Whirling Shaft Apparatus & Accessories Model MT 111

Sci-tech Whirling Shaft Apparatus Model MT 111 experimental unit teaches knowledge about how to determine the critical speeds. Illustrative experiments are used to explain resonance and supercritical or subcritical states of a vibrating system. A three-phase motor drives a rotor shaft, onto which one or two masses may be fixed at various distances. The rotor shaft is mounted in two self-aligning ball bearings and connected to the motor via a flexible coupling. The electronically regulated speed can be selected via two potentiometers and is continuously variable. It is displayed on a digital readout by a revolution counter. The position and distances to elements fixed onto the rotor shaft can be read on a scale mounted in parallel to the rotor shaft. A transparent protective cover and safety bearing immediately next to the masses attached to the rotor shaft ensure safe operation. Sci-tech Whirling Shaft Apparatus Model 111 accessory comes with measurement and evaluation software, including sensors, for data capture via PC. Supply Sensor Module needs to be connected for data acquisition.

Size: 120cm x 40cm x 40cm (LxWxH)
Weight: 25 kg

Item Description

Features

* Investigation of simply loaded & continuous shafts
* Determining critical speeds1
* Position of rotor mount and rotating mass can be adjusted1
* Optimal visibility and simultaneous protection thanks to transparent protective cover

 At a certain speed the imbalance forces of a rotating mass can cause part of the machine or the entire machine to vibrate in resonance with bending vibrations. This speed is known as the critical speed. The rotor and shaft on a motor or a turbine, for example, form a system that can resonate. In rapidly rotating machinery this state presents a danger because it can lead to breakage and damage to the components of the system. To prevent this, the system is operated well above or below the critical speed and quickly driven through the critical speed range. Structural changes, e.g. changes to rigidity, can cause the critical speed to change, meaning the operational requirements have to be adapted.
Sci-tech Whirling Shaft Apparatus Model MT 111 experimental unit teaches knowledge about how to determine the critical speeds. Illustrative experiments are used to explain resonance and supercritical or subcritical states of a vibrating system.
A three-phase motor drives a rotor shaft, onto which one or two masses may be fixed at various distances. The rotor shaft is mounted in two self-aligning ball bearings and connected to the motor via a flexible coupling. The electronically regulated speed can be selected via two potentiometers and is continuously variable. It is displayed on a digital readout by a revolution counter. The position and distances to elements fixed onto the rotor shaft can be read on a scale mounted in parallel to the rotor shaft.

A transparent protective cover and safety bearing immediately next to the masses attached to the rotor shaft ensure safe operation. 
Sci-tech Whirling Shaft Apparatus Model 111 accessory comes with measurement and evaluation software, including sensors, for data capture via PC. Supply Sensor Module needs to be connected for data acquisition. 
The well-structured instructional material sets out the fundamentals and provides a step-by-step guide through the experiments.

Technical Specifications

Specifications

[1] Investigation of simply loaded & continuous shafts
[2] Two self-aligning ball bearings moveable to any point as the rotor shaft mount
[3] Two masses that can be fixed at any point 
[4] Safety bearing and transparent protective cover for safe operation
[5] Two pre-selectable speed ranges, speed electronically regulated and infinitely adjustable
[6] Digital speed indicator
[7] Two options for data acquisition: either vibration sensors with supply unit for connection to an oscilloscope or data acquisition system including software and sensors

 

 

 

Technical Specifications

Three-phase motor
– power 0,37kW
– max. speed 6000min-1 
Rotor shaft
– L=500mm
– D=6mm
– hardened steel
2x mass, disc-shaped
– m=965g
– D=80mm
– hardened steel
Shaft mount
– 2x self-aligning ball bearings
– 2x safety bearings

 

Measuring ranges 
– speed: 300…3000min-1
– scale for measuring distance: 0…500mm

 

Optional

Vibration Sensors with Clamping

  • Non-Contact Inductive Position Sensor, 2 cylindrical inductive linear sensors,
  • Operating range 5…10mm, Reference distance 7.1…7.9mm, Sensitivity 1.6V/mm, Slew rate 1.5/ms, Frequency range 0…50Hz, Output signal 1…9V DC proportional,
  • Fitted with 7-pole plug, fitted with clamping set, wrench span 36mm diam. x l: 30mm i.dia. x 60mm, approx. 0.25kg

Sensor Supply Module  

  • Benchtop unit to supply power and to condition measured data from inductive vibration sensors; analogue output signal voltage: 1…9V, output on 4mm laboratory sockets, signals are displayed on an oscilloscope

Oscilloscope

  • 70Mhz Digital Storage Oscilloscope

 

Optional Accessories

  1. Sci-tech Sensor Supply Module Model MT 111S
  2. Vibration Sensors with Clamping Set Model MT 111VS

 

 

Experiments

  1. Investigation of simply loaded & continuous shafts
  2. Determination of critical speeds with different arrangements of the bearing and masses on the rotor shaft
  3. Investigation of the rotor shaft’s self-centering effect

Model Number

MT 111