Turbopump Maintenance Intervals, Bearings, Fault Signs
Service intervals for Pfeiffer, Leybold and Edwards turbopumps per their manuals, plus bearing change, lubricant and typical fault patterns.
How often a turbomolecular pump needs service depends mostly on its bearing design. Grease-lubricated bearings, lubricant reservoirs and lifetime-lubricated bearings each follow their own logic. This guide summarises what the public operating instructions from Pfeiffer Vacuum, Leybold and Edwards specify. Every figure applies to the named series and edition. The manual for your own pump always takes precedence.
Intervals according to the manuals
| Pump and source | Lubricant | Interval in the manual | Who does the work |
|---|---|---|---|
| Pfeiffer HiPace 300, PT 0200 BEN/I (03/2016) | Operating fluid reservoir | Reservoir and bearing at least every 4 years | Reservoir by the user, bearing by Pfeiffer Service |
| Pfeiffer TMH/TMU 261, PM 0470 BE/O (07/2009) | Operating fluid reservoir with TL 011 | Reservoir and bearing at least every 3 years | Reservoir by the user, bearing by Pfeiffer Service |
| Leybold TURBOVAC 35 to 361 C, GA05118_1502 (12/2006) | Bearing grease | Bearing exchange recommended after 15,000 operating hours at the latest | Leybold Service only |
| Leybold TURBOVAC 600 C and 1000 C, same manual | Bearing grease | Bearing exchange required after 10,000 operating hours at the latest | Leybold Service only |
| Edwards EXT556H, B777-50-880 Issue C | Lifetime lubrication | Typically more than 20,000 hours to bearing replacement, possibly less | Not by the user |
| Edwards nEXT, knowledge page on changing the cartridge and bearing module | Oil cartridge | Maintenance recommended every 35,000 hours | Possible for the user with a tool kit |
Pfeiffer calls for shorter intervals under extreme loads or impure processes and refers those cases to its service. Leybold also recommends a rotor exchange after 45,000 to 100,000 operating hours, depending on the thermal stress on the rotor. Edwards gives the fatigue life of EXT rotors as typically 40,000 to 50,000 cycles. It advises a major service with rotor replacement after 20,000 cycles from rest to full speed and back, or after 10 years, whichever comes first.
Lubricant and bearing change
At Pfeiffer, an operating fluid reservoir supplies the mechanical bearing. It is filled sufficiently at the factory, and topping up is not intended. On the HiPace 300 it sits behind the end cover at the bottom of the pump and carries nine Poroplast rods, which are replaced with tweezers during the change. Inside the pump, only a clean lint-free cloth may be used, without cleaning fluids. On the TMH/TMU 261 the procedure depends on the pump type. Pfeiffer points to the properties code after the model designation on the name plate and warns that a wrong procedure can destroy the pump.
The lubricant ages even at standstill. According to the HiPace 300 manual it keeps for at most 2 years without operation, or a total of at most 4 years across periods of operation and idling. For the TMH/TMU 261 the limit is 3 years of standstill. After that, Pfeiffer requires replacing the reservoir and bearings before restart.
At Leybold the bearing exchange is the central task, not a lubricant change. The pump may only be opened by persons authorised by Leybold. Slow venting extends bearing life, the manual adds. For the EXT556H, Edwards states that the bearings are not user-serviceable. It recommends a factory reconditioned replacement pump or a return to a service centre.
For the nEXT, Edwards describes the change of oil cartridge and bearing module as user work. The pump must be stationary and electrically isolated. Checking the bearing preload is essential, and Edwards states that a wrong preload may shorten service life. Afterwards the service indicator is reset. The manual for the specific nEXT size applies.
What you may do yourself
| Task | Pfeiffer HiPace 300 and TMH/TMU 261 | Leybold TURBOVAC 35 to 1000 C | Edwards EXT556H |
|---|---|---|---|
| Clean the outside | Yes, with a lint-free cloth and a little industrial alcohol | Light deposits on CF versions by baking out | External surfaces only, no solvents inside |
| Replace the lubricant reservoir | Yes | Not provided | Not provided |
| Replace the drive electronics | Yes | Not stated | Not stated |
| Replace the bearing | No, Pfeiffer Service | No, Leybold Service | No, exchange or service centre |
| Clean the inside, replace the rotor | No, manufacturer | No, manufacturer | No, manufacturer |
Pfeiffer requires a declaration on contamination with every return. Leybold sends equipment back to the sender if the declaration is missing. According to Pfeiffer, improperly performed maintenance voids liability and warranty.
