Preventative Maintenance System

Preventive vs. Predictive vs. Prescriptive Maintenance

It is no secret that unplanned downtime is the bane of existence for many manufacturers, and that simply relying on conventional run-to-failure maintenance schemes is the costliest method for plant maintenance overall. Many manufacturers have implemented preventative maintenance programs to reduce the occurrences of unplanned downtime, but there are shortcomings to this approach as well. This has led more manufacturers to attempt to implement predictive maintenance programs or even
prescriptive maintenance programs. However, there are cost implications that will need to be factored into determining what makes the most sense for your facility

What's in a name?

It's important to understand exactly what each maintenance program warrants to determine which plan makes the most sense for your facility.

Preventative maintenance: This type of program involves creating an equipment maintenance plan that is based on knowing the historical performance of the equipment to determine when (and what type of) maintenance is required. This is typically provided by the manufacturer of the equipment and is based on mean
time between failure (MTBF) and mean time to repair (MTTR) data for major components. This (theoretically) allows for planned maintenance during a period that is least disruptive to operations. It is also a concept well understood by most manufacturers.

This is a great system if your equipment performance is average. However, there are many factors that could cause a premature failure resulting in unplanned downtime. Conversely, this system might result in premature maintenance, which means you could be performing maintenance tasks too often. Ideally, you would like to know the actual device health at any given moment to know precisely the best time to perform a maintenance task. This is where the concept of predictive maintenance comes in.

Predictive maintenance:

This type of program involves the use of sensors to monitor actual device health in real time and make maintenance decisions based on the actual performance data rather than "average" data. The average data is still useful as a baseline, and then actual data is compared to the historical in order to make the best predictions on when maintenance should be performed. To be most effective you need to have sensors everywhere, and then be able to analyze the huge amount of data – in real time - that will be generated to glean appropriate insights.

Most modern machinery contains sensors that can be used for this analysis, and "add-on" sensors are readily available and relatively inexpensive. The greater expense is in the data storage and analytics software required. This sometimes results in a system that periodically collects data that is then fed into a system for
analyzing. Depending on the measurement intervals, this could be just fine for many applications but is not as accurate as continuous monitoring.

All About Condition Monitoring

Vibration : Because vibration is the most common symptom of imbalance, misalignment and other anomalies, predictive maintenance is often machines such as motors, pumps, spindles, conveyors, manufacturing machines, and fans.

  • Frequency Frequency means the number of time that vibrating object generates a repetitive motion in 1 second.
    • Unit: Hz
  • Displacement
    • Unit: μm, mm
  • Acceleration
    • Unit: m/s2 , g
  • Temperature
    • Unit: Deg Celsius
  • Noise
    • Unit: db.

Smart Factory Platform

Measurement Method

There are two types of vibration measurement methods "Permanent online vibration monitoring system" and "Portable off-line monitoring system". Either one is selected generally depending on importance rank of equipment.

1. Online Monitoring :

Machinery that : is important

  • Operates Constantly
  • Cannot be Approached
  • Deteriorates Slowly

2. Offline Monitoring

Machinery that : is important

  • Is Minimal impact from Breakdown
  • Is Easy to be Measured
  • Deteriorates Quickly

Feature , Use and Application of CBM

What is FFT ( Fast Fourier Transform ) ?

FFT is one method of analysis, based on vibration waveform. Generally, waveforms are complicated and difficult to analyze. In FFT, we break waveforms down into a series of discrete sin waves, and evaluate each individually.

When a machine functions abnormally for eg: due to imbalance or damage . It will produce different vibrations that can be detected using FFT

Advantages and Benefits

APPLICATION AREAS

Market Information

Players in market having Predictive
Maintenance IOT based solutions:

  • Up KEEP
  • SAP. ...
  • Siemens. ...
  • Microsoft. ...
  • GE. ...
  • C3 IoT. ...
  • Uptake. ...
  • Space Time Insight.

Solutions Available in market

  • Predictive-Sigma – Smart Predictive Maintenance
  • Semiotic Labs – Smart Condition Monitoring
  • Presenso – Predictive Analytics
  • Seebo – Root Cause Analysis
  • Industrial Analytics – Digital Twin