Outdated? Not anymore. Records are back in vogue with music lovers. Especially during the Advent season, many stars release their Christmas collections as LPs (long-playing records). The manufacturers of the round vinyl discs are specialists and are few and far between. With a lot of heart and soul, the company Optimal Media from Röbel/Müritz is one of them. And valve terminals from Festo can be found in their record presses.
Every year Christmas carols play an essential part in getting into the festive spirit. And it is becoming more and more of a trend for artists to release their Christmas album as an LP as well. To transfer the songs onto the vinyl, Optimal Media uses automatic record presses around the clock, many of which are more than 30 years old.
From the biscuit to the vinyl record
Before the actual pressing process starts, an employee uses a polishing cloth to remove dust and dirt from two press moulds, also known as dies, and inserts them into the machine at the top and bottom. Then PVC granulate – the base material of the record – is fed into an extruder via a vacuum line. The extruder has a heated screw, and using friction, pressure and heat, it forms a so-called biscuit, which is placed between the two dies. Now the record label is placed on the biscuit and a stainless-steel pin fixes everything in place.
In the next step, the die is heated with steam, and the raw material is pressed at a pressure of about 200 kg/cm2 and a temperature of about 130°C. This is followed by a short cooling phase in which water cools the dies. Finally, a cutting blade separates the excess material, and a transport arm places the record on a spindle, where it must cool for up to five hours depending on its weight. Meanwhile, the extruder produces another biscuit and the process begins anew.
Reliable machines – a big challenge
Vinyl production is technically very demanding. Each cycle must be the same, but it depends on many parameters such as steam, water, vacuum and temperature of the biscuit. If just one of these main parameters changes minimally, the disc will not be usable. This makes it all the more important that the automatic presses function reliably.
This can be a big challenge with the old machines. Solenoid valves are usually installed as standard, all of which are individually controlled. Seven years ago, Optimal Media therefore retrofitted all of its automatic machines with Festo technology. The MPA-L valve terminals with fieldbus connection control all of the presses’ vacuum and pneumatic components. They also monitor air consumption, which was able to be significantly reduced as a result. Optimal Media is thus perfectly equipped to handle the production of Christmas records, which usually starts in August so that the LPs are on the shelves in good time.
See the process of record production: