The molecular worm gear pumps we use have been fine, and I would like to ask if the molecular turbine pumps would have problems if the UPS for the mass spectrometer did not work and the power went out? The impact of a power failure on a molecular turbine pump is of course huge, the blades at high speed suddenly lose power and stop, it is easy to break.

Try to avoid sudden power failure!  Power failure is not a big problem, will not cause a large airflow impact, so the blade will not explode.  No horror you say, that is also for the molecular turbine pump power cut off instantly quite a, not the voltage little by little become small.  Power outage molecular turbine pump will not stop immediately, but also slowly slow down the speed.  Shutdown, first stop the molecular turbine pump, and so it stops running, the corresponding fan and other auxiliary systems and then only stop.  When shutting down normally, you can see that no matter it is GC/MS or LC/MS, the vacuum pump is taking some time to stop, slowly reducing its speed, and of course to ensure that the normal power supply of the instrument. Otherwise how do you call it a normal shutdown? According to you, mass spectrometry has a voltage regulator or something like that? When shutting down, the voltage is slowly reduced. Like an electric fan when it is turned off, due to inertia, it stops slowly.  The normal shutdown of a mass spectrometer is to first de-energize the molecular turbine pump, slowly stopping it, and then stopping the corresponding auxiliary systems. Ensure that the molecular turbine pump is prioritized.  Very few molecular pump vanes explode, most are worn bearings. Have any of you ever changed the grease? Molecular pumps require specialized maintenance every 5,000 to 10,000 hours of operation (one year). Every 50,000 hours of work need to replace the bearings, and who has done?

In fact, in general, the turbomolecular pump is still very durable, minimize downtime, equipped with voltage regulators and high-quality UPS, and timely replacement of consumables and accessories to maximize its life Sudden power outages, the molecular turbine pump will not be able to dissipate heat, which may damage the molecular turbine pump.  No problem, the molecular pumps on the coating line are accelerated and decelerated every 10 minutes and use the dreaded motor reversal deceleration. It's all fine. Once we have a power outage, we immediately turn off the power supply, personal understanding of a sudden power outage should not be a big problem, afraid of a sudden call (at this time the turbine molecular pump is decelerating, blade operation is in an unstable state, the pump incoming call startup may make the blade of the deflection aggravated by the collision).  Sudden power failure on the ion source, four-stage rod, the mass detector is not too great, just a sudden power failure after the sudden call will have a greater impact on the electronic components, and may make the turbomolecular pump operation abnormal (turbomolecular pump shutdown and reopen between the time interval must be sufficient).

It shouldn't have much effect, I've lost power several times on that instrument. Nothing wrong with it after rebooting. However, it is important to prevent it from coming on suddenly, so we have installed a separate control box on the power supply, which can only be energized by manual startup after a power failure.  Vacuum System Power On and Off The vacuum system is an expensive component for a mass spectrometer. Maintaining the vacuum system of the mass spectrometer is very important for work safety and cost reduction.

Edit Turning on the vacuum system Edit Checking  

1. the temperature of the mechanical pump is less than 50°C. 2. the color of the mechanical pump oil is clear;   

2. the mechanical pump oil is clear in color and free from turbidity, opacity and stratification;  

3. make sure that the temperature of the molecular pump is less than 35 degrees Celsius. 4;   

4. If it is water-cooled pump, the circulating water of molecular pump should be turned on and there is no water leakage; Edit Starting the former mechanical pumps

1. turn on the mechanical pumps one by one, listen to the sound of each mechanical pump starting without any abnormality;  

2. open the vacuum gauge of the front stage; Edit Start the molecular pumps  

1. Make sure that the front-stage gauge air pressure is less than 1Torr (for non-compound molecular pumps it should be less than 20Pa);  

2. start the molecular pumps one by one and listen to the sound of each molecular pump starting without any abnormality;  

3. the molecular pump reaches full speed within 5 minutes, otherwise a shutdown is required;  

4. start the high vacuum gauge only after the molecular pumps reach full speed; Edit Shutdown of vacuum system Edit Shutdown of molecular pumps  

1. turn off the other instruments in the vacuum system at a temperature of less than 35°C. 2. turn off the high vacuum gauge;  

2. switch off the high vacuum gauge  

3. switch off the molecular pumps Edit Switch off mechanical pumps   

1. Make sure that the molecular pump speed is less than 30% or that it has been switched off for more than 10 minutes;  

2. turn off the pre-gauge  

3. turn off the mechanical pump   

4. open the venting valve, fill with argon or nitrogen, air, and close it after 5 minutes;  

5. turn off circulating water Edit shutdown inspection   

1. the color of mechanical pump oil is clear, without turbidity, opacity and stratification;   

2. the circulating water is clear, no turbidity; often said that the molecular turbine pump speed is very high whether there is a specific quantitative value of the speed of the check a bit, for reference: 90,000 rpm.

For reference: 90,000 rpm, 70L/s, Rotor diameter 60mm 27,000 rpm, 255L/s, Rotor diameter, 200mm 285m/s 637.36 miles/hr