Method and apparatus for maintaining a minimum temperature in a fluid

#This is the U.S. National Stage of International Application No. PCT/GB2012/051471, filed Jun. 22, 2012, which in turn claims the benefit of and priority to United Kingdom Application No. GB1110569.9, filed Jun. 22, 2011.

#The present invention relates to a method and apparatus for providing one or more layers of a thermally active material in or on a pipe, more especially a flexible pipe. In particular, but not exclusively, the present invention relates to the use of one or more encapsulated or enclosed regions of a thermally active material, that is, a material which is effective in absorbing thermal energy in a first set of conditions and releasing thermal energy in a second set of conditions. The thermally active material is disposed in one or more layers of the flexible pipe body. The thermally active material is, in particular embodiments, a material having a high latent heat on phase change. Suitable materials are also known as phase change materials (PCM). In the present invention, the thermally active material acts as a thermal energy storage reservoir which acts to absorb heat or release “stored” heat in accordance with the temperature of the local environment to which it is subjected.

#The invention relates further to a method and apparatus for preventing or delaying the formation of solids such as waxes or hydrates from a production fluid in a pipe, in particular a flexible pipe.

#Embodiments of the present invention will be described hereinafter, by way of example only, with reference to the accompanying drawings in which:

#FIG. 1 illustrates a flexible pipe body;

#FIG. 2 illustrates a catenary riser, flow line and jumper;

#In the drawings like reference numerals refer to like parts.

#Throughout this specification reference will be made to a flexible pipe. It will be understood that a flexible pipe is an assembly of a portion of pipe body and one or more end fittings in each of which a respective end of the pipe body is terminated. FIG. 1 illustrates how pipe body 100 is formed in accordance with an embodiment of the present invention from a composite of layered materials that form a pressure-containing conduit. Although a number of particular layers are illustrated in FIG. 1, it is to be understood that the present invention is broadly applicable to composite pipe body structures including two or more layers manufactured from a variety of possible materials. It is to be further noted that the layer thicknesses are shown for illustrative purposes only.

#As illustrated in FIG. 1, a pipe body includes an optional innermost carcass layer 101. The carcass provides an interlocked construction that can be used as the innermost layer to prevent, totally or partially, collapse of an internal pressure sheath 102 due to pipe decompression, external pressure, and tensile armour pressure and mechanical crushing loads. It will be appreciated that certain embodiments of the present invention are applicable to ‘smooth bore’ as well as such ‘rough bore’ applications.