The printing rubber roller is the main component of the inking system of the offset printing machine. Its function is to transfer ink to the printing plate, and its quality directly affects the quality of the product. Proper use and maintenance of rubber rollers can not only ensure product quality, but also extend the service life of rubber rollers.
1. Use of rubber roller
(1) Rubber roller pressure. When the rubber roller is working, it should maintain a good contact state and appropriate pressure. Including the pressure between the ink leveling roller, between the plate rubber roller and the ink inking roller, between the plate rubber roller and the printing plate. In the inking system, the size of the contact pressure generally has the following rules; F1> F2> F3> F4> F5, where:
F1——pressure between impression cylinder and blanket cylinder F2——pressure between blanket cylinder and plate cylinder F3——pressure between plate rubber roller and inking roller F4——pressure plate and rubber cylinder Pressure between plate cylinders F5——Pressure between uniform ink rollers
If the pressure between the plate rubber roller and the plate cylinder is too large, the plate will produce bumps, dirty plates, patterns, and reduce the printing plate's endurance; if the pressure is too small, the ink transfer will be poor, resulting in plate graphics Inaccurate or incomplete.
If the pressure between the rubber plate roller and the ink roller is too large, during the clutch pressure process, the rubber plate roller is difficult to rise and fall, and the friction force is large, it is easy to make the rubber roller heat and soften, and accelerate the aging of the rubber roller. Rubber roller crushing causes equipment accidents; if the pressure is too low, not only the ink transfer is bad, but also the rubber roller "jump" during printing.
(2) Ink and ink balance. In the offset printing operation, the ink emulsification is normal and necessary, but the emulsification of the ink caused by "large water and large ink" will form a hydrophilic foundation on the smooth rubber roller, which will deink the rubber roller and dampen the liquid. Corrosion adhesive surface. So on the premise of not sticking dirty, the fountain solution should be as little as possible.
2. Precautions for use
(1) After printing, wash the ink on the rubber roller. For cleaning inks, special cleaning agent should be selected, and check whether paper wool and paper powder are left on the rubber roller. The paper wool and paper powder generally stay on the ink leveling roller, and wipe with a cloth.
(2) For machines with powder spraying devices, the powder spraying will return to the rubber roller with the overprint paper or secondary printing. After cleaning the rubber roller, the powder on the rubber roller should be cleaned.
(3) A hardened film of ink is formed on the surface of the rubber roller, that is, when the rubber surface is vitrified, pumice powder is used to grind it off.
(4) When cracks appear on the surface of the rubber roller, grind it off as soon as possible.
(5) When shutting down, the plate rubber roller and the plate cylinder should be disconnected in time to remove the load to prevent static pressure deformation.
(6) During installation and disassembly, it should be handled with care, and should not collide with the roll neck and the rubber surface, so as not to cause damage to the roll body, bending or damage to the rubber surface; the roll neck and the bearing should be tightly coordinated, and if it is loose, repair welding should be prompt repair.
3. Storage of rubber rollers
The purpose of keeping the rubber roller is to keep it stable in mechanical properties, chemical properties and printability, and extend its service life.
(1) The rubber roller should be stored in a cool, dry, ventilated place, and in a vertical or horizontal state.
(2) When storing horizontally, it should be placed on a shelf. It is strictly forbidden to stack and squeeze the adhesive surfaces on each other to prevent the adhesive surfaces from being deformed and sticking.
(3) Avoid storing with acids, alkalis, oils and sharp hard materials, etc., so as not to corrode and damage the rubber roller.
(4) After the rubber roller is stored for 2 to 3 months, it should be changed in direction to prevent bending and deformation when placed in one direction for a long time, and pay attention to prevent the rust of the shaft head.
(5) It is necessary to make a spare rubber roller, but it should not be spared for too long, because the spare rubber roller will naturally age and take up funds. It should prevent the storage layer from aging, wrinkling, corrosion of shaft head and other phenomena.
(6) The rubber roller stored for a long time should be ground or wiped with pumice powder before use.
4. Effect of rubber roller aging on printing quality
Aging phenomena such as physical damage or wrinkles occur on the surface of the rubber roller, and the impact on the product quality is easy to observe and judge; when vitrification occurs on the surface of the rubber roller. The impact on product quality is not easy to be discovered. The hardened film of ink is produced on the surface of the rubber roller, that is, when the surface is vitrified, the surface of the rubber roller becomes very smooth, and the ink on the surface is uniformly inked, but its performance of absorption and transfer of ink is weakened, and the ink supply is insufficient, which will cause the printing plate to receive ink Unevenness, dark ink at the front and light ink at the back. At this time, the ink roller should be ground or wiped with pumice powder, until the rubber surface does not slip with the touch.
What is Hand Stretch FIlm?
Hand stretch film is considered any Stretch Film Roll that is easily applied by hand. Most hand stretch film rolls weigh less than ten pounds. Hand rolls can come in a variety of widths, but the most common widths are 15 and 18 inch wide rolls. Hand stretch rolls can be applied with or without a stretch film dispenser. The dispensers often have a braking system to help obtain a tighter stretch when applying the film. Our Hand Pallet Wrap comes with a standard 3 inch core size allowing rolls to easily fit any dispensers. View the different hand stretch wraps to choose from below.
Hand Stretch Film (3 inch Core)
This is a standard gauged stretch film that is comparable to any other brand of true gauged stretch film. It is made with a cast extrusion process that uses rollers to cool the film as it is extruded.
This enables a faster extrusion process than blown extrusion, therefore making a more affordable stretch film. Our hand Stretch Wrap offers great stretch, strength, and clarity for a variety of applications.
Micron Hand Stretch Film (3 inch Core)
Our micron stretch film is what we refer to as an equivalent stretch film. Many experts predict a shift in the stretch film industry to equivalent films. They are produced from a different formula than the standard gauged film. This formula allows the equivalent film to be thinner, stronger, and stiffer than standard gauged stretch film.
Many companies welcome the idea of lowering overall stretch costs. We recommend trying a sample if you have never tried an equivalent hand stretch wrap. This will allow you to make an accurate assessment of the film and if it is right for your needs.
Hand Stretch Film,Pallet Stretch Wrap,Hand Roll Stretch Film,Hand Pallet Wrap
Shenzhen Chengxing Packing & Material Co.,Ltd Shenzhen caomu new material products Co., Ltd , https://www.cxpack.com