Rotary Vane Pump Oil Change, Level and Oil Colour
Check oil level, change oil, read oil colour, use gas ballast and mist filters. Sourced intervals for Edwards RV, Leybold TRIVAC B and Pfeiffer DUO 5.
The oil seals and lubricates a rotary vane pump. Keeping an eye on level and condition shows process problems early. This guide summarises what the operating manuals of the Edwards RV series (RV3, RV5, RV8, RV12), the Leybold TRIVAC B (S and D 16 B, 25 B) and the Pfeiffer DUO 5 M say about oil changes, oil colour, gas ballast and service intervals. For your own pump, its matching manual always applies.
Which oil belongs in the pump
For hydrocarbon pumps Edwards names Ultragrade 19. PFPE prepared pumps run on Krytox 1506 or Fomblin 06/6, and a hydrocarbon oil must not be filled into them. Leybold specifies N 62 for the TRIVAC B and guarantees the technical data only with its recommended lubricants. Pfeiffer approves P3 (standard), F4 (corrosive gases) and D2 (special cases) for the DUO 5 M. Use only the grade filled at the factory, as shown on the rating plate.
Oil quantities
| Pump | Minimum | Maximum |
|---|---|---|
| Edwards RV3 and RV5 | 0.42 litres | 0.70 litres |
| Edwards RV8 | 0.45 litres | 0.75 litres |
| Edwards RV12 | 0.65 litres | 1.00 litres |
| Leybold TRIVAC D 16 B | 450 cm³ | 1000 cm³ |
| Leybold TRIVAC D 25 B | 600 cm³ | 1400 cm³ |
| Pfeiffer DUO 5 M | per rating plate | example in manual 0.75 litres P3 |
Checking the oil level
On the Edwards RV the level in the sight glass must sit between the MIN and MAX marks. You may check it while the pump runs, but topping up requires the pump to be switched off and isolated from the supply. If the level is above MAX, drain the excess through the drain plug. Leybold wants the level between the maximum and minimum marks and allows topping up only after switching off. Pfeiffer recommends checking on a running, warm pump, daily in continuous operation and at every start. Top up before the minimum is reached, up to Max, and tighten the DUO 5 M filler screw to 3.0 Nm.
Oil colour as a diagnostic
| Oil finding | Meaning | Action |
|---|---|---|
| clear and transparent | normal condition | keep checking regularly |
| darkening | aged or dirty oil (Leybold) | change the oil |
| reddish brown, colour number 5 to DIN 51578 | thermally aged P3 oil (Pfeiffer) | change now at the latest |
| cloudy, milky or discoloured | condensate or process vapours in the oil | degas (see gas ballast) or change |
| level below MIN, pump noisy or hot | too little oil (Leybold, Edwards) | top up, find the cause of the loss |
| level above MAX, oil in the inlet line | too much oil (Leybold) | drain the excess |
| solids in the oil, pump noisy | particle contamination (Edwards) | change oil, flush the pump |
| oil marks at the coupling housing | shaft seal damaged (Leybold, Edwards) | replace the shaft seal |
| ultimate pressure not reached | dirty oil or wrong grade | change oil and check the grade |
Pfeiffer also lists a missed ultimate pressure and, for mineral oil, a colour number above 4 as reasons to change.
Oil change step by step
Disconnect the pump from the mains and secure it against restart. Hot oil scalds, so wear protective equipment and use a large collecting vessel.
On the Edwards RV, run the pump for ten minutes to warm the oil, then switch it off. Open one filler plug, tilt the pump with a block under the motor and drain the oil through the drain plug. If the oil was dirty, flush with fresh oil until clean. Fill to MAX, wait a few minutes and top up if needed. Tighten plugs by hand only.
On the Leybold TRIVAC B, drain the oil, close the drain plug, run the pump for ten seconds at most and drain the rest. Check the plug gasket, then add fresh oil. The text of the manual says the pump should still be warm, while its maintenance plan says cold so that dissolved gases are not released. Follow the edition for your series.
