Abstract: A heat insulator for a hot isostatic pressing apparatus including a plurality of non-perforated graphite sheets; a plurality of perforated graphite sheets, each one of the plurality of perforated graphite sheets being sandwiched between and making at least substantially planar contact with, but not being bonded to, adjoining ones of the plurality of non-perforated graphite sheets; and a gas having an extremely low thermal conductivity substantially confined in the perforations in the plurality of perforated graphite sheets.

Abstract: A hot isostatic pressing system including a hot isostatic pressing station having a high pressure container constituted by a vertical pressure-resistant cylinder closed at the top end thereof and a lower lid detachably fitted to the bottom of the pressure resistant cylinder and a treating chamber internally provided with a heater and enclosed by a heat insulating wall, and a mechanism for adjusting an atmospheric gas pressure and temperature of the pressing station into a condition suitable for the hot isostatic pressing of a work item accommodated in the treating chamber; a plurality of auxiliary stations each provided with an opening for receiving from beneath thereof the heat insulating wall of the treating chamber accommodating the internal heater and a work item, a support structure for supporting the heat insulating wall, and a mechanism for cooling the work item and internal heater in an inert gas atmosphere; a carriage for transferring the lower lid and work item or the lower lid, work item, heat insu

Abstract: A heater for use in the HIP apparatus for treating a work item or work items in a high temperature and pressure gas atmosphere by isostatic application of pressure in a heated condition, the heater including at least one heater assembly unit including a meandering heating element arranged into a cylindrical grid-like form having axial slits open alternately at the upper and lower ends thereof; a plurality of radial projections of a predetermined width extending radially outward from the upper ends of the meandering heating element at a number of predetermined positions including terminal ends thereof; a number of mounted holes formed through the radial extensions of the heating element; a number of support columns fixedly erected respectively on retaining members and having a male screw portion at the upper ends thereof respectively protruded upwardly through the mounting holes in the radial extensions of the heating element; and a number of nuts respectively threaded and tightened on the protruded ends of th

Abstract: A method of hot isostatic pressing in which a shaped work immersed in molten glass is subjected to a hot isostatic pressing treatment, the method basically including embedding a shaped item to be worked on in glass powder filled in a crucible; loading the crucible into a movable heating furnace having a heater and a heat insulating structure; charging the furnace into an atmospheric chamber; adjusting the atmosphere in the chamber into a predetermined condition and heating the crucible by the heater to soften and melt the glass in the crucible; transferring the furnace from the atmospheric chamber into a high pressure container while maintaining a high temperature in the furnace; admitting a pressing gas medium into the high pressure container while raising the temperature of the furnace to let the work in the crucible undergo a hot isostatic pressing treatment; and upon completion of the hot isostatic pressing treatment, taking out the furnace from the high pressure container with the work still in loaded st

Abstract: A heater which includes: at least two electrically conductive heating element units having generally a self-standing cylindrical shape and stacked one on another to define a series of at least two cylindrical heating zones, the heating element units each including of a grid-like structure alternately having a vertically disposed portion and a horizontally extending bridge portion; insulator blocks fitted on the ends of stacked upper and lower cylindrical heating element units which meet and which are made of a material having a sufficient electric resistance that will not conduct electric current at a maximum operating temperature of the heating element units; and an annular shaped connector conforming with the ends of the upper and lower heating element units which meet and which is interposed between the insulating blocks on the ends which meet to provide a mechanical connection between the stacked upper and lower heating element units.

Abstract: A high density sintering method for powder molded products by applying preliminary sintering to powder molded products previously molded into a predetermined shape and then applying hot isostatic press process to the sintered products thereby producing high density sintered product which includes the steps of loading the powder molded products into a movable heating furnace equipped with at least one heating means and having a heat insulating structure, introducing the heating furnace into an atmosphere chamber, applying preliminary sintering to the powder molded products in the heating furnace by the heating means while conditioning the inside of the atmosphere chamber to a vacuum or predetermined gas atmosphere, subsequently removing the heating furnace while maintaining the inside thereof at a high temperature from the atmosphere chamber and directly introducing the furnace into a high pressure vessel, thereafter, applying the hot isostatic press process to the sintered products in the furnace while chargi