Oil expansion tank /ET

The oil expansion tank is designed to compensate for oil volume variations in the system caused by temperature fluctuations. When the gear unit temperature increases, the oil expansion tank absorbs some of the increasing oil volume and feeds it back to the gear unit as the temperature goes down, which means the gear unit is always completely filled with oil.

Based on the oil level specified by SEW‑EURODRIVE, the oil expansion tank is designed to compensate the oil volume change within the permitted operating temperature range. A temperature decrease below the permitted temperature range causes the oil expansion tank to be completely emptied and air being sucked into the gear unit. This can lead to insufficient lubrication and thus to failure of the gear unit. An increase above the permitted temperature range causes an overfilling of the oil expansion tank and oil might leak from the gear unit. Any oil level below or above the level specified by SEW‑EURODRIVE is permitted during operation as long as there is oil in the oil expansion tank and the oil expansion tank does not overflow.

The dimension sheets of the oil expansion tanks are provided in chapter Oil expansion tank /ET for mounting position M4.

The following figure shows the accessories for mounting positions M4 and M5 by way of example.