How to maintain your rollers in top condition ?
- Rollers should be cleaned thoroughly with a roller wash especially at the end of every day’s work. This will prolong the life of the roller and minimize the hardening effect.
- Clean the rollers frequently before the ink starts to dry. Accumulation of dried ink film will cause Glazing.
- Rollers should never be left for long periods in contact because" flats" can form on the soft rollers. Moreover if wash-up has not been completely clean the rollers can stick at contact points with the risk of pieces being top of the surface of the roller when the machine is turned.
- Many rollers become useless because of longtime and/or improper storage. Spare rollers should be rotated with the rollers on the press, at least every six months. This acts as a sort of seasoning, reliving stresses that are inbuilt in roller. The replaced rollers should be cleaned thoroughly and after dusting them with talcum powder and covering them up with the black or brown paper, should be rested horizontally on the journals. The rubberized portion should never contact any other surface. The storage place should be away from direct sunlight and heat.
- While printing smaller jobs on larger machines printers tend to release ink only to cover the print area. This causes the sides of the rollers to run dry generation high temperature and causing heavy wear on the roller ends due to abrasion.
- While fitting the bearings, take care that you do not bend or damage the journal ends by hammering or forcing. Check up the journal ends/bearing seats, sockets and brackets for wear or damage.
- Use the correct technique for mounting the hose on a Dampening Roller. Excessive force may damage the roller by tearing the soft roller from the metal core.
- To avoid "bulging" or "belling" of dampening Rollers place a disc/collar of fibers/plastic, with a slightly smaller diameter than the rubber, at both rubber ends and then sew on the hose ends. Any pressure or pull exerted now will be on the disc and not on the rubber sides.
Further Reading: Rubber proccesing and safety issues