What Spare Parts Should Your Order Fulfillment Operation Always Have on Hand? 4 Considerations
From sorters, to automatic storage and retrieval (AS/RS) to conveyors, AGVs, AMRs, and more, if your operation utilizes any kind of automated or even semi-automated technology or equipment, then you know just how important those systems are to the success of your business. If any of those systems were to experience unplanned downtime, it could be catastrophic to your bottom line.
That’s why it is so critical to ensure that you always have a well-stocked supply of spare parts and components for your systems.
Some operations will go to an extreme and stock every possible spare part necessary for their equipment so that they always have the part necessary to keep their systems running smoothly. But for other operations, there may be a lack of capital (or a desire to put that capital to better use elsewhere in the business) that makes such thorough stocking impossible. Even in those cases, though, there is a bare minimum level of spare parts that should be kept on hand.
While the exact spare parts that you should stock in your operation will depend on the specific technologies and equipment that you utilize, below we discuss some key considerations that you can use to decide exactly which parts should be prioritized.
1. Is the equipment essential to your operation?
For any equipment that is critical to the success of your operation, you should have fully stocked spare parts. If you don’t, and the worst case scenario were to happen and the equipment went down unexpectedly, your operation could potentially grind to a screeching halt.
One example of such equipment that applies to many operations would be a conveyor or sorter that acts as a consolidation area in the heart of your operation where multiple lines merge. If a system on the outskirts of your operation were to experience a failure or need a repair, it’s possible that you could limp along by rerouting product elsewhere in the system. This is next to impossible to do when you’re talking about equipment in the heart of your operation.
In short, if a single piece of equipment touches a large percentage (or all) of your orders or product, that system needs to be supported with spare parts. We often refer to this as “mission critical” equipment or systems.
2. Does the equipment or support multiple areas of your operation?
In most modern operations there are certain pieces of equipment that support multiple systems or processes. Just as with the essential equipment discussed above, if this equipment was to experience a malfunction or a failure, it could potentially take down large swaths of your operation. Even if it is unlikely that this equipment will fail, it may be a good idea for you to have at least some spare parts on hand to support this equipment.
One example of such a piece of equipment is a programmable logic controller (PLC). Though these are designed to last for a very long time, it can be difficult to predict when they may fail. Because the impact of such a failure is so large, it would be wise to have a spare on hand just in case.
3. Does the equipment have parts that are specific to it?
In many cases, spare parts can be put to use in support of a range of equipment and systems, even if they are not necessarily designed for a particular system.
This is particularly true for many wear components like belts, chains, and sprockets. If a belt in your sorter were to split or tear, for example, it is likely that a spare belt for another piece of equipment could make do until a proper replacement was ordered and found.
But for each type of technology and equipment you employ in your system, there are likely to be specific parts or components that can not easily be swapped between machines. These components should be well-stocked just in case of emergencies.
For example, motors and gearboxes tend to be equipment-specific, and both are critical to a piece of equipment running. If a motor fails or a gearbox seizes up, the system can’t run and the operation grinds to a halt.
That being said, a well-designed system should aim to create commonalities between different pieces of equipment—for example, by using only 3 different types of motor throughout the entire operation. This will allow an operation to stock fewer types of spare parts, because those parts can support multiple technologies.
4. Are the parts difficult to source?
Certain parts and equipment components are so common that they are stocked all across the United States. They’re sold and stocked by multiple vendors, in multiple locations, and can generally be sourced in the event of a breakdown or failure. While of course it’s better to have parts readily available to address an issue the moment that it happens, for these more easily sourced spare parts it isn’t always necessary to stock them on site.
On the other hand, other parts can be more difficult to source. Maybe they’re supplied by a single vendor or company. Maybe they’re sourced from overseas and aren’t readily available domestically. Maybe they are custom-built. Whatever the case, it can take some time for these parts to be delivered—up to a month in some extreme cases.
For any operation dependent on hard-to-source parts, it’s generally a good idea to have those parts on hand in case of emergency. If not, and your equipment were to fail, you risk your operation being down for a long period of time. Even if it is not completely down, it may be forced to run at a less-than-optimal capacity or speed, impacting your profits and bottom line.
It’s all about managing risk
Managing spare parts is ultimately all about managing risk. While risk may seem like an abstract concept, it’s actually very easily summed up by the equation below:
Risk = Chance x Effect
As a rule of thumb, the riskiest parts are those that are almost guaranteed to eventually fail (typically, wear parts) that have a high impact on the machine they support. These are the parts that you should absolutely stock. The least risky are those that are very unlikely to fail, as well as those that would have a minimal impact if they do fail. These parts you can probably do fine not stocking on site.
For everything in the middle, keeping the considerations outlined above in mind can help you determine which spare parts it makes sense for your operation to invest in.
