Apparatus for generating impulse-dynamic process forces, comprising: - a pressure chamber in which pressurised hydraulic medium is arranged; - means for temporarily increasing the pressure of the hydraulic medium located in the pressure chamber; - a connecting chamber arranged downstream of the pressure chamber and connected thereto; - a bolt chamber (30; 30') arranged downstream of the connecting chamber and connected thereto; - a stepped piston arranged so as to be displaceable in the connecting chamber, which piston has a valve body for closing an orifice connecting the pressure chamber to the connecting chamber, and a piston portion facing the bolt chamber (30; 30'), by means of which piston portion a transmission space of the connecting chamber between the piston portion and the bolt chamber (30; 30') is sealed with respect to the side of the connecting chamber remote from the bolt chamber (30; 30'), the transmission space having pressurised hydraulic medium arranged therein; and - an impact bolt arranged so to be displaceable in the bolt chamber (30; 30'), which impact bolt has a first bolt portion with a larger cross-section and a second bolt portion with a smaller cross-section, the first bolt portion sealing an interior space of the bolt chamber (30; 30') that surrounds the second bolt portion with respect to the connecting chamber, and - at least one pressure reservoir (37; 38) containing pressurised pressure medium, which pressure reservoir is connected to the bolt chamber (30; 30') and is in communicating connection via a connection port (37b, 38b, 39b) with the interior space of the bolt chamber (30; 30'). characterised in that the opening cross-section of the at least one connection port (37b, 38b, 39b) tapers in a direction away from the stepped piston. - a pressure chamber in which pressurised hydraulic medium is arranged; - means for temporarily increasing the pressure of the hydraulic medium located in the pressure chamber; - a connecting chamber arranged downstream of the pressure chamber and connected thereto; - a bolt chamber (30; 30') arranged downstream of the connecting chamber and connected thereto; - a stepped piston arranged so as to be displaceable in the connecting chamber, which piston has a valve body for closing an orifice connecting the pressure chamber to the connecting chamber, and a piston portion facing the bolt chamber (30; 30'), by means of which piston portion a transmission space of the connecting chamber between the piston portion and the bolt chamber (30; 30') is sealed with respect to the side of the connecting chamber remote from the bolt chamber (30; 30'), the transmission space having pressurised hydraulic medium arranged therein; and - an impact bolt arranged so to be displaceable in the bolt chamber (30; 30'), which impact bolt has a first bolt portion with a larger cross-section and a second bolt portion with a smaller cross-section, the first bolt portion sealing an interior space of the bolt chamber (30; 30') that surrounds the second bolt portion with respect to the connecting chamber, and - at least one pressure reservoir (37; 38) containing pressurised pressure medium, which pressure reservoir is connected to the bolt chamber (30; 30') and is in communicating connection via a connection port (37b, 38b, 39b) with the interior space of the bolt chamber (30; 30').