1. Weight calculation of flat edged pipes

W= 0.02466 (D-t) x t, (kg/m)

D= exterior diameter of pipe(mm)

T: pipe wall thickness(mm)

W: Pipe unit weight (kg/m)

2. Hydrostatic Test Pressure

Hydrostatic test pressure is calculated with a calculating

method including a lower tension then flowing rate of steel.

P: hydrostatic Test Pressure (bar)

K: Percentage of flowing rate included to calculation

S: determined minimum flowing tension (MPA)

T: wall thickness of pipe (mm)

D: Exterior diameter of pipe

P= 20 x k x s x t
              D

According to API 5L

GradeA: k=0.60
GradeB: k=0.60
X42 - X80: k= 0.60 < 5 9/16 in
     : k= 0.75 Ext. Dia. 6 5/8-8 5/8 in
     : k= 0.85 Ext. Dia. 10 3/4 -18 in
     : k= 0.90 Ext. Dia. > 20 in

3. Unit surface area

A=D x ş x 10(-3)(m²/m)

A= Unit surface area (m²/m)

D: exterior diameter of pipe (mm)