Bruker BioSpec 70/30 USR V2, Руководство пользователя

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Laboratory Infrastructure and Interactions
Site Planning Information BioSpec 70/30 USR_2_V020 35
Figure 5.4: Limit values of the floor vibrations
1 Maximum acceptable floor vibrations at the installation site
2 Typical distribution of a magnet system's tolerance to floor vibrations
Frequency range max. acceptable acceleration (mm/s2)
0 – 5 Hz 0.15 mm/s
2
5 – 10 Hz 1.00 mm/s
2
10-20 Hz 8.00 mm/s
2
> 20 Hz 50.0 mm/s
2
Table 5.9: Max. acceptable accelerations within different frequency ranges
Countermeasure
The safest countermeasure is the avoidance of increased floor vibrations at the magnet's
installation site. If this cannot be avoided, countermeasures concerning the building structure
and floor construction can also be taken by the builder.
The following points have proven to be advantageous when selecting a suitable installation
site:
• The magnet foundation should be firmly connected to the floor
• Floor plates and ceilings that span large areas are prone to higher floor vibrations,
therefore installation in corners of buildings is beneficial
• Installations on lower floors can be achieved uncritically compared with installations on
higher levels
• Avoid areas of non-decoupled elevators and heavily used transport routes within the
building
• Railway/subway lines should be more than 40 m away from the building
If none of the alternatives mentioned can be realized, additional passive or active vibration
decoupling must be evaluated by the builder. Please contact an engineering firm specializing
in building vibrations for this and contact your local Bruker BioSpin MRI branch.