I haven't heard back from Staubli, however I did my own research and here is what I found:
It is possible to use the Staubli Socket, metric male thread Part# SPH 03.1410/BA/L/KR with Cooper washer as shown in this picture below, however, please note that this is connected to a distribution block with a total of 3 hoses supporting the distribution block (and the distribution block itself might be secured with a bolt through that through hole on the distribution block). This means the Staubli socket will not be subjected to any outside push/pull/sideway force.
Mounting this Staubli Socket, metric male thread Part# SPH 03.1410/BA/L/KR directly to the FRONT Brembo Brake Caliper is a different story because:
a. it will be subjected to many forces from the jolt from the road bump (remember the caliper is NOT suspended/unsprung weight so any force from the road bump is directly transferred without any suspension to absorb the shock).
b. it also have to withstand the side by side forces when the steering turns (plus the whiplash effect of the hoses and also the other Staubli plug connected on top of the Staubli socket)
c. Please take a look at the drawings below:
you can see that the "L" dimension is only 8mm and not all of those 8mm is threaded shape, meaning it will only have about 5mm of thread that actually hold (clamp) everything. Compare this to a normal banjo bolt which usually have 10mm of thread available and about 8mm of them engaged. this means the clamping force from the torquing are divided only among 5mm of thread. This put more stress on both the Staubli Socket Connector and the thread inside the Brembo Caliper itself !!!
Plus, both the Staubli and the Brembo were made from aluminum so the chance of this thread fail is higher.
Aluminum main weakness is metal fatigue and it will break without warning... so if you are using aluminum, you better have to design it properly and based on all the above, I just worry if after thousands of mile of hard driving and the aluminum threaded section (below the hex) just snap due to metal fatigue
Now you can always purchase the Staubli Socket in Titanium (stronger thread, right?), Part# SPH 03.1410/BA/TI/KV, however this means the 5mm thread engage inside the Brembo Aluminum Caliper will have higher chance to break/stripped before the Staubli socket during torquing, but of course this is worse... since you don't want the thread in your Brembo caliper to be broken.
d. Please take a look at the picture below:
I don't know how other Brembo caliper banjo port shape, but this is the picture of the banjo port on my stock Brembo Stylema caliper.
As you can see, it have a "higher/protruding" ring (marked by red arrow). That higher ring help to "crush" the cooper washer, but at the same time, that means it also might crush the O-Ring of the Staubli Socket Metric Male Thread SPH 03.1410/BA/L/KR, because instead of grooves to accommodate the O-Ring, it actually protrude. I did not have the measurement of the O-Ring, so there is a small chance that the O-Ring of the Staubli Socket have larger Internal Diameter than this protruding ring of the Brembo Stylema caliper port, but I doubt it...
so this means, we better use cooper washer, right?
well, take a look again at the drawing above, where it say "14/FLATS" indicating the largest diameter for Hexagonal shape is only 14mm... compare that to the regular Banjo Bolts which have the head diameter of around 15.5mm.
Why this matter? because this again means those 14mm Hexagonal shape of the Staubli Socket have small area to push/clamp the cooper washer and thus more stress compare to a regular banjo bolts (more area to press).
And regular banjo bolts are made of steel and in my case ProTi Titanium Bolts while this Staubli Socket is made by aluminum.
Based on all the above, I rather use the Staubli Banjo Connector, take a look at the drawing below:
First, Staubli take precaution due to aluminum material by making the "thickness" of the banjo to 13.2mm (instead of the regular 10mm for stainless steel).
This is why, it will need LONGER banjo BOLTS.
Second, since this will follow banjo standard size, the inner and outer diameter of that banjo area will be FLAT and about the same diameter as the cooper washer, allowing for more uniform pressure.
Third, it will allow the use of a MUCH STRONGER Stainless Steel or Titanium Banjo Bolts to provide the clamping force.
Forth, those Stainless Steel or Titanium Banjo Bolts will also have the full thread of 10mm with at least 8mm of the tread engage to the thread inside the Brembo Caliper (vs only 5mm if we use the Staubli metric socket).
3mm more thread engagement might not seemed to be much but if you use, percentage, that 3mm extra means 160% more thread engagement vs. the 5mm. (so percentage wise it is a lot).
Because of all the above, even if it is possible to use cooper washer with Staubli metric socket to connect it directly to the caliper, I will prefer the Staubli "banjo" style connection instead.
EDIT: also using the Titanium material will only overcome the "strength" and "metal fatigue" issue of the aluminum, but still have other weaknesses as describe above, not to mention much higher price and it also weight more than aluminum
SPH 03.1410/BA/TI/KB (Titanium Socket) weight 16 grams
SPH 03.1021/BA/L/KR/BJ (Aluminum Banjo Style Connection) weight 14.2 grams
RE-EDIT:
Actually Staubli have a different more compact (and more expensive) quick couplings connector model the CBR02 series and from their PDF catalog it shows that
the Maximum pressure for the CBR02 is PS (bar) 300, however the pressure is DOWNGRADED A LOT if using Cooper Washer as seal:
Version with copper washer sealing maximum pressure is only (bar) 120
