Chromatography Forum

Hi all I need a bit of advice.

I am purchasing a used 6890+ 5973 GC/MS. It doesn't come with a foreline pump. I believe a Edwards E2M2 will work well with it. I was quoted for a an "Edwards EMF20 Oil Mist and Odor eliminator is which includes a new set of elements" Is that an acceptable part? I have an Agilent oil mist filter but it is for the Pfiefer duo 2.5 on my 5975.

Finally my main question is what are the requirements for the hose. I know it has to be wire reinfoced vacuum hose to withstand the pressure. Is there a specific OD I need and grade.

Will this do the job?
http://www.fishersci.com/ecomm/servlet/ ... hType=PROD

Check with Agilent to see what diameter and length is required to connect to the turbo or diffusion pump. You can then get the correct connector to fit the mechanical pump. The EMF20 is fine for the Edwards pump. Check with Scientific Instrument Services for the vacuum hose once you know what size you need. They have wire reinforced hose and rollerflex vacuum hose with lightweight PVC reinforcement cord at a good price.

All our 5973"s and 75 use a 1.5 pump. I would check with Agilent to confirm that an 02 pump isn't too big.

You're correct I am getting an E2M1.5

Just to add another complication there are E2M1.5's that are 110V and ones that are 220V. Almost all MS's are 110V so I need to be sure I get a 110V pump if I intend to plug it into the back of the MS so everyone should be adviced.

The Edwards E2M1.5 will need the EMF3 oil mist filter, it has an NW10 vacuum flange connection.
If the E2M1.5 has a hose nozzle exhaust connection and you want to add the oil mist filter, keep the hose fitting as they are costly to buy. A new EMF3 filter comes with a 3/8"BSP to NW10 adaptor, centering ring with o-ring and clamp. A new one costs $202 from Precision Plus, Edwards parts company. We can supply a "brand new - old stock" in original carton for $145 plus shipping, send an e-mail to HowardT@vacuumandlowpressure if interested. We sell the EMF Mist & Odor elements at the lowest prices, based in the US and ship all over the world.

I just transferred over the 3/8"BSP Agilent oil mist filter. It was aready equipped for it. The only issue I had was the inner diameter of the inlet KF16 flange was smaller than the Pfiefer duo so I needed a new centering seal with the lips on one side smaller for the pump and on the other side the same diameter for the foreline hose adapter.

I saw a foreline hose that had Tygon I forgot the number on it. Does that mean it is possible to buy the hose and transfer the internal spring over to a new hose?

The KF16 flange with a smaller bore would be the KF10 or NW10. The outside diameter of the flange is the same and the bore is either 10mm or 16mm approx. You can also buy a centering ring adaptor NW10 one side and NW16 the other. Tygon tubing with the criss-cross fabric reinforecement should be OK for small bores up to 3/4". If you go to 1" (25 mm) or above the steel wire reinforced hose would be best. Both are to prevent the hose from collapsing when under vacuum. The Agilent mist filter should be OK once you have the right connections, however they may have a higher price for the replacement elements when needed. My guess is that the mist filter is not an Agilent product. It may be private labeled for them. The best filters are ones that can be drained, in the event that the oil captured is contaminated. You shouldn't let contaminated fluid drain back into the pump. It may affect the vacuum level and/or cause corrosion - depending what is in it. Many Agilent mass specs use the Edwards EMF oil mist filters with an automatic drain back into the pump through the gas ballast, especially I believe on LCMS. The Edwards EMF20 has a larger capacity than needed for the small Duo 2.5. The EMF3 is the correct size. For the E2M2 you mentioned an EMF10 would be required due to the pump and filter flange size of NW25.

No such thing as too much rough pump. The E2M1.5 is not enough rough pump for the '73; you need a minimum of an E2M2. Even better would be an E2M5 (Edwards no longer uses these designations, but you can get good used rough pumps on eBay). SIS, as pointed out previously, is an excellent choice for this kind of supply, as well as good rough pump oil to keep your background low.

except how much power can the MSD power supply handle without blowing fuses or damaging the electronics?

I use good old Inland 45 in my rough pumps.

No such thing as too much rough pump. The E2M1.5 is not enough rough pump for the '73; you need a minimum of an E2M2. Even better would be an E2M5 (Edwards no longer uses these designations, but you can get good used rough pumps on eBay). SIS, as pointed out previously, is an excellent choice for this kind of supply, as well as good rough pump oil to keep your background low.

And the most funny thing is that Agilent is not aware of this and never was.
They supplied 5973 with Edwards E2M1.5. And on contrary to above "expertise" system works great.

Conclusion - E2M1.5 fulfils the needs of foreline pump for 5973. Besides it is known of it's long lasting, reliable service.

No such thing as too much rough pump. The E2M1.5 is not enough rough pump for the '73; you need a minimum of an E2M2. Even better would be an E2M5 (Edwards no longer uses these designations, but you can get good used rough pumps on eBay). SIS, as pointed out previously, is an excellent choice for this kind of supply, as well as good rough pump oil to keep your background low.

I would agree with this. I have had two E2M1.5 pumps die that were on my first two 5973s and another leaks terribly and we also had one of the Pfeiffer pumps on a 5975 die quickly. I replaced them all with old E2M2s that used to run on our 5995 and 5970 units from 20 years ago and they work great. Do not run them from the back of the 5973 though, rewire them to plug straight into and outlet and put a switch in the line just to be sure you do not overload the MSD. The thing I really like is that the M2s run much cooler, where the little pumps are usually so hot you can not touch them.

I believe it was SIS that did a study and proved that more pumping capacity will have no adverse effect on an MSD. If you pull away more effluent you will make it easier on your turbo pumps also.

As for oil, Inland 45, even my Agilent service engineers recommend it.