Pressure ratio: 50:1 | Air input: 40-150 PSI (2.8-10.3 bar) | Maximum output: 7,500-10,000 PSI (517-690 bar) | Container: 120 lb (55 kg / 16 US gal) keg
The 120 lb pneumatic grease pump from IsoHiTech Lubrication Systems is an air-operated, keg-mounted unit for daily greasing crews. A double-acting air motor drives a positive-displacement piston at 50:1 on a standard 120 lb (16-gallon) keg. IsoHiTech Lubrication Systems was founded in 2023, engineering since 2006. Request a quote with your keg diameter and grease grade.
Specifications
Figures below are declared values; anything not listed (air consumption, noise, net weight) is confirm at order.
| Parameter | Declared value |
|---|---|
| Pressure ratio | 50:1 |
| Air input range | 40-150 PSI (2.8-10.3 bar) |
| Maximum output pressure | 7,500-10,000 PSI (517-690 bar) |
| Container size | 120 lb (55 kg / 16 US gal) keg |
| Container reference dimensions | 11.25-11.75 in ID, 14.5-15 in height |
| Follower plate | OD 10.8 in (274 mm), dual-lip nitrile seal; scraper option for high-contamination areas |
| Grease consistency | NLGI #000-#3; NLGI #2 at 25 °C runs smoothest |
| Assembled height (typical set) | 36-40 in (914-1,016 mm) |
| Base footprint | 18 x 18 in |
| Gross weight (typical set) | 45-65 lb (20-29 kg) |
| Air consumption | Confirm at order |
| Noise level | Confirm at order |
| Pump net weight | Confirm at order |
How the 50:1 Ratio Works
Output pressure is simple multiplication: Output PSI = Air PSI x 50. At 90 PSI shop air the piston delivers 4,500 PSI grease; at the 150 PSI ceiling of the input range, 7,500 PSI. The 10,000 PSI top of the declared range depends on configuration – ask what your setup can reach. The double-acting air motor exhausts about 1.5x its intake air volume, so plan the exhaust side too. For ratio selection, see our grease pump pressure ratio selection guide.
Container Fit: 120 lb and 16 Gallons Are One Keg
“120 lb” and “16 gallon” describe the same keg two ways: grease weight when full, and volume. These kegs measure 11.25-11.75 in ID and 14.5-15 in tall, and the 10.8 in OD follower plate with dual-lip nitrile seal rides the keg wall down as grease is used. A scraper option suits dusty environments.
Installation Reference
General workshop practices, not product ratings:
- Air line: 3/8 in ID under 25 ft, 1/2 in ID for 25-50 ft, 3/4 in ID beyond 50 ft.
- Fit a filter-regulator with 5-micron filtration; regulate working air to 90-110 PSI.
- Tighten drum cover bolts to 18-22 Nm.
- Ground the pump body to the keg against static.
Hose and Coupler Reference
- Grease hose: minimum burst 12,000 PSI (4:1 safety factor over 3,000 PSI working).
- Swivel joint: 360-degree rotation at 5,000 PSI.
- Coupler: 4-jaw standard, or 6-jaw large-flow for high-volume work.
- Zerk adapters: 1/8 in NPT standard, 1/8 in BSPT optional.
- Pressure drop: roughly 500 PSI per 50 ft of 3/8 in hose at 1 lb/min.
Before You Order: Two Honest Limitations
- Not for oil. The positive-displacement piston is built for semi-fluid grease; low-viscosity oil leaks past it internally and never builds pressure.
- Not a 55-gallon pump. Extended tubes of 400 lb and 55-gallon pumps, 38 in and longer, sit wrong in a 120 lb keg; match the tube to your tier.
Container Size Navigation
This pump sits mid-range in IsoHiTech’s keg-mounted line. For lighter pail service, see the 5-gallon pneumatic grease pump; for the metric format, the 25 kg pneumatic grease pump. If a keg lasts only days, step up to a 55-gallon drum setup – a different tube and follower plate, not an accessory for this unit.
Maintenance Schedule
| Interval | Task |
|---|---|
| Daily | Wipe the piston rod; check connections for leaks |
| Weekly | Drain the filter-regulator trap |
| Monthly | Oil the air motor; inspect hose and swivels |
| Annually | Replace piston seals; check the follower plate seal |
Frequently Asked Questions
What is a 120 lb pneumatic grease pump?
It is an air-operated grease pump that mounts directly on a 120 lb (16-gallon) keg. A double-acting air motor drives a positive-displacement piston at 50:1, pushing grease through a hose to each fitting: the step up from hand guns.
Is a 120 lb keg the same as a 16-gallon keg?
Yes. “120 lb” names the keg by grease weight, “16 gallon” by volume; both are one container. Reference kegs are 11.25-11.75 in ID and 14.5-15 in tall, hence the 10.8 in follower plate.
How does air pressure relate to output pressure?
Multiply by 50. At 90 PSI air you get about 4,500 PSI grease; at the 150 PSI top of the input range, 7,500 PSI. Stay inside the declared 40-150 PSI input range.
Can this pump dispense oil?
No. The piston and seals are built for semi-fluid grease; low-viscosity oil bypasses the piston internally and pressure never builds. Use a dedicated oil transfer pump.
Which grease consistency grades work?
NLGI #000 through #3. NLGI #2 at about 25 °C runs smoothest; for NLGI #3 or below 10 °C ambient, preheat the grease to about 30 °C before pumping.
How do I size the air compressor?
Size for duty cycle, not the first minute: a small compressor can start the pump yet stall under sustained cycling. Air consumption is confirm at order, so request a quote with your duty cycle details.
How should I rate the hose and couplers?
The weakest component sets the ceiling: hose bursting at 12,000 PSI or more, swivel within its 5,000 PSI rating, adapters rated for your working pressure.
Why won’t a 55-gallon or 400 lb pump fit my keg?
Those pumps use longer tubes, 38 in and beyond, sized for full-height drums; a 120 lb keg is about 15 in tall, so the geometry is wrong. Each tier has its own pump; parts do not mix.
What routine maintenance does the pump need?
See the maintenance schedule above for the full cadence.
Related Resources
Read how a pneumatic grease pump works or the complete guide to grease pumps. Questions? Email inquiry@isohitech.com.
