SPARES CRITICALITY ASSESSMENT METHOD

Group Members

Kelvin Lazarus

Kong Chiou Shin

Loh Vuan Yee

Hou Xiao Ming

What are Spares Parts

Spare parts are extra parts that are near to a functioning part

When a machine has problems, spare parts can be used to replace broken /damaged parts so that the machine can function.

Example :- power module (eg. Transformer) Electronic parts (eg. Integrated components /

semi-conductors and etc.

What is Criticality Assessment Give an indication of which items of

plant are most critical to your process. Good idea to do a criticality assessment

so everybody involved on your plant knows how crucial any single item of plant is to the process and how quickly to act when diagnosed an impending failure.

What is Spare Criticality Assessment

Spare Critically Assessment plays an important role in achieving the desired plant availability at an optimum cost

Downtime for such plant and machinery is prohibitively expensive

It has been observed in many industries that the non-availability of spare parts, as and when required for repairs, contributes to as much as 50% of the total down time

Classification of Spare Parts

1. Critical spares without which the machine can’t be operated even in

suboptimal efficiency with a high failure rate with long procurement lead time without a substitute used in critical machines (identified for preventive

maintenance)

2. Non critical spares without which machine can run (at least sub optimally) that have high reliability that can be made / purchased in short notice that have substitutes available off shelf as standard parts (bearings etc.)

Models for Type of Spares

Non-repairable Spares

Parts which fail can’t be repaired and must be replaced with a new parts

Models for Type of Spares

Repairable Spares

Parts which fail can be repaired and be used back as spares

Assessment Method

Analytic hierarchy process find out relevant factors of the critical spare parts

and determine the relative importance Grey prediction model

find a sequence of each element corresponding to future dynamism, thereby developing prediction model

Back-propagation network used as a tool for judging the predictability

Moving average method The moving average (MA) is the mean of the

previous data sets used to perform CSP demand prediction

Assessment Method

Management of Spare Parts

Proper planning and control of spare parts inventory.

Eg: Material forecast planning, Asset recovery services, Equipment receiving and staging, Equipment tracking and reporting.

How To Manage Spare Parts

1. Identify requirement Standard procedures and relevant

documentation is obtained Current holdings are monitored and

checked against levels determined by procedures

Each holding location is checked as to needs

How To Manage Spare Parts

2. Procure parts Current holdings are matched with need Requests for additional parts are made in

accordance with enterprise procedures Checks are made as to extra holdings in

other locations

How To Manage Spare Parts

3. Initiate replacement process Need for spare parts is determined Data base is activated to check possible

location of specific parts required Arrangements are put in place to deploy the

part to the site where it is required Part is changed over with the faulty part Faulty part is recovered and disposed of or

returned for repair as determined by condition and enterprise policy

How To Manage Spare Parts

4. Reorder part replacements Relevant part request

(forms/documentation) is completed and forwarded to the vendor

Delivery of replacement is followed up on a regular and ongoing basis (eg: phone call)

Alternate spares are sought where difficulties (delay/no stock) are experienced with replacement

How To Manage Spare Parts

5. Complete administrative tasks Relevant documentation is completed,

signed and forwarded to the appropriate area (eg: Account Payable - Boucher, Account Receivable – receiving documentation, Filing and Retention document – filing history)

Regular audit of stock holdings is conducted in accordance with enterprise policy

Checks are made to ensure that all parts are latest issue and are compatible with installed systems and equipment

Inventory

Inventory is the total amount of goods and/or materials contained in a store or factory at any given time.

Helps us know the precise number of items on the shelves and storage areas in order to place orders or control losses

Inventory Analysis

Commonly used inventory analyses are: (1) FSN Analysis (2) HML Analysis (3) VED Analysis

Inventory Analysis

FSN Analysis Fast Moving (F) = Items that are frequently

issued say more than once a month. Slow Moving (S) = Items that are issued less

than once a month Non-Moving (N) = Items that are not issued\

used for more than 2 years. Help establishing most suitable stores

layout by locating all the fast moving items near the dispensing window to reduce the handling efforts

Inventory Analysis

HML Analysis High Cost (H) : Item whose unit value is

very high Medium Cost (M) : Item whose unit value is

of medium value Low Cost (L) : Item whose unit value is low

Efforts may be necessary to find out the means for prolonging the life of high value parts through reconditioning and repair

Inventory Analysis

VED Analysis VITAL (V) : A spare part will be termed vital, if on account of its

non-availability there will be very high loss due to production downtime and/or a very high cost will be involved if the part is procured on emergency basis. In a process industry, most spare parts for the bottleneck machine or process will be of vital nature.For example, bearings for a kiln in a cement plant will be considered vital.

ESSENTIAL (E) : A spare part will be considered essential if, due to its non-availability, moderate loss is incurred. For example, bearings for motors of auxiliary pumps will be classified as essential.

DESIRABLE (D) : A spare part will be desirable if the production loss is not very significant due to its non-availability. Most of the parts will fall under this category. For example, gaskets for piping connection.

The End