Effective suction for newspaper printing

Sev­er­al Ruwac DAV-SB vac­u­ums ensure a clean print­ing process at the Mit­teldeutsche Zeitung print­ing plant in Halle/ Saale — for around 150,000 news­pa­pers per night shift. They con­tin­u­ous­ly vac­u­um up paper dust, off­cuts, etc. and are ide­al­ly suit­ed for pre­cise­ly this purpose.

7:30 p.m. to 2:00 a.m., six times a week: that’s the “work­ing time” of the three gigan­tic press­es that pro­duce around 140,000 copies of the Mit­teldeutsche Zeitung in web off­set print­ing dur­ing these six and a half hours. That’s 21,000 com­plete news­pa­pers per hour, or a good 350 per minute, and it takes about 20 tons of paper — day after day.

It goes with­out say­ing that the numer­ous print­ing, trans­port, cut­ting and fold­ing process­es in the mul­ti-sto­ry, house-sized facil­i­ties also gen­er­ate large quan­ti­ties of paper dust and strips, off­cuts, etc. It is also a mat­ter of course that these waste mate­ri­als are returned to the print­ing plant. It is equal­ly self-evi­dent that these residues must be removed from the print­ing process.

“The paper dust that inevitably aris­es must not set­tle on either the print heads or the paper. Oth­er­wise, we would not be able to guar­an­tee flaw­less printing.”

- Sven Dit­trich, Pro­duc­tion Manager

For this rea­son, there are suc­tion units on every lev­el of the print­ing sys­tems that are direct­ly inte­grat­ed into the pro­duc­tion process and con­tin­u­ous­ly ensure that fine paper dust is imme­di­ate­ly extract­ed, as well as larg­er paper scraps and strips.

The man­u­fac­tur­er has sup­plied these suc­tion units direct­ly with the press­es and they are also inte­grat­ed into the pro­duc­tion process in terms of con­trol tech­nol­o­gy: as soon as a press starts up, the suc­tion units start auto­mat­i­cal­ly and ensure per­ma­nent suction.

The suc­tion units are the DAV-SB series, which was devel­oped from the ground up for vac­u­um­ing up fluff, trim rem­nants, etc. on pro­duc­tion equip­ment and is there­fore also known inter­nal­ly as the “fluff suc­tion unit”. Suc­tion pow­er, vac­u­um and mechan­i­cal design are adapt­ed to strong­ly com­press the vac­u­umed mate­r­i­al in a dust class M fil­ter bag. This means that the vol­ume of the fil­ter can be opti­mal­ly uti­lized. To change the fil­ter, the oper­a­tor only has to lift the vac­u­um clean­er lid and replace the fil­ter bag. A view­ing win­dow in the lid allows the fill lev­el to be checked regularly.

The com­pact units can also fit into con­fined spaces, and they offer con­nec­tion options for an addi­tion­al suc­tion hose. They thus ful­fill a dual func­tion: they con­tin­u­ous­ly extract paper dust from the process, and they are equipped with an addi­tion­al 8‑meter suc­tion hose for easy and con­ve­nient vac­u­um­ing of machines in the vicin­i­ty. Sven Dit­trich: “Instead of using addi­tion­al mobile indus­tri­al vac­u­ums on each lev­el, which we would then have to trans­port from one place to anoth­er, we can vac­u­um and clean every­thing direct­ly on site. That saves us a lot of lug­ging around and ulti­mate­ly the search for a free unit.” All in all, the print shop man­ager’s assess­ment of the vac­u­ums is pos­i­tive: “When you need them, they’re there. Oth­er­wise, you don’t have to wor­ry much about them. That’s the way it should be.”