Abstract: A CNG transportation vehicle comprising at least one vernally oriented, generally cylindrical, pressure vessel (10) of the type for containing and transporting CNG, the vessel having a generally cylindrical body and two ends and an opening in the form of a manhole at the top end thereof.

Abstract: A pressure vessel for storage and transportation of CNG comprises a body, which defines an internal volume in which the CNG is stored and transported. An inlet is provided through which the CNG can be loaded into the internal volume of the vessel. At the end of said inlet there is a CNG expansion section through which the CNG expands into the vessel when loaded. The pressure vessel further comprises a CNG loading appendage for injecting the CNG at a point inside the internal volume of the vessel, thereby increasing the space between the expansion point of the CNG and the walls of the vessel.

Abstract: The present invention relates to a method of rotational moulding where a heating structure is incorporated into the mould. Further aspects of the invention relate to a mould for rotational moulding comprising a heating element. In an embodiment, the mould is a pressure vessel for transporting and storing compressed natural gas. The heating element may be incorporated into the pressure vessel, or may be placed in contact with the pressure vessel for the duration of the rotational moulding process.