Existing Piping Revamping - New operation Conditions - Verification

[Hansito]

Dear colleagues,
We are evaluating a new revamping project with several cases of temperature and pressure increasing. Thinking about the impact I've thinking about some steps to confirm the possibility. Please if you have a different opinion or something to add let me know.

Regards,
Hansito
1) Verify that the new temperature is inside the allowable temperature for the material according to the applicable code.

2) Verify the existing flanges for the new conditions.

3) Verify the existing pipe thickness for the new condition according to the applicable code.
Verify also the thickness for the proper test required.
Some present thickness evaluation is recommended.

4) Verify the stress calculations for the new conditions, including all the boundaries: loads from piping to connected nozzles and structures.
If the line has springs, sizing and calibration must me checked.

 

[Bonswa]

Not sure what type of facility this is, but you may want to include a materials engineer that's familiar with damage mechanisms (API-RP-571).

While verifying that the temperature increases are still within the design conditions, you need to also take into account the product going through it and how the materials will be affected by that product being at a higher temperature. Sulfur is a good example.

Also, with the flanges, verify the the limits of the gaskets being used.

PSV, PSV, PSV

You've got it all together. I'm sure you're operating conditions are not going to raise to the point that you need to worry about what i've listed.

Good luck.

 

[SeanB]

You also have to pull out the original hydrotest records. If your new operating pressure x 1.5 (or is it 1.33 now?)is less than the hydrotest pressure then you are ok. If now, you are looking at having to re-hydrotest the pipe.

 

[JohnBreen]

Identify the most limiting component(s) in the system for pressure/temperature. Evaluate components by applying current Codes. Replace (upgrade) where necessary.

Determine the most likely deterioration mechanisms (corrosion, fatigue.....). Use the API 579-1 / ASME FFS-1 methodology to evaluate the fittness for continued service of the system. Some NDE will be required - especially to determine the remaining wall thickness of the pressure boundaries. Some life fraction analysis should be done.

Do a complete walk-down of the system and look for damage to components (leaks, leaking flange pairs, etc.) and especially to pipe supports and guides (a science in itself). Try to find the system operating history. Off-design operations and upsets should be evaluated. Replace the pressure relief devices with appropriate new devices.

Do complete pipe stress analysis with the new operating conditions. Assess the need for new spring hangers/supports to accommodate the new conditions.