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The hydraulic system draws air into the oil under the continuous shear of the circulation pump; micro-foam is hard to release on its own, oil viscosity and oxidation stability swing with it, and hydraulic response and seal life suffer together.

Chemi Tech supplies defoamers for oil-based systems such as hydraulic oil and lubricating oil, drawn from the defoamer KM-860 series; the proportioning is settled jointly by the base oil type, the system additives and the operating temperature. KM-860 is compatible, knocks down foam fast once added, and does not pull the oil's own performance off course; KM-866 in the same series is a silicone system that blends with oil-based systems without separating out or clouding, and does not interfere with oil viscosity or oxidation stability. Chemi Tech completes the compatibility and foam knock-down comparison against the base oil and the additives, and recommends the model that fits for you.

Advantages of Chemi Tech Defoamers

Chemi Tech defoamer KM-860 series is compatible, and once added to the oil it neither separates out nor clouds, so the appearance and clarity of the oil stay stable; what is more, its knock-down action is solid, and micro-foam is dissolved continuously through circulation; in addition, it does not interfere with the viscosity or oxidation stability of the oil, and hydraulic response and seal life are unaffected; the dosage is low, and the addition cost is easy to control.

Industry Pain Points and Solutions

Foam in hydraulic oil is mostly not a matter of the additive being absent but of circulation shear continuously drawing air into the oil; the consequence is a swing in oil viscosity and a slower hydraulic response.

The commonest case is micro-foam held up in circulation. The shear and the drop of the circulation pump disperse air into the oil, and micro-foam has a small diameter and weak buoyancy, so it is held in the tank and hard to clear. Chemi Tech's approach is to add the compatible KM-860 at the oil return port of the tank, so that the agent is already working at the peak of air entrainment.

Next comes the appearance of the oil itself. A defoamer with insufficient compatibility separates out or clouds once added, the clarity and appearance of the oil suffer, and it may even be mistaken for oil degradation. Chemi Tech's KM-866 is a silicone system that blends with oil-based systems without separating out or clouding, and the appearance of the oil stays stable.

There is one more point in the drift of oil performance. Some categories interfere with the viscosity and oxidation stability of the oil, and over long service hydraulic response and seal life come down with it. Chemi Tech runs the compatibility comparison against the base oil and the additives, and calibrates the addition level and the top-up points, so that oil performance is not pulled off course.

Typical Conditions and Verification

Customer: a hydraulic oil producer in Guangdong, for defoaming in a circulating hydraulic oil system.

At this plant the hydraulic oil held micro-foam after circulation, bubbles built up on the tank surface, the customer reported a slower hydraulic response, and the defoamer used before caused the oil to cloud. The solution Chemi Tech defoamer provides is: against the base oil type and the additives, the KM-860 series was selected, the dosing point was set at the oil return port of the tank, and the addition level was banded by circulation volume. After the adjustment was complete, micro-foam in the oil fell noticeably, the appearance stayed clear, and the hydraulic response returned to its normal range.

Frequently Asked Questions

Will a defoamer added to hydraulic oil affect the viscosity and oxidation stability of the oil?

The concern is not unwarranted, since a few categories change the rheological properties of the oil while knocking down foam. For hydraulic oil systems, Chemi Tech has completed compatibility and oxidation stability comparisons with the KM-860 series, and at normal addition levels oil performance is unaffected. The addition level depends on the base oil and the additives, and Chemi Tech gives the recommended dosage after the oxidation stability comparison.