Profiled workpieces made of plastic, rubber or aluminum are required in the construction of vehicles (door and window seals, aluminum spaceframes), in the building trade (window profiles) and in automation systems (belt profiles, assembly modules). In the extrusion process, complex profiles can be manufactured at a comparatively low price. In addition to the form tool, the mold pressure, pressing speed and surface roughness also influence the final form of the workpiece.
It usually takes only several hours to manufacture a batch. Since large quantities are often produced, it is essential to check the quality of such workpieces as quickly as possible after they are pressed. Time-consuming manual programming is therefore out of the question. The CAD data must serve as a foundation. There are basically two possibilities. The measurement plans can be created either immediately before manufacturing the batch or during the design process via Werth Cad-Offline® programming. The precondition for this is, however, that quality assurance is a component of the production or production planning operations. In most cases, the operators of the measuring machines are not adequately qualified to deal with complex coordinate metrology tasks. Help is provided in the form of suitable operator prompting and graphic output of the measurement record in the form of a drawing with the actual dimensions. Special standards for aluminum extrusion molding (tolerances) and plastics (special linkage of contours) must be taken into consideration when programming the measuring software.
For fast inspection of profiles, optical scanning can also be combined with the ToleranceFit® software. In this method, the contour of the parts is checked with a gage. The prerequisite by the design for achieving this is to convert the form and size tolerances usually specified department in numerical form to a contour-related tolerance zone system (Fig. 59) which is better adapted to the manufacturing process.