Microwave/Infrared Rubber Vulcanization Line

It is used for efficient processing, heating, drying or material transformation.

High efficiency, process reliability and complete customization.

Yes, Kerone offers fully customized engineering solutions.

Food, chemical, pharma, biomass, rubber, textile and more.

Kerone ensures high product quality through strict engineering standards, advanced testing procedures, and precision-controlled manufacturing systems.

EPDM, silicone, SBR, NBR, HNBR, CR, and most standard extruded rubber compounds can be vulcanized on Kerone's microwave/infrared lines.

Microwave/infrared vulcanization eliminates the need for hazardous salt handling, provides superior heating uniformity, requires no post-processing washing, and is more energy efficient.

Product samples are tested for hardness, compression set, tensile properties, and cross-link density following standard rubber test methods (ISO, ASTM).

Microwave energy heats rubber volumetrically from the core outward, which is ideal for curing the bulk of an extruded profile, but it does not always deliver an optimal surface finish on its own. Infrared heating, positioned between the extruder and the main vulcanization tunnel, pre-cures the outer skin of the rubber profile quickly, improving dimensional stability and surface quality before the part enters the microwave section. The combination addresses the limitation of each technology used alone: infrared alone struggles with thick sections because rubber is a poor thermal conductor, while microwave alone can leave surface finish less refined than infrared pre-curing achieves. Running both in sequence produces a profile that is uniformly cured through its cross-section while maintaining the surface quality manufacturers expect from extruded rubber goods like hoses and seals.

Typical configurations handle throughput in the range of 50 to 500 kilograms per hour, with conveying speed adjustable between roughly 2 and 50 meters per minute depending on profile cross-section and cure requirements. Installed microwave power generally ranges from about 1.45 kW to 29 kW, scaled to match line speed and rubber compound. These figures vary significantly based on the cross-sectional area of the profile being cured, since thicker or denser profiles require longer residence time in the tunnel to achieve full cross-link density. Manufacturers should size their line based on the heaviest, slowest-curing profile in their product mix rather than an average across their full product range, since under-sizing for the most demanding product creates a bottleneck.

Cure quality is typically verified through standard rubber testing methods, including hardness measurement, compression set testing, tensile property evaluation, and cross-link density analysis, following recognized ISO or ASTM test protocols. Buyers evaluating a new line should request sample output from their own compound formulation rather than relying solely on generic reference material, since cure response varies by compound family and filler loading. It is also worth asking suppliers to demonstrate consistency across the full width or diameter of a profile, not just a single test point, since uneven cure across a cross-section is a common failure mode in continuous vulcanization that single-point testing can miss. A trial run with documented before-and-after test data gives the clearest picture of expected production quality.

Microwave and infrared vulcanization eliminate the hazardous handling, storage, and disposal concerns associated with molten salt baths, removes the need for post-cure washing to remove salt residue from finished profiles, and generally achieves more uniform heating throughout the cross-section. It is also more energy efficient since the system heats only the rubber and the immediate process zone rather than maintaining a large molten salt reservoir at temperature continuously. Salt bath systems may still be selected in operations already heavily invested in that infrastructure or for specific legacy product lines where switching technology would require extensive requalification. For most new installations or capacity expansions, however, the operational, safety, and environmental advantages of microwave/infrared systems make them the preferred choice.

EPDM, silicone, SBR, NBR, HNBR, and chloroprene rubber, along with most standard extruded rubber compounds, vulcanize effectively on microwave/infrared lines. The technology is particularly well suited to continuous profile products such as hoses, seals, gaskets, and weatherstripping where consistent cross-sectional cure and dimensional accuracy are critical. Compounds with very low polarity or minimal moisture content may require process adjustments or supplemental heating elements to achieve adequate energy coupling, which is why a compound-specific trial is recommended before full-scale commitment. Manufacturers running multiple compound types on the same line should expect to maintain a library of validated process parameters for each formulation rather than using a single universal setting.

Infrared pre-curing sections are typically compact, often around one meter in length, positioned directly after the extruder, while the microwave tunnel section is sized to match required residence time at the line's target speed. Compared to long salt bath tanks or extended hot-air curing tunnels that need significant linear floor space to achieve adequate dwell time, microwave-based curing tunnels are generally more compact for a given throughput because energy penetrates the material directly rather than relying on slow surface-to-core heat conduction. This compactness can be a meaningful advantage for manufacturers retrofitting curing technology into an existing building footprint where extending tunnel length is not feasible.

These lines incorporate integrated safety interlocks tied to a remote control panel, ensuring the microwave section cannot operate with access panels open or conveyor guarding removed. Step-less power control through a microcontroller module allows precise power adjustment rather than abrupt on/off switching, reducing the risk of power spikes. Digital displays provide real-time visibility into power and temperature parameters so operators can identify abnormal readings before they become safety issues. Microwave leakage containment is engineered into the tunnel design and verified against international electromagnetic safety standards, similar to the safety architecture used across Kerone's broader range of microwave processing equipment.