That's the source, yes. Page 18 talks about 4200 MPa as the static load limit from ISO 76-1987. The limit for austenitic stainless would of course be much less. The plan *is* to limit the load to something like 0.05 of the basic rating of an equivalent carbon steel bearing. I have somewhat...
I can't see from your sketch where the thrust loads from the lead screw will be transferred to the frame. Depending on the design of this thrust bearing, it could be a significant additional source of torque.
The numbers are looking a lot better using rollers rather than balls (lower Hertz stress for a given diameter). Keeping the contact stress below 200 MPa, I figure a 1/2" diameter x 1/2" long dowel pin could hold ~ 90 N (20 lbf). I can build an arbitrarily large diameter bearing, so squeezing...
With due respect, it seems to me that you are grossly underestimating the engineering,experience and precision that goes manufacture of into modern rolling bearings.
I don't mean to minimize. I would dearly love if there were a commercially available solution for my application. Unfortunately...
Just pick up the phone
I wish it were that simple. Bitter experience tells me that most companies are not interested in engaging on a small custom job, even if I'm willing to pay a premium. If you know otherwise, maybe you can point me to a willing company?
You are really limiting the...
I need to spec a rolling-element thrust bearing in a fairly corrosive environment. Unfortunately I can't seem to find anything commercially available (400 series stainless won't work).
I am considering making our own thrust bearing. It should be easy to manufacture a cage from 304SS (just a...
Thanks for the notice. Sorry to hear about that. Roy's site is one of the best (free) resources on the web for mechanical engineers. Our profession would be better off if we each contributed a fraction of what Roy did to the commons.
Thanks tbuelna. I was hoping that the internal gear pair would have so much more load-sharing (at least 2-3x that of an external gear pair) that it would compensate for the extra support requirements for the internal gear. (I was imagining something like a belt drive, but with a fixed...
Thanks Dinjin. I looked at using the rack figures, but for the concept to work, it needs to show 2 or 3 x less bending strength than an equal thickness external spur gear.
If you have a spreadsheet available, can you plug in the following ratios and let me know what you get for contact ratio...
I am considering the design of a lightweight gearbox. I was hoping that by using an internal-external gear pair, I could get away with a much thinner gearset than I would with an external-external gear pair for the same torque. However I have not been able to find a good online reference for...
Right, it is only surface blushing now (no pitting), but it's only been submerged for a few months. The expected life is many years. I'll try the pickling route.
Hi all
I've run into a new problem. We often spec 17-4PH for hardened parts that must stay operate in a fresh water environment. For the first time, I machined the part using EDM before heat treatment (to H1025). After immersion, the EDM surface shows significant corrosion, as shown in the...
Telecomguy is on to something. After I googled "DC UPS" and "telecom", I came up with these two products which might be ideal (I still have to read the specs in detail):
Pheonix Contact
Siemens
Without a full set of specs, I'm leery about using power tool batteries or consumer power packs. Neither specify their maximum discharge current, and in the case of power tool batteries the manufacturers won't warrant their use in anything but their own tools.
The marine power pack lead looks...
