Gravure machine ink scraper adjusting method

With the development of society advances, the requirement of foreign people more and more is also high. Gravure printing of the main advantage is the image color is rich, color is strong, the main advantages of flexo printing decided the exquisite packing generally ask gravure printing with. But the impact gravure printing quality, there are many factors such as: the influence of the environment, the technical level, the ink operators, the quality of the quality of the equipment, and so on. And ink scraper to print the influence on the quality of flexo ink scraping knife is especially important, not only affect the quality of the adjustment the printing quality, but also to the life of the sword scraping ink produce very big effect.

　　In order to facilitate the sword scraping ink, and ensure the adjustment designed quality, make the plate roll ink can be removed, do not produce the knife wire or version, so the defects scrape ink knife institutions are divided into several functions device component. Its main parts around move channeling scraper device drivers, ink scraping knife clutch pressure device, scraping ink scraping ink, lifting devices knife knife Angle adjustment device and scraper splint devices, etc. Scraping ink around move by sword and there have plenty of individual motor drive, have a plenty of through the main drive the worm gear deceleration later drive; Scrape the sword of clutch pressure is ink by cylinder through the manual directional control valves ventilation to realize, he breathed his last its main functions are make contact or from scraper version roller; Sword scraping ink lifting devices is realized by the super-modulus gear, can realize the pressure regulation; Sword scraping ink Angle adjustment is made to the realization of worm gear and worm, the right Angle of vital importance, Scraper device on plywood, plywood by next plywood, scraper pad and composed of scraper, can it is convenient to adjust the amount of scraper out.


　　Scrape the sword of each part institutions ink function components from different aspects of the printing quality affects the quality. So for the adjustment of the sword scraping ink is vital, and in production practices of long-term found, as long as the sword scraping ink institutions each function device in before printing adjusted, can avoid to produce effect of printing quality defects. The following are some of the sword scraping ink adjustment experience:


　　1. The sword scraping ink and there still is about to realize by eccentric shaft rotation, from left to right to limit a speed limit the sudden change, so from the sword scraping ink per minute of reciprocating mobile number and version roller RPM ratio is an infinite decimal, generally choose 1/7 or 1/9, that can change the sword scraping ink in the trajectory of the version roller, and can the impurity around through scraper and there still carry down, reduce the sword scraping ink line, make better effect. Will eccentric shaft rotation to left, adjust the joint bearing limit thread, make the left of the scaffolds were most compression spring compression value.


　　2. The sword scraping ink is to influence the whole organization rigid printing quality of a major factor, especially high-speed gravure printing. When version roller rotation, version roller will ink to scraper, printing ink of scraper a force in the role of the spatula to turn the by the trend of the cylinder, to overcome this trend, and there is a pressure version roller, forcing version roller nets pit of the ink scrape, if the rigid, in order to poor scraper scrape nets pit of the ink, will increase the pressure in the cylinder, so as to increase the squeegee pressure to version roller, such, scraper slice and version roller easy wear away, do a lot of waste. Of course the best working state is using minimum squeegee pressure scrape version roller nets pit of the ink, such already save scraper piece, version roller and not easy to wear. The adjustment of the squeegee pressure generally in 0.2 ~ 0.3 Mpa.


　　3. The sword scraping ink installation accuracy of institutions is to influence the quality of printing a major factor, scraping ink knife agency installation, must ensure that sword scraping ink floor level, if scraping the bottom level of the sword ink poor precision, it will make floor height not consistent about scraper, cause scraper or so height not consistent, such result is the sword scraping ink about pressure does not agree, and influence printing quality. In the printing process, if found or so, will find two-tone color ink scraping knife floor level precision whether meet the requirements.


    4. The sword scraping ink splint on plywood and plywood under the processing precision also influence printing quality ink scraping the sword, if under the plywood and plywood flatness is very poor, so, when the plywood and plywood under scraper slice and scraper pad will be installed in together, the flatness of scraper can be affected, become the microscopic of the wave of, in order to eliminate this on microscopic waves state, will version roller nets hole, the printing ink of scraper, will increase the squeegee pressure, causing the scraper slice and version roller wear.


　　Sword scraping ink scraping knife blade installation and ink Angle adjustment is also an important factor of influence printing quality, scraping ink when installation, is will scraper blade of scraper pad and installed in the plywood and plywood under the spatula between, adjust good install length with screws up, will the tight, so flush will scraper pad and of clamping la, scraper scraper installation is very exquisite, installed too outstanding, scraper scraper yi deformation, wavy, in the printing, some local can cleanly, some local blow not clean, thus affecting the printing quality; Scraper outstretched too short, and the lack of flexibility, so must increase squeegee pressure can pit, the printing ink of the net scrape, so easy to wear version roller. Scraper pad usually 20 to 30 mm out plywood, scraper out of scraper pad 5 ~ 7 mm. As shown in figure 2 shows for scraping ink blade splint device. Among them the thickness of the sword scraping ink pad for 0.3 0.5 mm general, add scraper pad the purpose is to strengthen the stiffness of scraper, scraper generally USES the thickness 0.1 0.15 mm high quality pieces of steel.


　　5. The sword scraping ink Angle adjustment is also very important, its view is to point to scrape the dao and ink version roller the contact Angle is alpha (blade and version roller contact points of tangent Angle between the size of the) (see chart 3). Contact Angle, the greater the scraping ink alpha effect more, but blade easy to wear, the contact Angle is too small, and makes the scraping ink alpha version roller dao and the contact area, scraping ink increase effect is poor, easy generation version of the mist, wear easily. Generally, the contact Angle 45 ° 65 alpha take ° advisable, Angle according to the size of the printing material, and use of the ink and printing speed to determine.


　　6. Scraping ink knife pressure adjustment to printing quality is a key factor. Sword scraping ink scraping ink to pressure is done by the sword version roller drum pressure, scraping ink knife the key role of the pressure have two: the first is will the graphic area outside the pit is nets scraper ink; The second is the impact of the ink, stop resisting the ink flow from the blade. Squeegee pressure is too small, easy to let the graphic area produce edition fog or cutter line, when the printing speed up, version roller speed increases, version roller with the linear speed increases, the ink scraping ink printing on the impact of the sword, and that increases to scrape up the sword, the serious influence ink printing quality. Squeegee pressure is too big, can reduce the transfer of ink rates version roller and scraper piece of wear are high. The size of the sword scraping ink pressure by its role is to decide, namely: P = P1 + P2


　　P for scraping ink needed for the sword pressure


　　Will the graphic area for P1 both nets hole of ink scrape the clean pressure


　　To resist the impact of the ink P2 required pressure


　　And resist the pressure of the impact of the ink needed with squeegee pressure P2 horn, ink on the linear V. Namely: P2 ∝ COS alpha V2


　　From this Angle, the greater the squeegee pressure P2 is smaller, scraping the ink needed for the sword; and the more small pressure P The smaller the printing speed of the ink, the smaller the linear V also, the smaller the P2, scraping ink needed for the sword; and the more small pressure P Conversely, the smaller the squeegee pressure Angle, the greater the P2, scraping the sword of the pressure for ink the P; The printing speed, the greater the ink is bigger also, P2 linear V, the greater the pressure of the sword scraping ink for the P.


　　In actual work, according to the method of scraping ink above adjust knife, that can assure the corresponding printing quality. Printing machine in the use of a long time, because DuoZhong wear of the factors that could make relevant important components precision drops, also can produce the same printing quality problem. This is a need for further analysis and judgment. Thus promptly eliminate scraping ink on the influence on the quality of printing sword, reduce scrap, increase yield, improve the production efficiency.