I appreciate very much you comments on my questions.-
I have read a lot about this issue but unfortunately there are not a lot of historical records about roughness during shipping & storage in yards and during operation.-
From the forum I detected that you have good experience on this matter...
1.- Ref Brisbane (petroleum ),28 March ; 16:25
Please , confirm that 1000 inches or 0.025 mm (25 microns) ia a good safe design for a gas pipeline of 42" inches and 300 km as you mentioned in the above ref. (without internal coating).
2.- What is a typical roughness of piping when delivered at...