Gasket Baut Perhitungan moment

NPS = 2 in E = 3,0625in D baut = 0,625 in A = 6 in K = 2,38 D lubang baut = 0,75 in T = 0,75 in L = 2,5 in Jumlah lubang baut = 2 R = 3,625 in B = 2,07 9.5. Flange dan Bolting 9.5.1. Flange Bahan : High Alloy Steel SA 240 Grade O Type 405 Tensile : 60.000 psi All.Stress : 15.000 psi Tipe : ring flange

9.5.2. Gasket

- Bahan : asbestos - m : 2 - minimum design stress : 1600 psi - Tebal gasket 1 pm y p.m y di do + − − = Dimana : y = yield stress = 1600 m = gasket faktor = 2 do = diameter luar gasket di = diameter dalam gasket = diameter luar shell = 168 in P = internal pressure = 1 atm = 14,7 lbin 2 1 14,72 1600 14,7x2 1600 di do + − − = = 1,0047 do = 1,0047 x di = 1,0047 x 180 = 180,846 in Lebar gasket minimum A = 2 di do − = 2 180 180,846 − = 0,423 in Universitas Sumatera Utara Diameter rata-rata gasket G = di + A = 180 + 0,423 = 180,423 in

9.5.3. Baut

- Bahan : High Alloy Steel SA 193 Grade B 8 type 304 - Tensile : 75.000 psi - All.stress : 15.000 psi - manentukan jumlah dan ukuran baut Beban gasket Wm 2 = H y = π . b . G . y Dimana : b = lebar efektif gasket G = diameter rata-rata gasket y = yield stress b o = A2 = 0,423 2 = 0,2115 in ¼ sehingga b o = b Wm 2 = π . b . G . y = 3,14 x 0,2115 x 180,423 x 1600 = 191713,1496 lb beban agar baut tidak bocor Hp = 2 . b . п . G . m . P = 2x 0,2115x 3,14 x 180,423 x 2 x14,7 = 7045,4582 lb beban karena tekanan dalam H = п4 . G 2 . P = 7 , 14 423 , 180 4 14 . 3 2 x x = 375639,0998 lb total berat kondisi operasi Wm 1 = H + Hp = 375639,0998 + 7045,4582 = 382684,5581 lb Wm 1 Wm 2 maka yang digunakan untuk mengontrol adalah Wm 1 Perhitungan luas minimum bolting area : Universitas Sumatera Utara Am 1 = 2 1 in 25,5123 15000 1 382684,558 fall Wm = = Perhitungan bolt optimum Dari Brownel young, tabel 10.4 hal 188 : Root area = 2,652 in Bolt spacing = 4 14 in R = 2 12 in E = 2 Jumlah baut = 10 9,6 2,652 25,5123 area Root Am 1 ≈ = = - Bolting circle diameter C = Di shell + 21,4159 q o + R = 179 + 21,4159 . 316 + 2 12 = 182,0309 in - Diameter luar flange = C + 2.E = 182,0309 + 2 . 2 = 186,0309 in Cek lebar gasket Ab actual = Jumlah baut x Root area = 10 x 2,652 = 26,52 in 2 Lebar gasket minimum L = Ab actual x G . y . π . 2 f = 26,52 x 180,423 x 1600 x 3,14 x 2 15000 = 0,2194 in L A lebar gasket memenuhi

9.5.4. Perhitungan moment

- Keadaan bolting up tanpa tekanan dalam W = 2 Ab Am actual + x f all = 2 52 , 26 25,5123 + x 15000 = 390242,279 lb Universitas Sumatera Utara - Jarak radial dari beban gasket yang bereaksi terhadap bolt circle h G = ½ C – G = ½ 182,0309 – 180,423 = 0,8093 in - Moment flange M G = h G . W =0,8093 x 390242,279 = 313747,4753 lb in - Dalam kondisi operasi W = Wm 1 = 382684,5581 lb - Gaya hidrostatik pada daerah dalam flange H D = 0,785 x B 2 x P = 0,785 x 180 2 x 14,7 = 373879,8 lb Brownell Young, hal 242 - Radial bolt circle h D = ½ x C - B = ½ x 182,0309 - 180 = 1,0155 in - Momen komponen M D = H D x h D = 373879,8 x 1,0155 = 379667,9267 lb in - Perbedaan antara beban baut flange dengan gaya hidrostatik dalam area flange H G = W – H = 390242,279 – 375639,0998 = 14603,17922 lb M G = H G x h G = 14603,17922 x 0,8093 =11740,6822 lb in - Perbedaan antara gaya hidrostatik total dengan gaya hidrostatik dalam acara flange H T = H - H D = 375639,0998– 373879,8 = 1759,2998 lb Universitas Sumatera Utara h T = ½ x h D + h G = ½ x 1,0155 + 0,8093 = 0,9097 in - Momen komponen M T M T = H T x h T = 1759,2998 x 0,9097 = 1600,49 lb in - Momen total pada keadaan operasi M o = M D + M G + M T = 379667,9267 + 11740,6822 + 1600,49 = 393009,1 lb in M max = M o = 393009,1 lb in

9.5.5. Perhitungan Tebal Flange