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 Sweeper 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 Qingdao Sweeper 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.

If the hydraulic system is compared to the human body, then the hydraulic oil is equal to human blood. In the hydraulic system, the hydraulic oil plays a role in energy transmission, system lubrication, and prevention Qingdao Sweeper cycloidal hydraulic motor The functions of corrosion, rust prevention and cooling, and whether the hydraulic system can work effectively are closely related to the type and selection of hydraulic oil. Coding, composition and characteristics of hydraulic system: high purity general machine tool oil, refined mineral lubricating oil, with good rust resistance and oxidation resistance. High wear resistant hydraulic oil, refined mineral lubricating oil, rust proof, anti-oxidation, anti-wear. High temperature and high pressure hydraulic oil, with the characteristics of rust prevention, oxidation resistance, wear resistance, etc., is refined into mining lubricating oil, and added with viscosifier. Refined mining lubricating oil HG hydraulic guide oil, rust proof, anti-oxidation, anti-wear, anti stick slip. HS synthesis special-purpose Sweeper cycloidal hydraulic motor Hydrocarbon is a kind of low temperature hydraulic oil, which has the characteristics of anti-oxidation and anti-wear.

At present, the system used in series by multiple cycloidal motors (see Figure 1) is applied to sweepers, trenchless drills and airport luggage carts. The output shaft of the hydraulic motor often leaks oil during use, so it is useless to replace the dynamic seal of the output shaft. In series application, the problem of casing oil leakage pressure is ignored. The oil leakage pressure of the housing refers to the maximum pressure that the motor shaft seal can bear after the hydraulic motor is fully lubricated inside; If the hydraulic motor is applied special-purpose Sweeper cycloidal hydraulic motor Improper. After the machine has been working continuously for a period of time, due to various factors, the oil in the housing will not be released, resulting in higher and higher pressure in the housing of the hydraulic motor, which first leads to the failure of the shaft seal. The casing leakage pressure mentioned here is not the bursting pressure of the casing, but the pressure that the motor output shaft dynamic seal can bear. In the motor samples of some manufacturers, only the back pressure is mentioned. Actually, back pressure refers to electricity Sweeper cycloidal hydraulic motor manufactor The return oil pressure of the engine, not the oil discharge pressure of the casing. During operation, the requirements for the oil discharge pressure of the cycloidal motor housing are as follows. Eaton is the world's first cycloid motor manufacturer. In China's domestic cycloidal motor manufacturing industry, Jining Jinjia Hydraulic Co., Ltd. uses Eaton technology to produce cycloidal motors. Its output shaft dynamic seal has better bearing capacity, that is, the unique internal oil circuit design of the company's products enables internal oil drainage not only to lubricate parts, but also to discharge excess oil while maintaining a certain housing oil drainage pressure.

The oil distribution sleeve is synchronized with the rotor, so that the rotor rotates once, and the seven oil distribution holes on the housing are closed 840 times by the twelve diaphragms of the oil distribution sleeve, while the rotor and stator form the largest and smallest closed cavities respectively 1420 times, collectively referred to as the seal cavity. In the circle of the oil distribution hole of the closed housing, the oil inlet and outlet of the rotor have three chambers respectively, one Qingdao Sweeper cycloidal hydraulic motor The cavity is closed. When the rotor is transferred from the smallest enclosed cavity to the next largest enclosed cavity, before the rotor is transferred from the largest enclosed cavity to the next smallest enclosed cavity, oil is supplied to four cavities and three cavities special-purpose Sweeper cycloidal hydraulic motor Drain the oil.

When the working load changes from low speed to high speed in a wide range, the hydraulic motor is also required to be able to drive and regulate speed in the corresponding wide range, which requires the motor to have good low-speed stability and high speed performance. The speed regulation range K of the hydraulic motor is usually expressed by the ratio of the allowable maximum speed to the minimum speed. special-purpose Sweeper cycloidal hydraulic motor It is the highest operating speed of hydraulic motor, but it is limited by many factors, mainly including: 1. Service life. After the speed increases, each pair is worn Qingdao manufactor The service life is shortened. 2、 Mechanical efficiency limits. At high speed, the hydraulic motor needs to input large flow, accordingly, the hydraulic loss of each circulating component increases, reducing the mechanical efficiency.

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 Sweeper 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 Sweeper cycloidal hydraulic motor manufactor 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).