Anilox roller size tolerances

The dimensional tolerance is a key factor affecting the performance of the anilox roll

Most articles and technical articles on anilox rollers fall into the following four areas:
1. Engraving (geometry, number of screens, ratio of depth to open angle, etc.);
2. Laser (pulsed CO2, continuous band CO2 and YAG);
3. Coating of ceramic surfaces;
4. Clean, maintain and maintain.
These issues are all very important. They need to be thoroughly studied and understood before they can develop an ideal anilox roller system to ensure the stability of printing quality. However, in order for these important components to work properly, printers and anilox roller suppliers should also be concerned with other issues. This article is a brief introduction to some of the basic knowledge of the tolerances of the anilox roller size, including: bearings, bearing surfaces, gears, balance.

The tolerance of the anilox roller size is important because if the dimensional stability cannot be maintained, whatever the mesh geometry, the number of screen lines or the depth and opening of the engraving, and what kind of How can the laser sculpting, the quality of the anilox roller, or how good the anilox roller is cleaned, maintained, and maintained?

All components of the anilox roll, such as the diameter of the bearing surface, the diameter of the various stages of the gear, the keyway, the balance, the TIR (total indication deviation), the cylinder characteristics, the ring characteristics, the diameter of the surface to be sculpted, etc. must all fall on the Within the specified tolerance range, otherwise the anilox roller will not work properly. These problems are often overlooked by people, or do not fully understand the impact of tolerances on quality. Let's take a look at the issues related to space dimensions and tolerances.

A. Bearings and bearing surfaces The diameter of the bearing surface must meet the tolerances specified by the bearing manufacturer. Different bearing types and installation requirements, parameters have also changed accordingly. Different bearings have different internal diameters, outer diameters, tolerances, and rated loads. The deviation range of a bearing tolerance refers to the eccentricity of the bearing from its absolute center axis. There are many ways to describe this deviation, which we will explain later.
At present, many printers do not have the structural drawings of the printing press. They do not know the tolerance or allowable deviation of the outer diameter of the bearing surface of the anilox roller. Some people may not believe it, but it is a fact. The easiest way to understand these basic parameters is to turn to printer manufacturers. Another way to understand the size of the bearing surface is to find the bearing manufacturer's name. Usually the name is always engraved on the bearing base and written with the bearing number. After finding it, call the bearing supplier for specific parameter data. The following table shows the diameter tolerances of a certain brand of flange-mounted bearings and can be used as a reference.
Bearing sleeve tolerance
0.5" - 1.937", +0.0000" to -0.0005"
2" - 3", +0.0000" to -0.0010"
3.187 inch or more, +0.0000 inch to -0.0015 inch bearing bore tolerance
0.5" to 0.625", +0.0008" to -0.0000"
0.75" - 1.937", +0.0009" to -0.0000"
2" - 3", +0.0010" to -0.0000"
3-3.187 inches or more, +0.0012 inches to -0.0000 inches. Take the table above as an example. If a bearing with an inner diameter of 0.5 inches is used, the possible bearing surface tolerances (that is, bearing sleeve tolerances) are: 0.5 inches in maximum diameter, minimum The diameter is 0.4995 inches. The sleeves at both ends of the anilox roller are also often referred to as "pins".
Too small bearing surface size will cause the drum to rattle and inaccurate positioning, which will reduce the bearing life and damage the bearing surface. Poorly maintained bearings will harden during continuous operation, causing severe wear on the surface of the bearing sleeve. In severe cases, a new bearing sleeve needs to be replaced.
Maintenance personnel who unload old bearings or install new ones must ensure that the bearing surfaces and the bearings themselves are not excessively damaged. Frequent bush damages are marked by grooves, notches, grooves, or scratches on the surface of the drum caused by hammers, screwdrivers, sticks, and any other tools that may be used during the unloading of the bearings.
A basic principle is that you cannot hit the bearing on the shaft or under the shaft. Failure to properly handle the bearing during bearing installation will cause the sleeve to bend, causing the TIR (total indicated runout) to be too large, causing multiple printing problems and reducing bearing life. For the anilox roller, TIR refers to how the cylinder body (engraving area) works in conjunction with the bearing sleeve on the roller shaft. In general, the TIR of a bearing sleeve should not exceed 0.0005 inches.
It is best to invest in a better bearing removal tool (bearing pulled up) to unload the bearings and strictly follow the manufacturer's operational recommendations during the installation process. Before mounting the bearing, the bearing base can be inflated with the aid of a bearing heater, which is contracted to a perfect match between the bearing and the base. When installing the internal bearing, it is best to place the bearing in the cooler for one hour to allow the bearing to shrink to fit smoothly into the bore and seal it when the bearing returns to ambient temperature. In addition to this, it must be ensured that the bearing surface is free of spots or rough edges. It must also be ensured that the outer diameter of the bearing used in the bearing bore or bore assembly used in the outer diameter assembly is clean. A good suggestion is to apply a very thin film of oil on a less-smooth surface before installation. Smaller bearing surface radii or bevels in bearing bores also make the installation process easier. If the bearing is mounted incorrectly, the bearing can be damaged and the surface of the bearing or the surface of the bore hole offset. The result is that these surfaces are not concentric or incorrectly sized, and these conditions can affect future installations and cause TIR failures. Ultimately affect the printing quality and increase the additional cost of drum repair.
Typically in printing applications, "standard size" bearings are mounted on a running and sliding machine. Mounting bearings on such machines does not require pressure or other forms of force. This type of bearing is usually used for high-precision machines, gauges, high-friction machines and other operating machine parts.

