초록 ▼

The invention is a fluid heated drum especially well adapted for use with a drum press in which high press roll nip loading and high heat flux to a pressed web are both encountered. A press of this type is disclosed in detail. However, the drum is more broadly useful in any application combining hea

The invention is a fluid heated drum especially well adapted for use with a drum press in which high press roll nip loading and high heat flux to a pressed web are both encountered. A press of this type is disclosed in detail. However, the drum is more broadly useful in any application combining heavy mechanical drum loading and high heat flux through the drum surface. The drum is constructed with a thin outer shell spaced radially apart from an inner cylindrical body. Radial supports provide load bearing connections between the two. The annulus between the shell and inner body may be arranged in various patterns as a conduit for the flow of heating fluid. By using a thin outer shell which does not have to sustain high bending stresses a high rate of heat transfer is permitted. The outer shell may be made of copper or other high thermal flux but lower strength metal to obtain additional heat transfer advantages.

대표청구항 ▼

A drum comprising: an inner cylindrical load bearing drum; an outer cylindrical shell, said shell coaxially surrounding and spaced radially outward and apart from the inner drum to create an annulus between the shell and inner drum, the annulus being closed at each end; radial connections within the

A drum comprising: an inner cylindrical load bearing drum; an outer cylindrical shell, said shell coaxially surrounding and spaced radially outward and apart from the inner drum to create an annulus between the shell and inner drum, the annulus being closed at each end; radial connections within the annulus extending between said shell and said inner drum to secure the shell to the inner drum and transmit any load bearing against the shell to the inner drum, the radial connections being spaced both axially and circumferentially of the inner drum, said radial connections and said shell and said inner drum defining axial fluid flow passages, at least a part of said axial fluid flow passages being within a defined radial distance of the outer perimeter of said shell wherein said radial distance is equal to 1/5√k inches and k is the thermal conductivity of the material of construction of the outer shell expressed in Btu/hr/ft2/unit temperature gradient in °F./ft, said fluid flow passages within said defined said radial distance having a total surface area greater than the shell outer perimeter total surface area. A press comprising a rotatable drum, an endless flexible belt reeved about said drum, and means for guiding and tensioning the belt about the drum to compress a web moving between the belt and drum, said drum further comprising; an inner cylindrical load bearing drum; an outer cylindrical shell, said shell coaxially surrounding and spaced radially outward and apart from the inner drum to create an annulus between the shell and said inner drum the annulus being closed at each end; radial connections within said annulus, extending between said shell and said inner drum to secure the shell to the inner drum and transmit any load bearing against the shell to the inner drum, the radial connections being spaced both axially and circumferentially of the inner drum, said radial connections and said shell and said inner drum defining axial fluid flow passages, at least a part of said axial fluid flow passages being within a defined radial distance of the outer perimeter of said shell wherein said radial distance is equal to 1/5√k inches and k is the thermal conductivity of the material of construction of the outer shell expressed in Btu/hour/ft2/unit temperature gradient in °F./ft, said fluid flow passages within said defined said radial distance having a total surface area greater than the shell outer perimeter total surface area.