Construction Machinery Lubrication
An excavator loads its boom foot pins and its slew ring every few seconds, in dust, in rain, and a long way from a workshop. We supply the automatic lubrication systems that keep those pins fed while the machine digs: grease pumps that run off the machine's own 12 V or 24 V supply, progressive distributors that feed every point in a fixed sequence, factory-fit to plant builders in India and as retrofit kits for owners and rental fleets.
The lubrication points
What a plant lubrication system feeds
The pins, bushes and the slew ring: the joints that carry load and move slowly under it. The hydraulics and the gear cases are separate oil charges and are not fed from this system.
Point 1
Boom foot & cylinder pins
The pins that carry the boom into the upper structure, and the pin at each end of every hydraulic cylinder. They move through a small arc under very high load, which is the condition a grease film is worst at surviving and a hand greasing round is worst at keeping up with.
Point 2
Slew ring raceway & gear teeth
The bearing the whole upper structure turns on, plus the open gear teeth that drive it. The raceway and the teeth are usually fed as separate points, and both are hard to reach and easy to skip on a manual round, so they are the ones that tend to fail first.
Point 3
Arm, bucket & linkage pins
The boom to arm pivot, the bucket pins and the linkage at the working end. Furthest from the pump, most exposed to dirt, and working in the abrasive spoil the machine is moving: fresh grease here is doing as much to push contamination out of the joint as it is to lubricate it.
Not this system
Hydraulics & gear cases
Hydraulic oil, the final drives and the swing gearbox are each their own charge on a drain and refill interval, and sealed track chain is lubricated for life at assembly. None of them is fed from the automatic greasing system, and none of them should be.
The architecture
Why progressive distribution suits plant
Two things decide the architecture here: the load, and the fact that nobody is watching. A pin under shock loading needs grease delivered at real pressure, and a machine working out on site needs a system that shows it has failed rather than quietly starving one bush for a season. A progressive distributor does both. Each piston has to complete its stroke before the next one moves, so the block feeds every outlet in a fixed sequence or it stops altogether, and a block fitted with an indicator pin can be checked by eye at a service to confirm the sequence is still cycling. The SD2 assembles from three to ten blocks and covers 1 to 20 points per combined distributor; it is also designed to work as the master distributor in a single-line system, which is how a machine with more points than one block set can carry is fed from a single pump. See how the three architectures meter a dose and choosing the right distributor.
Grease only, and at the heavy end of the range. This is the same architecture and much the same hardware as a vehicle chassis system, which is why a plant builder and a tipper builder often end up specifying the same pump: the difference is point count, pressure and how much abuse the mounting position takes.
| Point | Lubricant | Metering | Herg components |
|---|---|---|---|
| Boom foot & cylinder pins | Grease | Progressive, per-cycle dose | ZJ high pressure pump + SD2 distributor |
| Slew ring raceway & gear teeth | Grease | Progressive, separate outlets | ZJ high pressure pump + SD2 distributor |
| Arm, bucket & linkage pins | Grease | Progressive, per-cycle dose | ZD medium pressure pump + SD2 distributor |
| Smaller plant, hand-pumped | Grease | Progressive, one outlet | NKGH manual grease pump, 10 MPa |
| Line branching | N/A | N/A | TH joint fitting, 2 to 10 outlets |
| Monitoring | N/A | N/A | Pressure switch, gauge, filter, level indicator |
Built for the site
Running off the machine, out in the weather
The ZJ high pressure pump is the one built for this duty, and its own specification says so: it runs electrically at DC 12 V or 24 V off the host equipment's supply, which on engineering and mobile machinery means the machine's own battery. It is rated at 30 MPa through one or two outlets, each with its own piston mechanism, delivering 2 to 3 mL/min on a single mechanism and 4 to 6 mL/min on a double, with a fixed 0.12 cm³ per stroke or an adjustable 0.044 to 0.12 cm³ version in steps of 0.013 cm³. The housing is IP55, the reservoir is available in polycarbonate at 2, 3, 4 or 8 L or in metal at 2 or 4 L, and a paddle vents air out of the grease as the pump works, which matters on a machine that is refilled in the open.
