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Materials sine qua non


Do you have spare parts laying around for machinery or equipment that is no longer in service? Of the material items that are available, are they useable or reliable? In short, do you really need them and if not, why are you keeping them?

Although these questions sound simple in nature, they are often overlooked in industry. But wait, there's more.........

What material items have you deemed as essential? Of these, which material items can be discarded?

With no surprise, the quick answers are always a resounding "all of them" and "none of them." So you may ask, "If it is an essential material item, why discard it?" At one time, the general consensus might have been: Those material items are all deemed as necessary and essential or we wouldn't have them to begin with. Ultimately, this practice over time leads to a collection of duplicate, overstocked, obsolete and eventually, orphaned items.

Sine Quo Non

In a recent material reorganization project to help bring about sine quo non (an essential part of the whole) in support of opportunities to improve reliability, several hurdles had to be overcome. The first of many hurdles was to moderate and control the unnecessary collection of material items that were obsolete, deteriorated, non-repairable and/or just unidentified. The conundrum of "hoarding" was (at no surprise) rampant with unaccounted for stock squirreled and strewn throughout the site. Worse yet was evidence of cannibalized equipment/material/ parts salted away in and sometimes under material "bone yards." Obviously, this proves to be a compounding problem. Proper attention devoted towards realizing when a material item's necessary expiration date has arrived was long past due (no pun intended).

Definition of ESSENTIAL: of the utmost importance - basic, indispensable and NECESSARY.

Clean House

To tackle this impediment, a campaign called Operation Red Rampage was initiated, with a follow-up campaign of Operation Green. Here, red signifies discard and green signifies a material item's return to stock (RTS) or simply capturing the material as a non-stock item for location purposes within the computerized maintenance management system (CMMS). The sole reason for the red rampage campaign was to identify excess material items that are questionable in terms of use, utilization and reliability. These material items were in need of discard to make room for needed items.

In order to fast-track the material reorganization project, the metrics of "essential" and/or "necessary" were inclusionary measurements that determined whether or not a material item was a candidate for discard. The following questions were utilized to help identify which material items were not a discard candidate, but more importantly, what material items were ready for discard.

Discard Criteria

  1. Criticality of Importance
  2. Identity of Use
  3. Availability
  4. Restore
  5. Locality of Use

Criticality of Importance:
Criticality can be defined as being crucial to the business and requires a decisive decision. Applied to the potential discard of a material item, the importance and relevance of the item had to be closely examined to make a decisive decision as to its validity and/or need. In other words, the item may be obsolete and therefore not needed. Or the item is deemed critical and can be reliably used (either through reconditioning or in its current state), so it is not a candidate for discard.

If a material item's criticality is not immediately decisive, the next two inclusionary measurements can help to determine its criticality of importance.

Identity of Use:
Identity of Use can be defined as a process where a material item has a defined role or use. It is here where the answer to "what" and/ or "where" the utilization of the material item is determined.

Is the item used on a critical asset or assembly? If so, the material item is deemed critical and is not a candidate for discard. But with a "no" answer, the material item can be a potential candidate for discard. Simply put, if we do not know where or what the material item is utilized for, we don't need it.

Availability is, in other words, lead time to acquisition.

What is the amount of time it would take to replace the material item in the cases of run to failure (RTF), just in time (JIT), or planned maintenance scenarios?

The material item may or may not be of critical nature, but the lead time to replace the material item may be in excess of multiple weeks or even months. In this case, the material item could be listed as a critical spare in your EAM/ CMMS. Best practice here is being proactive with the use of your ERP system in replacing the critical spare item upon its initial need.

From a discard perspective, the questions to ask are: How many of the items do I reliably need on hand? What is an appropriate number of items to be stocked based on average turnaround time? Is it admissible to have only one critical spare on hand? What is the shelf life versus the average turn of the material item? Has it expired?

Can the material item be reconditioned back to its original "like-new" condition? If not, discard. With this criterion, a material item may or may not be classified as critical, but the cost of replacing the item far outweighs the restoration cost. If this is true, the material item should be discarded before it can be mistakenly used, or worse yet, used again.

Locality of Use:
Up until now, an item's decision for discard can be justified during any of the above means. But with Locality of Use, or simply put, logistics, the decision to not discard the material item can be based on where the material item is located in respect to the equipment it serves. Consider the case where the nearest material store is not close by or the equipment is located in a remote area of a site.

The qualifying question of, "where is the most efficient yet reliable storage area with regards to the location of the asset it supports?" becomes, in and of itself, necessary to the uptime of the machinery. The material item may not be critical or has a short availability factor, but it has been deemed as essential based on logistics.

From a discard perspective, if the location of the material item does not carry a logistical value, it can then become a discard candidate.

figure 1

Figure 1: Sampling of discarded items

The Collection

At the conclusion of Operation Red Rampage, an excess of 489 metric tons of scrap metal parts/pieces/material items were collected. It involved looking back over multiple decades of various obsolete parts, materials, discarded equipment (both in asset and support types) to account for such a collection of scrap metal. In addition to the investment recovery from scrap material as an added benefit, the move to abrogate excess, inferior and duplicate material items will prove in the long run to help and support the sine qua non of achieving sustainable yet reliable materials management best practices. Perhaps it's time to start your own Operation Red Rampage.

authorGreg Perry is a consultant with People and Processes, Inc. He has over 12 years experience specializing in work process improvements, Preventive Maintenance (PM) development, Materials Management, and CMMS (Computer Maintenance Management System) implementations.

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