2.a) Davit Calculation

MSET ENGINEERING CORPORATION SDN BHD DOCUMENT TITLE: DESIGN CALCULATION DOC. REF. NO.: MSETe/M2-152 SUBJECT: DAVIT CALC. ISO 9001:2000 REF: 4.0 1.0 MOMENT AND FORCES IN DAVIT AND VESSEL

(Ref:Pressure Vessel Design Manual 3rd Edition by Dennis R. Moss Page 291~295) 1.1 Load on davit Weight of Blind, WL Weight of Davit (Boom + Brace), W1 Axial Load, P = WL + W1

: : =

Vertical Impact Factor, Cv Horizontal Impact Factor, Ch

: :

Vertical Force, fv = Cv x P Horizontal Force, fh = Ch x P

= =

1.2 Bending Moment in Davit Mast, M1 Length of Boom, L1 Length of Mast, L2 Length L5

= = =

Moment, M1 = fvL1 + 0.5W1L1 + fhL2

=

Figure 1: Davit

1542.08 Kg 44.6 Kg 1586.7 kg 1.5 0.5 23348.39095 N 7782.796984 N

997 mm 889 mm 462 mm 30415490.2 Nmm

2.0 STRESS IN DAVIT

2.1 Mast Properties Mast Material Yield Stress, Fy Allowable Axial Stress, Fa = 0.6Fy Allowable Bending Stress, Fb = 0.66Fy Outside Diameter, Do Outside Radius, a Wall Thickness of Davit, tp Inside Diameter, Di Cross Sectional Area, A1 = π/4 x(Do2-Di2) Section Modulus, Z1 = (π/32Do)x (Do4-Di4) Moment Inertia, I = π/64 x(Do4-Di4) Radius of Gyration, r = Sqrt(I/A) Axial Stress at Mast, fa = P/A Bending Stress at Mast, fb = M1/Z1 Combined Stress, fa/Fa + fb/Fb Calculate Combined Stress Since Calculate Combined Stress