Heat-insulating structure

#This invention relates to a heat-insulating structure for protecting a zone or a portion of a wall or the like against the effects of a high-temperature atmosphere. The advantage of this structure lies in the fact that it can readily be adapted to the shape of the zone to be protected, especially within an annular space.

#The invention applies more particularly although not in any exclusive sense to the case in which the wall to be protected is placed within a hazardous and corrosive atmosphere and even more especially in an atmosphere of aerosols or vapor of a liquid metal and especially liquid sodium within a fast reactor vessel.

#To this end, the structure under consideration is constituted by a plurality of elements each formed by two sectional members of substantial length, the structure being distinguished by the fact that the elements aforesaid are mounted in juxtaposed relation in the line of extension of each other, the two sectional members of each element being engaged one inside the other with a small clearance space between their parallel faces, a flexible packing of metallic material being enclosed between the sectional members in such a manner as to ensure that said members can work in pairs both along the length and in the direction of engagement of these latter.

#Further characteristic features of a heat-insulating structure in accordance with the invention will become apparent from the following description of a number of examples of construction and application which are given by way of indication and not in any limiting sense, reference being made to the accompanying drawings, wherein:

#FIG. 1 is a diagrammatic view in perspective and in partial cross-section of the structure under consideration, which illustrates the shape of the constituent elements of said structure;

#FIG. 2 illustrates an alternative form of construction;

#As is apparent from FIG. 1, the structure under consideration is constituted by the juxtaposition of a number of elements 1 which extend along the length of said structure, especially in order to constitute a continuous or non-continuous casing of annular shape or the like. These elements 1 are essentially constituted by two sectional members 2 and 3 respectively which are adapted to engage one inside the other and accordingly have the shape of a wide U. The parallel side flanges 4 and 5 of said section members slide with respect to each other and form between them a narrow clearance space which is capable of trapping the vapor or aerosols in the atmosphere which surrounds the structure. Within the space limited by the two sectional members which are thus interengaged, there is mounted a flexible stack of wire fabric or wire mesh elements 6 which have a certain degree of elasticity and constitute an effective thermal barrier across the structure. As an advantageous feature, the stack of wire fabric or wire mesh elements incorporates a series of small plates 7 which are parallel to the opposite bottom portions of the sectional members 2 and 3.

#In accordance with one arrangement which is characteristic of the invention, each sectional member is provided at one end with an extension 8 having a cross-section which is slightly smaller than that of the sectional member in the remainder of its longitudinal development. This accordingly permits the interengagement of two adjacent sectional members along the length of the structure, which is in turn intended to permit the interassembly of the structural elements 1. The structure can consequently be given the desired length and can more closely conform to the shape of a zone or wall to be protected. In order to simplify the drawings, only the extension 8 of the sectional member 2 has been illustrated in the figure. It is readily apparent that a similar arrangement can be contemplated for the sectional member 3 so as to permit the engagement of this latter within the adjacent sectional member of the adjacent structural element.

#In another alternative embodiment which is illustrated in FIG. 2, the sectional member 2 for example can be provided in its side flanges 4 and 5 with open slots 8' so as to permit engagement within the adjacent sectional member and so on from one member to the next by virtue of the elasticity provided by said slots. Finally, in another embodiment which is illustrated in FIG. 3, the sectional members have an L-shaped cross-section which may or may not be provided with portions for interengagement of these latter. It is apparent from this figure that the sectional members 2 and 3 serve to confine the flexible stack of wire fabric or wire mesh elements 6 without entailing the need for interengagement. In consequence, the sectional members are readily capable of relative displacement if the need should arise. On the other hand, in two successive structural elements 1, the sectional members 2 and 3 respectively can comprise extensions 8 which may or may not have slots 8'. The assembly thus permits relative displacement of the sectional members along the length of the structure.