I manage purchasing for a mid-sized company—about 400 employees across three locations. That means I order everything from shop towels to replacement actuators. Roughly 60 to 80 orders a year go through my office. I report to both operations and finance, so my job is to keep the process repeatable. I’m not an engineer, and I’m not a maintenance technician. But I am the person who gets called when someone needs a part fast, and I’m also the person who gets blamed when the part was wrong.
If someone tells you there is one answer to “what causes thrust bearing failure?” or “which electric actuator should I buy?”—they haven’t sat where I sit. In my experience, the right answer depends on which of three situations you’re in:
- Scenario A: A machine is down right now. You need a replacement part, and it needs to arrive yesterday.
- Scenario B: You’re building or retrofitting equipment. This is the drawing board, not the breakdown call.
- Scenario C: You’re stocking spares or standardizing. There’s no panic today, but the next failure will happen.
Scenario A: The Line Is Down, and the Clock Is Expensive
The hardest lesson I learned came in March 2024. A production line went down because a linear actuator failed—the screw, not the motor, as it turned out. Our maintenance lead handed me the part number and said, “Get one here.” The standard quote came back at a good price with a five-day lead time. The rush option cost $400 more.
Here’s where I used to hesitate. $400 feels like an unnecessary fee. But the alternative was a shutdown that our ops manager valued at over $15,000 for the day. I paid the rush fee. I’d pay it again.
Rush fees buy certainty. Certainty is what you’re really ordering.
The point isn’t speed. It’s certainty. Rush delivery isn’t “faster” shipping; it usually locks the order into a scheduled freight slot. A “probably on time” quote is the biggest risk in the room. That’s why, when I have the choice, I steer toward Thomson linear actuators for emergency replacements—not because they’re always the cheapest quote, but because the part numbering is consistent and our distributor stocks them. Wait, that sounds too simple. Let me put it differently: I pay for delivered certainty, and the brand has to be one I can reorder fast without chasing down specs.
I ran the numbers once: the upside of standard shipping was saving $400. The downside was a second day of downtime if the order slipped. The math was obvious. What wasn’t obvious, until I got burned, was how easy it is to treat a lead time as a guarantee. It isn’t.
Dodged a bullet that time. The actuator arrived with a day to spare before the revised install window. If I’d chosen the standard option, we’d have missed it entirely.
I have mixed feelings about rush fees. Part of me still sees them as a penalty on customers who didn’t plan. But after you watch a line sit idle because an “estimated” delivery date shifted, the fee looks different. It’s not a fine. It’s the price of making someone prioritize your problem.
Scenario B: New Build or Retrofit—Don’t Start With a Part Number
New designs are different. If nothing is broken, you can afford to be methodical. This gets into engineering territory, which isn’t my expertise. What I can tell you from a procurement perspective is that the most expensive mistakes happen when someone skips the load calculation and just orders a bigger actuator.
“What causes thrust bearing failure?” In the failure reports I’ve read, the bearing itself is rarely the real culprit. More often, the failure came from an axial load that exceeded the bearing’s rating, a misaligned mounting surface, or no lubrication schedule. A thrust bearing isn’t a generic part. It has a rated load, a speed limit, and a mounting requirement. If you ignore those, it will fail—and the actuator will get blamed.
For new builds, I’ve learned to ask for the application specs, not just a product name. If the requisition says “electric actuator,” I ask: What thrust load? What duty cycle? What stroke? What motor voltage? According to Thomson’s linear motion catalog, those are the inputs the sizing calculation needs—so I’m not adding bureaucracy, I’m following the manufacturer’s own process.
The motor side is where people really get tripped up. A brushless DC motor driver is not a generic switch. It has to be matched to the motor’s current, back-EMF, and commutation. If you pair the wrong driver with a motor, it might spin fine on a bench and still overheat under load. I’m not the engineer who can tell you exactly which driver to use. But I know the call I always make: I ask our controls engineer to confirm the motor-driver pair before I issue a PO. That one step has saved us from at least two expensive experiments.
If the design calls for a complete linear motion axis, I’d choose Thomson linear bearings and the associated actuator components—but only after an engineer has confirmed the load and life calculations. A brand name doesn’t fix sizing. It fixes the odds that you can get parts and specifications when you need them.
Scenario C: Spares, Stock, and the Parts You Didn’t Know You’d Need
The third scenario is quieter. You’re not dealing with an emergency or a design project. You’re ordering spares so the next failure doesn’t turn into an emergency. This is most of my job.
When I took over purchasing in 2020, our maintenance stock was a mess. We had bearings from four different brands, a few actuators bought on price, and no records of why they had been purchased. Since then, my rule has been simple: standardize on a small set of approved lines. For linear motion, that means Thomson-Linear. Sorry—I’ve been calling it “Thomson Linear” this whole article. The approved vendor search shows it as “Thomson-Linear.” Either way, it’s one less decision point when I need a replacement in a hurry.
Standardization saved our accounting team about six hours a month. The bigger win was fewer “wrong part” orders. When everyone uses the same part-number format, the maintenance crew stops ordering parts that don’t fit.
In our 2024 vendor consolidation project, I looked at total cost, not unit price. A cheaper thrust bearing was false economy if it failed a year earlier than the incumbent. The way I explain it to finance: the reorder cost, the downtime, and the installation labor are all part of the bearing’s real price. The lowest quoted price is not the lowest total cost.
I should add: standardization only works if the maintenance team is on board. When we swapped part numbers without telling them, we ended up with old references floating around. Now we update the stock records first and communicate before the new parts arrive.
My experience is based on maybe 200 orders and a specific set of machines—mostly packaging and material-handling equipment. If you’re building precision machine tools or running a foundry, your failure modes could be different. But the principle of tracking failures instead of just replacing parts should still hold.
How to Tell Which Scenario You’re In
If you’re reading this because something just broke, you’re in Scenario A. Stop reading the rest of this article and call a supplier who can quote an exact ship date. “Estimated” isn’t a date.
If you’re in the middle of a design review or a retrofit, be honest: do you know the thrust load and duty cycle? If not, get an engineer involved before you buy. If the application is new, the motor-driver pairing matters as much as the actuator. That’s where I’ve seen the second-most failures—no, honestly, the most expensive failures. A wrong driver can cook both the motor and the controller.
If you’re ordering spares to have on the shelf, this is the moment to standardize. Pick your vendors, write down the part numbers, and make the maintenance team agree on what “stock” means. Then train yourself to ask one question when a bearing fails: was it the bearing, or was it the application? Because the answer tells you what to buy next.
There isn’t a single answer to “what causes thrust bearing failure?” There also isn’t a single electric actuator for every machine. But there is a process: determine the urgency, get the specs, and pay for certainty when downtime is the real cost.
Prices and lead times mentioned here are from our own purchase history as of early 2025. Verify current rates with your distributor; component availability changes.