Mass Spectrometry is a analytical technique that makes and sorts molecules based on mass. In order to make and move ions, a sufficient vacuum is required. In order to make a good vacuum, GCMS Mass Spectrometers need o-rings.
Most o-rings, once put in place are never disturbed and are good for years but eventually they need to be attended to. Most are easy to get to and are inexpensive and can just be replaced. Such as for the rough pump, diff pump, ion gauge, calibration valve, etc...
The HP 5971, HP 5972, HP 5973 and Agilent 5973 all contain similar o-rings.
The most troubling are the ones that seal the analyzer plate to the manifold. Some are proprietary seals, not really o-rings. For a thorough PM one should replace all o-rings but that seldom happens. And often when you have a leak problem, you don't have the o-rings you need. The alternative to replacement is to clean and condition the ones that are there and put them back.
Here's how we do it at CSS Analytical.
Some technicians have said to clean the o-rings with a solvent but I would caution you against using solvents for this task. Using a solvent will "suck the life" out of an o-ring and possibly even leave enough solvent in the o-ring to "out gas" for several days after you attempt to pump down and run.
Instead, use Apezion L or N as both a "cleaning" and "conditioning" media.
Glove up, put a sufficient amount on your finger, massage it a bit between your fingers to warm it up and thin it out. Rub it in thoroughly, going around the entire o-ring several times. Now, clean your gloves with a clean, lint free cloth. Attempt to remove as much as you can with a your gloved fingers. Repeat the procedure again. Clean your gloves repeatedly with a clean lint free cloth, and each time try to remove as much grease as you can. This method will leave JUST A LITTLE Apezion in the "micro" structure of the o-ring .... the less the better, especially on any o-rings near the ion source.
Now you have cleaned and conditioned your o-ring. Put it back in place and good luck.
To replace all your 5971, 5972 and 5973 o-rings contact us - we usually have all of them in stock.
