Presentation1 709

8/8/2019 Presentation1 709

1/18

TEC-709 MAINTENANCEENGINEERING

Introduction to

Maintenance Engineering


2/18

Introductiony The Oxford dictionary meaning of to maintain is to

cause something to continue or to keep

something in existence at the same level.

y Maintenance is the process of maintaining an itemin an operational state by either preventing a

transition to a failed state or by restoring it to anoperational state following failure


3/18

IntroductionyMaintenance engineering is typically

defined as a staff function whose prime

responsibility is to ensure thatmaintenance techniques are effective,equipment is designed and modified to

improve maintainability, ongoingmaintenance technical problems areinvestigated, and appropriate correctiveand improvement actions are taken.


4/18

Purpose of MaintenanceyThe purpose of maintenance is to produce

reliable plant capacity. The company vision

for producing a profitable product shouldunderstand that effective maintenanceprovides reliable plant capacity. Some of

the most important maintenance decisionsare made before a company even builds aplant.


5/18

Purpose of MaintenanceyGifford Brown (1993) of Ford Motor

Company explains the 1-10-100 Rule. This

rule means that every $1 spent up frontduring engineering to reduce maintenanceeliminates a later $10 cost to maintain

equipment properly or $100 in breakdownmaintenance.


6/18

Purpose of Maintenancey It means that every company has to maintain operable with

due efficiency and effectiveness of its fixed assets.Encompasses all activities necessary for:

- Maintain a facility or equipment in operation

-Reset the operation of equipment to original condition.

The maintenance impact, therefore, the quantity and quality ofproduction.

Indeed, the amount of production to a given quality level isdetermined by the installed capacity and its availability,meaning that the ratio of the effective time of productionbetween this and the amount of downtime for maintenance.


7/18

Responsibility of the Maintenancey The principal responsibility of maintenance is to provide a service to

enable an organization to achieve its objectives. The specificresponsibilities vary from one organization to another; however they

generally include the following according to Duffuaa et al. (1998):

y 1. Keeping assets and equipment in good condition, wellconfigured and safe to perform their intended functions;

y 2. Perform all maintenance activities including preventive,

predictive; corrective, overhauls, design modification andemergency maintenance in an efficient and effective manner;

y 3. Conserve and control the use of spare parts and material;

y 4. Commission new plants and plant expansions; and

y 5. Operate utilities and conserve energy and environment.


8/18

Maintenance PhilosophyyBased on the timing and the work

contents involved in the maintenancetask, different maintenancephilosophies can be put in thefollowing categories, viz.:


9/18

Maintenance Philosophyy1. Timing known, content known:

preplanned maintenance (PPM),planned shutdowns, routineinspections, and scheduled change-outs fall in this category;


10/18

Maintenance Philosophyy2. Timing known, content unknown:

statutory surveys, third partyinspections, and condition-basedmaintenance;


11/18

Maintenance Philosophyy3. Timing unknown, content known:

anticipated maintenance work,contingency work awaiting shutdown,and run to destruction; and


12/18

Maintenance Philosophyy4. Timing unknown, content unknown:

break-down maintenance, immediaterepairs arising from inspection, andrun to failure.


13/18

Maintenance Scope Changed with Timey In recent times, there has been tremendous growth in

maintenance concepts and techniques. The change inemphasis includes:y Decision support tools, such as hazard studies, failure

modes and effects analyses, and expert systems.

y New maintenance techniques such as conditionmonitoring or CMMS.

y

Designing equipment with emphasis on reliability andmaintainability.

y A major shift in organizational thinking towardsparticipation, teamwork and flexibility.


14/18

Approaches to Maintenancey There are several approaches to maintenance,

and different approaches are applicable based

on the expected use and maintenance scheduleof an item.

y Economic considerations are tightly related to

maintenance and the system lifecycle; it is clearthat failure to consider a designs effects onmaintenance, and vice versa, can have adverseeffects on profit.


15/18

Approaches to Maintenance

y Maintenance has been categorized based on the

nature and purpose of the maintenance work andon its frequency. Generally, there are four(basic)types of maintenances in use, viz., preventive,corrective, predictive, and fault-finding.


16/18

Approaches to Maintenancey Maintenance can also be classified according to

the degree to which the maintenance work is

carried out to restore the equipment relative to itsoriginal state. This leads to the followingcategorization:

y Perfect maintenance is maintenance which restoresthe equipment to as good as new condition.


17/18

Approaches to Maintenancey Minimal maintenance results in equipment having the

same failure rate as it had before the maintenanceaction was initiated. This is also called the as bad asold state.

y Imperfect maintenance is maintenance in which theequipment is not restored to as good as new, but to a

relatively younger state (a state in between as good asnew and as bad as old).


18/18

Approaches to Maintenancey Worse maintenance: This type of maintenance results

(unintentionally) in an increase of the equipmentsfailure rate or actual age but does not result inbreakdown.

y Worst maintenance: This type of maintenance results(unintentionally) in the equipments breakdown.

Presentation1 709

Documents