Fusion Message Board

In this space, visitors are invited to post any comments, questions, or skeptical observations about Philo T. Farnsworth's contributions to the field of Nuclear Fusion research.

Subject: Re: Molecular Sieve Sorption Pump
Date: Feb 12, 4:52 pm
Poster: Ely Silk

On Feb 12, 4:52 pm, Ely Silk wrote:

> My mechanical pump appears to have the potiential of being a good roughing pump but will not get me down to where I need to be for anything approaching fusion and a diffusion pump is beyond my budget. Question: if using the mechanical pump for roughing, can the use of a Molecular Sieve Sorption Pump pull me into the 1 micron range or is this beyond its limits. The research tells me that it's possible for the MSS Pump to pull a 10 micron vacuum from 1 atm. and my thinking was if I could give it a head start down to about 25 microns maybe it would be capable to pull my chambers into the sweet spot.
>
>Stephen,

A sorption pump can get you down to the x-ray level if you need to. However, you will be spending lots of money on liquid nitrogen to activate the molecular sieve. Also, MSS pumping is slow. There are lots of vacuum equipment suppliers who sell diffusion pumps cheap! I think you will be happier with that approach - unless, of course, you own a liquid nitrogen liquefier!