Bearings; Axial And Radial Forces; Balancing - Siemens SIMOTICS XP 1MB 1 Series Operating Instructions Manual

Surface cooling by relative movement of cooling air: Cooling method IC 418 according to
EN / IEC 60034-6
3.3.3

Bearings

To support the machine shaft and maintain its position in the non-moving part of the machine,
DE and NDE rolling bearings are used. One end performs the function of a locating bearing that
transfers axial and radial forces from the rotating machine shaft to the non-moving part of the
machine. The opposite end is implemented as a floating and support bearing to allow thermal
expansion inside the machine and transfer radial forces.
The nominal (theoretical) service life of the bearings according to ISO 281 is at least 20,000
hours when the permissible radial/axial forces are complied with, and the machine is operated
on 50 Hz line supplies. However, the achievable useful life of the bearings can be significantly
longer in the case of lower forces (e.g. operation with self-aligning couplings).
Rolling bearings with permanent lubrication are maintenance-free.
3.3.4

Axial and radial forces

Permissible values for axial and radial forces are listed in the catalog or stamped on the rating
plate depending on the type of construction / mounting type. The data stamped on the rating
plate have priority.
Damage to bearings or the shaft
Large output masses and their centers of gravity outside the shaft extensions can lead to
resonance in operation. This can result in damage to the bearings and shaft. In an explosive
atmosphere, there is a risk of explosion. Death, serious injury, or material damage can result.
• Ensure that the permissible loads for the forces on the shaft extension are adhered to in
• Under all circumstances, maintain the minimum radial load of cylindrical rolling bearings of
The machine is equipped with grease-lubricated rolling bearings.
• In the standard version, the bearings of machines up to shaft height 250 are permanently
lubricated.
• The bearings of machines from shaft height 280 and above are equipped with a relubrication
system.
3.3.5

Balancing

As standard, the machine is designed with vibration severity level A. The rotor is dynamically
balanced with a half feather key (code "H").
Vibration severity level B can be ordered as option, and stamped on the rating plate.
1MB..1/2/3/4 - shaft heights 63 ... 355
Operating Instructions, 11/2023, A5E52779900A
WARNING
accordance with the catalog data or configuration data.
50 % of the permissible radial force.
Description
3.3 Installation
31