Design and Construction of CNG Containers (NFPA52 - 4.4)

4.4 Container Capacity. Containers are described by their liquid capacity and their design and allowable service pressures. The liquid capacity [ft³ (m³) of water] is the volume of liquid that is required to fill the container. The gas storage capacity can be calculated from the liquid capacity and allowable service pressure.

Natural Gas Vehicle Codes

A large number of mandatory and voluntary standards cover the varying facets of natural gas vehicle components, conversion, and manufacture, and the fueling stations, repair facilities and garages that service them. Following is a list and short description of the “NGV” series of American National Standards, developed through the Natural Gas Vehicle Coalition with support from the Gas Research Institute, the Canadian Gas Association and CSA International.
These voluntary standards represent natural gas vehicle industry “good practice” for the safety and durability of essential elements in CNG vehicle fueling stations and vehicle fuel systems.

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.

Cover, Clearance, and Casing Requirements for gas pipeline

• Cover Requirements for Mains. Buried mains shall be installed with a cover not less than 24 in. (610.
• Cover Requirements for Pipelines

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