Why not a plastic center tube with holes?

[slacktide_bitog]

There has been a big controversy about center tubes. Many people prefer the standard metal tube with round holes.

A recent trend is to replace the holes with thin slots/slits/louvers, but filters so equipped have many more of these than round hole tubes. More smaller holes vs fewer bigger holes. That said, people are afraid of the slots because they may not flow as well.

On the other end, you have ecores, which give the most flow! Plastic cage with only a few supports. Plenty of flow, but the media can blow through the cage because it isn't strong enough! Some newer ecores have more supports to reduce blowout.

So my question is, why not a plastic tube with round holes? All the advantages of ecore, the round holes people prefer, and this is definitely stronger than the plastic cage!

 

[sir1900]

There is really only one person who I know of is afraid of the slots.

 

[Garak]

I'm not sure how one example changing from holes to slits is a trend. Baldwin and Hastings have used them all along.

 

[CT8]

The cheese grater design has been used for decades in some of the premium filter brands.

 

[Sayjac]

Or course the whole premise 'assumes' there is some issue with current louvered designs used by manufactures and that filter flow in general in pc use is somehow an issue. Haven't seen either proven or posted here. As Zee often posts, engines oiling system is ~15x times more restrictive than the oil filter.

So no tube design or filter flow design controversy for me. Just mythical legend posted and repeated by a very small minority.

 

[Johnny2Bad]

The round hole design is the least efficient as far as area available for flow; the louvered design inherently flows more oil.

Certainly the final flow rate is dependent on exactly how much area is perforated, but if you perforate the round hole design to the maximum allowed while retaining the minimal sufficient rigidity for robustness, and do the same for the louvered design, the round hole loses.

 

[KGMtech]

I work in the metal stampings industry, automotive stampings.

From a process perspective, piercing slots is far easier than making holes in metal. The tooling is cheaper and requires less maintenance.

There is no need to worry about loose slugs (hanging chads anyone?) on the tube with the slot design, and because the material gains some depth and a bit of work hardening, it might be slightly stronger ~ however the need for this strength is nominal at best.

So IMHO, slots are better. Take that anyway you want )

 

[goodtimes]

Sounds like a good idea. The Denso made in Japan had a plastic cage center tube also. Maybe it boils down to altering manufacturing processes already in place. It also may mean attacks from competitors about plastic inside instead of metal. I like the round holes because it's pretty clear to see if they are open, and no one has ever shown any that weren't.

 

[robo339]

Originally Posted By: sir1900
There is really only one person who I know of is afraid of the slots.


True story but if you cry like a baby long enough someone will go crazy and believe it

 

[ZeeOSix]

Originally Posted By: KGMtech
So IMHO, slots are better. Take that anyway you want )


Louvered slots are fine ... IF they are punched open correctly. I've seen some louvered center tubes where the slots are barely opened up. Then I see center tubes with very open louver slots, which is the correct way to do it.

Even if there are a lot of louvers, if they are only opened up 0.010" wide, it makes me a bit leery to use those vs ones that are opened up much more.

These are examples of nicely opened louvers. Now imagine those with only a paper thin slit instead.

 

[Merkava_4]

Originally Posted By: ZeeOSix
Louvered slots are fine ... IF they are punched open correctly. I've seen some louvered center tubes where the slots are barely opened up.


That's why I like holes better. The holes are either open or they're not. Less room for manufacturing error.

 

[WellOiled]

Originally Posted By: sayjac
Or course the whole premise 'assumes' there is some issue with current louvered designs used by manufactures and that filter flow in general in pc use is somehow an issue. Haven't seen either proven or posted here. As Zee often posts, engines oiling system is ~15x times more restrictive than the oil filter.

So no tube design or filter flow design controversy for me. Just mythical legend posted and repeated by a very small minority.


+1

Properly designed louvers or holes, makes no difference to me. The metal tube keeps the media from having a complete blowout. The hole or louver surface area will generally exceed the area of the filter mounting nipple by a wide margin.

eCores take the concept to the limit by having the near perfect drain field for the media. The risk being media blow out. They also have a nitrile combo valve which could be problematic.

I confess, I have an AC Delco PF1250 on the truck right now. I will post the results one way or the other.

 

[goodtimes]

The issue was more about if the louvers are made right, not if the design is right. There is a difference between making a hole and removing the plug completely, and making a hole only enough so there is a slit opened, and the plug is still present. Takes a lot more precision and equipment maintenance to make louvers uniform I would say.

 

[WellOiled]

goodtimes - The move from holes to louvers may have been for cost reduction purposes and the ease/speed with which a louver could be formed.

 

[ZeeOSix]

Originally Posted By: goodtimes
The issue was more about if the louvers are made right, not if the design is right. There is a difference between making a hole and removing the plug completely, and making a hole only enough so there is a slit opened, and the plug is still present. Takes a lot more precision and equipment maintenance to make louvers uniform I would say.


I agree ... making louvers correctly entails more fineness in the manufacturing process than punching out holes.

 

[slacktide_bitog]

Another good idea would be a metal cage. The plastic ecore cage isn't strong enough, but maybe it would be OK if it was made of metal.

 

[WellOiled]

Originally Posted By: slacktide_bitog
Another good idea would be a metal cage. The plastic ecore cage isn't strong enough, but maybe it would be OK if it was made of metal.


In my view, the 2 remaining problems with eCore are 1) the end caps may not be glued very well and 2) the combo valve may not function as well or as long as needed.

As far as media blow outs are concerned the window size is much smaller and I think Champ Labs is using a bit stiffer media than before. We don't hear about this any more.

The new center core is pretty strong. I don't believe it can be crushed in normal use. I certainly could not crush it with my hands.

 

[MrkofXcellence]

The ACDelco ecore filters don't use the combo valves fortunately. However, somebody recently posted a picture around here where the endcaps of the ecore filter totally bent around the leafspring at the end of the can, and this was one of the new Delco e-cores with the poppet bypass valve. I worry about the proximity of the media to the can on the circumfrance of the filter. There is very little clearance between the can and the media.

 

[Sayjac]

Quote:
The ACDelco ecore filters don't use the combo valves fortunately.....

AC Delco filters for newer GM models don't use a combo valve, they use the previously noted separate poppet type bypass. ACDelco ecore filters for earlier/older GM vehicles don't use a combo valve either because they have engine block bypass.

However 'some' ACDelco ecore filters do use combo valves, the PF53 is one such example. It is the 3614 equivalent and used on other than GM vehicles.

 

[yvon_la]

Media end cap on fleetguardbig rig filter are plastic . gm e-core is plastic center tube. Plastic exist. For high temperature application . but there is an urbane legend that plastic is bad .dont get mewrong, itcan be bad . but ifyou follow torque recommendation (and no , half a turn wont cut it, manufacturer have. To supply propertorquein newton meter ot pound feet . ifthis is rezpected,plastic is likely a better choice ,