Note where the two ratings meet: the ZJ is rated to 30 MPa and the SD2 distributor to 25 MPa, so a progressive circuit is set up to work inside the distributor's rating rather than the pump's headline figure. The same care applies to temperature. The ZJ is specified from −35 °C to +80 °C ambient but the SD2 works from −20 °C to +80 °C, so on a cold site it is the distributor, not the pump, that sets the lower limit. Grease has to suit both: the SD2 wants a penetration of 265 or softer at 25 °C, and the ZJ takes NLGI 000# to 2#. See choosing the right lubricant for the grade a given climate calls for.
Because nobody is standing next to the machine, the monitoring is part of the specification rather than an extra. The ZJ can report a pressure signal through a pressure switch fitted to the system and a level signal through a level switch, so a blockage or an empty reservoir can be raised in the cab instead of discovered at a service. The pump runs on its own controller for operating and rest time, or the machine's PLC takes that over, and every product comes with an installation and operating manual.
Who we supply
Factory-fit for plant builders, retrofit for owners
Plant & equipment builders
OEM production supply
Engineered to the machine's point count and pressure. If you build excavators, loaders, cranes or drill rigs, start with the pump range and the distributor range and we will match them to the machine.
Discuss an OEM programme →Owners & rental fleets
Retrofit & replacement
A machine on a daily grease gun round can be retrofitted without altering the structure: a pump bracketed to the upper structure, a progressive distributor sized to the existing points, and pipe run out to each pin.
Ask about a retrofit →Common questions
Construction machinery lubrication, answered
Which points does an excavator lubrication system feed?
The pins and bushes that carry load: boom foot pins, every hydraulic cylinder pin, the boom to arm pivot, the bucket and linkage pins, and the slew ring raceway and its gear teeth. Hydraulic oil and the gear cases are separate charges and are not fed from it.
Why progressive rather than another distributor?
Because it fails visibly. Each piston must complete its stroke before the next moves, so a blocked line stops the whole block instead of starving one pin quietly, and a block with an indicator pin can be checked by eye. On a machine nobody is watching, that property is worth more than the extra outlets a different architecture would give.
Does the pump run off the machine's own supply?
Yes. The ZJ pump is electrically operated at DC 12 V or 24 V and connects to the host equipment's power supply, which its specification names as engineering and mobile machinery. No mains supply or inverter is needed on the machine.
What pressure does a plant lubrication system run at?
The ZJ pump is rated at 30 MPa and the SD2 distributor at 25 MPa, with a minimum starting pressure of 1.4 MPa, so a progressive circuit is set up to work inside the distributor's rating. Where 18 MPa is enough, the ZD medium pressure pump covers the same job.
How cold can it work?
The distributor sets the limit, not the pump. The ZJ is specified from −35 °C to +80 °C ambient, while the SD2 works from −20 °C to +80 °C. Grease grade matters as much as the hardware rating: see choosing the right lubricant.
Is one distributor enough for a whole machine?
An SD2 assembly of three to ten blocks covers 1 to 20 points per combined distributor. A machine with more points than that is fed by using an SD2 as the master distributor in a single-line system, feeding secondary blocks out at the working end.
Can it be retrofitted to a machine in service?
Yes. The existing grease nipples are replaced with pipe connections fed from the distributor, so the structure itself is not modified. Point count, pipe routing and working pressure decide the pump and the number of distributor blocks. Send us an enquiry with the machine and its points.
Do you supply plant builders in India?
Yes. We supply construction and engineering machinery builders, owners and rental fleets across India, engineering the pump and distributor package to the machine's point count and pressure. Send us an enquiry with the machine and the points you need fed.
Building or running plant on a grease gun round?
Send us the machine, the pins and slew ring you want fed, and whether it runs on 12 V or 24 V.