For many pump drives, such as the steam turbine bearing housing shown, synthetic VG 32 can also be used as an advantage.

The sleeve bearings on the drive side of this small turbine are process-lubricated with VG 32 lubricants, while the rolling bearings (thrust bearings) on the governor side can use VG 68 oil if possible.

Due to its good performance, VG 32 synthetic lubricant has the viscosity required for reasonable oil ring performance, as well as the oil film thickness and strength characteristics required to increase bearing life.

Here are some general guidelines to consider:

The use of mineral oil usually requires oil changes every 6 to 12 months. With clean, good synthetic lubricants, you usually increase the oil change interval to at least 24 months. Combined with the bearing case protector seal shown in the figure and preventing contamination from entering the vent holes, a 36-month replacement interval can be achieved.

For pump bearings, ISO 32 grade mineral oil is generally considered too "lean". They are used for long periods in pumps equipped with rolling bearings under typical environmental conditions. However, for those bearings that rely on oil rings for process lubrication, a simple conversion to ISO 68 mineral oil would be risky.

From the perspective of film strength and film thickness, ISO VG 32 synthetic materials properly formulated with the correct base oil and proprietary additives are acceptable. In fact, some ISO VG 32 synthetic oils perform as well as ISO VG 68 mineral oils.