Dear all,
i am doing a calculation for a vertical vessel, in which my hydrotest pressure is based on "UG 99C" in the horizontal position.
when i calculate it in PVElite 2008, i m not getting that how the values are come. I have considered 90% of yield stress for hydro.
can anyone please tell me from where these values are came (Highlighted)?

Cylindrical Shell From 40 To 50 SA-516 70 , UCS-66 Crv. B at 100C

Thickness Due to Internal Pressure [Tr]:
= (P*R)/(S*E-0.6*P) per UG-27 (c)(1)
= (4.171*1503.0000)/(1407.20*0.85-0.6*4.171)
= 5.2557 + 3.0000 = 8.2557 mm

Max. Allowable Working Pressure at given Thickness, corroded [MAWP]:
Less Operating Hydrostatic Head Pressure of 0.651 kgf/cm²
= (S*E*t)/(R+0.6*t) per UG-27 (c)(1)
= (1407.20*0.85*9.0000)/(1503.0000+0.6*9.0000)
= 7.131 - 0.651 = 6.481 kgf/cm²

Maximum Allowable Pressure, New and Cold [MAPNC]:
= (S*E*t)/(R+0.6*t) per UG-27 (c)(1)
= (1407.20*0.85*12.0000)/(1500.0000+0.6*12.0000)
= 9.516 kgf/cm²

Actual stress at given pressure and thickness, corroded [Sact]:
= (P*(R+0.6*t))/(E*t)
= (4.171*(1503.0000+0.6*9.0000))/(0.85*9.0000)
= 822.990 kgf/cm²

Hydrostatic Test Pressure Results:
Pressure per UG99b = 1.3 * M.A.W.P. * Sa/S = 8.425 kgf/cm²
Pressure per UG99b[34] = 1.3 * Design Pres * Sa/S = 4.576 kgf/cm²
Pressure per UG99c = 1.3 * M.A.P. - Head(Hyd)= 11.939 kgf/cm²
From this above (UG99c)formula the static head becomes 0.4318 Kg/cm2.
Pressure per UG100 = 1.1 * M.A.W.P. * Sa/S = 7.129 kgf/cm²

Horizontal Hydrotest performed in accordance with: UG-99c
Stresses on Elements due to Hydrostatic Test Pressure:

For SHELL:-
Actual stress = 2415.0
Allowable Stress = 2406.3
Ratio = 1.004
Pressure = 12.24
Why this pressure is 12.24 Kg/cm2 ? if this pressure is without head, then it should be 12.3708 Kg/cm2.

The Maximum Allowable test pressure is 11.895 kgf/cm²
From where above value comes?

Now the last question is, the ratio is 1.004. is that acceptable? because program not giving any error message for this excepting red colour.

please reply soon, i will highly appreciate.

Dear All,
can anyone reply on this please?

There is a bit of mix-up. The operating static head (not the hydro test static head) is nominated 0.651 kgf/cm2. The vessel ID is 3006 mm, hence the hydro test water static head on the bottom of the vessel is 0.301 kgf/cm2. If you deduct this pressure from the actual hydro test pressure, you get the test pressure of the top of the shell in horizontal position.
I suggest to read carefully the UG-99(c) and you calculate by hand the test pressure as required by the Code. One thing, the PV Elite is correct in calculating the correct test pressures, but you also need to interpret the Code wording. The minimum test pressure is calculated at the top of the shell in horizontal position. In the same time, on the bottom of the shell the test pressure is higher, by adding the static head of the water, equal to the vessel ID. That means the bottom of the shell is overstressed by a margin given by the test static head. In your case, the calculated ratio of the test pressure at the top and the test pressure at the bottom is 1.00365 (or as rounded up by the program is 1.004). Obviously, this ratio is acceptable to the Code, provided that you ensure the excess pressure at the bottom will not generate stress in excess of 90% of the yield. The red mark is only there to make you aware that the normal test pressure is exceeded in the bottom and is now subject to your engineering skills to accept it or ask your Client if it is acceptable.
Cheers,
gr2vessels

gr2vessels,
I do not think vessel ID is 3006mm. If you look at the MAP formula, radius value is given surely in uncorroded condition and it is 1500mm.

The MAWP for the new and uncorroded condition is irrelevant to the Client / vessel operator. Hence the uncorroded radius of 1500 mm is also irrelevant. The only relevant data is the MAWP in the fully corroded condition (for which the ID is 3006 mm).
Best regards,
gr2vessels

Vessel thickness value is chosen as 12mm.
If you look at UG-27(c)formula above, you can see the value 1503. and it comes from Ri+CA = 1500 + 3 =1503mm

So vessel inside radius is 1500mm.

So what is the point of the new vessel inside radius being 1500 mm. It is indeed 1500 mm. Please explain what is the relevance of your persistent note of 1500 mm inside radius and how it is related to the Mak's question?

Mak,
Please provide us your medium's density value?

And you wrote that
"Cylindrical Shell From 40 To 50"
so it means that it is not the bottom cylinder which attached to head.
Static head value will be changed.