Thermally insulated pipe

Claim 2

A pipe system comprising: a. a first unit comprising a thermally insulated asbestos-cement fluid conduit; b. at least one end portion on said first unit; c. a second unit comprising a thermally insulated asbestoscement fluid conduit; d. at least one end portion on said second unit; e. a fluid-impervious, chemical-resistant coating on the inner surface of each of said thermally insulated asbestos-cement fluid conduits and on the outer surface of each of said end portions; f. an asbestos-cement thread free coupling having a pair of spaced annular grooves in the inner surface thereof and a fluid-impervious, chemical-resistant coating on the inner surface of said coupling between said grooves and on at least some of the surfaces defining said grooves; g. each of said fluid-impervious, chemical-resistant coatings being continuous in both the circumferential and longitudinal directions; h. an annular resilient gasket seated in each of said grooves; and i. each of said end portions being inserted into said asbestoscement coupling so that each of said annular resilient gaskets is deformed to effect a fluidtight seal between said coating on the outer surface of each of said end portions and said fluidimpervious chemical-resistant coating on the surfaces of each of said grooves.

Claim 3

Thermally insulated pipe comprising: a. a first and a second asbestos-cement pipe in coaxial relationship; b. said first asbestos-cement pipe having an outside diameter less than the inside diameter of said second asbestos-cement pipe so as to provide an annular space between said first and second asbestos-cement pipes; c. thermal-insulating material positioned in said annular space; d. said thermal-insulating material being in contact with the outer surface of said first asbestos-cement pipe and the inner surface of said second asbestos-cement pipe and supporting said first and second asbestos-cement pipes in said coaxial relationship; e. said first asbestos-cement pipe having a fluid-impervious coating on its inner surface extending along its entire axial length and said second asbestos-cement pipe having a fluid-impervious coating on its inner surface extending along its entire axial length to prevent fluid carried through said first pipe and moisture from around said second pipe from passing radially into said annular space containing said thermal-insulating material and f. means extending between the outer surface of said first asbestos-cement pipe and said inner surface of said second asbestos-cement pipe and providing a fluid seal adjacent the axial extremities of said thermal-insulating material.

Claim 4

Thermally insulated pipe comprising: a. a first and a second asbestos-cement pipe in coaxial relationship; b. said first asbestos-cement pipe having an outside diameter less than the inside diameter of said second asbestos-cement pipe so as to provide an annular space between said first and second asbestos-cement pipes; c. thermal-insulating material positioned in said annular space; d. said thermal-insulating material being in contact with the outer surface of said first asbestos-cement pipe and the inner surface of said second asbestos-cement pipe and supporting said first and second asbestos-cement pipes in said coaxial relationship; e. said first asbestos-cement pipe having a fluid-impervious coating on its inner surface extending along its entire axial length and said second asbestos-cement pipe having a fluid-impervious coating on its inner surface extending along its entire axial length to prevent fluid carried through said first pipe and moisture from around said second pipe from passing radially into said annular space containing said thermal-insulating material and f. means extending between the outer surface of said first asbestos-cement pipe and said inner surface of said second asbestos-cement pipe and providing a fluid seal adjacent the axial extremities of said thermal-insulating material.

Claim 5

A pipe system comprising: a. a first and a second asbestos-cement pipe in coaxial relationship; b. said first asbestos-cement pipe having an outside diameter less than the inside diameter of said second asbestos-cement pipe so as to provide an annular space between said first and second asbestos-cement pipes; c. thermal-insulating material positioned in said annular space; d. said thermal-insulating material being in contact with the outer surface of said first asbestos-cement pipe and inner surface of said second asbestos-cement pipe and supporting said first and second asbestos-cement pipes in said coaxial relationship; e. said first asbestos-cement pipe having a longitudinal length greater than said second asbestos-cement pipe so as to provide at least one end portion for said coaxial first and second asbestos-cement pipes; and f. means on the outer surface of said end portion for cooperation with an asbestos-cement coupling for joining adjacent pipes an asbestos-cement coupling having at least one annular groove in the inner surface thereof; g. an annular resilient gasket seated in said groove; h. said end portion being inserted into said coupling so that said annular resilient gasket is deformed to effect a fluidtight seal between said coupling and said end portion; i. said coupling having an outside diameter substantially equal to the outside diameter of said second asbestos-cement pipe.

Claim 6

A pipe system comprising: a. a first and a second asbestos-cement pipe in coaxial relationship; b. said first asbestos-cement pipe having an outside diameter less than the inside diameter of said second asbestos-cement pipe so as to provide an annular space between said first and second asbestos-cement pipes; c. thermal-insulating material positioned in said annular space; d. said thermal-insulating material being in contact with the outer surface of said first asbestos-cement pipe and inner surface of said second asbestos-cement pipe and supporting said first and second asbestos-cement pipes in said coaxial relationship; e. said first asbestos-cement pipe having a longitudinal length greater than said second asbestos-cement pipe so as to provide at least one end portion for said coaxial first and second asbestos-cement pipes; and f. means on the outer surface of said end portion for cooperation with an asbestos-cement coupling for joining adjacent pipes an asbestos-cement coupling having at least one annular groove in the inner surface thereof; g. an annular resilient gasket seated in said groove; h. said end portion being inserted into said coupling so that said annular resilient gasket is deformed to effect a fluidtight seal between said coupling and said end portion; i. said coupling having an outside diameter substantially equal to the outside diameter of said second asbestos-cement pipe.

Claim 7

A pipe system as defined in claim 3 and further comprising: a. a fluid-impervious, chemical-resistant coating on the inner surface of said first and second asbestos-cement pipes and said coupling.

Claim 8

A pipe system comprising: a. a first and a second asbestos-cement pipe in coaxial relationship; b. said first asbestos-cement pipe having an outside diameter less than the inside diameter of said second asbestos-cement pipe so as to provide an annular space between said first and second asbestos-cement pipes; c. thermal-insulating material positioned in said annular space; d. said thermal-insulating material substantially filling said annular space between said first and second asbestos-cement pipe; e. a fluid-impervious coating on the inner surface of said first and second asbestos-cement pipes extending along the entire axial length of each of said asbestos-cement pipes adapted to prevent fluid carried through said first pipe and moisture around said second pipe from passing radially into said annular space containing said thermal insulation.

Claim 9

A pipe system comprising: a. a first and a second asbestos-cement pipe in coaxial relationship; b. said first asbestos-cement pipe having an outside diameter less than the inside diameter of said second asbestos-cement pipe so as to provide an annular space between said first and second asbestos-cement pipes; c. thermal-insulating material positioned in said annular space; d. said thermal-insulating material substantially filling said annular space between said first and second asbestos-cement pipe; e. a fluid-impervious coating on the inner surface of said first and second asbestos-cement pipes extending along the entire axial length of each of said asbestos-cement pipes adapted to prevent fluid carried through said first pipe and moisture around said second pipe from passing radially into said annular space containing said thermal insulation.