Described is a method for producing thermoplastic material containers by blow-molding or stretch-blow-molding a hollow body previously heated in an oven and placed in a mold. The method includes a preliminary calibration step of: producing containers on the basis of first control parameters; measuring the wall thickness on extraction from the mold at two or more different heights; storing a reference thickness in a memory unit; modifying at least one control parameter; measuring the wall thickness at two or more different heights after the modification of each control parameter; storing the thicknesses; comparing said stored measured thicknesses with theoretical thicknesses that would have been obtained after modification of the control parameter(s) according to predetermined correction coefficients; and modifying the predetermined correction coefficients so that the thicknesses measured after modification of the control parameter(s) correspond to the theoretical thicknesses that would have been obtained with the aforementioned predetermined coefficients.

Provided is a method for heating a succession of preforms. The method includes heating a body of a first preform using two heating elements that each heat a heated area of the body. The method includes determining a target heating temperature for each heated area according to the container to be produced, measuring the temperature of one of the heated areas of the body upon completion of the heating step, and modifying the heating power of the heating element corresponding to the heated area of the body if the measured temperature of the heated area is different from the target heating temperature. The method further includes heating the body of the other preforms of the succession of preforms with the modified heating power.

Method for forming plastic preforms into plastic containers, wherein a plastic preform is introduced into a blow mould and is expanded into a plastic container by being applied by a flowable medium, wherein the plastic preform is applied by at least two different pressure levels and wherein furthermore preferably a rod-like body is introduced into the plastic preform, in order to expand the plastic preform in its longitudinal direction, wherein a pressure curve and/or a movement curve of the rod-like body being determined by a measuring device during the expansion process, wherein least one of the curves is evaluated by means of a processor device and at least one point or region of this curve which is characteristic of the course is determined.

In a method for monitoring a blow-moulding device for producing a hollow body, the blow-moulding device includes at least one process valve unit for feeding a process fluid into a preform of the hollow body under process pressure, wherein the process valve unit includes at least one electrically operated valve. During a blow-moulding process, at least one value of an electric current of the electrically operated valve is detected. The method and the device allow early recognition of an ageing process of the process valves, in particular their pilot valves, and/or the recognition of the status of valve properties.

A method and apparatus for shaping plastic preforms into plastic containers, wherein at least three different pressure stages are applied to the plastic preforms in order to expand them, wherein the pressure stages are provided by at least three different compressed-air reservoirs, and wherein, additionally, the plastic preforms are stretched in their longitudinal direction by stretching rods, wherein compressed air is returned at least at times from the plastic containers to at least one compressed-air reservoir, and at least one value characteristic of the consumption of compressed air is detected.

Disclosed is a method for operating a forming device for forming plastics material preforms into plastics material containers, wherein the forming device has a movable carrier on which a plurality of forming stations are arranged, wherein each of these forming stations forms plastics material preforms into the plastics material containers by applying a flowable and, in particular, gaseous medium in an operation mode, wherein in the operation mode at least two different pressure levels are applied to the plastics material preforms for the expansion thereof and at least two valves are used for this application, wherein at least one measured value is determined, at least at times, which is characteristic of a switching time and/or a switching time delay of at least one of the valves, wherein this measured value results from a pressure measured value.

A heating system (2) for heating plastic material preforms upstream of a blow molding or stretch-blow molding machine (3), the system comprising a heating module (4) adapted to be crossed by a plurality of preforms (5) advancing along a transport line (14), wherein the heating module (4) is provided with a plurality of heating elements (12, 13) arranged along a plane substantially parallel to a plane containing the axes of the preforms adapted to cross said heating module, wherein the heating module (4) comprises a first heating zone (10), proximal to a support area of the neck of the preforms and comprising at least one first heating element (12) of said plurality of heating elements, and at least one second heating zone (11), arranged adjacent to said first heating zone (10) and at a passage zone of the tubular body of the preforms, and comprising at least one second heating element (13) of said plurality of heating elements, wherein the heating system (2) further comprises at least one first temperature sensor (8) arranged externally to the heating module (4) and at said first heating zone, and at least one second temperature sensor (9) arranged externally to the heating module (4) and at said at least one second heating zone.