A company manufactures railway wheels. After forging, the wheels require further machining in large machining centres. Three of these machining centres share a central coolant supply system located in a basement beneath the machines. Because machining places heavy demands on the coolant, the system has a total capacity of 16,000 litres.
The company’s oil supplier alerted the maintenance manager to rising levels of tramp oil in the system coolant. Frequent leaks in the hydraulic equipment had introduced more than 1,000 litres of foreign oil into the coolant in some cases. The maintenance team therefore needed an effective solution to remove this contamination.
Although the reservoir was large enough for an oil skimmer, turbulence in the coolant system was too high for a stable oil layer to form. A bypass separator was therefore required.
The system consists of two physically separate 8,000-litre reservoirs, so the customer was supplied with two Skimmtelligent 20 oil separators.
The existing filtration system comprised only a single magnetic roller. Both oil separators were therefore equipped with magnetic filters to improve coolant quality further.
Each separator draws coolant from a basement reservoir. The magnetic filter first removes ferrous particles. The coolant is then pumped into the bypass separator, where the flow can settle and a separate oil phase forms for removal.
Coalescing elements inside the separators accelerate the rise of tramp oil. Oil droplets collect on their surfaces and combine into larger drops. The increased buoyancy allows the oil phase to form more quickly. Even very small droplets rise, resulting in more thorough oil removal from the coolant.
After an extended rental trial, both the maintenance manager and the oil supplier were convinced by the separators’ performance. Coolant testing showed a significant reduction in tramp-oil concentration. Particle contamination also fell because the magnetic filters provided more effective filtration.
