44. What do you need to prepare and

44. What do you need to prepare and and then to input into CAESAR II or Autopipe for Stress Analysis?
- .i) Pipe Size ii) Fluid Temperature iii) Pipe Material iv)Design pressure v)Insulation Thickness vi)Specific gravity vii)Friction coeff. viii) Model
- Code used, design pressure, design/operating temperature, test pressure, material properties (size, material type, sch./w.t, CA, SY/SC/SH, poisson ratio, pipe density), fluid density, insulation data (type & density), support location, equipment data, environment data.
- We need to prepare stress sketch and all the pipe properties, such as Line Size, Line Material, Line Class, Ope and Des Temp
45. What type of loads available in the stresss analysis calculation? Please Explain.
- sustain load : inside pressure, pipe (incl. valves, flanges, etc.) weight thermal load : ambient, design & operating temperatures
46. Do you know about Load Cases in Stress Analysis? Please Explain.
- normal are sustain, operating & expansion load. additional are environtment load & mechanical load.
47. What is Load Case for Sustained Load, Expansion Load, Stress Range, Occasional Load, Spring?
- sustain : weight (specific gravity/density) + inside pressure expansion : delta temperature stress range : — i don’t know — occasional : wind, earthquake/seismic, external force, slug/hammer, reaction froce of PSV
48. What is the failure theory under ASME B31.3?
- SL (sustain) >< SY
- SL (sustain) >< Sy
49. Do you know what type of piping failure during its operation?
50. What is the desired life cycle for piping during operation?
- based on ASME B31.3, around 7000 cycles
- 7000cycle?
51. How to calculate thermal expansion in a pipe?
- delta L = exp. coeff. x delta T x L
- By multiplying coefficient of thermal exp to its length
52. Do you know SIF (Stress Intensification Factor)? Explain and give some examples?
- stress max value occuring because of material repositioning. ex. : tee, ellbow
- SIF is a factor to calculate what is the real stress that will be applied to the component due to difference of the component geometric..for example, straight pipe will have SIF 1, if this pipe connected to elbow, the on the elbow the stress will be higher than the pipe even thought the condition is the same, because the elbow SIF is higher (but I don’t know the value
53. Pipe Support. What is the pipe support span?
- distance between two pipe supporting point.
- (Max distance of the support to ensure that the deflection due to dead load is limited by a half inch.)
54. What is the criteria to determine the span of pipe support?
- depend on size + wall thk. & fluid density
- Half inch of the deflection due to dead load)
55. How do we decide an anchor point at Expansion Loop on pipe rack?
- near to end of pipe rack.
- depend on the temperature of the line, higher temp line required shorter distance of the anchor point
56. What is the steam out condition?
- Condition when we purging the line for cleaning?
57. On Heat Exchanger, where do you provide an anchor support and slotted support? and Why?
- support near to inlet & outlet nozzle should be slotted support. then another one is anchor/fixed support.
- Anchor point shall be given on the tube bundle side, that is for maintenance reason, when we pull the tube, we want the equipment remaining fix (not moving))
58. Do you know PTFE on Support? Why we need that?
- when we don’t want over-force (vertical and/or horizontal) acting at pipe support.
- when we don’t want over-force (vertical and/or horizontal) acting at pipe support.
- PTFE or telfon is used to reduce the friction of the support. Then it will affect the nozzle load or any load on the stopper)
59. Tell me about spring support.Why we need it? And how many type of spring support? Explain as much as you can.
- Spring support is needed to absorb over load (force) or over displacement occured becuse of restrained-pipe. type of spring : variable & constant variable is used when there is sufficient distance around pipe, so that the spring support can travel thoroughly. this is used for absorp over-force reacted at rigid-type support. constant is used when there is only small dimension of distance. this is used as variable plus stabilize center position of pipe in the system.
- We need the spring support when during operation, the pipe is in lifting condition, which mean it is not supported properly(if we used normal shoe or others). So, with the spring support, when the pipe is lifting, the spring support will also lifted and make sure that the pipe is supported. But we have to check first if we need the spring support or not. When we remove the lifting support and the sustain case still pass the code, this mean that we don’t need the spring support. Just put normal support and let the pipe lifting. There are 2 type of spring support. Variable Spring support and Constant Spring support)