• Global

Cause Analysis of Poor Sealing and Bursting of Hydraulic Cylinder

The leakage of hydraulic power cylinder includes external leakage and internal leakage. 

External leakage refers to the external oil leakage at the cylinder liner, cylinder head, cylinder bottom, oil hole, automatic exhaust valve, buffer regulating valve, hydraulic cylinder head and hydraulic cylinder, which is very easy to find out from the outside immediately.

Internal leakage means that the working pressure oil in the high-pressure chamber inside the hydraulic cylinder leaks into the low-voltage chamber, which occurs at the connection between the piston rod and the cylinder chamber, and the internal thread of the piston rod and the hydraulic power cylinder.

I.  What are the reasons for poor sealing of hydraulic power cylinder?

1. The hydraulic seal is damaged due to unreasonable installation;

2. The installation precision of the hydraulic cylinder is poor, and the gap is large, resulting in the destruction of the hydraulic seal by extrusion;

3. The hydraulic seal is greatly damaged and loses the sealing effect;

4. The sealing ring orientation of the hydraulic cylinder is reversed, resulting in invalid sealing effect;

5. The sealing structure of the hydraulic power cylinder is unscientific, and the working pressure exceeds the rated current, resulting in the loss of sealing effect.

II. What are the main loads of the hydraulic power cylinder?

1. Restraining force: according to the connection mode of hydraulic cylinder and hydraulic cylinder, F = 100kN.

2. Friction and force: because the friction and force of the hydraulic cylinder are relatively small, the restraining force can be ignored.

3. Friction resistance of inertia force: the speed rate of fitness movement in the working of hydraulic power cylinder is small, which does not belong to rapid and repeated movement type, so the friction resistance of fixed inertia force can be ignored.

4. Sealing friction resistance and back pressure friction resistance: Taking the sealing friction resistance into account in the mechanical energy of the hydraulic cylinder, the mechanical energy of the hydraulic cylinder is 0.92; The back pressure friction resistance is 1MPa.

III. Cause analysis of hydraulic cylinder burst

The hydraulic cylinder can be divided into single lifting type and double lifting type. The fixed method consists of the fixed engine cylinder and the fixed hydraulic cylinder. According to the action status of the hydraulic press force, there are single effect type and double effect type.

In the single effect hydraulic cylinder, the working pressure oil is only supplied to one chamber of the hydraulic cylinder. The hydraulic working pressure makes the cylinder complete the one-way fitness movement, and the reverse fitness movement is completed by external force. The fitness exercise in two directions of the piston rod of the double effect hydraulic cylinder is carried out according to the replacement of the two cavities, which depends on the force of the hydraulic press.

1. The working pressure of gear oil is beyond the scope of hydraulic cylinder.

2. The hydraulic cylinder has minor defects in production and manufacturing, which makes it impossible to bear high pressure or long-term application under long-term load.

3. The buffer equipment in the hydraulic cylinder is damaged.

Our company has 4 friction press production lines (630-1600 tons), more than 40 precision machining equipment and heat treatment equipment such as the excavator hydraulic cylinder. JC forging can produce 0.5-50kg precision die forgings, with an annual output of 5000 tons of precision forgings. Since its establishment, JC forging has cooperated with most well-known domestic hydraulic cylinder manufacturers, and its products are exported to more than 20 countries and regions around the world. Welcome to consult.