Several frequent errors might occur in the laboratory while employing vacuum pumps. These mistakes are common in university laboratories since graduate students cycle out every few years. As older, more experienced grad students leave and new ones come in, a lot of vacuum knowledge can be lost. When people haven't had enough time to learn safety procedures and acquire enough training on the equipment, accidents may and do happen. However, mishaps involving vacuum pumps may occur in any laboratory when not following correct protocols.
Accidents with Oil Vacuum Pumps
When improperly handled, oil-sealed pumps may suffer oil backstreaming (also known as suck back) from the pump into manifold, valves, or even the process chamber.
This kind of accident happens when there is oil in the pump, the power goes out, or the system is shut down wrong. The vacuum can recirculate oil from the pump into the chamber and the vacuum lines if they are still under vacuum after the power has been off. It causes contamination in the chamber and may even taint the pump and other parts housed within it. It's hard to get all that oil out of the system, hurting productivity and making the vacuum system contaminated with oil or oil vapor.
Most oil pumps have anti-suck-back valves that keep this from happening, but not all do. However, the anti-suck back valve in the pump absorb oil into the valve O-ring/gasket, causing swelling of the elastomer seal. So even a pump with an anti-suck back valve can have oil or oil vapor leakage, unless the pump is properly maintained, and the suck back valve is replaced as necessary. One alternative is to install inline safety valves. However, these devices are not without risk. Those safeguards will not guarantee success; this failure mode is still possible. A dry pump eliminates the need for oil and is thus the most reliable option. Even if a valve fails on a dry pump, no oil will leak into the system and pollute it. But dry pumps literally “come at a cost.” As the dry type of roughing pumps are significantly more expensive than oil lubricated pumps.
Accidents with Turbopumps
It is possible to damage a turbopump by operating it at full speed while the pressure within the chamber is still atmospheric. Inadvertently opening the valve between them may unleash a torrent of air pressure onto the pump, causing it to fail. Turbo rotors and blades, which operate inside the pump, and bearings, are vulnerable not just to damage, but based on the pressure differential the internal moving parts of the turbo pump can literally be destroyed.
Such an incident is common in laboratories that use vacuum technology. It is known as shock venting to the atmosphere. Training is necessary to prevent this sort of accident. The pump must always be used with extreme caution. An automated system may check the chamber's pressure using a gauge to see whether it has dropped to a certain level. The chamber might also be linked to a turbopump, which would then be used to pump the chamber down. Because of this, when the turbopump is activated, it will already be at optimal pressure.
Procedures to Follow to Prevent Accidents in the Laboratory
The following recommended practices may help prevent errors in the laboratory in addition to instruction on how to operate vacuum pumps correctly:
● Use gauges to check that the pressure on all high vacuum pumps are at a safe level before turning them on.
● If you are working with a high or ultra-high vacuum system, you should always protect the chamber from fingerprints by wearing gloves.
● Keep vacuum pumps and their surroundings immaculately clean.
Having Trouble with Your Vacuum Pump?
Vacuum Pump Repair USA has the tools and expertise to diagnose and fix any problems with your pump. Vacuum pumps are complex machines that require a high level of knowledge to assess and repair any issues. If you've noticed a lot of noise or any unusual feature, you should have it checked out by a professional from our company. Regardless of the cause, vacuum pump repair (on a as needed basis) and preventative maintenance for long-term usage, will likely save you money in the long run. Contact us today! Please visit our website at: www.avac.com or give us a call at 714-938-1300. Thank you!