One of the main reasons for the success of CDs as a low-cost medium for data and pictures is the fact that their production is generally fully automatic. With billions of CDs being manufactured each year, it is virtually impossible to maintain the output rate and the product quality by conventional methods.

For this reason, the entire manufacturing process, from the supply of granulate to the moulding machine to the labelling and quality control of the finished CDs, is today fully automated. Once the plastic disk has been injection-moulded from the granulate, it is a precision part which is easily damaged and which ahs to be moved successively and, above all, precisely from one station to the next of the production process. This cannot be done easily with conventional mechanical/pneumatic transport and handling devices and the safe and damage-free handling of the disks presents major problems. Vacuum-assisted handling of the parts, in contrast, can easily meet all requirements.

For this reason, the product range of the vacuum specialists at J. Schmalz GmbH in D-72293 Glatten includes a wide selection of round suction pads and special annular pads for the CD industry. In addition, the product group "vacuum components" includes many vacuum generators, vacuum switches and monitoring devices, which means that a perfectly matched vacuum system for a CD production plant can be assembled from the products of s single supplier of components and systems.

A very good example of this is the CD production facilities of STEAG, one of the market leaders in this sector. The production facilities consist of various modules for the various production processes, connected together by so-called transfer stations. Since mechanical grippers could distort and damage the CDs and in many cases are not fast enough for the short machine cycles, STEAG relies completely on Schmalz vacuum technology in the form of suction pads.

Distortion and damage are thus impossible and the handling system can operate at the short cycle times of the production machines. Suction pads made of silicone are the preferred solution for the safe handling of CDs. Depending on the application, either flat, round suction pads or special annular pads are used. Flat suction pads are sufficient for some handling sequences. In other cases, such as those requiring a higher suction force, make it necessary to use annular pads with which the CDs or DVDs are gripped centrally, around the centre hole.. This is done with a considerably higher suction force and with uniform distribution of the force on the CD/DVD disks. The higher suction forces and the very fast reaction times permit production to be carried out at the maximum possible speed and with very dynamic movements. In order to ensure that the suction pads designed especially for the handling of CDs, such as the flat pad type SGA 7 SI and the annular pad type SGR 31 SI, can operate permanently at the top end of their performance range, STEAG uses vacuum switches such as the type VS-V-A-PNP for the continuous monitoring of the vacuum values. STEAG can thus produce, transport and handle CDs and DVDs safely at very high speeds – a prerequisite for punctual delivery and economic manufacture of optical storage media.