quote:
WRONG!! They could both have the same paper, and most likley do in these spring rates. The difference would be the rating of the spring in the bypass valve. 8-11 pounds is not the same as 16 pounds. No matter what.
Well, I think you got the assertion wrong.
Do you use robust media that can withstand 30 psid without collapse ,...but would rather bypass unfiltered oil for your customers?? Or would you put a 22 psi bypass on your current 8-11 and let it rupture and then bypass all kinds of unfiltered oil?
So, can we reasonably assume that bypass setting correlate to the ability of the media to withstand stress? That they are a safety mechanism that is "married"/integrated into the package? Or is it just some arbitrary whim of some engineer?
Now I don't think that having a higher bypass setting will mean that you have a "better" filter in terms of holding capacity ..but I think that it's not too much of a stretch to believe that the higher the bypass setting, the more substantial the media is and the more stress, in terms of differential pressure, it can withstand.
Well, one could say "but it conforms to manufacturer's spec's. Then I would ask "Well which company is violating them? Is it Wix with their routine and consistant 8-11 ..or Purolator with their higher bypass setting (VW filters exempt for all) ..or is Donaldson and Baldwin with their "all over the board" approach (prehaps more custom to the application) ..but why would a filter manufacturer decide to bypass MORE oil with a lower bypass setting if they, in fact, used a media that could sustain more PSID ..assuming as you assert that they're using the same paper??
Anything wrong with what I said there
Additional edit: Now I can see the "paper" being in a "range" of acceptable bypass settings. That is, that your 8-11 paper can take 12-19 ..like (I think) Purolator tends to run ...and you surely could compensate with more media so that loading will impact the media less so that your 8-11 will bypass no more oil than a Purolator at the higher setting. I can also see that higher bypass ratings can potentially cause some issues in some applications depending on how the oil system is configured and how close the system is to its relief settings.
But I would like to understand how your generic 8-11 is justified across the board. I would like to understand how Purolator functions with the same, or superior, distinction with its higher setting. I would also like to understand that if both are acceptable ..and are allegedly using the "same paper" ..why Wix would opt for the lower setting (that can be compensated for with more media) and Purolator ..does not?
So can we assume that ..for example if we used a clicker bypass valve ...and it was ..let's say ..off by as much a 50-75% of design rating ..then everything should be okay since a 8-11 bypass can use the same paper as a 12-19 bypass filter??
[ July 23, 2005, 09:59 PM: Message edited by: Gary Allan ]
