摘要:
Method of manufacturing a container (2) by stretch-blow molding in a mold (8) from a blank (3) of plastic material, which comprises the operations consisting of: measuring the pressure prevailing inside the blank (3) during a pre-blowing phase; detecting an instant corresponding to a local minimum pressure in the blank (3); placing in memory the instant at which said minimum pressure occurs as well as the corresponding pressure prevailing in the blank (3); comparing the instant and the pressure of the detected minimum with, respectively, a predetermined instant and pressure of a theoretical minimum pressure; if the measured minimum and the theoretical minimum do not coincide, ordering a modification of at least one of the following parameters: pre-blowing pressure, pre-blowing flow rate, stretching speed, heating temperature.
摘要:
The invention relates to a method for producing a vessel (2) by blowing in a mould (11) from a preform (3) made of a plastic material, comprising the following steps: placing the preform (3) into the mould; at a predetermined moment, called pre-blowing cue (tP), controlling the opening of an electrovalve (22) for establishing a communication between the inside of the preform (3) and a source (20) of gas at a predetermined pre-blowing pressure (PP); measuring the pressure (P) inside the preform (3); at a predetermined moment, called blowing cue (tS) and following the pre-blowing cue (tP), controlling the opening of an electrovalve (26) for establishing a communication between the inside of the preform (3) and a source (24) of gas at a predetermined blowing pressure (PS) higher than the pre-blowing pressure (PP); memorising the variations of the pressure (P) inside the preform (3) at least during the interval between the pre-blowing cue (tP) and the blowing cue (tS); detecting in said interval a so-called expansion end moment (tC) from which the pressure in the preform (3) increases in a linear manner, advancing the blowing cue (tS) according to the expansion end moment (tC).
摘要:
A method of manufacturing a container from a blank in a stretch blowing assembly equipped with a mold provided with a wall and a mold bottom axially movable between an extended position and a retracted position and a stretch unit having a rod axially movable with respect to the wall and a device for controlling the movement of the rod. The method involves a stretch blowing phase; a boxing phase during which the mold bottom, initially in the extended position, is moved towards its retracted position, the boxing phase having a retraction operation including controlling a movement of the rod in synchronization with the movement of the mold bottom, or releasing the rod to allow the free axial movement thereof.
摘要:
Method of manufacturing a container from a blank of plastic material, within a mold provided with a wall defining a cavity with the impression of the container, and a mold bottom that is movable with respect to the wall between a retracted position and a deployed position in which it extends protruding into the interior of the cavity in order to form a hollow recess in the container. The method includes inserting the blank into the mold; a pre-blowing operation including injecting a fluid under pressure into the blank, at a pre-blowing pressure; a blowing operation including injecting a fluid under pressure into the blank at a blowing pressure that is greater than the pre-blowing pressure; and a boxing operation, initiated prior to the blowing operation, and including moving the movable mold bottom from its retracted position to its deployed position.
摘要:
A method of measuring the wall temperature of a container blank, including the following operations: inserting a temperature probe into the blank in motion, upon completion of the operation of heating the blank in an oven; maintaining the probe in the blank in motion for a predetermined time; making a temperature measurement by the probe maintained in the blank without contact with the inner wall of the blank; and storing the temperature or the temperature profile thus measured.
摘要:
A method of manufacturing a container from a blank in a stretch blowing assembly equipped with a mold provided with a wall and a mold bottom axially movable between an extended position and a retracted position and a stretch unit having a rod axially movable with respect to the wall and a device for controlling the movement of the rod. The method involves a stretch blowing phase; a boxing phase during which the mold bottom, initially in the extended position, is moved towards its retracted position, the boxing phase having a retraction operation including controlling a movement of the rod in synchronization with the movement of the mold bottom, or releasing the rod to allow the free axial movement thereof.
摘要:
A method of measuring the wall temperature of a container blank, including the following operations: inserting a temperature probe into the blank in motion, upon completion of the operation of heating the blank in an oven; maintaining the probe in the blank in motion for a predetermined time; making a temperature measurement by the probe maintained in the blank without contact with the inner wall of the blank; and storing the temperature or the temperature profile thus measured.
摘要:
Method for producing a vessel (2) by blowing in a mould (11) from a preform (3) made of plastic material, comprising the operations consisting in: introducing the preform (3) into the mould; at a predetermined moment, called pre-blowing cue (tP), controlling the opening of an electrovalve (22) for establishing a communication between the inside of the preform (3) and a source (20) of gas at a predetermined pre-blowing pressure; measuring the pressure (P) inside the preform (3); detecting the so-called real moment (tA), of the beginning of the pre-blowing, at which the (P) in the preform (3) starts to increase; comparing this moment (tA) with a theoretical pre-blowing beginning moment; if the real moment (tA) of the beginning of the pre-blowing follows the theoretical pre-blowing beginning moment, advance the pre-blowing cue (tP); if the real moment (tA) of the beginning of the pre-blowing precedes the theoretical pre-blowing beginning moment, delay the pre-blowing cue (tP).