investigation of the natural modes of various shafts with continuous mass distribution and of a Laval rotor

Description:

• The terms “critical speed” and “resonance” are often used when referring to rotating systems.
• Resonance occurs when the natural frequency and the excitation frequency match.
• The natural frequency of an oscillatory system is that frequency at which the system oscillates with the associated natural mode after a single excitation.
• Operation at critical speed can damage the system because of the high vibration amplitudes.
• In order to study the phenomenon of shaft vibration in more detail, there are two simplified calculation models.
• In the first case, the mass of the elastic shaft is evenly distributed along its length.
• In the second case, the shaft consists of massless, elastic shaft sections and the masses are combined into discrete mass disks.
• The TM 625experimental unit can be used to study the natural modes of these different models.
• Illustrative experiments are used to explain resonance and the supercritical or subcritical states of a vibrating system.
• Six shafts of different lengths and diameters are available.
• The shafts can be mounted on four self-aligning ball bearings and fitted with a mass disk to construct a Laval rotor.
• The axial positions are read on a scale mounted parallel to the shaft.
• A three-phase motor drives the shaft via a flexible coupling.
• The electronically controlled speed can be selected via two potentiometers and is continuously variable.
• It is displayed digitally.
• A transparent protective cover and safety bearing ensure safe operation.
• The measured values can be displayed and analysed on a PC using the optional TM 620.20unit for data acquisition.

Technical Details:

Specification:

• experimental unit for determining critical speeds and investigating the natural modes of a shaft
• 6 high-tensile steel shafts
• up to 4 self-aligning ball bearings, each moveable to any point as a shaft bearing
• 1 mass for constructing a Laval rotor
• 3 safety bearings and transparent protective cover for safe operation
• three-phase motor: 2 pre-selectable speed ranges; speed electronically controlled and continuously adjustable
• digital speed display
• system TM 620.20 for data acquisition available as an option

Technical Data:

• 6 shafts
  • Ø 3mm, 6mm, 7mm
  • L: 600mm, 900mm
  • high-tensile steel
• Mass, disk-shaped
  • Ø 80mm
  • m: 965g
  • high-tensile steel
• Motor
  • power: 0,25kW
  • speed: 6000min^-1
  • speed electronically controlled
• Shaft bearing
• 4x self-aligning ball bearings
• 3x safety bearings
• Measuring ranges
• speed: 0…6000min^-1
• scale for clearance measurement: 0…1000mm
• 230V, 50Hz, 1 phase
• 230V, 60Hz, 1 phase; 120V, 60Hz, 1 phase
• UL/CSA optional

Dimensions & Weight:

• L x W x H: 1550x380x450mm
• Weight: approx. 65kg

Learning Objectives/Experiments:

• investigation of a Laval rotor:
  • critical speed
  • self-alignment
• natural modes on a shaft with continuous mass distribution with:
  • different bearing clearances
  • different shaft diameters
  • different shaft lengths

Scope of Delivery:

• 1 experimental unit
• 6 shafts
• 1 set of tools
• 1 set of instructional material

Features:

• optimal visibility and simultaneous protection thanks to transparent protective cover

Accessories:

• Optional:
• TM 620.20System for data acquisition
• WP 300.09Laboratory trolley

Due to the continuous development of our products, the goods supplied may vary in detail to that illustrated on this Website.