surpose you bought a flexo printing machine from China. And want to print double side at the PE bag or woven sack. May be you will face a problem when seting double side printing. Here, I tell you how to do when you want printing double side at same time.
First. Pass the film according to 4+2,or 3+3 diagram, see attached example drawing. 6+0 and 4+2 film pass diagram is different. So Pass the film correctly is very important.
Second. Setting the impression roller drive direction. because the roller rotate direction has changed when double side printing. So we need to setting it, please check attached picture. Left is for single side printing , right side for double side printing.
Last. Setting the anilox roller rotate direction. Because the impression roller and plate roller have reversed. So now we setting anilox roller. The bearing in the gear of anilox roller is unidirectional. We need remove the gear with bearing. Then reverse the bearing and assmeble it again. Check attached picture:
Till now, you can running the machine correctly. if the anilox roller gear not setting correctly, will like following videos. the gear of anilox roller will not drive.
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