Guideline values of specification life for different machine types
| Machine type | Specification life |
| Operating hours | |
| Household machines, agricultural machines, instruments, technical equipment for medical use | 300 ... 3 000 |
| Machines used for short periods or intermittently: electric hand tools, lifting tackle in workshops, construction
equipment and machines |
3000 ... 8 000 |
| Machines used for short periods or intermittently where high operational reliability is required: lifts (elevators),
cranes for packaged goods or slings of drums, etc. |
8 000 ... 12 000 |
| Machines for use 8 hours a day, but not always fully utilized: gear drives for general purposes, electric motors
for industrial use, rotary crushers |
10 000 ... 25 000 |
| Machines for use 8 hours a day and fully utilized: machine tools, woodworking machines, machines for the
engineering industry, cranes for bulk materials, ventilator fans, conveyor belts, printing equipment, separators and centrifuges |
20 000 ... 30 000 |
| Machines for continuous 24-hour use: rolling mill gear units, medium-sized electrical machinery, compressors,
mine hoists, pumps, textile machinery |
40 000 ... 50 000 |
| Wind energy machinery, this includes main shaft, yaw, pitching gearbox, generator bearings | 30 000 ... 100 000 |
| Water works machinery, rotary furnaces, cable stranding machines, propulsion machinery for ocean-going vessels
|
60 000 ... 100 000 |
| Large electric machines, power generation plant, mine pumps, mine ventilator fans, tunnel shaft bearings for
ocean-going vessels |
100 000 ... 200 000 |
