Abstract: A method for treating articles with heat and pressure is disclosed. The articles are placed in an isostatic press, the press is evacuated of air and thereafter filled with an inert gas, the pressure and temperature of which is raised to predetermined levels. These predetermined levels are maintained for a period of time sufficient to effect the treatment, and thereafter the inert gas is circulated to promote cooling of the gas and reduce the cooling time of the press and the article treated.

Abstract: An apparatus for treating articles by heat and pressure and then cooling by forced circulation may have a pressurized heated chamber for holding such items to be treated, this chamber being positioned within a cooled, pressure sustaining enclosure, a pressure developing mechanism may be positioned at one side of this enclosure and may include a valving function for selectively drawing inert gas into the enclosure and into the heated chamber the heated chamber including a wall having a plurality of openings spaced throughout into the item-holding chamber, a passageway may extend from one end of this item-holding chamber, past the cooled area of the sustaining enclosure and onto the pressure developing mechanism whereby the valving function may be selectively operated allowing the pressure developing mechanism to circulate the gaseous medium within the apparatus more evenly and uniformly over all items held within the chamber, the heating operation of the chamber being selectively disabled during this circulati

Abstract: A method of and apparatus for treating articles with heat and pressure is disclosed. Included in the apparatus is a furnace in which the articles are to be treated. The articles are placed in the furnace and, the furnace is evacuated, then filled with an inert gas the pressure and temperature of which is raised to predetermined levels. These predetermined levels are maintained for a period of time sufficient to effect the treatment, and, thereafter the inert gas is circulated to promote cooling of the gas and reduce the cooling time of the furnace and the article treated.

Abstract: The disclosed invention describes an apparatus and method for bringing a system having high interactive portions to a predetermined temperature distribution. The invention includes a difference controller which provides, through two separate drivers, a fixed total amount of energy to the system being controlled. If the system being controlled also has a long cycle time, second and third temperature controllers may be used to bring the system to the equilibrium temperature with a minimum amount of overshoot. The invention is particularly advantageous when used in connection with a high pressure, high temperature vessel useful in growing quartz crystals.

Abstract: The invention relates to means for establishing an equalized pressure across the insulating sheath of a hot isostatic press system. Tubes are positioned in the outer, insulation portion of the sheath to provide a substantially resistance free passage between a source of high pressure gas input to the system and the upper portions of the sheath. The invention also tends to reduce convection currents in the furnace chamber.

Abstract: An electrically heated furnace assembly, suitable for a hot isostatic press, having windings of one or more resistance heating elements, helically wound about the longitudinal axis of the furnace assembly; rigid insulating sleeves, enclosing the heating elements and substantially covering their surfaces; the insulating sleeves abutting against the leading and trailing edges of one another and against the outer, upper and lower surfaces of one another; and a spiral shelf provided about the longitudinal axis of the furnace assembly, underlying the heating elements, and abutting against the outer lower surfaces of the insulating sleeves which enclose the lowermost winding of the resistance heating elements.

Abstract: The disclosed invention describes an apparatus and method for bringing a system having high interactive portions to a predetermined temperature distribution. The invention includes a difference controller which provides, through two separate drivers, a fixed total amount of energy to the system being controlled. If the system being controlled also has a long cycle time, second and third temperature controllers may be used to bring the system to the equilibrium temperature with a minimum amount of overshoot. The invention is particularly advantageous when used in connection with a high pressure, high temperature vessel useful in growing quartz crystals.