What Happens To The Press Rubber Roller During Operation?

With the continuous development and needs of the pressing technology, the pressing department widely uses hard synthetic Dongguan rubber rollers. It not only has high hardness, but also has good dehydration effect under high linear pressure. However, such covered rolls still have some problems in high-speed paper machine making, such as high early wear on the roll surface, and easy peeling between the roll body and the rubber layer.

Under the conditions of high speed of the paper machine and high line pressure of the nip, the hard synthetic rubber is prone to mechanical wear, damage and abrasion; Compression heat is generated, and it is not easy to release. Deterioration of the material caused by heat generation, or even burnout, can cause problems with the rubber roller.

The following briefly introduces several common damage phenomena of rubber rollers in Dongguan and their countermeasures.
Chemical attack

After the coating material on the surface of the rubber roller absorbs or (and) reacts with a chemical substance, it changes the mechanical properties of the roller surface system, such as hardness and abrasion resistance.

In general, chemical damage is not easily detected. After long-term chemical erosion, the wear of the roller surface is accelerated, thereby making the holes into a cup shape. With the expansion of the cup shape, the space roller surface forms a ridge shape, which seriously affects the quality of the paper.

Drilling and groove pattern Dongguan rubber roller surface will have a larger exposed area in the chemical substance of the pulp liquid, especially for the roller surface drilled with through holes, the adhesive layer between the rubber surface and the roller core will directly contact the chemical substance. If these roller surfaces with through holes, blind holes and grooves are exposed to chemicals for a long time, the roller surfaces will usually be deformed.

After chemical erosion, the hardness of the roll surface changes significantly. Generally soften, but occasionally it will harden, and some rubber surfaces even swell. Another consequence that may occur after chemical attack is that the rubber surface feels "sticky".

If the roller surface of the blind hole pressing roller is regularly ground and the blind hole is kept at a sufficient depth (not less than half of the depth at the factory) and clean and stain-free, it will have high dewatering efficiency. Insufficient grinding usually causes the rubber surface to be damaged. However, if the blind hole is blocked by residues and continues to run, it will cause the effective diameter and effective depth of the blind hole to decrease, which will reduce the dehydration ability and dry the wet paper. In addition to the obvious decrease in the degree, it will also damage the rubber surface.


The material blocked in the hole becomes a cylinder. When the roller surface passes through the nip, the solid surface in the hole is squeezed and the cover surface is seriously affected. Due to the abnormal stretching, expansion, and heat generation of the blind holes in the nip, the deformation is intensified, and the intensification of the deformation and expansion further increases the heat generation when passing through the nip here, eventually causing cracks between the holes.

1.Roller surface damage caused by external spray of vacuum roller

If the cleaning and spraying device outside the vacuum roller is not used properly, the rubber surface will be damaged. These high-pressure water needle nozzles usually swing and spray along the roller surface at a distance of 7.62 to 30.48 cm. These damaged rubber surfaces may be due to excessive nozzle pressure, improper nozzle alignment, or both. Sometimes, even if the spray installation is used correctly and the rubber surface has been chemically corroded, this damage can also occur. By observing the damage pattern of this roller surface, it is found that the rubber surface damage caused by this spraying has its significant characteristics. One is that the damaged part starts from the same side of the hole, and the other is that the damaged part is spiral.

Dongguan rubber roller | Generally, as long as the fiber and residue on the roller surface can be cleaned, such water pressure is sufficient. Excessive water pressure will cause the rubber surface to wear. In addition, if the covering surfaces of the nozzles overlap and overlap, the spray strength at the overlap will increase, and the wear will be severe. Proper nozzle placement is also very important. The optimal cleaning nozzle angle should be 90 ° with the tangent to the x axis of the roller. If the angle of the nozzle is adjusted and the nozzle pressure is increased due to chemical corrosion of the rubber surface, the speed of the rubber surface damage can only be accelerated.

2.Vertical wrinkle of roller surface

Longitudinal (direction across the paper machine) wrinkles, also known as striped wrinkles, are caused by vibration or shock, and vibration and shock are caused by a variety of reasons, which mainly include the following factors: eccentricity, such as roller surface or Eccentric body, eccentric assembly of bearing and ends of both ends; impact or roll surface peeling, roll surface being cut or excessively squeezed, including scratches by scraper device; poor balance of roll body; excessive cooling water in water-cooled roll body ; The frame is not strong enough or there are missing parts.

When the roller body runs on the paper machine, although the wrinkle phenomenon only occurs on the surface, the fact that the surface is arranged on the surface means that the inside of the roller surface material is severely squeezed. Once the roll surface is wrinkled, the roll body will bounce rhythmically and produce ribs with a certain interval. Occasionally, such slivers appear at the location where the vibrations occur. Closing the nip and applying pressure for a while can be regarded as a way to eliminate the occurrence of streaks.

3. Impact damage of Dongguan rubber roller surface

Impact damage is caused by incompressible or hardly compressible materials entering the nip, which compresses the roller surface violently. The result is an instantaneous overload and local pressure, resulting in extremely high pressure, heat and stress. Typical examples are folded paper sheets, slugs, hard devices, etc. that enter the loading nip, which cause the covering material to chip, degumme, and even peel off from the roller core. Usually the damage appears to have only slight dents and embossing on the roller surface, but any cracks and damage on the roller surface must be carefully and comprehensively checked to confirm that the primer is intact.

If impact damage has occurred, then the inside of the working rubber surface material has been damaged, and the covering surface can no longer be used. It is recommended to grind the damaged part on the grinder and then grind it at least 1.6mm. If the damage has reached the primer layer on the roll surface, the roll surface must be renewed.

4.Severe or long-term overload operation of Dongguan rubber roller surface

Frequent local severe overload can cause serious damage to the roller surface. Although the situation is different, similar damage will be caused by inappropriate high-to-medium amount, no chamfering or insufficient chamfering at both ends of the covering, and control failure of the controllable medium-high roller.

A certain medium-high amount of the roller surface is only applicable to a certain pressure load value (only this one pressure value). If in a given nip, increase the compressive load without changing the middle and high amount, the overload at both ends will cause damage; similarly, if the compressive load decreases and the middle and high amount does not change, the middle of the roller surface will be overloaded. In short, it is necessary to distribute the load as evenly as possible to all parts of the nip.