EXAMPLES

Operation O

An operation occurs when an object is intentionally changed in one or more of its characteristics

(physical or chemical). This indicates the main steps in a process, method or procedure.

An operation always takes the object one stage ahead towards completion.

Examples of operation are:

Turning, drilling, milling, etc.

A chemical reaction.

Welding, brazing and riveting.

Lifting, loading, unloading.

Getting instructions from supervisor.

Taking dictation.

Inspection

An inspection occurs when an object is examined and compared with standard for quality

and quantity. The inspection examples are:

Visual observations for finish.

Count of quantity of incoming material.

Checking the dimensions.

Transportation →

A transport indicates the movement of workers, materials or equipment from one place to

another.

Example: Movement of materials from one work station to another.

Workers travelling to bring tools.

Delay D: Delay (Temporary Storage)

A delay occurs when the immediate performance of the next planned thing does not take

place.

Example: Work waiting between consecutive operations.

Workers waiting at tool cribs.

Operators waiting for instructions from supervisor.

Storage ∇

Storage occurs when the object is kept in an authorised custody and is protected against

unauthorised removal. For example, materials kept in stores to be distributed to various work.

ILLUSTRATION 1. Develop a Process Chart for making a cheese sandwich.

SOLUTION. The following chart is one possible solution. The level of detail in process

charts depends upon the requirements of the job. Time is often included to aid analysis of value

Reliability centered maintenance: Reliability centered maintenance (RCM) is defined as “a

process used to determine the maintenance requirements of any physical asset in its operating

context”.

Basically, RCM methodology deals with some key issues not dealt with by other maintenance

programs. It recognizes that all equipment in a facility is not of equal importance to either the

process or facility safety. It recognizes that equipment design and operation differs and that

different equipment will have a higher probability to undergo failures from different degradation

mechanisms than others. It also approaches the structuring of a maintenance program recognizing

that a facility does not have unlimited financial and personnel resources and that the use of both

need to be prioritized and optimized. In a nutshell, RCM is a systematic approach to evaluate a

facility’s equipment and resources to best mate the two and result in a high degree of facility

reliability and cost-effectiveness.

RCM is highly reliant on predictive maintenance but also recognizes that maintenance

activities on equipment that is inexpensive and unimportant to facility reliability may best be lef

top-performing facilities would echo the RCM approach to utilize all available maintenance

approaches with the predominant methodology being predictive.

<10% Reactive

25% to 35% Preventive

45% to 55% Predictive.

Because RCM is so heavily weighted in utilization of predictive maintenance technologies,

its program advantages and disadvantages mirror those of predictive maintenance. In addition to

these advantages, RCM will allow a facility to more closely match resources to needs while

improving reliability and decreasing cost.

Advantages

(a) Can be the most efficient maintenance program.

(b) Lower costs by eliminating unnecessary maintenance or overhauls.

(c) Minimize frequency of overhauls.

(d) Reduced probability of sudden equipment failures.

(e) Able to focus maintenance activities on critical components.

(f) Increased component reliability.

(g) Incorporates root cause analysis.

Disadvantages

(a) Can have significant startup cost, training, equipment, etc.

(b) Savings potential not readily seen by management.

How to Initiate Reliability Centered Maintenance?

The road from a purely reactive program to a RCM program is not an easy one. The following

is a list of some basic steps that will help to get moving down this path.

1. Develop a master equipment list identifying the equipment in your facility.

2. Prioritize the listed components based on importance to process.

3. Assign components into logical groupings.

4. Determine the type and number of maintenance activities required and periodicity using:

Manufacturer technical manuals

Machinery history

Root cause analysis findings—Why did it fail?

Good engineering judgment

5. Assess the size of maintenance staff.

6. Identify tasks that may be performed by operations maintenance personnel.

7. Analyze equipment failure modes and effects.

8. Identify effective maintenance tasks or mitigation strategies