The output pressure of the hydraulic motor also depends on the load. Rated pressure Pn: the rated pressure refers to the working pressure that the hydraulic motor can withstand during continuous operation. It can special-purpose Low speed cycloidal hydraulic motor To ensure the volumetric efficiency and service life of the hydraulic motor. Working pressure P: the working pressure is the actual pressure of oil input when the hydraulic motor is working Low speed cycloidal hydraulic motor Price power. Its value depends on the size of the load. However, the maximum working pressure is determined by the safety valve in the hydraulic system. The throttle adjustment value must not exceed the maximum pressure value of the hydraulic motor. The third is the maximum pressure: the limit pressure that the motor is allowed to overload in a short time. Pn ≤ Pmax value.
After disassembling and inspecting the hydraulic motor installed on the drill, it was found that the friction surface of the valve disc and the port plate of the hydraulic motor was severely worn, and the deepest worn part was 0. 15mm; The output shaft oil seal is leaking. Cause analysis of oil leakage of output shaft oil seal. After disassembly inspection and test, the axial and radial clearances of the output shaft meet the standard requirements special-purpose Low speed cycloidal hydraulic motor There is no obvious wear on the oil seal mating surface. However, it is found that the oil seal rubber has hardened and its elasticity has deteriorated. With the increase of sealing lip wear, the pre tightening capacity and sealing performance decrease, and the excessive oil temperature accelerates the wear of sealing lip; In addition, due to the liquid Wuhu Low speed cycloidal hydraulic motor The leakage of the pressure motor causes the back pressure in the housing to be too high, which further aggravates the wear and leakage of the sealing lip. The smaller the friction of the rotor in the stator sleeve, the higher the mechanical efficiency of the motor.
The hydraulic motor has two circuits: the hydraulic motor series circuit and the hydraulic motor braking circuit. These two circuits can be classified into the next category. One of the series circuits of hydraulic motors: three hydraulic motors are connected in series with each other, and a reversing valve is used to control the start stop and steering. The flow through the three motors is basically the same. When the displacement is the same, the speed of each motor is basically the same. The oil supply pressure of the hydraulic pump Wuhu Price High, small pump flow, generally used for light load and high speed. Serial circuit II of hydraulic motor: each reversing valve in this circuit controls one motor, each motor can work independently or simultaneously, and the rotation direction of each motor is also special-purpose Low speed cycloidal hydraulic motor optional. The oil supply pressure of the hydraulic pump is the sum of the working pressure difference of each motor, which is applicable to the condition of high speed and small torque.
Along the revolution direction of the rotor, the volume of the tooth cavity at the front side of the connection between the rotor and the stator becomes smaller, which is an oil discharge cavity, and the volume at the rear side becomes larger. When the connecting line passes through the two tooth roots of the rotor, the oil inlet ends and the largest tooth cavity appears. When the connecting line passes through the two tooth tops of the rotor, the oil drainage ends and the smallest tooth cavity appears. In order to ensure the continuous rotation of the rotor, it is necessary to have the same regular oil distribution mechanism to cooperate with it, so that the tooth cavity at the front side of the connecting pipeline is always connected with the oil drain port, and the rear side is connected with the oil inlet port. As mentioned above, the oil distribution mechanism consists of a housing and an oil distribution sleeve. The 12 longitudinal grooves (x) on the oil distribution sleeve and the 12 intervals formed by the oil distribution groove face the root and top of the rotor through the positioning device, which proves that when the largest and smallest cavities occur, the oil distribution hole of the housing can be closed, thus separating the oil inlet groove and oil outlet groove of the oil distribution sleeve.
The radial piston hydraulic motor uses a cam ring with a special curve to make each plunger reciprocate several times within one cycle of cylinder block rotation, which is called multi action special-purpose Low speed cycloidal hydraulic motor Internal curve radial plunger hydraulic motor (referred to as internal curve motor) is used. The internal curve motor has the advantages of small size, light weight, radial force balance, small torque ripple, high starting efficiency, stable operation at very low speed, etc. It has been widely used Low speed cycloidal hydraulic motor Price In marine machinery. Working principle of inner curve motor: the inner wall of the cam ring (housing) is composed of x evenly distributed curved surfaces with the same shape. Each curved surface with the same shape can be divided into two symmetrical sides. The side that allows the plunger set to extend outward is the working section (oil inlet section), and the opposite side is called the oil return section. The number of reciprocating times of each plunger per revolution of the hydraulic motor is equal to the number of curved surfaces of the cam ring x (x is called the number of times of action of the motor).
The valve control system controls the flow by changing the opening of the valve throttle, thus controlling the speed of the actuator. Usually, the reason for low efficiency is the existence of throttling and overflow losses. Almost all mechanical equipment adopts valve control system. The pump control system can realize the stepless control of speed by changing the displacement of variable displacement pump, or control the flow through the combination of multiple constant displacement pumps to achieve the stepwise control of speed. The reason for high efficiency is that there is no throttling or overflow loss. It is widely used in high power hydraulic devices such as pressure processing machinery and plastic machinery. The actuator control system controls the flow by changing the variable hydraulic motor flow of the actuator, or through the joint work of multiple quantitative hydraulic motors, or by changing the action area of the composite hydraulic cylinder. Similar to the pump control system, this system has high efficiency because it has no throttling and overflow losses. It is suitable for traveling machinery, press and other hydraulic equipment.