Patent ID: 6837086

Claim:
A hot isostatic pressing method for heating/pressing a workpiece using a pair of high-pressure vessels and using a pressure medium gas, the method comprising the steps of: heating and pressing workpieces in a first high-pressure vessel which is one of said pair of high-pressure vessels; placing a workpiece in a heating state in a second high-pressure vessel which is the other thereof, while heating and pressing the workpieces in said first high-pressure vessel; reducing the internal pressure of said first high-pressure vessel, after termination of heating and pressing of the workpieces in said first high-pressure vessel; pressing the interior of said second high-pressure vessel, while reducing the internal pressure of said first high-pressure vessel; and heating and pressing the workpieces in said second high-pressure vessel, said step of pressing the interior of said second high-pressure vessel and reducing the internal pressure of said first high-pressure comprising: communicating the interior of said first high-pressure vessel with the interior of said second high-pressure vessel to thereby pour the pressure medium gas released from said first high-pressure vessel into said second high-pressure vessel; and sucking out the pressure medium gas from said first high-pressure vessel by a compressor and pouring the pressure medium gas pressed by the compressor into said second high-pressure vessel, after internal pressure of said first high-pressure vessel and internal pressure of said second high-pressure vessel have assumed a nearly balanced state.