Choosing the right lubricant
A centralised system is fussier about lubricant than a grease gun is. The grade has to be soft enough to pump the length of the line and stiff enough to stay where it is put. This page gives the grade or viscosity for each pump and distributor we supply, and the usual choice by application. For how the systems themselves work, see how centralised lubrication works.
NLGI grades
Reading a grease grade
Grease is graded by stiffness on the NLGI scale. The higher the number, the stiffer the grease. Centralised systems work at the soft end — a 3# cup grease that suits a hand-packed bearing will not travel down a 4 m feed line.
| Grade | Consistency | Typically used for |
|---|---|---|
| 000# | Semi-fluid — almost pours | Long pipe runs, many points, cold ambients, and systems that were designed around oil |
| 00# | Very soft | The usual choice for progressive systems with a long or branching pipe layout |
| 0# | Soft | General progressive and volumetric work at normal ambient temperature |
| 1# | Medium-soft | Shorter runs, warmer ambients, points that need the grease to stay put |
| 2# | Standard grease | Short runs and high-pressure pumps only — the stiffest a centralised system will normally handle |
Rule of thumb: the longer the line, the colder the site and the more points you feed, the softer the grade you want. If a system primes in summer but not in winter, drop a grade rather than raising the pump pressure.
By pump
What each pump takes
| Pump | Lubricant | Grade or viscosity |
|---|---|---|
| ZJ — high pressure | Grease or oil | NLGI 000# to 2#, or mineral oil from 40 mm²/s |
| ZD — medium pressure | Grease or oil | NLGI 000# to 2#, or mineral oil of 40 mm²/s |
| GM — motor-driven | Grease | NLGI 000# to 00# |
| NKGH — manual | Grease | NLGI 000# to 1# |
| TZ — motor-driven | Oil | 30 to 1000 cSt |
| HL — motor-driven | Oil | 30 to 1000 cSt |
The two grease pumps with the widest range — ZJ and ZD — will also run on mineral oil, which is worth knowing if a machine has both oil and grease points and you would rather not stock two pumps.
By distributor
What each distributor takes
| Distributor | Type | Grade or viscosity |
|---|---|---|
| SD2 | Progressive | Oil of ≥ 68 mm²/s at 40 °C, or grease of penetration ≥ 265 at 25 °C |
| 35 type | Volumetric | 20 to 500 cSt; grease 00# or 000# |
| 34 type | Volumetric | 20 to 500 cSt |
| RH3 | Volumetric | 20 to 500 cSt; grease 00# or 000# |
| TCJ & TCZ | Resist type | 20 to 50 cSt |
Resist-type distributors meter by flow resistance, so they are the most sensitive to viscosity on the list — a heavier oil than the range above changes the dose at every point, not just the far one.
By application
The usual choice by machine
| Application | System | Typical grade |
|---|---|---|
| Wind power — nacelle bearings | Progressive | NLGI 000# to 2# |
| Vehicle chassis & mobile plant | Progressive | NLGI 00# to 2# lithium |
| Forging & metal forming | Progressive | NLGI 000# to 2# lithium |
| Construction & engineering machinery | Progressive | NLGI 000# to 2# lithium |
| General machinery & gearboxes | Progressive | NLGI 000# to 2# lithium |
| Machine tools & CNC | Volumetric | Oil, 20 to 500 cSt |
| Plastics, printing & packaging | Resist type | Oil, 20 to 50 cSt |
| Hand-operated systems | Manual | NLGI 000# to 1# |
Before you fill
Four things worth checking
Match the grade to your coldest day
Grease stiffens as it cools. A grade that pumps happily through a July line can stall the same system in January. Pick for the coldest ambient the machine actually sees, not the average.
Don't mix thickeners
Lithium, calcium and polyurea greases can separate or harden when mixed, even at the same NLGI grade. When changing type, purge the reservoir and lines rather than topping up over the old grease.
Volumetric systems are forgiving of layout
A volumetric distributor delivers the same metered volume regardless of pump pressure or pipe length, and new oil needs no filtering before it goes in. That tolerance is the main reason they suit machines with many points spread a long way apart.
Keep it clean going in
Grit carried in with the lubricant is the most common cause of a blocked distributor. Wipe the filler and the container rim before filling, and keep the reservoir lid closed in a dusty shop.
Not sure which grade fits your machine?
Tell us the machine, the number of lubrication points, the length of the longest pipe run and the coldest ambient it works in, and we'll recommend a grade and the pump to match.