The drive is the part of a roller conveyor that decides how often maintenance is called. It also sets the noise level, the cleaning routine and the spare-parts inventory. The three common architectures are not interchangeable, even when they produce the same surface speed.
Key takeaways
- Gear motor with a line shaft is the most flexible and the easiest to service.
- Drum motors remove external drives and are preferred in washdown and tight spaces.
- Chain drives are robust and tolerate heat, but need guarding and lubrication.
- Match the drive to the environment first, then to the speed and torque.
Gear motor with a line shaft
A geared motor drives a shaft running along the side of the conveyor. Each roller is connected to the shaft by a small belt or a cardan. This is the traditional architecture and remains the most flexible. The motor can be mounted at either end, the shaft can be split for long conveyors, and a failed motor can be replaced without removing rollers.
The disadvantages are the exposed shaft, the belts and the space required at the side. In a cleanroom or a washdown area, the shaft and belts collect dirt and are difficult to clean. The belts also need periodic tensioning and replacement, which is a maintenance task that is easy to defer and expensive to forget.
Drum motor
The motor and gearbox are inside the roller. There is no external drive, no shaft and no belt. The conveyor is quieter, easier to clean and visually cleaner. Drum motors are the default choice for food processing, pharmaceutical packaging and any line where washdown is routine.
The trade-offs are cost and serviceability. A drum motor costs more than a comparable gear motor, and a failure means removing the drum. Keep a spare drum in stock for critical lines. Drum motors also have a fixed speed unless a VFD is used, and the speed range is narrower than a gear motor with a variable ratio.
| Criterion | Gear motor + shaft | Drum motor | Chain drive |
|---|---|---|---|
| Space at the side | High | None | Medium |
| Washdown | Poor | Good | Fair |
| Noise | Medium | Low | High without guard |
| Maintenance | Belts and bearings | Sealed, low | Chain lubrication |
| Initial cost | Low | High | Medium |
| Speed change | Easy with VFD | VFD or change drum | Change sprocket |
Chain drive
A chain runs along the side of the conveyor and drives sprockets on each roller. It is robust, tolerates heat and dust better than belts, and can transmit high torque over long distances. It is common on heavy-duty roller conveyors and on lines that operate in high-temperature ovens.
The chain must be guarded, lubricated and tensioned. An unguarded chain is a safety hazard, and a dry chain is a noise source. In food areas, an open chain is usually unacceptable because it cannot be cleaned to the required standard. In those cases, a drum motor or a sealed chain in an enclosure is preferred.
Selection rules that hold up in practice
For a clean assembly area with light cartons and a need to change speed, use a gear motor with a VFD. For a washdown or cleanroom line, use a drum motor even if it costs more; the cleaning time saved over a year usually pays for the difference. For a heavy pallet line or a high-temperature section, use a chain drive with a proper guard and an automatic lubricator.
If the conveyor is longer than about 15 metres, consider splitting it into zones with separate drives. A single drive on a long line has to move the entire load, and the chain or shaft loads become difficult to manage. Zoned drives also let you stop one section without stopping the whole line.
Noise, efficiency and total cost
A drum motor is typically quieter than a gear motor with a shaft, because there are no belts or exposed gears. A chain drive is the loudest unless it is enclosed and lubricated. Efficiency is highest for the drum motor at full load, but the difference is small compared with the energy used by the conveyor as a whole.
Total cost should include spares. A gear motor needs belts, bearings and eventually a motor. A drum motor needs a spare drum. A chain drive needs chain, sprockets and lubricant. The cheapest drive to buy is rarely the cheapest to own over five years.
Frequently asked questions
Can a drum motor be repaired on site?
Usually not. Drum motors are sealed units and are typically replaced rather than repaired. Keep a spare for critical conveyors and return the failed unit to the manufacturer for overhaul.
Is a VFD necessary on a roller conveyor?
It is necessary when the line speed must match a takt time, when soft starts are needed, or when the conveyor handles fragile products. For a simple transport conveyor running at a fixed speed, a VFD adds cost without much benefit.
How often should drive belts be replaced?
Inspect monthly and replace when glazing, cracking or slack is visible. On a three-shift line, plan a full belt replacement every 12–18 months even if the belts still look serviceable.
Tell us the product weight, conveyor width and environment, and we will recommend a drive architecture with the spare-parts list. See the powered roller conveyor page for the mechanical options that go with each drive.
