Insulated conduit
This application is a continuation-in-part of application Ser. No. 886,243 filed Mar. 13, 1978, now abandoned. 
    
    
     BRIEF SUMMARY OF THE INVENTION 
     There is a need in manufacturing installations, farms, homes, experimental laboratories, governmental installations, solar energy utilization for a comparitively simplified means of providing insulation and protection from the elements for heat, cold or any piping conveying liquid or gaseous materials from one point to another. This system allows the user the option of the installation of a wide variety of piping of various construction and materials without the necessity of purchasing the piping and insulation as a combined unit. An easily installed slide-over arrangement allows for simplified testing of the installation for leakage and provides adequate facilities for expansive forces while undergoing wide variations in temperature. This system is particularly effective and adaptable but not necessarily restricted to subterranean installations where the installation is in direct earth contact. Use of the insulated conduit makes the installation of underground piping in open earth excavations simpler and offers better protection from moisture and penetration by vapor and allows greater economic savings during fabrication and installation of protection for piping than what is presently available. Undesired heat loss is kept to a minimum by providing a unique vapor and insulative protection. The insulated conduit provides a high degree of structural stability, thus offering protection during installation procedures. 
    
    
     BRIEF DESCRIPTION OF THE VIEWS OF THE DRAWING 
     FIG. 1 is a cross section of a length of insulated conduit. 
     FIG. 2 is a cross section of a joint comprised of two individual sections of insulated conduit. 
     FIG. 3 is the spigot end of a length of insulated conduit in cross section. 
     FIG. 4 is a cross section of a 90 degree bend in insulated conduit. 
     FIG. 5 is and end view of the spigot end of a section of insulated conduit. 
     FIG. 6 is an end view of the bell end of a section of insulated conduit. 
     FIG. 7 is a side view of a joint of two separate lengths of insulated conduit. 
     FIG. 8 is a cross section of insulated conduit taken through a resting block. 
     FIG. 9 is a side view with cutaways and a partial section of two lengths of insulated conduit. 
     FIG. 10 is a partial view of the annular joint in two sections of insulated conduit. 
     FIG. 11 is a cross section view of an anchor arrangement. 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 is a section of a length of insulated conduit taken slightly off the circular axis of the conduit. By this means the dead air space 2, is shown and a cross section of the outer wall of the outer insulation jacket 1. The inner structural tubing is shown at the spigot end 3, with the protrusion of the spigot end of the inner structural tube a distance from the plane inscribed by the end of the outer insulation jacket, the length of said distance being determined by the depth 13, of the bell end of the adjoining inner structural tubing. The bell end 5, of the inner structural tube lying in the same plane as the one formed by the circumference of the outer insulation jacket. The outer insulation jacket having an annular tongue configuration 6, at one end and a matching annular groove arrangement configuration 7, at the other end. Said inner structural tubing being constructed of a homogenous, water resistant material such as, but not restricted to poly vinyl chloride plastic tubing which is ordinarily manufactured with accomodating bell and spigot ends so the spigot end of one length may be inserted a certain distance into the bell end of an adjacent length of tubing. The outer insulation jacket 1, being composed of a material such as but not necessarily restricted to an expandable foam type plastic such as styrofoam, urethane, or expanded polystyrene. The ribs, 11 also being composed of said materials and being arranged in a desired manner shape thereby forming the so called dead air space between the inner structural tubing and the outer insulation jacket with the dead air space, 2 formed by the rib arrangement and running the length of the insulated conduit. Said outer insulation jacket is further protected by a membrane, 12 of a relatively moisture or vapor penetrative resistant material such as, but not necessarily restricted to a plastic type material of these characteristics such as tubular polyethylene film. Resting blocks, 8 are provided for support and a resting surface for the inner heat or energy conducting piping 10, and may be constructed of a low friction type material thereby allowing said energy conducting piping freedom of linear motion as required during expansive and contractive variations caused during the transfer of materials or energy. Anchors, 4 composed of appropriate material are fastened by suitable means and at ideal intervals and distances from the individual ends of each section of insulated conduit and thereby provide a means of attachment of a wire, thong or similar material, 9 so adjoining sections may be fastened to each other and held in close approximation in this manner. Linear marking lines, 14 are provided so each section may be assembled in a proscribed circumferential arrangement with the adjoining section thereby assuring alignment of the interior resting blocks.