why would anyone want o-ring boss, isn't NPT far more common and useable? Which one seals better?

you can use these fittings with an O-ring:
http://store.summitracing.com/partdetail.asp?autofilter...700+115&autoview=sku

I just want to make sure I understand this right.

It is the spool not the body that is restricting. It is possible to get a spool with bigger passages.

How do you determine the best ones for your aplication? Are there a lot of possible options or only a few?

There are many options, I'm still waiting to sit down and call of the places. The previous pages described what people were drilling to, something like 0.035MM, I don't remember.

I was wondering about just asking the places what they thought would be the optimal amount of space for a passage, like how much is necessary for flow, and to what point when it becomes arbitrary.

I read somewhere that a -6AN ( - 6JIC ) thread is equivalent to 9/16-18 UNF - Here is an adapter at Mcmaster.com - 50925K451 about $2 ea

"Compact Extreme-Pressure Steel Thrd Fitting 1/4" Nptf X 9/16"-18, Unf-2A, Adapter, 6000 PSI"

This message has been edited. Last edited by: rkpatt,

Liveoily - Have you made any contacts on this yet ?

quote:

Originally posted by liveoily:
There are many options, I'm still waiting to sit down and call of the places. The previous pages described what people were drilling to, something like 0.035MM, I don't remember.

I was wondering about just asking the places what they thought would be the optimal amount of space for a passage, like how much is necessary for flow, and to what point when it becomes arbitrary.

Sorry guys, haven't been on here in a while. Actually been working a lot on my conversion and filtration setup.

Rkpatt, so I did make a bunch of calls. I called a few distributors of hydraforce, they didn't know anything, all they wanted was a part number. So I called hydraforce, talked to a backup tech for almost two hours! I asked a bunch of questions, laid out what I'm using the valves for and everything. She was really interested, told her all the basics, and she helped me out a lot, she said no one would probably help as much as she did because they're only looking for the big money sales (makes sense).

The bottom line is for me since I have a 12 valve cummins, which is a huge truck and goes through the fuel quickly, I wanted a valve that would have very little restriction like everyone discussed. I mentioned the SV10-31, and she said the SV10-33 is better. This didn't make sense at first because on the perfomance PDF of both valves, it looks like the 33 has worse perfomance than the 31, this is not the case, it's only that the graph doesn't keep going. She outlined how the spool actually turns and moves when it's energized and deenergized, and the 33 has FAR better flow through than the 31. It also relates to pressure drop, I don't remember exactly what she said about it, but that it's also better for the 33.

So now I have a part number, and the exact valve I'm getting for my truck, I'm calling a bunch of distributors on tuesday after the new year to get prices. I'll report back on what I find.

liveoily - It is interesting to know how differently those two valves operate . What part number did you come with ? - Thanks

quote:

Originally posted by rkpatt:
liveoily - It is interesting to know how differently those two valves operate . What part number did you come with ? - Thanks

In general, I was comparing the SV10-31 vs. the SV10-33. The 33 looks much better, even the lady at hydraforce was saying there is far less restriction from the spool.

She also stated it would not make a difference to slot or drill, I'm not even sure what the other guys were talking about after I learned how the valve operates. There are the ports (holes) in the aluminum body which allow the oil to pass in, the spool is energized and denergized, moving as this as done opening and closing other holes. You can simple request a different size porting (6T or 8T).

I believe, the part number that I will be going with (not definite yet, I'm still going to call a few other places tomorrow). would be along the lines of:

SV10-33-8T-V-12 or 24 (depends on if your system is 12 volt or 24 volt), then just put "DL" at the end, there are multiple options for this, that stands for lead wires, which to me, I'm just going to crimp a connect to a power supply and ground, probably a bus board. (Other options for the the connection are DL/W, which is leadwires with a weatherpack, DS which are just the metal spades sticking out, or ecoil, ER or EY) I will not be going with the e-coil, this sounds just not necessary, my valves will be on top of the engine and I live in san diego, very little moisture/precipitation here.