Second, gear anilox roller on the gear handling, installation, removal rules and bearings the same. As with bearings, when the gears are installed incorrectly, they may cause the drum to bouncing, emit noise, or a coordinated change in the entire machine, which may damage the bushings, keyways, and gears.
When a keyway is damaged by a transition, it is better to roll out a new keyway on the original bushing, 180 degrees out of phase with the old keyway. In the process of rolling a new keyway, the most noteworthy area is the center of the keyway: it must be exactly in the center of the roller. Otherwise it will not be able to fix the key. To achieve a close fit, it is also important that the keyway has the proper length and width, as if a proper grinder were of the same importance to the correct shape of the keyway. Changing the width of the keyway requires the use of a more precise gauge rather than a snap gauge.
Another trouble with gear stepping is that people do not pay enough attention to stepping TIR. Any stepping of the anilox roller sleeve can cause many problems if there is a transitional deviation. If the gear bottom is at its lowest point or the surface of the gear is not uniform, the gear will jitter and buzz. In severe cases, this kind of jitter will also affect the transmission mode, which will seriously affect the quality of printed materials. This condition can also prematurely damage the gear.
From the numerous scratches and gouges on gear stepping or adjoining steps, one can see that people often mishandle them. Scratches and grooving are appearance damages that do not necessarily require extensive repairs. These deficiencies may only increase the difficulty of the move or installation process by simply clicking on the burrs or the replaced metal. The problem with the anilox roll suppliers is when these machines are damaged (perhaps only superficially) and influence the determination of the parameter change.
The TIR reading of a typical gear step is approximately 0.005 inches, and drum performance is not affected. However, this reading also varies with the press manufacturer's and gear tolerances. Some machine designs are very sensitive to roll deflection, so their OEM (original equipment manufacturer) has very stringent requirements for gear stepping. In this way, the deflection of the machine should be taken into account in the tolerances so that it does not affect the performance of the roller. During the initial and final stages of the entire process, all anilox roller suppliers should check all rollers for any bending or damage and record the inspection results. Especially in the initial inspection phase of the old drum, it is helpful to solve the problem by paying attention to whether the journal is bent or damaged. It is hoped that the damage and the subsequent repair cost can be reduced by modifying the operation and procedures.
In most cases, the person who orders the anilox roller is not the person who moves or installs the anilox roller, so it is necessary to communicate clearly and clearly between the parties. Bad communication can lead to reciprocal meetings, which is why it is so important to have good communication/recording between anilox suppliers and customers.
Third, the balance process according to the size of the printing press tolerances and the level of the printing quality requirements, anilox roller balance is a crucial factor. There are two kinds of balancing processes: static and dynamic. A similar example is the balance of car tires. The old bubble balance method is a static process, and the spinning balance method is a dynamic process.
An unbalanced roller can cause coordinated changes in the machine at different speeds, causing various problems on the press. Anilox roller suppliers must check the drum balance during the initial inspection phase of the anilox roller repair and report the results to the customer. During the manufacturing process of the roller, it is often found that there is a welded balance block (counterweight) inside the pipe. In some cases, the counterweights loosen and you can hear them rattle in the roller duct, which should give you enough vigilance.
At some point in the manufacturing process, the loosened counterweight may be absorbed by other debris in the drum pipe and become attenuated. This requires a better balance of technology to extract a large amount of material from the ends of the completed drum, to make the area empty to reduce the mass, or to insert iron bars as needed to increase the weight, and then position the solder joints in the correct position. If the original drum tube is far from equilibrium, it may be necessary to use an internally welded counterweight. Dynamic balance is generally used for a special roller RPM or FPM (surface size/minute)
Generally, narrow-width drums no longer require balancing adjustments, because they are mostly made of solid materials rather than metal pipes. The size, construction composition, and dynamic nature of the narrow-web presses differ from those of presses with large drums.
When fabricating new cylinders for any wide web or corrugating press, high quality tubular materials must be used to minimize the need for mechanical balancing.
More popular is the advanced "roller heat seal" tubular material, because even the strict parameters required for this material can ensure that the pipe wall thickness is uniform, thus reducing the need for excess balance.
As with many things in life, your efforts are directly proportional to the gains. Therefore, advanced pipeline materials are also accompanied by expensive prices. The gap between the prices of high-grade pipeline materials and low-grade pipeline materials is very obvious. Anilox roll suppliers have a parameter standard for evaluating all new anilox rolls for evaluating advanced piping materials.
To reduce downtime, save costs, and maintain high print quality, it is important to understand the spatial parameters of the anilox roll and how they affect the printing press, press performance, and the maintenance of the anilox roll.