Standard Type Plummer Blocks
SN5 and SN6 types are the most common type, which are provided for in JIS B 1551, ISO 113/II, and DIN736, 737. SN30 and SN31 types are medium size and their shaft diameters are bigger than that of SN5 and SN6 types. For these types, a bearing is mounted with the use of an adapter.
Large Plummer Blocks
These are large size and for heavy-duty application. They have dual structure oil seals. For these types, a bearing is mounted with the use of an adapter.
Dustproof Plummer Blocks
This is a dustproof type, and this was
developed by NSK. It has a combination of oil seals, labyrinth seals, and oil
groove seals; therefore, it is suitable for environments with dust and other
For this type, a bearing is mounted with the use of an adapter.
Stepped-Shaft Type Plummer BlocksSN2C and SN3C are the types that the bore diameter of one side is smaller than that of SNa2 and SN3 respectively, and they are provided for in JIS B 1551. For these types, a bearing is mounted with the use of a nut and washer.