Client Document Number
Makers Nr.
Eqpt. Prepared by Checked by
Name Name
Calculation Title STIFFNER CALCULATIONS
Sign Sign
Rev. by Approved by
Rev. Revision Details
Name Sign Name Sign
For Unfired Boilers pressure = 500 mmwc Restrict spacing between two stiffners - 700 & 750mm
For Fired Boilers pressure = 300 mmwc If Beyond 750mm - Horizontal Stiffners to be provided
length horizontal thicknes Required
Allowble uniform Maximum
W.P Temp of pitch of s of skin section ISMC Zx
sl.nr Description material stress distribution Bending
(kg/m2) (0c) stiffner stiffner plate modulus (cm3)
(N/mm2) load on moment
(m) (m) (m) cm3
stiffner (t/m) (wl2)/8 KNM < ISMC
Evaporator Hopper SA 240
1 plate-1 500 700 TP304 27.13 3.91 0.5 0.006 0.25 4.78 176.10 ISMC 200 181.9
Evaporator Hopper SA 240
2 plate-2 500 700 TP304 27.13 2.86 0.5 0.006 0.25 2.56 94.22 ISMC 150 103.9
Economiser-1 Hopper
3 plate-1 500 400 IS 2062 90.78 5.3 0.5 0.006 0.25 8.78 96.70 ISMC 150 103.9
Economiser-1 Hopper
4 plate-2 500 400 IS 2062 90.78 3.088 0.5 0.006 0.25 2.98 32.83 ISMC 100 37.3
Economiser-2 Hopper
5 plate-1 500 300 IS 2062 106.86 5.3 0.5 0.006 0.25 8.78 82.15 ISMC 150 103.9
Economiser-2 Hopper
6 plate-2 500 300 IS 2062 106.86 3.088 0.5 0.006 0.25 2.98 27.89 ISMC 100 37.3
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kg/m cm cm2 cm cm cm
section weight section ht c/s area CGx base CGx tip CGy base
1 0 0 0 0 0 0 0
2 ISA 30x30x3 1.4 3 2.03 0.83 2.17 0.83
3 ISA 30x30x4 1.8 3 2.26 0.87 2.13 0.87
4 ISA 30x30x5 2.2 3 2.77 0.92 2.08 0.92
5 ISA 40x40x3 1.8 4 2.34 1.08 2.92 1.08
6 ISA 40x40x4 2.4 4 3.07 1.12 2.88 1.12
7 ISA 40x40x5 3 4 3.78 1.16 2.84 1.16
8 ISA 40x40x6 3.5 4 4.47 1.2 2.8 1.2
9 ISA 45x45x3 2.1 4.5 2.64 1.2 3.3 1.2
10 ISA 45x45x4 2.7 4.5 3.47 1.25 3.25 1.25
11 ISA 45x45x5 3.4 4.5 4.28 1.29 3.21 1.29
12 ISA 45x45x6 4 4.5 5.07 1.33 3.17 1.33
13 ISA 50x50x3 2.3 5 2.95 1.32 3.68 1.32
14 ISA 50x50x4 3 5 3.88 1.37 3.63 1.37
15 ISA 50x50x5 3.8 5 4.79 1.41 3.59 1.41
16 ISA 50x50x6 4.5 5 5.68 1.45 3.55 1.45
17 ISA 65x65x5 4.9 6.5 6.25 1.77 4.73 1.77
18 ISA 65x65x6 5.8 6.5 7.44 1.81 4.69 1.81
19 ISA 65x65x8 7.7 6.5 9.76 1.89 4.61 1.89
20 ISA 65x65x10 9.4 6.5 12 1.97 4.53 1.97
21 ISA 75x75x5 5.7 7.5 7.27 2.02 5.48 2.02
22 ISA 75x75x6 6.8 7.5 8.66 2.06 5.44 2.06
23 ISA 75x75x8 8.9 7.5 11.4 2.14 5.36 2.14
24 ISA 75x75x10 11 7.5 14 2.22 5.28 2.22
25 ISA 100x100x6 9.2 10 11.7 2.67 7.33 2.67
26 ISA 100x100x8 12.1 10 15.4 2.76 7.24 2.76
27 ISA 100x100x10 14.9 10 19 2.84 7.16 2.84
28 ISA 100x100x12 17.7 10 22.6 2.92 7.08 2.92
29 ISMC 75 7.14 7.5 9.1 3.75 3.75 1.32
30 ISMC 100 9.56 10 12.2 5 5 1.54
31 ISMC 125 13.1 12.5 16.7 6.25 6.25 1.95
