MASSEY (Mechanical) 12 Feb 09 13:17
Looking for a gearmotor that will automaticaly switch to slower speed to increase torque when higher torque is required.
Then return to higher speed when lower torque is required.
I assume that amp draw may trigger the speed switch. I have seen these used...
The Brookhaven National Labs have some very useful procedures available online like this one.
http://www.bnl.gov/esh/shsd/sop/pdf/IH_SOPS/IH62480.pdf
There are several more also.
Looking for a gearmotor that will automaticaly switch to slower speed to increase torque when higher torque is required.
Then return to higher speed when lower torque is required.
I assume that amp draw may trigger the speed switch. I have seen these used in applications, but I do not know the...
Some conveyor pulleys that have been in use for some time have spiral wrapped lagging made of SBR rubber. The lagging is reverting which is depositing unwanted substances on adjacent surfaces.
The belt that is driven by the pulleys has a PVC backing.
Do you know of a way to stop the reversion...
I'd go with number 2 also, and if the bosses don't insure your project perhaps you'll be prepared for RDK's last post with this job as your first project. However this would open a new can of worms, but it may turn out to be the best solution because the customer will get what he needs and your...
EnglishMuffin:
Thanks, I read the thread listed above. It sure sounds like you and the other posters know what you are talking about.
Thanks for the insight.
That is to say that if the load is rotating it is no longer static, but if the load is static then the static load rating should not be exceeded.
And although the dynamic load may be larger than the static load rating. The load must continue to be dynamic, and if it stops rotating then the...
EnglishMuffin:
It is my understanding that Dynamic loading should never exceed the Static load rating. If rotation is occurring the load would probably be considered dynamic unless it is rotating very slowly.
I would be interested in seeing some reference from manufacturers stating that the...
This sounds like a good application for brgs. provided by igus or some other similar manufacturer. igus link is listed below.
igus.bdol.com/drylinr.asp
Good Luck!
I agree with electricpete, when we speak of "life" calculations, they always refer to rpm or rotating speed.
Certainly static rating is vitally important and cannot be exceeded, preferably not even approached.
An important note comparing static vs. dynamic however is that when more than one...
...and then there is the question of 'seals' are your 'normal' bearings sealed or not. If so what type of material is the seal made of?
I would suggest you contact a reputable bearing manufacturer with your 'normal' operating conditions. And let them suggest the bearing configuration and they...
Bad news chrispe:
For these small bearing series the max axial load should not exeed 0.25 of the static load rating.
In other words if you want 300 lbs. axial load capacity your static load rating should exceed 1200lbs. Which starts somewhere around an R14. Or metrics: 6005, 6204, 6302, etc...
Perhaps you can have the whole assembly custom/special made at a roller manufacturer such as:
www.pcimfg.com
Roller manufacturers are accustomed to meeting special design requirements on a daily basis, plus there is the added benifit of a warrenty, usually.
Good Luck.
toolmantwo:
I disagree that all CAD drawings look the same. I think I know what you are saying and in a sense it is of course true. However, there are alot of added attention to detail that can make one CAD drawing 'look' better than another.
For example: text positions, leader angles...
How are the mechanical properties of Nylon 6/6 affected due to moisture absorbtion.
I understand a typical value may be 3% moisture absorbtion by volume. How does this affect the tensile, yield, compression strengths?
Conversely, if in a very dry environment will the Nylon become more brittle...
