Pipe Lift-Off :
In-Service Piping Lift-Off from their support
Figure 1.
เพจ หมอท่อ Dr.
PipeX
@ 2021
เพจ หมอท่อ Dr.
PipeX
@ 2021
Pipe Lift-Off :
Lift-Off Model
Lift-Off
45
Figure 2. Lift-Off Model. [1]
145
[1] ASME B31.3-2020, Process Piping.
Pipe Lift-Off :
Installation condition by ambient temperature.
เพจ หมอท่อ Dr.
PipeX
@ 2021
Support Load at Node 50 is 26,300 N in the vertically upward direction.
The stress due to sustained loads, SL, at node 50 is 76.3 MPa (11.0 ksi).
Active
Figure 3. Lift-Off Model. [1]
[1] ASME B31.3-2020, Process Piping.
Pipe Lift-Off :
Operating condition at temperature of 288°C.
เพจ หมอท่อ Dr.
PipeX
@ 2021
Node 50 is Lift-Off, Support Load at Node 50 is 0 N.
The stress due to sustained loads, SL, at node 50 is 128.0 MPa (18.6 ksi).
Lift-Off
Inactive
Figure 4. Lift-Off Model. [1]
[1] ASME B31.3-2020, Process Piping.
เพจ หมอท่อ Dr.
PipeX
@ 2021
Stress due to sustained loads, SL = 128.0 MPa Exceed Allowable Stress, Sh = 127 MPa.
Pipe Lift-Off :
Result and Affect
The system is Failed, indicate that the piping system is not protected against
collapse for the cycles under analysis when considering the operating case
support scenario
Figure 5. Table S302.6.3 Sustained Forces, Moments, and Stresses for Sustained Operating Condition With Node 50’s Y+ Support.
Inactive (Lift-Off) [Allowable Stress, Sh = 127 MPa (18.4 ksi) : Fails][1]
The greatest Stresses due to sustained loads, SL, are at elbow nodes 40 and 140
and “Lift-Off” support location, node 50. Therefore, redesign of the piping
system is required.
[1] ASME B31.3-2020, Process Piping.