Automatic lubricators: how they work and when they pay off

An automatic lubricator is a lubricant reservoir with a mechanism that pushes a small dose to the lubrication point at regular intervals while the machine is running. The idea is simple: replace manual lubrication, done on a weekly or monthly route, with smaller and more frequent doses, which is the regime a bearing prefers.

The types

Single-point. One reservoir per point, mounted directly on the bearing housing or connected to it by a short hose. What varies is the mechanism that pushes the lubricant:

• Electrochemical or gas-driven: a chemical reaction produces gas that pushes a piston. No power supply is needed, but the flow rate varies with ambient temperature and the setting is not very precise.
• Electromechanical: a motor, powered by a battery or by the mains, drives the piston. The dose is more consistent, it can be programmed precisely, and this is the type that can be connected to a platform.

Centralized. A pump and a larger reservoir feed dozens of points through a network of lines and distributors. It is the standard on large machines, presses, long conveyors and mobile mining equipment. It costs more to install and requires the distribution network to be engineered.

What it solves

1. The right dose, frequently. Bearings tolerate both extremes poorly: too little lubricant leads to metal-to-metal contact; too much causes internal friction and heat. Small, frequent doses avoid both, which is hard to sustain with a grease gun and a spreadsheet.
2. Less contamination. Every time a point is opened in the field, dust gets in. A closed system cuts down on those openings.
3. Safety. Machine-safety rules generally require maintenance, adjustments and other interventions on machines to be carried out with the machine stopped, by trained and authorized personnel. Points that are high up, cramped or close to moving parts are exactly what an automatic lubricator takes off the manual route.
4. Forgotten points. Every lubrication plan has that bearing behind the guard that nobody remembers. The automatic lubricator does not forget.

Where it does not help

• Wrong sizing. Automating the wrong dose just gets it wrong more consistently. Dose and interval come from the bearing manufacturer's recommendation, taking speed, size, temperature and contamination into account.
• Incompatible lubricant. Mixing greases with different thickeners can soften or harden the lubricant. At installation, the point must be cleaned and the lubricant must be compatible with what is already there.
• Empty reservoir. An unmonitored lubricator stops when it runs dry, and nobody notices until the bearing tells them.

What changes when it sends data

That last item is the weak spot of a conventional lubricator: it works out of sight. An IoT-enabled lubricator reports the reservoir level and every discharge, with a timestamp, to the platform. This lets you:

• refill before it runs out, planning the refill route around actual consumption;
• know when a point has stopped discharging, due to a fault or an empty reservoir;
• keep a lubrication record for audits, instead of a signature on a spreadsheet;
• cross-check lubrication with vibration and temperature on the same bearing: a bearing that got its dose and keeps running hot has a different problem.

When it pays off

Start with the points where the factors add up: costly downtime, difficult or hazardous access, a history of bearing replacements and a dirty environment. A few well-chosen points make a good pilot; the rest of the plant stays on the manual route until the data shows where automation pays off most.

Where IoTData fits in

Our automatic lubricator is built in-house: it applies the programmed dose, and the reservoir level and every discharge show up on the platform, with alerts by email and WhatsApp before it runs out. See automatic lubrication and the automatic lubricator.

Sources: machine-safety regulations (maintenance and interventions with the machine stopped); general relubrication recommendations from bearing manufacturers; technical literature on industrial lubrication (electrochemical and electromechanical single-point lubricators and centralized systems).