Hello liveoily,
I talked to another engineer and he also confirmed that slotting the aluminum body on the Hydraforce valves will help increase flow. Both the valve body and the spool cartridge are restrictions. You reduce the restriction the body has, which helps with better flow with the orfice on the spool cartridge. Anyway, the previous Engineer I was talking to has moved on, but the current one I am talking to is very interested in doing computer modeling of flows through these valves for wvo and also performing actual flow rate tests. To do this he needs some more details about what flows rates are required and optimal for various vehicles, pressures for IP for different engines (VW, MB, trucks) and oil temperatures and viscosities at the valves. He said he would provide me the with the results so that I could post them. What works for a Dodge Cummings may not work for a VW Rabbit, so if anyone can help with the gathering of this information it would be appreciated!! I hope we can take advantage of this opportunity. JEM Technical carries a wide selection of valves and many different brands of valves so if one brand or valve doesn't work the next might.
Have an Excellent Day!!
IRman

quote:

if anyone can help with the gathering of this information it would be appreciated

I amy be able to supply some of the info on flow rates, viscosity, temp. Please contact me by email.

Sorry InframanII, but your engineer is WRONG.

Let me rephrase that. If you drill or slot the the body you won't be able to notice any measurable flow benefits.

If you get a valve and look at it, you can see the restriction comes from the center of the spool. If you want that to be larger you have to get a larger spool which means you'll need a different series valve.

I don't understand why you guys keep beating this dead horse?
If you want more flow/less restriction you need a bigger valve. That is why they make bigger valves, for more flow.

quote:

Originally posted by roverhybrids:
Sorry InframanII, but your engineer is WRONG.

Let me rephrase that. If you drill or slot the the body you won't be able to notice any measurable flow benefits.

If you get a valve and look at it, you can see the restriction comes from the center of the spool. If you want that to be larger you have to get a larger spool which means you'll need a different series valve.

I don't understand why you guys keep beating this dead horse?
If you want more flow/less restriction you need a bigger valve. That is why they make bigger valves, for more flow.

Exactly, sorry to say it, at least in a little nicer way, but he's right. After you analyze the valve and really know how it works, it really doesn't even make any sense how they slot or drill the bodies. The bodies are just what holds the spool inside and has the ports for the connections. The spool ITSELF is what limits flow. This is exactly what I was talking about before, how the SV10-33 is most likely better than the SV10-31. These valves operate differently, the 33 allows FAR better flow.

Update: I'm having an engineer look into drilling more holes into the cage, this is the only thing that could increase the flow rate. He said they may have extras or extra cages they can drill to do this. I'll let you know what I hear.


So I found out, they can't drill them. The final part number I'm going with for my 12 valve cummins is: SV10-33-8T-V-12DL Also, for those of you ordering this valve, make sure you get the adapters because the aluminum bodies come with o-ring boss, the distributors sell the adaptors to NPT, it's very tough to find o-ring boss threaded fittings. If anybody needs help getting the valve or figuring it out, shoot me an email, I've spent way too much time talking to all these people now, but can help if you need.

Hi,
Have been researching the SV10-xx HydraForce (and other spool valves) for a couple of months now and came across this thread a bit late in the day.

Going by the published curves in the HydraForce catalog, I was a bit surprised to see the comment that the SV10-33 was considered a better performing valve than the SV10-31.

The SV10-31 looks like it has lower flow resistance in both positions than the -33, at least at the 1gal/min region of the graph. Not only that, but the -33 has approx. twice the flow resistance in the diesel position than it has in the SVO position (whereas the -31 has about the same flow resistance in both positions). Am I missing something here?

As far as the drilling/not drilling the housing is concerned, it should be recognised that most manufacturers (including HydraForce) say on their data sheets that the stated performance is for the valve catridge ONLY, i.e. does not include additional restrictions due to the housing. The only manufacturer I have seen that publishes their housing flow resistance curves is Parker. For the record, their (approximate) numbers are:
7psi @ 1 US gal/minute (08 housing)
4psi @ 1 US gal/minute (10 housing)
The curves are more or less straight lines in the 1 gal/min region, so you can pro-rate as required.

I would agree that the above information does not shed much light on how much the housing resistance could be reduced by drilling the ports, but it does show that the pressure drops due to the housing are of the same order as those due to the cartridge and would have a significant effect on the overall valve performace.

