Pipeline Dewatering, Cleaning, and Drying

Newly constructed pipelines are typically hydrostatically tested, using water as the test medium, upon completion of construction.

Once the hydrostatic testing has been completed, it is necessary to remove the water from the line and place the line in service. Dewatering can be a simple process or, if the procedure is not properly planned, a difficult
one.

Determine buoyancy of bare and concrete coated steel pipe in water and mud

Bouyancy of bare & concrete coated

To find the buoyancy in water in lb/ft :

ASME Piping and Vessel Codes

ASME Boiler and Pressure Vessel Code Sections

I. Power Boilers
II. Material Specifications

• Part A – Ferrous Materials
• Part B – Nonferrous Materials
• Part C – Welding Rods, Electrodes, and Filler Metals.

Best Industry Practice: All pressure retaining materials must comply with specifications found in

section 2 part A.

Wall thickness or Design pressure for the gas pipeline

P = Design Pressure, psig

S = Specified Minimum Yiled Strength, psi

t  =  Nominal Wall thickness, inch

D = Nominal Outside diameter, inch

F = Design factor

E = Longitudinal joint factor

T = Temperature derating factor,

Equations Commonly Used for Calculating Gas Pipeline

Pandhandle A