CNC milling machine oil leakage can be divided into three states: leakage, dripping, and flowing oil. In general, a drop of oil every 0.5 hours at the static joint surface and a drop of oil every 6 minutes at the dynamic joint surface are considered leaks. Whether it is a dynamic or static joint surface, when a drop of oil is dropped every 2-3 minutes, it is called oil dripping; More than 5 drops per minute are considered flowing oil. The general requirement for achieving leak control of equipment is that there should be no leakage at the static joint surface outside the equipment, and slight leakage is allowed at the dynamic joint surface, but it is not allowed to flow onto the ground. Some leakage is allowed inside the equipment, but it is not allowed to seep into the electrical box and drive belt. It can be led back into the lubrication box.
Oil leakage may occur during CNC machining, and it is easy to identify the location of the oil leakage in the machining center. Mainly because it is caused by accessories or oil leakage from the cylinder of the CNC lathe. If it is an accessory, maintenance is very simple. If it is a cylinder and it is troublesome, it can seriously lead to the scrapping of the machine tool. Let's now study the reasons for oil leakage in CNC machining centers?
1. The oil replaced on the CNC lathe does not meet the requirements.
The oil replaced on the CNC lathe does not meet the requirements, which can greatly cause oil leakage in the CNC machining center. The problems that occur during oil change mainly manifest in three aspects. Firstly, for components that use high viscosity lubricating oil, randomly switching to low viscosity lubricating oil during oil change can have a certain impact on the sealing performance of the corresponding housing, shaft holes, etc., sometimes greatly reducing the sealing performance of these parts. Secondly, if the oil tank is not cleaned after CNC lathe machining and oil change, the dirt in the oil tank may enter the lubrication system, block the oil circuit, wear the seals, and cause oil leakage. Thirdly, when changing oil, adding too much oil, especially in areas with rotating parts, is more likely to cause oil spillage due to the stirring effect of the rotating parts.
2. Improper selection and adjustment of lubrication system components can cause oil leakage.
For example, when CNC machining maintenance personnel use oil pumps with high pressure or excessive oil output during maintenance, or when adjusting system pressure, the pressure adjustment of overflow valves, safety valves, pressure reducing valves, etc. is too high, and the flow rate of the CNC machine tool lubrication system is too large, which does not match the return oil system and sealing system, resulting in oil leakage.

In fact, it is not just the above points that cause oil leakage in CNC machining centers. If we encounter similar problems during operation, we must do a good job of inspection, timely find the cause, and avoid unnecessary losses. After purchasing the machining center, conduct a comprehensive inspection to see if there are any casting defects or damaged parts. If so, contact the manufacturer in a timely manner. When operators use CNC machining centers to process workpieces, they should also pay attention to the following points:
(1) For the first trial cutting process of CNC machining, a single-stage operation mode should be used for processing.
(2) When the automatic operation of the CNC milling machine starts, the fast magnification and feed magnification S are in the lowest gear, and then the efficiency is improved after cutting into the workpiece.
(3) In the operation of CNC milling programs, attention should be paid to the coordinate display of the CNC system.
(4) Do not touch CNC milling machine tools and chips with your hands. The chip must be cleaned with a brush.