Full resolution (JPEG) - On this page / på denna sida - Strength of Materials - To find the diameter of a bolt to resist a given load - To find the thickness of a cylinder to resist a given pressure
<< prev. page << föreg. sida << >> nästa sida >> next page >>
Below is the raw OCR text
from the above scanned image.
Do you see an error? Proofread the page now!
Här nedan syns maskintolkade texten från faksimilbilden ovan.
Ser du något fel? Korrekturläs sidan nu!
This page has never been proofread. / Denna sida har aldrig korrekturlästs.
STRENGTH OF MATERIALS. 219
Example 2.
What size of bolt is required to sustain the same load as is
mentioned in the previous example, if only 5 is wanted as a
factor of safety?
Solution
:
* = ^4450 X 5
50000 X 0.7854
D = Vo.567
J) = 0.75 inch diameter in bottom of thread.
Thus a ^-inch standard screw is too small, as that is only
ff" in bottom of thread, but a 1-inch standard screw is suffi-
cient, being f f" in bottom of thread.
To Find the Thickness of a Cylinder to Resist a Given
Pressure.
When the walls of cylinders are thin in proportion to their
diameters use the formula
:
p — S X t
R x/
f= P XPXf
P =
S
S X /
P x/
p = Pressure per square inch.
P = Radius of cylinder in inches.
/ = Thickness of cylinder wall in inches.
f= Factor of safety.
S = Ultimate tensile strength of material.
When cylinder walls are thick in proportion to the diameter,
such as hydraulic cylinders, their thickness is usually figured
by the formula:
P X P
t = Thickness of cylinder wall in inches.
P = Pressure in pounds per square inch.
P = Radius of cylinder.
S = Ultimate tensile strength.
f= Factor of safety.
Example.
Find necessary thickness of a hydraulic cylinder of 10-inch
inside diameter, made from cast-iron, to stand a pressure of 1000
<< prev. page << föreg. sida << >> nästa sida >> next page >>
