The hydraulic cylinder is an important part of the hydraulic cone crusher. In the working process of the crusher, due to improper selection of sealing elements and unreasonable sealing structure design, the sealing ring fails, causing internal and external leakage, which seriously affects the stability of the crusher. Performance, reliability and service life. Hydraulic cylinder leakage is generally generated after a period of use, and is divided into internal leakage and external leakage. The reasons for the leakage are detailed in the analysis below.
    The external leakage of the hydraulic cylinder can be directly found from the appearance. It is a common operating failure and an important factor affecting safety and environmental pollution. The internal leakage cannot be directly observed and it is difficult to make accurate judgments. 1. Reasons for leakage outside the hydraulic cylinder
    1. Oil leakage between cylinder tube and guide sleeve: static seal between cylinder tube and guide sleeve. Poor quality of the sealing ring, insufficient preload, scratched damage or distortion, and rough machining of the mating surface of the cylinder barrel and the guide sleeve can cause oil leakage between the cylinder barrel and the outer seal of the guide sleeve.
    2. Oil leakage at the matching point of the piston rod and cylinder head: the cylinder block, cylinder head, piston rod and piston are poorly processed and assembled, or the piston rod is bent and deformed. When the hydraulic cylinder is working, the axis of the piston rod and the cylinder block is inclined to seal the cylinder head. The unilateral deformation of the ring causes oil leakage at the fitting position of the piston rod and the cylinder head.
    3. Oil leakage between the contact surface between the piston rod and the guide sleeve: the oil leakage between the relative movement surface of the piston rod and the guide sleeve is *ly caused by the damage of the sealing ring installed on the guide sleeve and the strain on the surface of the piston rod. .
    4. Oil leakage between the cylinder block and the cylinder head: The material of the sealing ring at the cylinder head is too hard, aging, damaged or reused. Damage to the seal or improper installation during maintenance will cause oil leakage.
    5. Oil leakage caused by defects in various parts of the hydraulic cylinder: due to manufacturing defects in the cylinder block and cylinder head, or casting defects such as sand holes, pores or shrinkage in the guide sleeve, under the pressure of the hydraulic system, the defects gradually expand and cause oil leakage .
Second, the cause of leakage in the hydraulic cylinder
    1. Internal leakage between the piston and the cylinder wall: the seal between the piston and the cylinder wall is a dynamic seal, such as improper form and material of the selected sealing element, improper structure and size of the seal installation part, improper installation, damage to the seal or Falling off, the coaxiality of the piston and the piston rod does not meet the requirements, the working temperature is too high, and the hydraulic oil is not clean, etc., will cause the hydraulic cylinder to leak.
    2. Piston rod and piston internal leakage: The seal between the piston rod and the piston is a static seal, and the seal groove is usually opened on the shaft. Improper sealing structure design or improper selection of sealing ring may cause internal leakage.
    To sum up, there are many reasons for the leakage of hydraulic cylinders. It is necessary to analyze and take corresponding measures to reduce or avoid leakage and ensure the normal use of hydraulic cone crushers.