Pipe sizes and fittings.

[fatdaddy]

Virtually all the stuff you buy from the US will have JIC  or NPT threads.
In the UK we traditionally use BSP [some BSPT] but have used a lot of METRIC for the past 10 years. Most rams and valves you buy in UK will have, at least the option of, BSP.

Confusion is easy [this isn't strictly 100% technicallycorrect but explains well]............ if you are talking UK and you say 3/8 BSP that is a fitting that will be used with a hose that has a 3/8 bore. If you are talking US and you say 9/16 JIC that is a fitting that had a 9/16 thread form NOT related to a specific hose bore.
Unless you are just building a 12volt slow system you want to use fittings and hose that will give you a 3/8 bore all the way so regardless of what thread form you are using that is what you need to specify. If you are not SURE you ask "I want to go from this to this [show him the parts] with fittings and hose that keeps a 3/8 bore all the way".................

BSP [paralell or taper] thread looks like this



This is a 3/8 BSP fitting. Notice the concave cone and the flat shoulder for a dowty seal.
BSP threads are used in hose fittings and in port fittings [as you would screw into a valve block]. With a port fitting you need to use a Dowty seal to seal the oil pressure.

JIC looks like this



This is a 9/16 JIC fitting. Notice convex cone and no shoulder.
JIC is mainly only used for hose fittings. Port fittings will be NPT, this is tapered and you use PTFE tape on the thread to seal the oil pressure.



On right is a standard US inline check valve [ 3/8 NPT], on left a 9/16 JIC fitting the size US will supply for use from dump to rams.


Take a standard US dump valve. The port size will be 3/8 NPTF. The fitting you will get in a kit to go there will be an elbow with 9/16 JIC on the other end for a hose.

If you now run a hose from the dump fitting to a UK sourced shut off [on an accumulator for example] you will us a 3/8 bore hose [same size as the dump hose you get in the kit BUT be aware that they sometimes use lower pressure hose for dump hoses to save some cents!].
At the UK valve block you will have BSP sizes. You now have a choice of using a BSP hose fitting on the end of your hose from the dump [so you change everything from the on to BSP] or using a tee to the acc valve that has BSP on the branch and keeps JIC for the hose run. Personally I like to use JIC where ever I can.

Rus. I suspect that you have used a 3/8m to 1/4m [1BP0406] fitting in your shut off block, then a 1/4 f-f-f tee [ZFB04] with two 1/4m-1/4m [1BP0404] fittings ?
Really you should go for 3/8mBSP-9/16f JIC [1BJP0609] in the block then a 9/16 JIC m-m-m tee [ZMJ09] and use 9/16 JIC swage fittings with 3/8R2AT hose.


 

[Chops]

Here's the missing image from Iains post

Thanks Andy  didnt notice that 

[rudey]

Im slightly worried ive got the 1/4" fiitings now not the 3/8" fittings, will these have a dramatic effect on the system performance of the cars lift / drop (bearing in mind i dont wanna rag it and break it!!)

[fatdaddy]

i'm sure the fittings on your lock valves are 1/4.... but you can just swap them for 3/8 at this stage cant you ?

They will have an effect, dramatic............. maybe not quite that visually
but accumulatively......
the restricted bore will, increase battery power consumption, slow response to switches, delay accumulator reaction to bumps.
So not dramatic but if I were you {and at this early stage of build} I would go with 3/8. 

[fatdaddy]

1/4 bsp and 3/8 bsp male fittings




notice the difference in bore size..............................then think of that difference running the length of your beast!

[rudey]

see what your saying.... ill get em changed

[rudey]

just been checking again, getting apprehensive here, everything on the system is 1/4" fittings, hoses, pump set up etc... so assumingly 1/4" off accs etc should work? if i was to put 3/8" off accs how can that make any difference throughout the system as it would be like water tap to hose pipe nozzle? where everything is under increased pressure so the reaction would not be the same? or am i looking at it wrong? the hydraulic fluid can only travel through any diameter at a certain rate surely... (plus it will cost a small fortune again at this point to change everything??

[fatdaddy]

Didnt realise you had got as far as hoses Rus.......
looking at your pics [one you describe as scruffy with hoses coiled up] I'm sure they are 3/8 hoses ?
The lock valves look like they are 3/8 ported to me and the tee's on them look like 3/8 but with 3/8 to 1/4 fittings.......... anyway if you have hoses already then you are a bit stuck really.

Any hydraulic system needs to be optimised throughout, so every fitting/hose/bend/adapter needs to be correct............ so you are right in saying if some of it is 1/4 the rest might as well be to a point although less restriction is still better than all restricted.
AS to what difference it is going to make in practise, to be honest i'm not sure as i've never used 1/4 in a system over 12volts or with accs on a car as long as yours.

If I'm right in assuming you have what you have now cos it was specified by a Hydro professional that you showed all the bits to............... then here is why he was RIGHT to give you what you have but also an explanation of why "normal" people dont understand what our systems need and why you will nearly always end up with an um optimised Lowrider system even if it is an optimised hydraulic system.
 


[I'll be posting this bit at a time for a couple of days]

[rudey]

All the hoses are stamped up 3/8" and are the ones which came with the black magic kit which i bought off chewy, speaking to chewy, thats what grays Lincoln is running as its the same kit, so im surprised its been supplied at 1/4" if thats inificient for a system (especially coming from the U.S)
i guess if the hoses are 3/8 and the fittings to the end are 1/4" its gonna be the same  reaction across the board, Grays cars works ok from ive seen, i know i dont want to break my car but i want it to at least move...

I hate cars....

[fatdaddy]

that gets more confusing as the US doesnt use 1/4 fittings [bsp that is] !.............. They will be JIC as the dump hose fittings.
3/8 hose they do, and thats what you should have.

tell me why you think the fittings are all 1/4 ?

did you look at http://uklows.com/forum/index.php/topic,2213.0.html

If you have 1/4 bsp there is something wrong............... if you have US supplied hoses they WILL be
JIC , if they are the same size as your dump hoses your OK . They may be marked #6 and should have a 9/16-18 thread BUT that's referring to the thread size NOT the bore size.


I started this by saying that basically yanks talk about hose/fitting sizes related to thread size and we talk about them related to bore size............I'm now guessing that this is still causing confusion in this case. Look at the pics in the above link and see if you have BSP or JIC fittings.

[rudey]

OK... out of curiosity, ive just cracked the joints on the pump etc, they are all 1/4" bore, so i'm guessing changing the rest to 3/8" will be pointless at this stage as it wont flow any faster out the pump?? The kit i believe was supplied via Stevie Dixon so i would have thought he would have picked this up as he put kit together ... nothing is ever simple eh...??

[fatdaddy]

you've got 3/8 hose so the rest shouldn't be far off......................... and BM normally, know what they are doing.

[Chops]

Rus, in the pic below, the elbow sticking out of the dump AND the hoses look like 9/16 JIC to me.
The fittings sticking up out of the acc elbows look like they are reducing nipples from what I can make out. Do your hoses fit the dump elbows and are they all that size?

[Chops]

Just been out to the workshop to check.

From left to right, on top of the dump block-1/4 BSP nipple, lower- 3/8 JIC with hex nut,  screwed into the dump- 9/16 JIC elbow and far right- 3/8 BSPT barrel nipple (the last one is 150 lb not hydro but the thread is correct for 3/8.
The 9/16 JIC fitting is approx 7mm bore and is the standard size found throughout lowrider systems with 3/8 or #6 hose

[fatdaddy]

its the WTF that look wrong to me as well Andy but i think now its maybe just the way they look..............your 1/4 fitting looks the same size as the barrell nipple in the pic.