Renold Gears

  • Company: Renold Gears
  • Industry: Rail
  • Services: Vibration Analysis, Machinery Health Analyser, Cloud-based Reporting
  • Location: London, United Kingdom
  • Cost-Saving: £8,000

The Overview

A condition monitoring survey on an escalator highlighted an inner race bearing fault on a worm box input shaft thrust bearing. By preventing an unexpected failure, it was estimated that the client saved £8,000 in repair costs and potential penalty fees.

The Situation

We carried out a condition monitoring survey on two escalator drive gear trains at Tottenham Court Road tube station. The survey was performed on a newly-fitted gearbox on behalf of a gearbox manufacturer in the UK.

The Challenges

Following reports of unexpected vibration and deflection during operation, a condition monitoring survey was undertaken to confirm if any adverse or unwanted vibration was being experienced on a newly installed gearbox, in order to prevent an unexpected breakdown during peak operation times.

The Solution

Standard vibration and stresswave data was collected by one of our reliability engineers using an Emerson 2140 Machinery Health Analyser. The analyser was fitted with a 00mV/g accelerometer with a dual rail magnet mount.

The data was analysed and a detailed report was sent to the client along with recommendations and feedback.

The Results

Analysis of the vibration and stress wave data revealed an inner race bearing fault on the RH worm box input shaft thrust bearing (6312) - see figure 1.

Figure 1: RH input shaft worm box stress wave spectrum

While stresswave levels were low, due to the criticality of the asset the bearings were recommended for overhaul to prevent an in service failure.

The bearing was replaced during scheduled maintenance by London Underground engineers.

By preventing an unexpected failure, it was estimated that the client saved £8,000 in repair costs and potential penalty fees.

As a result of the cost avoidance, the client recommended we carry out further routine monitoring on other escalators in the London Underground network.