Machine Reliability and Condition Monitoring: A Comprehensive Guide to Predictive Maintenance Planning

Reliabiltiy Analysis

Maintenance Analysis

Maintenance Policies and Strategies

R

CM promotes the use of Predictive and Risk Maintenance policies for identified critical equipment

Predictive Maintenance Techniques

Reliability KPIs

Equipment Criticality Analysis

I

mportance of Equipment Criticality Analysis involves:

Influence the priority assignment of the Work Orders.

Influence the Work Orders execution speed.

Determine which Maintenance Class should come first.

Effect the scheduling of the preventive maintenance program.

Influence the priority of the preventive maintenance work.

Help in determining which maintenance approach to be used.

Criticality Measuring Principles

Safety

✓  Safety equipment (equipment carrying peoples, firefighting system, and alike).

✓  Consequence of parts failure effect safety (elevator ropes broken, firefighting generator stopped...etc).

✓  Gas piping leakage at any point poses a risk.

Production, Process

✓  Equipment breakdown affect the whole production line.

✓  Equipment breakdown affect partially the production line.

✓  Equipment failure has native effect on production quality.

The Consequence of Failure Can Lead to Process Shutdown, Major Losses, or Quality Problem.

CRITICALITY IS INFLUENCED by the availability of standby equipment in a system but how much time does it take for the standby equipment to operate? And what is the effect of this on the production?

Time (Time=Money)

1 min production=How much?

1 Hr production  =How much?

If your equipment is classified as critical, ask yourself the following questions:

›  What is the preventive maintenance program I have for it? Enough? Or not?

›  How much time does it take to repair it in case of failure?

›  Spare parts allocation? Available? Not available? If not available, how much does it take to allocated it from the vendor?

›  Require special skills for repair? Is my team trained to repair it in a proper time?

›  Do you have an emergency plan for it in case of accident or failure? Is your team aware of this plan and trained on it?

Money, Cost

Vibration Analysis

Introduction and Terminologies

V

ibration can be defined as simply the cyclic or oscillating motion of a machine or machine component from its position of rest.

Displacement:

It is the amplitude of a point on a structure.

Velocity:

Is the speed of a point in a system, it is the rate of change of displacement.

Acceleration:

Is the rate of change of velocity of a point in a system.

Frequency:

Is the no of cycles (vibrations) per second, measured by hertz (HZ)

Harmonics:

Frequency component at a frequency that is an integer (whole number e.g., 2X. 3X. 4X, etc.) multiple of the fundamental (reference) frequency.

How many RPMs in 1 hertz?

Since hertz is in sec, and RPM is in minute, 1 hz= 60 RPM.

How to convert RPM to Hertz?

1500RPM = 25hz

Why we measure the vibration?

✓  To detect what is out of the human sense.

✓  To discover hidden failures.

✓  To Detect early failures & monitor the machine 

health condition.

✓  To assure the quality of repairs.

✓  As a useful tool to improve the maintenance 

Reliability.

Common Industrial Applications:

Pumps

Fans

Turbines

Agitators

Stirrers

Compressors

Electric Motors

Gearboxes

Vibration& Reliability

Vibration analysis alone doesn’t improve reliability, root cause analysis and acceptance testing can help.

There are two ways that we can utilize vibration to improve reliability:

First, if we study the vibration, we can often determine why the fault condition developed in the first place; for example, what caused the crack to appear in the inner race of the bearing? If we perform root cause failure analysis, we can make chances to our proactive so that the bearing doesn’t suffer the same fate in the