I have the same problem amnd I didn't know Edwards has a device for automatic
sealing. I think you use a single flame burner as I do, which is worst, but
you can use a double-flame burner with two entries: one of oxigen and the other
for regular methane gas. This is very efficient and even by hand, sealing
ampoules under vacuum by this method is much faster.
Ivano de Filippis
Rio de Janeiro-BRASIL
ivano at dinco.incqs.fiocruz.br