Measuring at the tip may fool you, as the old style heats the tip much hotter than the duraterm which may actually put out more heat by heating evenly all the way to the root.
I believe glow plugs are designed so the tip is the hottest since that is where the heat is needed. A glow plug that is hotter elsewhere (other than the tip) has something wrong with it.
http://www.autoserviceprofessional.com/article/92559/prevent-diesel-engine-damage-with-bosch-duraterm-glow-plugs"the regulating coil keeps the heating element within the 1,832-2012 degrees F (1,000-1,100 degrees C) optimal temperature range, preventing engine damage due to over voltage or overheating."
I believe Bosch when they publish a graph of their glow plug temperature and do not need to measure one to verify. I know just by looking at the color of the tip (yellow/white hot) that it is much higher than 900- 1000 F which is red/orange.
Nice theory, but duraterms don't glow that bright.
Even if it were out of spec at 3%, I'd still show 997 instead of 1000. If you point it at a light bulb, it is a bit funny aobut how many layers of glass it's going through.
They are probably graphing the calculated temp of the nichrome? wire inside the casing.
You can easily see that the tip of the duraterm plug is not as hot as the regular one.
The inconel shell would be malleable if it were getting that hot
Heat Treatment The alloy is not hardened or strengthened by heat treatment.
Forging Forging should be done in the temperature range of 2250 F to 1900 F.
Hot Working Hot work in the range of 2250 F to 1600 F. Avoid working in the range of 1400 F to 1000 F as the alloy is apt to thermal crack in that region.
Cold Working Cold forming may be done using standard tooling although plain carbon tool steels are not recommended for forming as they tend to produce galling. Soft die materials (bronze, zinc alloys, etc.) minimize galling and produce good finishes, but die life is somewhat short. For long production runs the alloy tool steels ( D-2, D-3) and high-speed steels (T-1, M-2, M-10) give good results especially if hard chromium plated to reduce galling. Tooling should be such as to allow for liberal clearances and radii. Heavy duty lubricants should be used to minimize galling in all forming operations. Bending of sheet or plate through 180 degrees is generally limited to a bend radius of 1 T for material up to 1/8" thick and 2 T for material thicker than 1/8".
Annealing Annealing following cold working may be necessary. The annealing temperature is 2100 F and the alloy should be rapidly cooled through the range of 1400 to 1000 F to avoid thermal cracking.
http://www.autoserviceprofessional.com/article/92559/prevent-diesel-engine-damage-with-bosch-duraterm-glow-plugs
"the regulating coil keeps the heating element within the 1,832-2012 degrees F (1,000-1,100 degrees C) optimal temperature range, preventing engine damage due to over voltage or overheating."
I believe Bosch when they publish a graph of their glow plug temperature and do not need to measure one to verify. I know just by looking at the color of the tip (yellow/white hot) that it is much higher than 900- 1000 F which is red/orange.
We can only see the sheath Chief, not the element.
Like I said, Nichrome wire element, 601 Inconel sheath.
Cred to Whunter@peachparts.
http://www.autoserviceprofessional.com/article/92559/prevent-diesel-engine-damage-with-bosch-duraterm-glow-plugs
"the regulating coil keeps the heating element within the 1,832-2012 degrees F (1,000-1,100 degrees C) optimal temperature range, preventing engine damage due to over voltage or overheating."
I believe Bosch when they publish a graph of their glow plug temperature and do not need to measure one to verify. I know just by looking at the color of the tip (yellow/white hot) that it is much higher than 900- 1000 F which is red/orange.
We can only see the sheath Chief, not the element.
Like I said, Nichrome wire element, 601 Inconel sheath.
Cred to Whunter@peachparts.
What's are you trying to say???
To the OP: Sorry for the thread drift. Did you get your glow plugs replaced?
What's are you trying to say???
That the quote from Bosch is in complete agreement with my earlier statements, because I am in fact correct.
What's are you trying to say???
That the quote from Bosch is in complete agreement with my earlier statements, because I am in fact correct.
What, like the Inconel sheath is gonna cut 1000F off the nichrome? If the nichrome is at 2012 F, the Inconel sheath, being in good contact surrounding the nichrome is gonna be the same temp. Where is the heat gonna go except outward? If the glow plug can't get the heat out from the nichrome, it's gonna burn out dude.
Just because your IR thermometer says it reading 1000 F does not mean it's correct. I pointed out that IR thermometers are not accurate when measuring light color objects. Furthermore, most IR thermometers measure up to 400F only. The more expensive ones measure only up to 1000 F. I'd suggest you read up on the spec of yours.
1000 F is blood red hot, not hot enough to light off a diesel. I remember reading that minimum is 1700 F.
Here's a chart on color of hot object and temperature
http://www.processassociates.com/process/heat/metcolor.htm
What, like the Inconel sheath is gonna cut 1000F off the nichrome? If the nichrome is at 2012 F, the Inconel sheath, being in good contact surrounding the nichrome is gonna be the same temp. Where is the heat gonna go except outward? If the glow plug can't get the heat out from the nichrome, it's gonna burn out dude.
Just because your IR thermometer says it reading 1000 F does not mean it's correct. I pointed out that IR thermometers are not accurate when measuring light color objects. Furthermore, most IR thermometers measure up to 400F only. The more expensive ones measure only up to 1000 F. I'd suggest you read up on the spec of yours.
1000 F is blood red hot, not hot enough to light off a diesel. I remember reading that minimum is 1700 F.
That's what you said, but you didn't have much to back it up.
Mine was not cheap,is accurate to +_1.5% above 950F, more at lower temps, and has never once produced a dubious reading.
Autoignition of diesel#2 is about 494F
You might want to do a lot more reading, or some experimentation.
If it did really take 1700 to even light diesel, how wold our EGTs ever get down around 300?
See the white stuff? the only part of the element in contact with the sheath is at the tip, to provide a ground path, and measurement for the autoregulating feature.
1000 F is blood red hot, not hot enough to light off a diesel. I remember reading that minimum is 1700 F.
At 1atm. If you increase the pressure 23 times, you now have a partial pressure of around 480% oxygen in the pre-cup. Even if the pressure increase doesn't cause a significant temperature increase, the pO
2 has effectively lowered the auto-ignition temperature of the fuel.
Oh, I just looked it up. Auto-ignition of diesel fuel varies hugely from 210 °C to 400°C depending on composition.
I watched the propaganda video from DieselRX about there glow plugs the other day and wondered about he tip vs length heating.
I didn't wonder much as I've never had problems with either bosch or beru glow plugs in a VW-D, but I did wonder.
I did not start this thread. It was started by a moderator by taking parts from another thread while leaving some important parts out which screwed up the context. I am not posting to this thread anymore since I'll just be wasting my time.
Doesn't bother me any. Figured you were wasting the op's time in the other thread, so I split it.
Not much was lost, it was mainly so the discussion could continue between you and wolf_walker.
I did not start this thread. It was started by a moderator by taking parts from another thread while leaving some important parts out which screwed up the context. I am not posting to this thread anymore since I'll just be wasting my time hate being wrong.
Fail, but I fixed it for ya.