The only way to increase flow or performance, which isn't necessary with the 33 spool, since it completely moves, unlike the 31, is to drill the "cage" as the engineers call it, AKA the spool. However, they don't even offer this as a service, and I'm not going to completely change the flow with a valve that was designed and calculated with a different flow in mind.

I talked to a lot of people and studied the diagram. I ordered the 33 spool, but like the others, delivery is taking something crazy like 4 weeks. Make your own conclusions on what works best for you, because after looking into how the two spools operate, it makes much more sense to me to use the 33.

Also, one of the people I was talking to, was saying something about how the graphs simply don't continue. I asked something along the same lines of, 'well how come the 33 indicates a lower flow', or something like that inidcating flow. She was saying that it simply is a matter of extending the graph. I didn't completely understand how pressure drop relates to the veloctiy of the oil, but they agreed for my application, that the 33 was better.

So, liveoily, did you fine a best price for those valves? How much more are the 33's than the 31's? I have a Suburban 6.5L and it probably doesn't need the extra flow, but why not go first class if you can?! I'm also planning to run 1/2" WVO fuel line for the second tank.

quote:

Originally posted by liveoily:
The only way to increase flow or performance, which isn't necessary with the 33 spool, since it completely moves, unlike the 31, is to drill the "cage" as the engineers call it, AKA the spool. However, they don't even offer this as a service, and I'm not going to completely change the flow with a valve that was designed and calculated with a different flow in mind.

Also, one of the people I was talking to, was saying something about how the graphs simply don't continue. I asked something along the same lines of, 'well how come the 33 indicates a lower flow', or something like that inidcating flow. She was saying that it simply is a matter of extending the graph. I didn't completely understand how pressure drop relates to the veloctiy of the oil, but they agreed for my application, that the 33 was better.

I don't hold a strong attachment to either of the Hydraforce valves. But I think I should clarify a couple of things here:

1-The outer cylinder of the cartridge element is the cage. The spool is the metal slide inside the cage. They are not the same thing.

2-Several things limit the maximum flow rate in these valves.

The HF valves we are discussing are limited by the total force that the solenoid/spring can handle in maintaining the spool position (this is known as the 'shift limit').

The shift limit characteristic is determined by a combination of absolute fluid pressure and 'flow forces', which are a function of flow rate and spool geometry.

The reason why the max rated flow rates are different between the two valves is because the spool geometries are different and this results in different forces acting on the spool when hydraulic fluid is flowing. (If you really get into it, the direction of fluid flow also affects the shift limit rating - Parker publish some very nice graphs showing valve performance in all possible configurations for their valves.)

In the case of SVO fuel systems, the absolute fluid pressures are extremely low compared to the kinds of hydraulic systems these valves are designed for, therefore it is probably safe to extrapolate the pressure vs flow rate graph for the -33 as your contact at HF suggested. However, if you were running these valves at full (3000psi) pressure, you would risk not being able to shift the spool reliably above the rated flow rate of 5 gal/min.

Having said all that, comparing the max rated flow rates and the extents of the X axis scales is a bit of a red herring - I doubt that your fuel system even puts 1gal/min through the valve let alone 5 or 6. Which is why I made the original comment that it is more relevant to compare the psi drop at the lower flow region of the graph.

Ummm, yeah, so go with the 33, haha.

BK: I called like 5-6 distributors for the valves, I think they all quoted me at like the exact same price. I ended up ordering mine from the headquarters in CA, I think it was emeryville, I can't remember, it seemed as though they were most helpful/knowledgeable.

I went with viton seals, no manual over ride, no ecoil, with the 33 spool. I think it was 75 bucks per valve.

quote:

Originally posted by liveoily:
Ummm, yeah, so go with the 33, haha.

BK: I called like 5-6 distributors for the valves, I think they all quoted me at like the exact same price. I ended up ordering mine from the headquarters in CA, I think it was emeryville, I can't remember, it seemed as though they were most helpful/knowledgeable.

I went with viton seals, no manual over ride, no ecoil, with the 33 spool. I think it was 75 bucks per valve.

You're still missing the point - the -31 has the lower flow resistance at 1gal/min in both shift positions.

The pressure drops at 5gal/min and 6gal/min are irrelevent because your fuel system does not put that much flow through the valves.