Rotating Fatigue Testing Apparatus Model MT 076

Sci-tech Rotating Fatigue Testing Apparatus Model MT 076 has been designed to introduce students to the effects of material fatigue using a sinusoidal variation of bending stress. A 2800rpm motor rotates a specimen through a gear and pulley arrangement between 5600 or 1425 rpm. The specimens are held within ‘keyless’ chucks and loaded using a cantilever arrangement, with the load being applied through a screw jack mechanism with integral cantilever load cell. The applied force is captured on the ‘on-board’ digital display along with the revolution count of the specimen. Both values can be reset and zeroed (tared) prior to the testing commencing. When failure occurs, a micro-switch stops the motor and the cycles to failure are registered on the digital display. The count remains when the motor is not running and the ability to reset the counter has been designed in. A safety guard shields all rotating parts.

Size: 110cm x 50cm x 50cm (LxWxH)
Weight: 35 kg

Item Description

Sci-tech Rotating Fatigue Testing Apparatus Model MT 076 has been designed to introduce students to the effects of material fatigue using a sinusoidal variation of bending stress. A 2800rpm motor rotates a specimen through a gear and pulley arrangement between 5600 or 1425 rpm. The specimens are held within ‘keyless’ chucks and loaded using a cantilever arrangement, with the load being applied through a screw jack mechanism with integral cantilever load cell. The applied force is captured on the ‘on-board’ digital display along with the revolution count of the specimen. Both values can be reset and zeroed (tared) prior to the testing commencing. When failure occurs, a micro-switch stops the motor and the cycles to failure are registered on the digital display. The count remains when the motor is not running and the ability to reset the counter has been designed in. A safety guard shields all rotating parts.

Optionally digital display incorporates a USB socket, which allows a host computer (not supplied) to be connected to the apparatus. The software supplied with the apparatus allows the capture and reviewing of data. Through an appropriate spread-sheet software (not supplied), printing and manipulation of data can be completed.

Specially machined necked test specimens are provided in steel. These have a 4mm nominal neck diameter and are held in the unit using collet chucks. All tooling is provided to allow the removal and fitting of these specimens. A full technical instruction manual is supplied, which details full unit operation, experimental technique, example results and relevant theory.

Technical Specifications

Specifications

  • To demonstrate the effects of fatigue
  • To be self-contained bench top unit on sturdy, heavy base plate
  • To be data acquisitioned for capturing applied force, specimen revolutions
  • Optional Data Acquisition software supplied
  • To test necked specimens of different materials
  • To be fully guarded in order to restrain fractured specimen
  • Rotate a loaded cantilever until failure occurs in rupture
  • Specimen loading via screw jack mechanism with integral cantilever load cell
  • Rotational speeds variable through gear ratios
  • To have digital display of specimen revolutions, applied force on specimen
  • Motor to stop automatically on specimen failure
  • Reset and tare function for digital display
  • To be supplied with mild steel test specimens
  • Comprehensive technical manual

 

Technical Specifications

  • Motor speeds: 5600 or 1400rpm (approximately)
  • Motor speed: 2800rpm nominal
  • On-board starter box
  • Timing pulley and belt drive system: 20t and 40t
  • 10 x Standard specimens: Ø4mm neck diameter x 65(L) mm, steel
  • Cantilever loading arrangement
  • Clear safety guard
  • Safety: Motor will remain inactive with safety guard removed

 

Experiments

  1. To make an introductory study of fatigue using a Wohler rotating fatigue apparatus, including the time to failure caused by various stress levels and materials
  2. Introducing students to S-N curves
  3. Material specification on fatigue limits
  4. Specimen geometry on fatigue limit
  5. The accessory affords bending fatigue of a cantilevered strip of metal or plastic in modes varying from alternating to fluctuating stresses

Model Number

MT 076