DriveMeNuts
Mechanical
- May 4, 2018
- 447
For flat heads, I am wondering what the definition of "factor of safety" is for UG-34(d)(10).
Does the mechanical locking mechanism need to be calculated of proof tested to fail at 4 times its design loading?
Or does the margin on yield for the mechanical locking mechanism need to be changed from 1.5 to 4.0?
Or does the margin on UTS for the mechanical locking mechanism need to be changed from 3.5 to 4.0?
The code Clause is:
UG-34(d)(10) Sketches (m),
, and (o). C = 0.3 for a circular plate inserted into the end of a vessel and held in place by a positive mechanical locking arrangement, and when all possible means of failure (either by shear, tension, compression, or radial deformation, including flaring, resulting from pressure and differential thermal expansion) are resisted with a factor of safety of at least four. Seal welding may be used, if desired.
Does the mechanical locking mechanism need to be calculated of proof tested to fail at 4 times its design loading?
Or does the margin on yield for the mechanical locking mechanism need to be changed from 1.5 to 4.0?
Or does the margin on UTS for the mechanical locking mechanism need to be changed from 3.5 to 4.0?
The code Clause is:
UG-34(d)(10) Sketches (m),
, and (o). C = 0.3 for a circular plate inserted into the end of a vessel and held in place by a positive mechanical locking arrangement, and when all possible means of failure (either by shear, tension, compression, or radial deformation, including flaring, resulting from pressure and differential thermal expansion) are resisted with a factor of safety of at least four. Seal welding may be used, if desired.