Common problems and Countermeasures in the cutting

Common problems and Countermeasures in the slitting process of white card board

first, the most common printing method of cut edge

flat paper board is offset printing, so it is necessary to prevent paper dust and other particles from entering the printing machine with the paper as much as possible. An important aspect of the quality of slitting paperboard is to ensure that there is no paper dust on the cutting edge. The following measures can minimize paper dust:

select the most appropriate material and angle of the paper cutter according to the cut cardboard; The paper cutter should be replaced on time; Reasonably adjust the base of the paper cutter (knife edge, inclination, knife edge overlap, knife pressure, etc.), and the base of the paper cutter should be repaired and maintained on time

during the whole paper cutting process, the pressure of the conveyor belt should be suitable and as stable as possible

install the trimming pipe correctly to minimize the pulling force during trimming

the roll that needs to be cut should be as round as possible to ensure that the tension remains unchanged after the cardboard is pulled out, and the activity contraction and supply and demand state continue to be redundant

when replacing a new drum for slitting, ensure that all four sides are centered

when cleaning the machine, pay particular attention to the dust-free cleaning of the slitting knife. Deal with static electricity

the slitting workshop should be equipped with air conditioning

good slitting machines usually have the function of trimming, so that the cardboard can get clean four sides and can be neatly and beautifully stacked on the pallet. But sometimes customers will ask not to trim edges, so as to reduce waste. However, generally, the cardboard needs to be trimmed during slitting, and the edge of the drum is likely to be slightly damaged during transportation. Only by trimming can we ensure that there will be no problems due to the uneven cardboard when entering the printing machine

II. Indentation

indentation is mainly caused by the inconsistent speed of conveyor belt, windlass, belt, straightener, etc. Therefore, all transmission devices should be consistent with the rotation speed of the conveyor belt (whether it is in contact with the upper surface of the paper or the lower surface of the paper). At the same time, it is necessary to avoid the slipping of the transmission wheel, because they may also cause the change of the shape of the cardboard. In addition, when adjusting the spacing of rotating wheels, the factor of paperboard thickness should be considered

when stacking paper, use the air extraction brake to reduce the indentation. The shape and structure of the windlass must be adjusted correctly when using the mechanical brake. The material of the conveyor belt must be suitable for the matte paperboard (the material must be anti slip), especially when the speed is inconsistent, the surface layer of the paperboard is most sensitive to the constant temperature and humidity control system used in the operation process of all instruments

in places that are not connected, such as the paper receiving table behind the driving wheel, the place where paper is stacked and received, a blower should be used to reduce friction. If you carefully observe the traces left by the gate at the paper stack, you can see them with the naked eye. Properly adjusting the paper cutting can reduce the impact

III. surface fracture

the closer the cardboard is to the core, the greater the degree of bending. It is very important to have anti bending equipment for the paper cutter. At the same time, the cardboard part closest to the roll core cannot be used. The thicker the cardboard or the smaller the diameter of the roll core, the more cardboard is discarded at the roll core. A 12 inch (306mm) diameter core can minimize problems related to surface cracking

the anti bending windlass should be equipped with bearings and have a large enough diameter to prevent surface cracking. From experience, the diameter of the reverse bending windlass should reach 60mm-70mm to avoid the surface fracture of the FBB with a thickness of 6001xm. Of course, if the weight of the slitting white chuck is low, a smaller reverse bending windlass can also be used. In addition, the reverse bending windlass group can also be used for reverse bending treatment in several different places

special attention should be paid to reverse bending of thick or long-standing paperboard

in addition, special attention should also be paid to when a whole roll is to be cut

drive wheels with large bending force should be avoided, and the minimum diameter of the drive pulley should not be less than 100mm

there are various types of slitting machines in the market, including those specially used for cardboard slitting and those used for cutting a variety of materials. When cutting different materials, the slitter needs to be adjusted appropriately to ensure that the paper being cut has the best quality. Once there is a customer complaint about cutting cardboard, in addition to the basic information, the most important thing is to correctly sample and send it to the paper factory. Generally speaking, the following information must be provided: a full printed paper sample to show the problem; When the problem occurs, use adhesive tape to stick up the residue on the relevant equipment of the printing machine, otherwise the following adverse consequences may occur, and put the adhesive tape into a plastic bag and send it out together with the paper sample; There is no printed paperboard (cut into small strips) to show the edges with paper dust; Avoiding these two requirements is contradictory. It is not necessary to use the way of rolling up to send the paper sample, and it is best to use the way of folding. (end)