Dear Experts,

I would like to ask for the suggestion about my calculation of riser lines to pig launchers and receivers in offshore platform.

I applied wave loads in to my calculation in X,-X,Z and -Z directions and load cases are following;

CASE 1 (HYD) WW+HP
CASE 2 (OPE) W+T1+P1
CASE 3 (OPE) W+T1+P1+WAV1
CASE 4 (OPE) W+T1+P1+WAV2
CASE 5 (OPE) W+T1+P1+WAV3
CASE 6 (OPE) W+T1+P1+WAV4
CASE 7 (SUS) W+P1
CASE 8 (EXP) L8=L2-L7
CASE 9 (OCC) L9=L3-L2
CASE 10 (OCC) L10=L4-L2
CASE 11 (OCC) L11=L5-L2
CASE 12 (OCC) L12=L6-L2
CASE 13 (OCC) L13=L9+L7
CASE 14 (OCC) L14=L10+L7
CASE 15 (OCC) L15=L11+L7
CASE 16 (OCC) L16=L12+L7

I am using Caesar II version 5.20.03 built . Ambient Temp = 84F, Operating Temp = 250F, Operating Press = 1325 lb/sq.in and HYD Press = 2220 lb/sq.in. Design Code are B31.3 and B31.8. Fluid density are 1.95 - 6.75 lb/cu.ft. And supports stiffness at Launchers/Receivers came from structure department.

As checked, I found pipe supports loading in sustained case are heavier than hydtest case. In my opinion that HYD load should be heavier than sustained load????

Please see in the attachment and help. I will appreciate very much.

Very Best Regards,
Billy