32 ISMC 150 16.8 15 21.3 7.5 7.5 2.2
33 ISMC 175 19.6 17.5 24.9 8.75 8.75 2.19
34 ISMC 200 22.3 20 28.5 10 10 2.2
35 ISMC 225 26.1 22.5 33.3 11.25 11.25 2.31
36 ISMC 250 30.6 25 30.6 12.5 12.5 2.3
37 ISMC 300 36.3 30 46.3 15 15 2.35
38 ISMC 350 42.7 35 54.4 17.5 17.5 2.44
39 ISMC 400 50.1 40 63.8 20 20 2.42
40 ISMB 100 8.9 10 11.4 5 5 2.5
41 ISMB 125 13.3 12.5 17 6.25 6.25 3.5
42 ISMB 150 15 15 19.1 7.5 7.5 3.75
43 ISMB 175 19.6 17.5 25 8.75 8.75 4.25
44 ISMB 200 24.2 20 30.8 10 10 5
45 ISMB 225 31.1 22.5 39.7 11.25 11.25 5.5
46 ISMB 250 37.3 25 47.5 12.5 12.5 6.25
47 ISMB 300 46.6 30 58.6 15 15 7
48 ISMB 350 52.2 35 66.7 17.5 17.5 7
49 ISMB 400 61.5 40 78.4 20 20 7
50 ISMB 450 72.4 45 92.2 22.5 22.5 7.5
51 ISMB 500 86.9 50 111 25 25 9
52 ISMB 550 104 55 132 55 55 9.5
53 ISMB 600 123 60 156 60 60 10.5
S.no Section Zxx in cm3 Wt. In Kg/m3
1 ISA 45x45x3 1.5 2.1
2 ISA 45x45x4 2 2.7
3 ISA 45x45x5 2.5 3.4
4 ISA 45x45x6 2.9 4
5 ISA 50x50x3 1.9 2.3
6 ISA 50x50x4 2.5 3
7 ISA 50x50x5 3.1 3.8
8 ISA 50x50x6 3.6 4.5
9 ISA 65x65x5 5.2. 4.9
10 ISA 65x65x6 6.2 5.8
11 ISA 65x65x8 8.1 7.7
12 ISA 65x65x10 9.9 9.4
13 ISA 75x75x5 7.1 5.7
14 ISA 75x75x6 8.4 6.8
15 ISA 75x75x8 11 8.9
16 ISA 75x75x10 13.5 11
17 ISA 90x90x6 12.2 8.2
18 ISA 90x90x8 16 10.8
19 ISA 90x90x10 19.8 13.4
20 ISA 90x90x12 23.3 15.8
21 ISA 100x100x6 15.2 9.2
22 ISA 100x100x8 20 12.1
23 ISA 100x100x10 24.7 14.9
24 ISA 100x100x12 29.2 17.7
25 ISA 110x110x8 24.4 13.4
26 ISA 110x110x10 30.1 16.5
27 ISA 110x110x12 35.7 19.6
28 ISA 110x110x15 43.7 24.2
29 ISA 130x130x8 34.5 15.9
30 ISA 130x130x10 42.7 19.7
31 ISA 130x130x12 50.7 23.4
32 ISA 130x130x15 62.3 28.9
33 ISMC 75 20.3 7.14
34 ISMC 100 37.3 9.56
35 ISMC 125 66.6 13.1
36 ISMC 150 103.9 16.8
37 ISMC 175 139.8 19.6
38 ISMC 200 181.9 22.3
39 ISMC 225 239.5 26.1
40 ISMC 250 305.3 30.6
41 ISMC 300 424.2 36.3
42 ISMC 350 571.9 42.7
43 ISMC 400 754.1 50.1
44 ISMB 100 51.5 8.9
45 ISMB 125 71.8 13.3
46 ISMB 150 96.9 15
47 ISMB 175 145.4 19.6
48 ISMB 200 223.5 24.2
49 ISMB 225 305.9 31.1
50 ISMB 250 410.5 37.3
51 ISMB 300 573.6 46.6
52 ISMB 350 778.9 52.2
53 ISMB 400 1022.9 61.5
54 ISMB 450 1350.7 72.4
55 ISMB 500 1808.7 86.9
56 ISMB 550 2359.8 104
57 ISMB 600 3060.4 123
cm cm4 cm4 Zxx,cm3
Cgy tip Ixx Iyy t in cm
0 0 0 0
2.17 1.4 1.4 0.3
2.13 1.8 1.8 0.4
2.08 2.1 2.1 0.5
2.92 3.4 3.4 0.3
2.88 4.5 4.5 0.4
2.84 5.4 5.4 0.5
2.8 6.3 6.3 0.6
3.3 5 5 0.3 1.5 ISA 45x45x3
3.25 6.5 6.5 0.4 2 ISA 45x45x4
3.21 7.9 7.9 0.5 2.5 ISA 45x45x5
3.17 9.2 9.2 0.6 2.9 ISA 45x45x6
3.68 6.9 6.9 0.3 1.9 ISA 50x50x3
3.63 9.1 9.1 0.4 2.5 ISA 50x50x4
3.59 11 11 0.5 3.1 ISA 50x50x5
3.55 12.9 12.9 0.6 3.6 ISA 50x50x6
