Mechanical
☞ The valve seal is loose, causing air to leak in;
☞ A loose shaft seal on a pump, resulting in air leakage;
☞ Leakage in piping, swivel connections, or other connections, resulting in air leakage;
☞ Pinhole in the hose;
☞ Bypass valves too close together, creating extreme back pressure in the system;
☞ A powerful pump that exceeds the operating requirements, creating agitation in the system;
☞ The reservoir is too shallow or the pump is placed too high, causing the pump to draw air;
☞ Reverse rotation of the pump for processing fluids;
☞ Excessive spraying creates an impact at the liquid level in the tank.
For machining oil
☞ Appropriateness of coolant selected and concentration used;
☞ Contamination of oil leaking from the machine tool;
☞ Contamination from cleaning fluid or soap used for floor washing;
☞ The quality of water and its proper mixing with the coolant;
☞Antifoamer will be consumed by the system. To control foam well, it is necessary to continuously put in a quantitative amount of antifoamer, and using it incorrectly or in excess of ☞use of antifoamer is likely to be counterproductive;
☞ Problems from other processes, such as stretching or mold release agents sticking to the surface of the part.
Translated with DeepL.com (free version)
