Couple quick questions, We have RWF 316E Frick screws for our ammonia refrigeration. I've just started with the company this year and have inherited (4) 600hp units with chronic shaft seal problems and a system plagued with issues. So Im learning and attacking these one at a time. First question is does anyone have a general life expenctancy of a shaft seal? Does anyone have any background knowledge of these machines that may help lead to a solution, cause apparently our main service vendor has been working on this for some time and the people before me just throwing money at the problem, Id rather pay for a solution. Any thoughts? Any and all help is greatly appreciated!