Well-established and well-understood procedures for getting, returning, and accounting for maintenance materials.
4. Inventory on shelf for one year or more. | 5. Craftspeople can identify and obtain parts without supervision’s authorization. | 5. Inventory cannot be reconciled. |
6. Little hoarding of parts by craftspeople. | 6. Parts can be added to or taken from inventory without proper paperwork or computer entry. |
7. Quick and well-defined withdrawal procedures even after stores hours (where storeroom is not open as many hours as maintenance works). | 7. Slow parts window. |
8. Requirement that all parts removed are recorded on work orders or an equivalent document. | 8. Hoarding of parts by craftspeople. |
9. All parts must be received, priced, and physically checked, counted, and signed for. | 9. Inflexible and hard-to-use computer system for inquiry and research. |
10. Periodically and randomly sample the waiting time at the counter for parts — work to reduce it. | 10. Purchase orders issued after item was received. |
11. All parts are assigned locations. | 11. Items are routinely purchased with petty cash on a rush basis. |
12. Periodic physical inventories are taken to verify quantity and location. | 12. Little knowledge of location, inventory level, usage. |
13. Some means for recording usage, price history, where used, and substitutions. | 13. No established min/max, reorder points, EOQs. |
14. Periodically shop for parts and evaluate vendors. | 14. No competitive bids or sweetheart deals with certain vendors (not partnerships). |
15. Nothing gets added to stock without stores team approval. | 15. Parts purchased but never used, no accountability of parts used. |
16. Periodically review applications and specifications of parts. | 16. No attempt to help craftspeople by pre-kitting work. |
17. Periodically review part usage and lead time to adjust min/max and economical order quantity (EOQ). | 17. No proper storage; unlimited access to parts room. |
18. If you don’t use it, don’t stock it. | 18. No physical inventory taken. |
19. Divide parts into classes for different treatment. | 19. Excessive hoarding of parts by mechanics outside of the parts room. |
20. Be sure new assets have parts requirements developed before they are needed. | 20. No knowledge of the current value of the inventory. |
21. No field re-engineering (without documentation). | 21. No analysis of the current value of the inventory. |
22. Parts for retired assets are reviewed for use elsewhere or disposed. | 22. Tough to find parts by descriptions or by where used. |
23. Be sure broken, bad, or ruined parts are disposed of promptly. | 23. Different reference numbers in different storerooms. |
24. Have an area for incoming and outgoing rebuildables. | 24. No knowledge of quantity on hand at the moment. |
25. Parts for PM and other routine jobs are entered on a bill of materials and pulled together as a kit. | 25. Multiple vendors make it hard to keep track of cost. |
26. Job material requirements are transmitted to the storeroom in advance of the job (by the planner or supervisor) when the job is firmly slotted to begin. | 26. Constant calls to vendors for emergency drop-offs. |
27. Don’t run out of toilet paper! | 27. Field re-engineering changes parts needed without changing bill of materials. |
| 28. Bad relationships among stores, maintenance, and purchasing. |
| |
| Bonus Symptoms: |
| 29. Craftspeople rely on supervisors to get them materials. |
| 30. Craftspeople rely on planners to get materials. |
| 31.Craftspeople rely on superintendents to get them materials. |
• In stock, but can’t be found
• In stock but misidentified
• Not in stock and shouldn’t be, but no one knew that
Findings From Some Experts
The authors of Production Spare Parts (Moncrief et al.) list their conclusions from 25 years advising maintenance stockrooms in a variety of industries. Although these conclusions are not “truths,” they are items to watch for.
• 80–90% of the SKUs in the warehouse are rarely used.
• 40–45% of the SKUs have overstock.
• Only 50% of the overstocks will be used up within four years if they are not reordered.
• 40% of the overstocks are first-time buys.
• About 70% of initial buys are high, 10% are low, and 20% are okay.
• Lower cost items are ten times more likely to be overstocked.
• Items with longer lead times are more likely to be understocked.
• Vendor partnering can reduce stock levels by 20–30%
• Pareto analysis works great with inventories.
• Sharing spares with other plants can reduce stock by 20–35%.
• Shorter lead times can reduce stock by 20–30%.
CHAPTER 5
HOW WELL DO YOU KNOW YOUR CURRENT STORES OPERATION?
There are a lot of interesting facts about maintenance and your storeroom that you should know in order to evaluate current performance and opportunities for improvement. Table 5.1 lists many of these facts.
Table 5.1: Learning About Maintenance and Your Storeroom
RAV (replacement asset value) of all assets in plant that the storeroom supports, including buildings and rolling stock |
Inventory Value / RAV |
Number of Work Orders completed per day |
Average number of window visits per day |
Number of SKUs (line items in inventory) |
Value of inventory to support maintenance |
Annual turns: Annual consumption / Value of inventory |
Number of shipments the storeroom receives each month |
Service level each month = Number of requests satisfied / Number of parts requests that month |
Work Order service level each month = Number of Work Orders with all parts / Number of Work Orders with parts that month |
HOW TO EVALUATE YOUR STOREROOM IN AN HOUR (OR TWO)
• Look closely at a bunch of bins in the storeroom.
See if any have more than one type of part.
Randomly sample four or five bins. Compare the count to your ERP or CMMS inventory record.
Write down a few bins that are empty.
Check the system see if any are showing a positive QOH (quantity on hand).
Check to see they are on reorder and are expected soon.
• Look at the number of stock outs per month and especially the number of stock outs of important parts causing downtime.
• Take a random sample of waiting time (at the parts window), reporting the average and standard deviation.
• Do you have a storage area for urgent parts? If so, note the dates they arrived. Subtract the arrival dates from the current date to see the number of days the packages have been there.
• How many parts did not move at all in the last year? Of these parts, which ones are not on the critical or insurance policy parts lists?
• Are the basics numbers of the warehouse (well) known: value of stock (by category), number of SKUs, turnover, accuracy, etc.?
• Finally, talk