We have several air cooler systems where we had to qualify the nozzle loads for OPE+WIND at a hurricane zone category 3. Since the loads were too high, and we couldn't meet the allowable loads, the vendor agreed to use weight+wind only because they will shut down the systems (no temperature). The project plans that all the systems will be shut down 5 hours before the hurricane hits the facility.

Which case should I use to report weight + wind to the vendor?

1. Cases 19 to 21 (segregated of wind)
2. Cases 29 to 32 (segregated of wind + weight)
3. Create a new load case using W+P1+WIND1,2,3 and 4.

What would be the difference among these 3 options?

These are the load cases used in my project.
1 (HGR) CASE NOT ACTIVE
2 (HGR) CASE NOT ACTIVE
3 (HYD) WNC+HP+H
4 (SUS) WNC+H
5 (OPE) W+T1+P1+H+F1
6 (OPE) W+T2+P1+H+F1
7 (OPE) W+T3+P1+H+F1
8 (OPE) W+T1+P1+H+F1+WIN1
9 (OPE) W+T1+P1+H+F1+WIN2
10 (OPE) W+T1+P1+H+F1+WIN3
11 (OPE) W+T1+P1+H+F1+WIN4
12 (OPE) W+T1+P1+H+U1+F1
13 (OPE) W+T1+P1+H+U2+F1
14 (OPE) W+T1+P1+H+U3+F1
15 (OPE) W+T1+P1+H-U1+F1
16 (OPE) W+T1+P1+H-U2+F1
17 (OPE) W+T1+P1+H-U3+F1
18 (SUS) W+P1+H+F1
19 (OCC) L19=L8-L5
20 (OCC) L20=L9-L5
21 (OCC) L21=L10-L5
22 (OCC) L22=L11-L5
23 (OCC) L23=L12-L5
24 (OCC) L24=L13-L5
25 (OCC) L25=L14-L5
26 (OCC) L26=L15-L5
27 (OCC) L27=L16-L5
28 (OCC) L28=L17-L5
29 (OCC) L29=L19+L18
30 (OCC) L30=L20+L18
31 (OCC) L31=L21+L18
32 (OCC) L32=L22+L18
33 (OCC) L33=L23+L18
34 (OCC) L34=L24+L18
35 (OCC) L35=L25+L18
36 (OCC) L36=L26+L18
37 (OCC) L37=L27+L18
38 (OCC) L38=L28+L18
39 (EXP) L39=L5-L18
40 (EXP) L40=L6-L18
41 (EXP) L41=L7-L18
42 (EXP) L42=L6-L7

Best regards,

Use option 3. In fact W+WIND1,2,3 and 4.

Difference is in case that you have non-linear system. Load case 8...11 is no longer valid since the system is cold when the hurricane hit the Plant.

Dear suckreman,

T1 temperature is design or operating temperature for your system.
If T1 is design temp. Means, need not to check wind and seismic at a design T1 condition.
you have to check the wind and seismic at operating T2 or T3 condition. This can happen during the plant operating condition. So T1 check is not required for wind and seismic.

By

Rajiv

Dear suckreman,

T1 temperature is design or operating temperature for your system.
If T1 is design temp. Means, need not to check wind and seismic at a design T1 condition.
you have to check the wind and seismic at operating T2 or T3 condition. This can happen during the plant operating condition. So T1 check is not required for wind and seismic.

By

Rajiv

T1 is Operating Temperature, T2 is Design Maximum and T3 Design Minimum.

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