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Sheet Metal Processing Machinery and Equipment Oil Leakage | Causes And Solutions

During long-term operation, sheet metal processing machinery and equipment will gradually age and wear due to its own structure, materials and other reasons, causing problems such as loose sealing, leading to oil leakage. Improper equipment maintenance is also a common cause of oil leakage from equipment.


If sheet metal processing equipment does not undergo timely and effective maintenance, the service life of oil seals and other seals may be greatly shortened, resulting in oil leakage. Oil leakage from equipment will not only affect production efficiency, but will also have a certain impact on the environment. If companies want to avoid this problem, they need to develop comprehensive prevention and control measures.


So what are the reasons for oil leakage from sheet metal processing machinery and equipment? How to deal with it?

1. Unreasonable design and selection lead to oil seal failure and leakage

Different types of sheet metal machinery and equipment are used in different environments, the lubricating oil used is of different quality, and the chemical composition of the oil is also different.


The chemical composition of the oil used was not considered in the design, and oil seals made of ordinary materials were used. After installation, the oil seal quickly fails due to chemical corrosion, causing oil leakage. Replacing it takes time and effort.

CNC press brake bending machine hydraulic pipe line

Take the press brake bending machine as an example:

This is a working process in which the pressure generated by the hydraulic system is transmitted through the mold to finally obtain the required material shape.


Therefore, 46# and 32# anti-wear hydraulic oil must be used to properly lubricate the bending machine, improve the working efficiency of the equipment, reduce machine tool wear, and extend the use of the equipment.



When overhauling equipment, the environment and lubricating oil used by the equipment should be fully considered. Choose the appropriate oil seal for replacement to extend its service life.

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2. Low manufacturing accuracy or improper maintenance

In the processing or maintenance of shaft parts, the bearing installation position generally receives more attention, while the processing of the oil seal installation position is often ignored. The location was roughly machined or improperly maintained, resulting in localized damage. When the equipment is running, problems with the machine body cause the lip of the oil seal to quickly become damaged and fail, causing oil leakage.


For example, after long-term use of a bending machine, the oil cylinder is prone to wear and tear, resulting in poor sealing and oil leakage. Wear can be caused by friction or particles and dirt that accumulate during use.



Therefore, during processing or maintenance, the accuracy and roughness of the oil seal working area should be strictly controlled to ensure the processing quality here and maintain the long-term effective operation of the oil seal.


3. The exhaust cap configuration is unreasonable, and there is positive pressure gas in the oil pool or equipment box

This problem is mainly caused by unreasonable design and manufacturing. During the operation of sheet metal processing machinery and equipment, friction generates heat, the temperature rises, and the molecules in the lubricating oil vaporize. If the gas is not discharged from the oil pool or box in a timely and reasonable manner, positive pressure will be formed, resulting in lax sealing and oil leakage.


Usually, the exhaust cap is installed on the top of the device. However, due to unreasonable temperature selection and calculation in the design, the exhaust cap did not discharge all the gas generated out of the box in time, resulting in positive pressure in the box.



The solution is to enlarge the exhaust hole on the exhaust cover so that the positive pressure gas can be discharged in a timely and reasonable manner.


In another case, lubricating oil leaks out of the exhaust cap along with the gas. In this case, the duct of the exhaust cap needs to be lengthened so that the oil-air mixture can be fully cooled, and then the lubricating oil can return to the box instead of being discharged together with the gas.


4. The design of the oil return hole through the bearing cover is unreasonable

Guillotine plate shearing machine hydraulic pipe line

For oil-lubricated equipment, in order to ensure that the bearings are fully lubricated, designers consider how to provide sufficient lubricating oil to the bearings. However, how to return the lubricating oil to the tank shell has not been fully considered.


The lubricating oil from the bearing cannot flow back into the tank shell in time, and the space between the bearing and the cover accumulates, breaks the seal, and leaks out as the shaft rotates.



The solution is to enlarge the oil return hole and set up a reasonable oil guide groove to allow the oil to flow back to the fuel tank shell in a timely and reasonable manner.


5. Unreasonable configuration of oil inlet and outlet pipelines causes oil leakage

For equipment with circulating oil supply and lubrication, the oil supply pipeline is generally smaller and the oil return pipeline is larger. The oil return pipeline must have a certain downward slope when installed to minimize elbows.


Otherwise, the oil return will not be smooth, and excessive oil will accumulate at the lubrication point to form positive pressure, causing oil leakage or oil leakage.


6. Improper operation methods cause oil leakage

For normal operation of equipment with a lubricating oil station, the lubricating oil should be heated to a certain temperature before turning on the oil pump for lubrication. This is extremely important in cold northern areas in winter.


As the temperature of lubricating oil decreases, the viscosity increases and the fluidity becomes worse. At this time, if the oil pump is started for lubrication, the oil supply pressure will increase. One is causing oil leakage. The second is to damage the oil seal. Third, the oil supply equipment is damaged.



In the cold northern regions, it is best to heat and insulate the oil supply and return pipelines to facilitate smooth flow of the oil lines.


7. The upper and lower box seals fail

Generally speaking, there are two reasons for this situation:

① During assembly or maintenance, local damage to the joint surface of the box or partial damage to the sealing gasket is caused.

② The sealing gasket has been used for too long and seems to be in good condition without being replaced during maintenance, resulting in sealing failure.


When the cnc hydraulic press brake is working, the oil in the oil cylinder needs to maintain pressure to ensure its smooth operation. If the seal of the oil cylinder is poor, it will cause oil leakage and even failure to form pressure. Common causes of poor sealing include aging of the gasket, damage to the sealing surface, etc.



The solution is to disassemble the device, identify the problem, repair it and reseal it.


If the cylinder leaks due to poor sealing, the sealing gasket can be replaced first. There are many types of seals on the market, including rubber seals, silicone rubber seals, etc., which can be selected according to the specific conditions of the bending machine.


If there is minor damage to the cylinder sealing surface, it can be repaired with fluid sealant.


8. Oil leakage at the oil pipe joint

This problem is usually caused by the oil pipe not being fixed securely, and the vibration of the equipment during operation causing the oil pipe joint to loosen. Special attention should be paid to the fact that the oil return pipeline is installed close to the ground in most cases. Be sure to reinforce the protection to prevent people from stepping on it and causing oil leakage.


The connection of the bending machine oil pipe may be loose or have poor contact, which may also lead to oil leakage. If the oil pipe connection is poor, the oil pipe or connecting parts need to be replaced in time.


The above are the eight main aspects, and there are some other issues. Most of them are related to each other, but they are expressed in different forms. As long as every mechanical equipment management worker carefully analyzes different situations and takes corresponding measures, the problems of oil leakage and oil leakage in the sheet metal forming machinery and equipment can be solved.


The solutions mentioned in this article are only part of them. Enterprises can formulate more effective plans based on their own actual conditions to avoid sheet metal processing machinery and equipment oil leakage problems.

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