How to use the rubber roller of offset press best

How to use the rubber roller of offset press well

rubber roller plays an important role in offset press. The quality of the rubber roller determines the quality of offset printing products, and you will understand why there are such concerns. In the production process, offset printing operators must master the use and maintenance methods of rubber rollers to ensure the quality of printing products

first, the pressure between the cots is too heavy

in the production process, the pressure between the cots and the ink channeling roller is very important. The heavy pressure between the cots will increase the friction between the cots, heat the cots, increase the extrusion and expansion between the cots, accelerate the aging and deformation of the cots, and speed up the emulsification process of ink and water, which is not conducive to the transmission of ink. The solution is: the pressure between the cots should be basically the same as the pressure contacting the layout. Experience is to insert a 1500 wire, 3cm wide stopper between the rubber rollers, and you can feel a certain tightening force

II. Requirements for cleaning cots

generally, we should clean the cots when we are off duty and changing colors to prepare for the next work. In the process of cleaning the cots, sometimes we often ignore the cleaning of the solvent left at both ends of the cots after the cots are cleaned. In this case, the gasoline and ink left at both ends of the cots will gradually accumulate. The residual gasoline, due to the dissolution of some ink, becomes some non-volatile solvent and remains at both ends of the cot. it will slowly penetrate into the cot, damaging the performance of the rubber and accelerating the aging and cracking of the rubber. Therefore, in the production work, we often find that the two ends of the cot are the easiest to crack. Solution: in qualified factories, we should promote the use of car washing water. In this way, both environmental protection and protection cots, improve the durability of cots. In general small factories, after cleaning the cots with gasoline, wipe the residual solvent at both ends of the cots, and then run the machine for a few minutes to make the residual solvent between the cots volatilize fully. And some small offset printing machines (8K, 6K) require that you try not to wash the ink bucket. Remove the rubber roller from the machine (because there are few ink rollers in this machine, it is easy to disassemble and assemble), wipe it with gasoline, and then wipe it with a clean cloth, and then install the rubber roller on the professional color masterbatch of the machine for the next use

III. treatment of cot surface crystallization

when cots are used for a period of time (especially inks commonly added with dry oil), we will find that the cot surface is a little bright, which is cot surface crystallization. The surface crystallization closes the pores on the surface of the cot, which will make the cot lose its ink friendly function, resulting in the uniform transmission cloth of the ink and the emulsification of the ink. The solution is: unload the rubber roller on the machine, lay it flat with a shelf, take the cloth and stick kerosene and pumice powder, wipe the surface of the rubber roller evenly with force, spray water and maintain it for more than 1 week, wipe off the crystallization layer on the surface of the rubber roller, show the rubber color of the original rubber roller, and then wash the kerosene and pumice powder remaining on the rubber roller with car wash water or gasoline, reinstall and adjust the pressure of the rubber roller

IV. maintenance of bearings on COTS

during the high-speed operation of the machine, the wear of bearings on COTS is obvious, especially if the operator pays attention to the maintenance cloth of bearings at ordinary times, the wear is even worse. After the bearings of the cots are damaged to a certain extent, the jumping friction and extrusion of the cots will occur, which will shorten the service life of the cots. And will make the printed products have the phenomenon of "ink, water bar". Therefore, the operator is required to take down the cots every week, grease the bearings, and replace the bearings that are worn badly and rotate poorly. The machine has simple operation, so as to ensure the normal use of the cots

v. impact of rubber roller stacking in the workshop environment

in the production of muggy and humid weather and the environment with flying dust from the surrounding, the high-speed operation of the machine makes the surface temperature of the rubber roller continuously rise, the rubber roller is heating and expanding, and the friction of the rubber roller is increased, which will shorten the service life of the rubber roller

therefore, in qualified factories, offset printing plug-ins are required to install air conditioners to keep the workshop clean and tidy, so that the machine can operate in a good environment. Only in a good workshop environment can high-quality products be produced

source: China tinplate printing