Abstract: Trafficked surfaces built on foundations which remain substantially undisturbed during seasonal climatic cycles, particularly in permafrost and near permafrost regions where considerable disturbance of the ground beneath foundations is otherwise common. The foundations include combinations of insulation layers, heat sinks and/or thermal bleeds which dampen and prevent the cyclic climatic seasonal variations from affecting the earthen support under the foundations, in both cut and fill sections, and in embankments and backfills adjacent the sections.
Abstract: An arrangement of insulating, thermal absorbing and/or dissipating elements controlling heat flow between a member and its environment. In certain permafrost environments, for example, one or more elements of the system can include a heat sink and/or a thermal bleed where the member is heated. The arrangement controls heat flow from a heated member at such a rate that the total heat transfer does not exceed the limits of the residual heat capacity of permafrost below the freezing point thereof during cyclic climatic influences. The arrangement takes advantage of the fact that artificial heat from the heated member can be controlled, while natural solar heat is balanced by the seasons. The elements also serve to maintain relatively stable temperature differentials between heated or cryogenic materials and their adjacent ground support, so there is a minimal effect of one on the other.
Abstract: Apparatus for rapidly making thermoplastic containers wherein the resultant containers can, if desired, be multilayered for vapor or gas barrier or other reasons, or be oriented for toughness and improved stress crack resistance. The apparatus takes a measured amount of thermoplastic material which is lubricated, heated and forged into a desired shape preform with a predetermined lip configuration. The center portion of each said preform is maintained at a forming temperature while the peripheral portion thereof is clamped and rapidly brought below the softening point of the plastic resin. The preform can then be immediately thermoformed into a container having a desired shape and size, and cooled. If desired, the preform can be forged, cooled and recovered for a subsequent thermoforming operation or can be a finished article itself.
Type:
Grant
Filed:
January 14, 1974
Date of Patent:
March 30, 1976
Assignee:
The Dow Chemical Company
Inventors:
Ralph E. Ayres, Kenneth J. Cleereman, Walter J. Schrenk