Storage
Edwards advises avoiding long-term storage of the EXT556H. If unavoidable, run the pump at least eight hours every six months.
Typical fault patterns
| Symptom | Possible causes according to the manuals | Action |
|---|---|---|
| Pump does not start, no LED | Supply interrupted, wrong voltage, drive electronics defective | Check power supply, plugs and voltage, otherwise replace the electronics |
| Pump does not start, green LED flashing | Jumpers on the REMOTE connection missing or mating plug not fitted, for example the P 0920 668 E | Fit the mating plug or check the parameters via RS 485 |
| Final speed not reached | Backing pressure too high, leak, gas load too high, run-up time too short, overheating, bearing running hard | Check backing pump, seals and cooling, contact service if the bearing is suspect |
| Red LED on | Collective fault | Switch mains off and on, read details via RS 485 or control unit, otherwise service |
| Loud noise or vibration | Bearing damage, rotor damage, loose splinter shield, resonance with the system | Check the splinter shield, decouple vibration, otherwise the manufacturer |
| Ultimate pressure not reached | Gauge contaminated, leak, backing pump too weak, pump dirty | Leak search, bake out the pump, service if heavily contaminated |
| Overtemperature | Too little cooling air or water, high ambient temperature, high backing pressure | Improve cooling, reduce the load |
| Controller trips to Fail during run-up (Edwards EXC) | Inlet or backing pressure too high, too hot, rotor does not turn freely | Reduce the load, treat a stiff rotor as bearing damage and ask Edwards |
Edwards links irregular, worsening noise to a defective bearing and a constant high-pitched tone to rotor imbalance. If you suspect bearing damage, switch the pump off and ask Edwards.
Matching parts from the catalogue
Check fit against name plate and part number before ordering.
- PM P03 900 is a HiPace 300 with a DN 100 ISO-K flange. The intervals above apply to this series, so confirm the edition on the name plate.
- PM 006 459 AX is a vibration damper for HiPace 300/400 and reduces transmitted vibration.
- PM Z01 302 is the air cooling for HiPace 300 with TC 400 and helps with overtemperature.
- PM P02 821 H is a TMH 261 P, the type the TMH/TMU 261 manual covers.
- PM 063 266 -T is the lubricant reservoir (Y) listed in the spare parts table of the TMH/TMU 261 manual. The correct version follows the name plate.
- 117 64 and 153 00 are TURBOVAC 1000 C pumps, for which Leybold requires a bearing exchange after 10,000 operating hours at the latest.
- 854 72 is a TURBOTRONIK NT 150/360 frequency converter, as referenced in the TURBOVAC troubleshooting.
- B77751000 is the EXT556H with a DN160 ISO-K flange.
- B82200100 is an nEXT300D with an ISO100 inlet flange. Service follows the manual of that pump.
- B80000811 is an oil cartridge from the Edwards nEXT range.
FAQ
How often does a turbopump need servicing?
There is no universal figure. Pfeiffer states at least every 4 years for the HiPace 300 and at least every 3 years for the TMH/TMU 261. For grease-lubricated TURBOVAC pumps, Leybold gives 10,000 to 15,000 operating hours until the bearing exchange. Edwards recommends 35,000 hours for the nEXT and specifies no routine maintenance for the EXT556H.
May I change the bearing myself?
Not on Pfeiffer or Leybold pumps, where the manufacturer carries out the bearing exchange. The EXT556H bearings are not user-serviceable. Only for the nEXT does Edwards describe a user change with a tool kit. Pfeiffer notes that liability and warranty expire after improperly performed maintenance.
The pump does not reach full speed. What should I check first?
Check the backing pump, leaks, gas load and cooling, then the configured run-up time. If the rotor runs hard or the pump makes unusual noise, the manuals point to bearing damage. In that case stop the pump and contact the manufacturer.
Do you need one of the parts mentioned? We deliver the matching part with a quote the same day, and express shipping is possible.