How a Spring-Driven Lubricator Works
A spring-loaded single point lubricator is a purely mechanical device. A coil spring pushes a piston against a grease or oil reservoir, driving lubricant through a flow-control orifice to one bearing point at a steady rate. No battery, no gas cartridge, no wiring, no electronics.
It is the mechanical half of the single point lubricator family — set the discharge with spring and vent, no power, no controller.
The spring holds nearly constant force, so outlet pressure stays consistent as the reservoir drains. It fits unattended points where power is unavailable or battery changes are impractical: one option in the broader automatic lubrication field, trading programmability for simplicity.
A flow-control adjuster changes the effective orifice size: slower stretches the refill interval, faster feeds high-consumption points. The outlet thread is 1/4″-28 UNF, with metric and BSP adapters included.
Technical Specifications
| Parameter | Specification |
|---|---|
| Capacity options | 60cc (2 oz) / 237cc (8 oz) / 532cc (18 oz) |
| Spring output pressure | Up to 4 bar (65 PSI), steady across the stroke |
| Operating temperature | -20°C to +100°C (-4°F to 212°F) |
| Compatible lubricants | NLGI 000 to NLGI 2 grease; lubricating oils |
| Reservoir | Transparent polycarbonate, level visible at a glance |
| Outlet thread | 1/4″-28 UNF; metric and BSP adapters included |
| Discharge control | Adjustable flow-control orifice |
| Drive | Mechanical spring; no power, gas, or electronics |
| Service | Refillable and reusable; refill when the piston is about 10-15mm from the bottom |
Capacity and Refill Intervals
Three reservoir sizes cover most duties: 60cc (2 oz) for tight spaces and small doses, 237cc (8 oz) for general industrial bearings, and 532cc (18 oz) for remote or elevated points. At a standard discharge setting, typical refill intervals run about 1-2, 2-4, and 4-6 months. These are typical figures, not guarantees; the real interval depends on discharge rate and bearing consumption.
| Capacity | Typical refill interval at standard setting | Best suited to |
|---|---|---|
| 60cc (2 oz) | About 1-2 months | Tight spaces, small doses, frequently checked points |
| 237cc (8 oz) | About 2-4 months | Most general industrial bearings |
| 532cc (18 oz) | About 4-6 months | Remote or elevated points, high-consumption bearings |
To size a unit, multiply the daily requirement by the days between visits: a point using about 1cc per day across a 6-month cycle needs roughly 180cc, so the 237cc unit covers it. Note the housing thread and daily requirement, or request a quote to have sizing done for you.
The transparent reservoir shows the level at a glance. Refill when the piston sits about 10-15mm from the bottom; do not run it dry, since air in the feed line can contaminate the point and stop the feed. Servicing means refilling, wiping clean, and reinstalling.
Spring vs Battery and Gas Designs
| Feature | Spring-loaded (this unit) | Battery-operated | Gas-pressure |
|---|---|---|---|
| Drive | Coil spring on a piston | Internal battery and electrochemical cell | Cartridge gas pressure |
| Output pressure | Steady, up to 4 bar (65 PSI) | Set by electronics, varies by model | Declines as the cartridge empties |
| Cold-weather behavior | Spring force unaffected by temperature; grease still thickens | Battery capacity drops in the cold | Output falls in the cold |
| Consumables | None beyond the lubricant; refillable and reusable | Battery replacement, typically every 1-24 months depending on the model | Cartridge swap; most units are single-use |
| Typical failure modes | Spring fatigue over long service; orifice blockage | Battery depletion; electronics fault | Gas leak; valve sticking |
| Best suited to | Simple continuous feed, no power, cold or remote sites | Timed cycles, empty signalling, monitored points | No-power sites needing more pressure than a spring provides |
The 4 bar (65 PSI) spring output is an honest boundary: it suits most standard housings on short, direct feeds, but can fall short against heavily spring-loaded seals, long or narrow-bore lines, or NLGI 2 grease in the cold. Those cases need a gas-drive unit or a pump-fed system; for many-point machinery, see grease pump systems and the heavy equipment lubrication system overview.
Installation and Maintenance
- Fill with the lubricant specified for the bearing; do not mix incompatible grease thickeners.
- Set the discharge adjuster to the calculated rate before mounting.
- Thread the outlet into the grease port with the right adapter and PTFE sealant tape; tighten firmly.
- Check the level at the first inspection to confirm the expected flow.
- Refill on schedule, wiping the outlet and port clean before reinstalling.
Frequently Asked Questions
How is a spring-loaded lubricator different from battery or gas types?
All three feed one point without a central pump. A spring-driven unit pushes lubricant continuously and needs only refills; battery units add timed cycles and empty signals but need battery swaps, typically every 1-24 months depending on the model; gas units run on a cartridge and are mostly single-use. Choose spring-driven for simplicity and no-power sites.
Which capacity should I choose?
Match the reservoir to the daily requirement and visit frequency: the 60cc unit fits tight spaces, the 237cc covers most industrial bearings, and the 532cc suits remote points.
How do I set the discharge rate?
Convert the manufacturer’s relubrication quantity to a daily figure and set the orifice so the reservoir spans the interval between visits; begin slightly slow and confirm flow at the first inspection.
Can I use NLGI 2 grease?
Yes. The compatible range runs from NLGI 000 semi-fluid grease to lubricating oil, with NLGI 2 at the top. In cold sites, prefer NLGI 0 or NLGI 1: stiff grease moves slowly through the orifice.
Is 4 bar enough pressure for my bearing point?
Usually, for standard housings on short, direct feeds. Heavily spring-loaded seals, long narrow-bore lines, or cold NLGI 2 grease can defeat it; those cases need a gas-drive unit or a pump-fed system.
Can I mount it in a hazardous or classified area?
With no electrical parts and no gas cartridge, the ignition concerns of powered lubricators do not apply. The unit carries no hazardous-area certification, so classified-zone use must be approved by the responsible safety officer.
How do I know when to refill?
The transparent reservoir shows the level without removal. Refill when the piston sits about 10-15mm from the bottom; do not wait until completely empty.
What happens if it runs completely dry?
The spring keeps pushing until nothing remains, then the unit feeds air. Air breaks the continuous film the bearing needs and can carry moisture into the housing. Refill, then verify flow at the next inspection.
Can I program it or monitor it remotely?
No. There is no timer, sensor, or communication function; the unit feeds continuously from installation until empty. For timed cycles or status alarms, choose a monitored automatic lubrication system instead.
Who makes this unit and how do I order?
For capacity selection and pricing, use the quote request page or email inquiry@isohitech.com. IsoHiTech Lubrication Systems was founded in 2023, engineering since 2006, and can size the unit against your bearing specifications.
