Don’t fear the unknown

Here are some sure-fire ways to reduce not-so-obvious storeroom risks

by Ricky Smith

MRO storeroom practices are the root cause of a significant number of equipment reliability problems.

Problems generally aren’t the result of a “non-dedicated” or “incompetent” storeroom staff. They usually occur from a lack of maintenance support and management focus, and an ineffective operating process.

What are the risks associated with bad storeroom practices? Of course, there are the obvious: stockouts of critical spares, wrong parts delivered and stored under valid part numbers, etc. But what about not-so-obvious risks? These are perhaps more insidious because you don’t know where these risks are and you don’t know your risk level.

Common “unknown” risk factors related to storeroom practices are:

Used parts: These can and do represent a high rate of failure because their reliability life is unknown. A used part could last two minutes or two years. Can you accept this risk?

Parts not “installation ready” for equipment repair:  For example, motors with rusted or nicked shafts can cause a mechanic, pressed to get equipment back on line, to install a coupling with a hammer, resulting in premature motor failure.

No preventive maintenance (PM) coverage on appropriate storeroom parts: These parts can include large gearboxes, motors and bearings. PMs can be as simple as inspecting protective packaging or taking preservation measures.

Unknown shelf life and/or storage specifications: Examples include storing electrical components in a dusty or humid environment and checking out conveyor belting after it surpassed its 12-month shelf life.

Parts used but not logged or drawn on a work order: This unknown becomes apparent the next time that part is needed. The part’s not available because nothing generated a reorder.

Unrestricted use of consumables (e.g., lubricants): This creates an unknown through a lack of usage data and the failure to trigger a low-level automatic reorder point.

Ineffective parts locator system: This creates lost time spent hunting through the storeroom for a part. This waiting can result in production line downtime. It could also result in a mechanic using a “close enough” part and thus changing the specifications and reliability of a piece of equipment.

The first step
To eliminate these risk factors, incorporate these tips into your storeroom practices:
• Identify and track the storage requirements and shelf-life limits on applicable spares.
• Have vendors that rebuild your motors, gearboxes, etc., return the item in a “ready to install” state; perform receipt inspections.
• Extend your PM program to specified spares that need attention at defined intervals. Ask your vendors for PM procedures and frequency.
• Continuously update equipment inventory lists and associated repair parts listings. This should cover the purging of removed items.
• Identify/associate all storeroom inventory with its equipment application (based on the updated plant equipment inventory list).
• Establish a “parts for work order process” (no part is issued without a work order).
• Establish a barcode system for the storeroom that identifies part, equipment application and storeroom location.
• Establish and enforce the use of a log sheet for all “after hours” parts and consumables usage.
• Facilitate parts consolidation by establishing proper stocking levels and assigning minimum and maximum levels for each item.
• Work with individuals to eliminate private “parts stockpiles.” The condition of these parts is unknown. The parts also generate no usage data, which eventually results in stockouts.
• Track premature failure of equipment/parts taken from stores inventory (strive for less than 0.1 percent) and stockouts (less than 2 percent). Perform cycle counts at a set time interval (seek better than 98 percent inventory accuracy).
• Visit all rebuild operations to ensure they have your best interests in mind.

For the common good, maintenance and stores management must work together because each helps define storeroom practices. Maintenance management must provide clear direction to its staff for assistance in eliminating stores problems. The bottom line is that all parts leaving the storeroom must be able to provide maximum reliability, not provide equipment with unacceptable reliability risks.

The next step
When your plant’s operation matures, one step can eliminate almost all of your “unknown” storeroom risk factors: Shift as much of the stores’ risk burden to your suppliers as practical.

This is pretty simple and is based on just-in-time supply management. To be successful, though, your plant must have a Computerized Maintenance Management System (CMMS) that is installed, implemented and fully integrated between maintenance, purchasing and the MRO storeroom.

In the past, one of the maintenance storeroom’s objectives was to carry as many spare parts as possible, just in case they were needed. But the increasing cost of inventory makes that practice obsolete. Eliminate more than half of your existing inventory by using your CMMS to schedule (based on maintenance action scheduling) when you need repair parts and consumables. Your supplier then receives specific delivery requirements to meet those maintenance schedules (JIT delivery). All PM-related parts and consumables can be removed from your storeroom. Incoming items can go directly to a staging area (much smaller than the storeroom space previously occupied) for issue to the following week’s PM work orders.

Accurate equipment inventories in your CMMS aid in accurately identifying repair parts requirements. By providing these requirements to your supplier, you can contract for minimum lead time delivery (JIT) of those parts. Now, instead of carrying sufficient parts for six months’ usage, minimum lead times (for example, one week) allow you to reduce that level to one week’s usage. You achieve a 26-to-1 reduction in on-hand parts inventory.

Your CMMS can also supply you with application data for repair parts. If a part is used in six different machines, you don’t need to keep six parts in your spares inventory. Two is more than ample. And with minimum lead time ordering, you could probably reduce that item in inventory to one. A reduction here is as much as 6-to-1.

Predictive maintenance (PdM) measures equipment condition-related data (vibration levels, temperature, oil viscosity, speed, etc.) that can be trended by your CMMS to predict when equipment will exceed its operating specifications. Use these predictions to trigger repair parts ordering based on procurement lead time and predicted out-of-tolerance condition.

The CMMS can generate parts usage data that should be used to reorganize your storeroom. Make high-usage items quickly accessible; low-usage items go to the back of the storeroom. A word of caution, though: All parts locations (high or low usage) must be accurately identified. Accessibility means the time it takes to walk directly to the part’s location, not how long it takes to hunt the part down.

Also, use the CMMS to enter and retrieve parts location information (you can greatly enhance this by using bar-coding).

Final words of wisdom
The previous paragraphs discussed CMMS utilization to reduce storeroom inventory and increase efficiency. Having a CMMS does not automatically accomplish these efficiencies; rather, a CMMS is a prerequisite to MRO storerooms implementing these processes. It is the practice, not the CMMS, that facilitates inventory reduction and improved storeroom efficiency. s

Ricky Smith is the executive director of maintenance solutions for Life Cycle Engineering. To learn more, call , ext. 350, or e-mail .

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