time, the noise of the vibrating wheel will increase, accompanied by a whistling sound, and finally the vibration disappears completely, the bearing is completely burned to death, and the matching parts will also be completely damaged. . If the bearing clearance is too large and the axial and radial fit is not accurate, the bearing will also experience early wear and shorten its service life. Therefore, when choosing key accessories such as vibrating bearings, users must use the brands and specifications provided by the manufacturer or recognized by the after-sales personnel. Small losses in the name will cause serious consequences and cause unnecessary economic losses.

Solution: Most of the vibratory rollers currently in use are dual-frequency, dual-amplitude and adjustable. The amplitude modulation device consists of two left and right sides. For example, the 18t series vibratory roller, which is mainly used to compact roadbeds, relies on the forward and reverse rotation of the eccentric device to achieve different amplitudes. . If the vibration wheel amplitude modulation device is damaged, there will be a big impact sound during vibrating operation (when an amplitude modulation device is damaged, the impact sound is not very obvious), and a clear and coherent sound will be heard during the start or stop of the vibration Impact sound, the amplitude of vibration is chaotic, the amplitude is sometimes absent, sometimes large and sometimes small. When the amplitude modulation device fails, the damaged parts should be more abstracted in time.