On the Pfeiffer DUO 5 M the pump is vented and cooled down, with the oil still warm. After draining, close both screws and run the pump for five seconds at most. Then drain the rest, tilt the pump slightly, fill with new oil and check the level.
Service intervals
| Pump | Oil level | Oil change | Overhaul |
|---|---|---|---|
| Edwards RV3 to RV12 | monthly | every 3000 operating hours | every 15000 hours, new vanes every 30000 hours |
| Leybold TRIVAC S and D 16 B, 25 B | check while running | after 100 hours, then every 2000 to 3000 hours or yearly | service by Leybold, interval differs by edition |
| Pfeiffer DUO 5 M | daily | once a year at most | every four years at most |
Edwards recommends replacing the seals yearly with solvents, acids and abrasive gases, and a check at least every 14 days in unattended operation. Leybold shortens oil changes under harsh conditions. The Leybold editions disagree on the seal replacement interval, so no figure is given here.
Using gas ballast properly
Gas ballast admits air into the compression stage so that vapours do not condense in the oil. Edwards has positions 0, I and II. Position I suits low vapour loads and cleaning the oil, position II high loads. Both raise oil loss, so choose I first. To clean the oil, Edwards sets High Throughput mode and gas ballast I with the pump isolated from the system until the oil is clear. For ultimate vacuum the pump runs this way for at least one hour or overnight.
Leybold and Pfeiffer both give 30 minutes. After the process the pump keeps running with gas ballast open and the inlet closed until the oil is free of condensate. The DUO 5 M also warms up for 30 minutes with the inlet closed.
Oil mist filters
Edwards recommends an outlet mist filter with gas ballast open, inlet pressure above 10 mbar for long periods or frequent pump down from atmosphere. Trapped oil can be reused if it is not contaminated. Pfeiffer lists oil mist filters and oil return as accessories, Leybold exhaust filters with or without oil return. The outlet must never be blocked, because a clogged filter makes the pump run hot.
Seal kit and overhaul
Edwards points to its own service kits, which contain all parts needed. According to the manual, the Pfeiffer DUO 5 M overhaul kit covers seals, vanes, springs and wear parts of the safety and gas ballast valves. The smaller maintenance kit brings O-rings for the filler and drain screws, the cap seal and gas ballast valve parts.
Matching parts from the catalogue
Check fit against rating plate and part number before ordering, unless the name states the series.
- A65201131 is the clean and overhaul kit for the RV series.
- A65201130 is the blade kit for the RV3.
- H110-25-013 is Ultragrade 19 oil in four litres.
- A462-26-000 is the EMF10 outlet mist filter.
- A505-23-000 is the oil drain kit for EMF filters, named for RV3 to RV12.
- 197 21 is the seal kit for TRIVAC D 16 B and D 25 B.
- 101 91 is oil filter OF 4-25, listed as an accessory in the manual for the 16 B and 25 B.
- 177 02 is N 62 oil in five litres.
- 189 11 is the AF 16-25 exhaust filter for pumps of that size.
- PK E31 004 -T is the maintenance kit for DUO 5 M and DUO 5 MC.
- PK E32 008 -T is the overhaul kit for the DUO 5 M.
- PK 001 107 -T is P3 mineral oil in five litres.
FAQ
How often should I change the oil?
The makers give 3000 operating hours (Edwards RV), 2000 to 3000 hours or one year (Leybold TRIVAC B) and one year at most (Pfeiffer DUO 5 M). With vapours, dust or high load, change it sooner.
Is cloudy oil a reason to change it?
Cloudy oil usually holds condensate from the process. Edwards and Leybold first run the pump with gas ballast and a closed inlet until the oil clears. If it stays cloudy or the pump misses its ultimate pressure, change the oil.
Do I need an oil mist filter?
Edwards recommends one with gas ballast open, long operation above 10 mbar and frequent pump down from atmosphere.
Do you need one of the parts mentioned? We deliver the matching part with a quote the same day, and express shipping is possible.