TURBOVAC Molecular Pump Maintenance Guide

If particles may be generated in the chamber, a fine mesh filter should be installed between the high vacuum flange and the pump.

For vibration sensitive equipment, a dedicated vibration damper can be installed at the high vacuum flange of the pump. If the TURBOVAC 1000 C is connected through a shock absorber, it must be additionally fixed at the base flange.

2.4 Installation posture

Due to the use of grease lubricated bearings, TURBOVAC can be installed and operated in any posture (horizontal, vertical, inverted, etc.) without the need for additional support.

Cooling method selection: When do you need water cooling?

The operating temperature of TURBOVAC directly affects the bearing life and pumping performance. The manual provides a clear cooling demand decision table based on ambient temperature, pre stage pressure, and high vacuum pressure.

3.1 Air cooling vs. water cooling

No additional cooling required: When the ambient temperature is less than 30 ° C, there is no baking, the high vacuum pressure is less than 10 ⁻ mbar, and the pre stage pressure is less than 5 × 10 ⁻¹ mbar, the TURBOVAC 35 LS can be naturally cooled.

Air cooling: When the ambient temperature is 30-40 ° C or there is baking or high pressure, an air cooling unit (fan) needs to be installed. During installation, keep the fan at least 20 cm away from surrounding objects to avoid inhaling hot air from nearby equipment.

Water cooling: Water cooling must be used when the ambient temperature is>40 ° C (or>45 ° C depending on the model), or when operating continuously under high vacuum pressure>10 ⁻⁴ mbar, fast cycle operation, baking temperature>35 ° C.

3.2 Cooling water specifications

The manual specifies strict water quality requirements:

Inlet pressure: 3-7 bar (absolute pressure)

Appearance: Colorless and transparent, oil-free and fat free

Sediment:<250 mg/L

Particle size:<150 μ m

PH value: 7-8.5

Total hardness: ≤ 20 ° German hardness (approximately 3.57 mmol/L)

Water quality that does not meet the requirements can cause scaling or corrosion in the cooling channel, affecting heat dissipation.

3.3 Cooling water flow rate

Figure 7 in the manual shows the cooling water consumption curves for different models. For example, TURBOVAC 151/361 has a flow rate of approximately 60-100 L/h at an inlet water temperature of 20 ° C. It is necessary to ensure sufficient flow, otherwise an overheating alarm will be triggered.

Purge Gas and Treatment of Corrosive Media

Meaning of Version 4.1 C

Pumps with "C" in the model (such as TURBOVAC 151 C, 361 C, 600 C, 1000 C) are equipped with a purge gas interface to protect the bearing and motor areas from corrosive gases.

Manual warning: "TURBOVAC is not suitable for corrosive or dusty media unless appropriate attachments are used. When dealing with corrosive media, the C-version pump must use purge gas; When dealing with dusty media, a fine mesh filter must be installed. ”

4.2 Applicable gases

Recommended gases: Inert gases such as nitrogen (N ₂) or argon (Ar), temperature 5-80 ° C, relative humidity ≤ 10 ppm.

In special circumstances: After consultation, dry, filtered, oil-free air (filtration accuracy<1 μ m) can be used. The filter needs to be replaced regularly (at least once a year).

4.3 Blowing gas flow rate and function

The blowing gas forms positive pressure in the bearing and motor areas to prevent corrosive process gases from flowing back into sensitive components. When the pump is stopped, it is also necessary to ventilate by blowing the gas valve to ensure that the pressure in the bearing area is higher than that in the other vacuum areas, in order to prevent particles or corrosive gases from being pressed into the bearing.

Precautions for startup, baking, and operation

5.1 Starting pressure

TURBOVAC must be started under a certain pre stage pressure, otherwise it will cause motor overload and heating. Manual Figure 8 shows the starting pressure curve: for most models, the starting pressure should be less than 10 ⁻¹ mbar (such as TURBOVAC 50/151/361 starting pressure of 1 × 10 ⁻¹ mbar). If the ratio of the pumping speed of the front stage pump to the chamber volume Sf/V is greater than 100 h ⁻¹, both the front stage pump and the turbo pump can be started simultaneously.

5.2 Baking

To achieve a maximum pressure below 10 ⁻⁸ mbar, the vacuum chamber and TURBOVAC need to be baked. Pumps using CF flanges can be equipped with flange heaters, with a maximum baking temperature of 100 ° C. Precautions:

Protect the rotor from strong thermal radiation.

The heating temperature of the front stage side (such as adsorption trap) shall not exceed 80 ° C.

During the baking period, the front-end pump must continue to operate to extract the released steam.

5.3 Hazards during operation

High temperature burns: If the pump body temperature is greater than 70 ° C, warning signs are required.

Vibration: Avoid excitation of rotor resonance by acceleration force during pump operation. If the natural frequency of the system causes resonance, it can be solved by changing the mass or installing shock absorbers.

Common troubleshooting: from "not starting" to "maximum pressure not meeting standards"