Abstract: A method for hot hydrostatic pressing by means of working liquid which tends to become unstable within a transition time when in contact with a blank heated to a high working temperature and at a pressure lower than the liquid's stabilization pressure. The pressing of the blank heated to the high working temperature is carried out by raising the pressure of the working fluid to said stabilization pressure for a time shorter than the transition time. This is achieved by surrounding the heated blank by a cover adapted to delay the contact between the heated blank and the working liquid until the pressure in the working chamber is raised.

Abstract: In a high-pressure cylinder with an axial plunger, a seal assembly for scaling the gap between the cylinder wall and the plunger. The assembly is disposed in an annual recess in the wall having an open end and a bottom opposite thereto, and comprises a plunger-sealing ring, a cylinder-sealing ring, a resilient low-pressure ring, and an annual seal holder. The seal holder urges the plunger-sealing ring against the cylinder-sealing ring and the low-pressure ring, and urges the latter two rings against the recess bottom and against each other. The plunger-sealing ring and the cylinder-sealing ring are metallic, their mutual contact surfaces are fitted to each other, and the plunger-sealing ring has sufficient section modulus to ensure that under high pressure the contact and bending deformations at the mutual contact surfaces will be sufficiently small as to keep a tight fit therebetween.

Abstract: In a high-pressure cylinder with an axial plunger, a seal assembly for scaling the gap between the cylinder wall and the plunger. The assembly is disposed in an annual recess in the wall having an open end and a bottom opposite thereto, and comprises a plunger-sealing ring, a cylinder-sealing ring, a resilient low-pressure ring, and an annual seal holder. The seal holder urges the plunger-sealing ring against the cylinder-sealing ring and the low-pressure ring, and urges the latter two rings against the recess bottom and against each other. The plunger-sealing ring and the cylinder-sealing ring are metallic, their mutual contact surfaces are fitted to each other, and the plunger-sealing ring has sufficient section modulus to ensure that under high pressure the contact and bending deformations at the mutual contact surfaces will be sufficiently small as to keep a tight fit therebetween.

Abstract: A method for hot hydrostatic pressing by means of working liquid which tends to become unstable within a transition time when in contact with a blank heated to a high working temperature and at a pressure lower than the liquid's stabilization pressure. The pressing of the blank heated to the high working temperature is carried out by raising the pressure of the working fluid to said stabilization pressure for a time shorter than the transition time. This is achieved by surrounding the heated blank by a cover adapted to delay the contact between the heated blank and the working liquid until the pressure in the working chamber is raised.