4.73 24.7 24.7 0.5 5.2. ISA 65x65x5
4.69 29.1 29.1 0.6 6.2 ISA 65x65x6
4.61 37.4 37.4 0.8 8.1 ISA 65x65x8
4.53 45 45 1 9.9 ISA 65x65x10
5.48 38.7 38.7 0.5 7.1 ISA 75x75x5
5.44 45.7 45.7 0.6 8.4 ISA 75x75x6
5.36 59 59 0.8 11 ISA 75x75x8
5.28 71.4 71.4 1 13.5 ISA 75x75x10
7.33 111 111 0.8 15.2 ISA 100x100x6
7.24 145 145 1 20 ISA 100x100x8
7.16 177 177 1 24.7 ISA 100x100x10
7.08 207 207 1.2 29.2 ISA 100x100x12
2.68 78.5 12.9 20.3 ISMC 75
3.45 192 26.7 37.3 ISMC 100
4.55 425 61.1 66.6 ISMC 125
5.3 788 103 103.9 ISMC 150
5.31 1240 122 139.8 ISMC 175
5.3 1830 141 181.9 ISMC 200
5.69 2710 188 239.5 ISMC 225
5.7 3880 211 305.3 ISMC 250
6.65 6420 313 424.2 ISMC 300
7.56 10000 434 571.9 ISMC 350
7.58 15200 508 754.1 ISMC 400
2.5 183 12.9 51.5 ISMB 100
3.5 445 38.5 71.8 ISMB 125
3.75 718 46.8 96.9 ISMB 150
4.25 1260 76.7 145.4 ISMB 175
5 2120 137 223.5 ISMB 200
5.5 3440 218 305.9 ISMB 225
6.25 5130 335 410.5 ISMB 250
7 8990 486 573.6 ISMB 300
7 13600 538 778.9 ISMB 350
7 20500 622 1022.9 ISMB 400
7.5 30400 834 1350.7 ISMB 450
9 45200 1370 1808.7 ISMB 500
9.5 64900 1830 2359.8 ISMB 550
10.5 91800 2650 3060.4 ISMB 600
DESIGN PLATE STIFFNER
Tem Allowble length of horizontel
W.P
sl.nr Description p material stress stiffner pitch of
(kg/m2)
(0c) (N/mm2) (m) stiffner (m)
SA 240 - 304
1 1400 450 TYPE 77.4 2.5 0.5
Maximum Required
Bending section
uniform distribution load on moment (wl2)/8 modulus ISMC Zx
stiffner (t/m) KNM cm3 < ISMC (cm3)
0.7 5.47 70.66 < ISMC 150 105
DESIGN PLATE STIFFNER
thickness of
skin plate (m)
0.006
Remarks
Client Document Number
Makers Nr.
Eqpt. Prepared by Checked by
Name Name
Calculation Title STIFFNER CALCULATIONS
Sign Sign
Rev. by Approved by
Rev. Revision Details
Name Sign Name Sign
For Unfired Boilers pressure = 500 mmwc Restrict spacing between two stiffners - 700 & 750mm
For Fired Boilers pressure = 300 mmwc If Beyond 750mm - Horizontal Stiffners to be provided
length
horizontal thicknes Required
Allowble of uniform Maximum
W.P Temp pitch of s of skin section Plate Zx
sl.nr Description material stress stiffner distribution Bending
(kg/m2) (0c) stiffner plate modulus (cm3)
(N/mm2) plate load on moment
(m) (m) cm3
(m) stiffner (t/m) (wl2)/8 KNM Plate
Evaporator Hopper 10 150
1 plate-1 500 700 IS 2062 139.11 3.91 1 0.006 0.5 9.56 68.69 37.5
Evaporator Hopper 10 150
2 plate-2 500 700 IS 2062 27.13 2.86 0.5 0.006 0.25 2.56 94.22 0
10 150
3 0.006 0 0.00 #DIV/0! 0
10 150
4 0.006 0 0.00 #DIV/0! 0
10 150
5 0.006 0 0.00 #DIV/0! 0
10 150
6 0.006 0 0.00 #DIV/0! 0
10 150
7 0.006 0 0.00 #DIV/0! 0
10 150
8 0.006 0 0.00 #DIV/0! 0
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