 |
|||
|
|
|||
| ||||||||||
|
|  MIL-D-18641F(SH)
c.
Maximum value of service stress at periphery of the bolt cross-section resulting from
tension plus bending neglecting stress concentration factor shall be limited to the yield
strength of the material at the design temperature.
d. Threaded fasteners with torque requirements shall be lubricated with red-lead-graphite
mineral oil per MIL-L-24479.
e. The range of inefficient of friction for the lubricant shall be accounted for in
determining torque value as follows:
(1)
Using the hydrostatic test load or the load bawl on design pressure plus
maximum piping load on nozzles, whichever is greater, and high coefficient of
= 0.13), determine torque using the following equation:
friction
Using the installation torque above and low coefficient of friction
= 0.065),
(2)
determine stress from the following equation:
P in this equation is the preload force in pounds, using the low coefficient of
friction (0.065) and the installation torque calculated above. This calculated
stress when combined with other stresses specified in ASME shall not exceed the limits of ASME
Boiler and Pressure Vessel Code, section III.
f. Fatigue analysis of bolts shall be in accordance with section III, division 1, subsection
NB, class 1 of ASME Boiler and Pressure Vessel Code, except that cumulative usage
factor shall not exceed 0.8.
32
|
|
Privacy Statement - Press Release - Copyright Information. - Contact Us |
Click
here for thousands of PDF manuals