Plain talk, with jokes

Robots don't take breaks, but they do take vacations: uptime, maintenance and the spare parts shelf

October 1, 2026 · 3 min read

The pitch says the robot runs around the clock. It does, between the times it does not, and those times are scheduled, mostly, by you. Here is what maintenance, wear parts and uptime actually look like for a cell in a small plant, and how to buy so that the vacations are short.

The short answer

Industrial arms are among the most reliable machines you will ever own. Tens of thousands of hours between failures is normal for the arm itself. The cell around the arm is another matter: suction cups wear, fingers chip, sensors drift, conveyors stretch, cameras get dirty, and the one proprietary cable nobody stocked fails on a Friday. Uptime is a property of the whole cell and of the shelf where the spare parts live, not of the robot.

What actually wears

On the robot: grease, batteries that hold the encoder positions, cables in the dress pack that flex every cycle, and eventually reducers after years of hard service. On the gripper: cups, pads, fingers, seals and the pneumatic valves behind them, which wear on a schedule you can predict from cycle counts. On the periphery: belts, bearings, proximity sensors, light curtains that get knocked, and cameras that need cleaning and the occasional recalibration. The arm is the part that takes the fewest vacations. The periphery takes the most.

Scheduled vacations

A cell wants a short daily look, a weekly clean, a monthly check of wear parts and a yearly service that may involve the integrator or the maker. Written down, that is perhaps an hour a week for a simple cell plus a day a year. Not written down, it is zero hours a week until it is a week. The honest operating cost line in every worked example on this site includes this time and these parts, because a payback that assumes a machine never stops is a payback that assumes a machine nobody owns.

Unscheduled vacations

The jam. The dropped part. The vision system that stops seeing the part because someone changed the lighting. The vacuum pump that loses a seal. Each is minutes if the recovery is known and the part is on the shelf, and days if neither is true. The spare parts kit the integrator offers at commissioning is the cheapest insurance in the project, and it is the line most often deleted from the quote to make the number look better.

Who comes when it stops

This depends on the machine, and the concierge on this site says which for each one rather than making a general promise. For some lines the maker carries warranty and parts and the integrator services the cell. For dealer lines, Steel Collar is the point of contact and routes the work to the people who do it. What this site will not do is claim factory trained technicians on staff, because there are none, and because a buyer who plans around a promise like that plans badly.

The uptime number to ask for

Not the robot's mean time between failures, which is a brochure number and a very good one. Ask the integrator for the cell's availability on a comparable installation after a year: the fraction of scheduled time it was actually able to run. Good cells live in the high nineties. Cells with a vision system and a messy infeed live lower, and the honest integrator will say so and tell you why.

The science fiction version

Every ship in every film has an engineer who spends the whole story keeping it running, and nobody in the audience finds that strange. Then the same audience buys a robot and expects it to run for five years on a handshake. Scotty had a spare parts locker. So should you.

If you want to know what the maintenance load looks like for the cell you have in mind, describe it to Joe, the concierge on this site. He will tell you which parts wear, who services each candidate, and what belongs on the shelf before the truck arrives.

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