Ran across an issue recently where we are losing much more material than anticipated during the etch process prior to Ti Anodize. It is a cylindrical shaft that is approx. 1.5 inches in diameter and the supplier identifies that will lose as much as .0001" per side during etch. This sounds...
A product we produce in specific configurations utilizes a splash lube planetary gearbox for speed reduction. The sun (nitralloy) and fixed ring gear (8620) are nitrided and the planets (9310) are carburized. In order to facilitate identification of lube refill we have recently added...
We have struggled with proper inspection methods for NPT threads created using NC lathe. We run into conditions where the L1 gage works as required but have struggled to determine a way to verify the L3 depth. There is no appropriate NPT gage and it is the feeling of some that it is proper to...
We have struggled with proper inspection methods for NPT threads created using NC lathe. We run into conditions where the L1 gage works as required but have struggled to determine a way to verify the L3 depth. There is no appropriate NPT gage and it is the feeling of some that it is proper to...
Will I see much, if any, speed rating advantage with the snap-in nylon cage / spherical seat versus a riveted, formed steel cage. Grease packed running in the mid 20k rpm. 12-14 mm ID. ABEC 1.
Also any ideas on gauging an advantage for same issue with speed by moving to an ABEC 3?
Thoughts or...
Am searching for fracture mechancs properties for 9310 alloy steel. Need for input to NASGRO. Any idea where to look? I have a couple of the easier to find properties but the crack growth properties are evading me. Any help is greatly appreciated?
BCK
I am reviewing the value of retaining a shot peen process on a carburized, low alloy pinion. The pinion is subjected to an initial shock load at start-up followed by a 1-3 sec duration steady load. Operating speed of 3-5k rpm and it must last in the neighborhood of 10k start cycles. The...
A QC person where I work was using the magnet test to determine if a washer supposedly produced from 301 SST was non-magnetic. I find that there is a 37-45 Rc hardness requirement that can only be achieved in the full hard condition. Am I correct in thinking that the material will be at least...
I have been tasked to determine if a small gear we purchase complete can be facricated with a lower core hardness than current. Current specification states a core hardness of 35-45 Rc. This small gear has a circular tooth thickness of nominally .06 inches. The current heat treat requirements...
We have a cast aluminum exhaust for a pneumatic turbine device. What would be the repercussions if it was exposed to < -200 F exhaust for an extended period? There is no cryogenic property information readily avaiable on aluminum. That should be an obvious sign. Thanks.
BCK
I have a small gear, 26 DP / 46 teeth, fabricated from 8620. A recent gear tooth failure problem was potentially linked to the existance of quench cracks. I question the observation only on the basis that only a single tooth was found to be cracked. Seeing as the entire gear would be submitted...
I have a small gear, 26 DP / 46 teeth, fabricated from 8620. A recent gear tooth failure problem was potentially linked to the existance of quench cracks. I question the observation only on the basis that only a single tooth was found to be cracked. Seeing as the entire gear would be submitted...
Have run into a rash of gear failures on a small gear (.06 tooth thickness approx.) that for years did not have any issues.
Current spec is 89-91 R15N effective depth of .008-.014. Core hardness 35-45 Rc. Measure at pitch line.
The gears are currently always coming on the high end on the core...
I am dealing with an Indian source for a small gear and they have expressed issue with the "Jomeny" content in the material we have chosen. They relate that they are using a material with low "Jomeny" and that they will need to acquire a material with higher "Jomeny" to achieve the core hardness...
I have a part from a non-domestic source that is being fabricated from 42CrMo in lieu of 4140. We recently discovered that the parts were being case hardened instead of thru-hardened. The core ran around 42 Rc, within specification, but there was a .009" thick case that was around 60 Rc when no...
Is there a such thing as a half harmonic of a whirl mode?
I am chasing a vibration issue that is dominant at a specific speed. It is not a fixed event that I can run through as it appears at a lower magnitude at lower speeds and increases in magnitude up to this specific speed. I created a...
We are experiencing cracking from the top corner of a keyway in a load carrying component that mounts to an rotating output shaft. The problem is that the cracking is occuring at 1/10th of the actual operating load during a controlled assembly prove out process.
The part is fabricated from AISI...
I am setting up a test where I will be monitoring a group of strain gages mounted at the root of a tooth on a pinion gear (gage type EA-06-015EH-120). The signal runs through a slip ring to the DA equipment. The loading cycle is about 70 hz max and will be concurrently monitoring 5 separate...
