|
|
|
|
|||||
|
||||||
From: ahmet erkan (no email)
Date: Wed Nov 23 2005 - 14:36:59 EST
>A 1 1/2 " shaft has an area of 5.31 sq.in. A 7/64 pin would be enough
the
>hold the shaft against the washer against the seal, and the 7/64 hole only
>weakens the shaft by about 3%.
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Hi Peter,
1.5" shaft should have 1.77 sq" cross sectional area, and a 7/64" through
hole should reduce it by 9.3%. BTW : Are you sure this is the proper method
to predict the amount of strength loss of a shaft when a orthogonal hole is
drilled through it ?
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
I passed on the information and also Norm's comments to one of the
mechanical engineers in the plant, here is what he had to say :
in compression the .109 dia hole reduces the strength of the shaft to about
91% of it's original strength.
Ryan. It is probably ok in compression and tension.
Ryan In Torque, it is significantly reduced. About 45% to 55% of it's
original strength.
Ahmet Erkan/R... Wow
Ahmet Erkan/R... Torsion is the main component
Ryan. It does depend on the amount of torque but taken to failure, the shaft
fails a lot quicker with the hole in it. At the hole, you have essentially
split the shaft into two semi-circles which is much weaker than a cylinder
Ryan. If you knew what torque you were inputing, I could tell you if it
would fail or not.
Ryan. I agree with the above poster, I would not drill a hole of that size
into the 1.5" dia shaft
Ahmet Erkan/R... I will post a response and copy you with their comments.
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Since I read your last posting, with the very light load you are talking
about the shaft strength would not be a factor, however I thought someone
else may benefit from the information.
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
How does one determine what diameter S/S shaft to use ?
I don't think the engine horse power rating alone would suffice, I would
think both the maximum shaft Horse Power and rpm would need to be known so
that the torque could be calculated. The shock load ought to be predicted
based on the size of the flywheel and if the prop gets jammed abruptly
instead of a line getting wrapped around it causing a smoother stop. Nothing
is easy.
I will see if Ryan can teach me how to figure this out, and I will pass it
on to the list.
Does anyone have a table with standard S/S shaft diameters and corresponding
maximum recommended torque ?
Cheers,
Ahmet
___________________________________________________________________________
|| The Live-Aboard List : send a "subscribe" or "unsubscribe" request ||
|| in body of message to: ||
|