So, I guess I was right, that other 275 post thread is all about bashing kerma and bosio to set the stage for nicktane. Let me explain the meaning of the word "crude".
How did you measure to 4 significant figures accurately?
the bosio edm is purpose-built for injector nozzle manufacturing, and has the ability to change the size of the hole profile during the edm drilling. in other words, the inner diameter is larger than the outer diameter in some cases, and there's a chamfer added to the inner surface at the flow entry, just like the Bosch.
The flow numbers listed above for the Bosio are all wrong. Every Bosio nozzle is flowed in ml/min of test oil at 100 bar and 40°C with Shell oil V 1404 according to ISO 6584 comma 3 sub comma 431 test standard using a very expensive state-of-the-art machine that was built especially for Bosio. The flow tolerance is set to within 1% for the sprint, 0.5% for the Powerplus, and 0.2% for the race. The machine can hold tolerance less than 0.1% if needed. This oil flow is measured in the same direction as the normal flow of fuel during use an a car, IOW, from the inside out.
I wonder how the Nicktane measures nozzles. When they talk in liters per minute, that tells me compressed air at 50 psi, which is the "golden standard" with the truck nozzle guys. They connect a rubber hose to the outside of the nozzle tip and flow air in the reverse direction, in the tip and out the entrance. Adjust the air regulator to 50 psi, and guess the height of the metal ball bouncing up and down in the flow meter and "call it". One prominent vendor was quoted in a diesel mag as saying "we like to get the flow within one" (liter per minute of compressed air at 50 psi) For reference, we are talking about roughly 20 liters per minute for sprint 520 nozzles using this method. "within one" is +/- 5% if you can get it consistent each time, not counting the error from the flow gage, temperature differences, compressible medium, etc.
At Bosio EDM is cut into a fresh nozzle with no hole using CNC edm. tolerance at this stage is +-6%, which is slightly looser than the finished bosch. There are 3 steps to the "honing" after the initial EDM. initial flow measurement/cleaning, hydro-grinding, and cleaning/verification.
The hydro-grinding is done using a media with the same viscosity and flow characteristics as diesel fuel, but it contains proprietary sub-micron sized abrasive material suspended in the oil. The flow is measured in real time as the nozzle is matched to the target flow. there is very little material removed during this process, which intended more as a de-burring than anything.
THis is the way Bosch nozzles are made at the Bosch factory, and the process is state-of-the-art.
WHen the bosio nozzes are packaged, a heavy grease type material is applied to the inner and outer surfaces to stop corrosion. That's what is seen and it doesn't have to be cleaned for the nozzle to be useable as it is soluble in diesel fuel.
EDM burn? it's in the wrong place on the nozzle. seems fishy.
I'll have to assume the nicktane manufacturing and test procedure is similar to what the truck guys have been doing for years:
EDM machine is typically one that's been previously used for medical equipment, and drills one hole at a time. The "real deal" costs about 400 grand and none of these guys can afford that. They take a genuine Bosch nozzle, and line up the machine with each hole individually, and drill with the edm electrode to make the hole bigger. There is no ability to vary the profile through the depth of the hole, and the leading edge tends to be rough. You can make the holes any size you wish, however. Extreme care must be taken by the operator, because even the 0.5 degrees misalignment in any axis will destroy the integrity of the original hole. It's not uncommon to see "twinning" or a figure eight on the inside of an aftermarket EDM'ed nozzle. When this happens, the operator will just pretend it's all right, and send it on to the customer anyway, because he doesn't want to eat the cost of a new nozzle, and if it smokes: "it's a high flow nozzle, what do you expect"
The extrude honing process uses a much higher viscosity media than the test oil, and it is an iterative process. Flow is measured, then the operator estimates the flow time based on the media used and the operator's experience. The cutting media is forced through the nozzle for the calculated time, then the nozzle is cleaned and the flow measured. If it's close enough, done, if not, it may be cut again with a different lower viscosity media. The heavier the media, the more it cuts. If the operator overshoots one nozzle, he may just ignore it and go on to the next one, or try to bring the others in line, which means increasing the flow on the other 3 to match. But that's more work, and unless the customer is a very special one, or paid extra, errors of a few percent are just considered part of the game.
Extrude honing is not in itself bad, because every major manufacturer uses some form of "hydro-grinding" to polish and deburr the flow passages. But this hydrogrinding is only for the last 5% or so of the flow, and to match the nozzles to a flow standard. The problem comes from trying to cut too much. the seat of the needle gets cut, and the needle won't seal as well between injections. This causes a nozzle to not chatter and it could even stream fuel or bleed down between injections.
It also affects the outside if the hole in a drastic way. Here is an example of a nozzle that's been cut far too much
This is my definition of "crude" It's a relative word, and I think it's appropriate in this case.
I'm sorry if that word offends you, Nick, but I don't think it begins to balance out all the 275 posts in that other thread, laying the groundwork for your new product release, savaging both the competing product and me personally.
Ain't gonna happen.
