Rubber Coating Roller Conveyor Roller for Paper or Textile Industry

A rubber roller is a machine part composed of an inner round shaft or tube covered by an outer layer of elastomer compounds. The inner shaft is made of steel, aluminum alloys, or other strong and rigid material composites. On the other hand, the outer layer is typically fabricated from a polymer such as polyurethane, silicone, EPDM, neoprene, and natural rubber.

Neoprene (Polychloroprene): This synthetic rubber offers excellent water, oil, and heat resistance, and it's ideal for coating, laminating, paper, and textile manufacturing, as well as offset, web, and flexo printing. It's latex-free and available in various densities, so you can find the appropriate balance of support and cushion. However, it's important to note that neoprene doesn't do well in low-temperature applications, and it is more expensive than some other elastomer options.

Neoprene + PVC: Dense and durable with excellent chemical resistance, PVC rubber rollers are reliable, cost-effective, and resistant to corrosion. PVC adds additional wear resistance to neoprene.

Silicone: Commonly used for high temperature applications with high release properties (limiting the amount of materials that stick to it), silicone rollers offer good resistance to moisture, light, and ozone. They're commonly used in hot stamp, heat transfer and heat seal applications, laminating, film, medical imaging, mail sorting, cleaning, and extrusion rubber roller applications. Compared to other materials, silicone may have lower mechanical properties.

RTV Silicone: RTV silicone is water repellent and available in soft to medium hardnesses, making it suitable for printing and photocopying applications. Though more expensive than regular silicone, it's exceptionally stable and holds up well under challenging or harsh conditions.

Polyurethane/Urethane: Tough and versatile, polyurethane is a go-to choice for nearly any rubber roller application, including paper making, embossing, laminating, converting, and harsh mechanical environments like steel mills. It offers high shock absorption, fatigue resistance, impingement resistance, load-bearing, and rebound.

Hypalon: Ideal for coating, laminating, embossing, and extrusion rubber roller applications, Hypalon offers UV, abrasion, chemical, and flame resistance. It's waterproof and maintains its integrity in extreme temperatures, and features a tensile strength of up to 3,000 psi.

Ethylene Propylene (EPDM): Chosen for its chemical, heat, UV light, and ozone resistance, EPDM rubber rollers are common in the printing industry. This versatile material offers good weathering resistance as well as superior insulating and dielectric properties while maintaining its mechanical properties in a wide range of temperatures.

Standard rubber roller manufacturing involves a rubber fabrication step, which can be achieved either by plying method, extrusion, casting, or die press.
Plying involves the calendering process, during which, to make calendered rubber sheeting, rubber is passed through a combination of rollers. As the rubber sheet moves through the rollers, it is smoothed and flattened. Using this process, two types of polymer can be sandwiched together, if an application demands. Once the calendered sheet is ready, the sheet becomes a rubber cover of an iron core or another metal core. With that, it is a rubber roller. Based on client requirements, sheets can be polished, glazed or embossed.
Extrusion is the most common manufacturing method that involves an extruder. With this method, a rubber profile of fixed cross-sectional can be made continuously by-passing rubber through a die. In this process, raw material is heated by passing it through a screw mechanism, which heats material by a combined action of pressure and temperature, and then the material is pushed through the die. The critical step in this fabricating technique is curing, which involves conditioning the rubber product in a controlled environment where it is exposed predetermined temperature and pressure. The curing process gives the structural strength to a rubber product by removing porosity.
Casting, inarguably, is the oldest way of giving shape to a range of materials. From automobile engines to high-end sculptures, have been crafted by this method. Whatever the material is, all is molded by the same principle, which involves pouring of raw material in a mold and then exposing it to an oven for a period of time that cures it and sets it in a predefined shape.
Die press rubber fabrication commonly involves a hydraulic press and a die. The die gives the shape to the raw rubber, whereas press provides pressure and heat to cure the rubber product. The process begins by filling raw rubber into a metal mold, and then a hydraulic arm fitted with a die presses the mold and provides heat and pressure. Unlike extrusion, the press method is not continuous, thus is not as efficient as extrusion.

Roller Manufacturing
Rubber rollers are usually manufactured via casting or molding, but they may also be made through extrusion.
Casting processes are utilized only with rubber rollers that have metallic cores. In this case, cores are formed through a metal casting process like stamping, after which they are bound to a rubber coating. Binding is carried out using a bonding agent that is usually made of polymer-solvent solutions, a primer coat based on phenolic-style resins and a top layer of mixed polymers and other various materials.
Rubber roller molding processes include compression molding and injection molding; these are used for solid rollers.
Extrusion of rubber rollers takes place when manufacturers heat chosen elastomeric material(s) and squeeze the molten material through a die that has a pin in the center to fabricate the hollow tube.

Grooving
The next step involves surface grooving. There are a number of grooves that can be created on a surface of rubber, including square, trapezoidal, "V" , double edge saw, half circle, and round. Moreover, on a rubber roll, these grooves can be made vertically, horizontally, helically, worm, diamond cut groove and screw threaded.

Inspection
At the end of this step, the products are inspected for aberration.

Materials
The elastomeric materials from which manufacturers can choose from are fairly varied. Each material has its own strengths and weaknesses, but all of them have some level of resistance to water, wear, certain chemicals and heat extremes.
Among the many, a few materials that are frequently used to fabricate rubber rollers include: EPDM, silicone, nitrile, neoprene, polyurethane and natural rubber. Metal core rollers are usually made with steel, stainless steel, aluminum or another metal that fits application requirements.

Laminating Machines
These rollers must be made of a heat-resistant material, like silicone, for large or small lamination projects.

Paper Industry
For processes like drying, sizing, and calendaring, the paper industry uses various rubber rollers made of materials like EPDM, styrene-butadiene (SBR), neoprene, polyurethane, and natural rubber that meet specific needs for hardness, temperature resistance, and abrasion resistance.

Plastics, Steel Manufacturing, and Roofing Materials Manufacturing Industries
Conveyor, drive, and grooved rollers are common in all sorts of manufacturing processes. Rollers are also used for grinding, sanding, and more.

Textile Mills
Spreader rollers are used in the textile industry, as well as the paper industry, to remove wrinkles.

Wood Industry
Polyurethane is a common choice for rollers in the wood industry because it's flexible, durable, and resistant to low temperatures, oils, solvents, water, and impact. It also offers excellent shock absorption. Rollers in this industry are used for conveying, sanding, grinding, and more.

Printing
Rubber rollers are used for texture and pattern painting and specialized cleaning applications.