What to Do When Oil-Resistant Conveyor Belts "Swell"? Cause Investigation and Prevention Measures
When oil-resistant conveyor belts show signs of swelling—such as increased thickness, reduced hardness, or even surface blistering—it directly affects their load-bearing capacity and service life, and may even lead to sudden belt breakage during operation. Therefore, quickly identifying the causes of swelling and taking targeted measures is crucial to restore the normal operation of the conveying system.
To investigate the causes of swelling, the first step is to check the type of oil in contact with the belt. Not all "oil-resistant" belts are resistant to all oils—different oil types have varying chemical properties. For example, some belts designed to resist mineral oil may swell severely when in contact with vegetable oil or synthetic oil, because the oil molecules penetrate the belt’s rubber matrix and react with the polymer material. You need to compare the belt’s product specification sheet with the actual oil used in the site to confirm whether there is a mismatch between the belt’s oil resistance range and the oil type.
Next, pay attention to the temperature of the oil and the operating environment. High temperatures will accelerate the penetration of oil into the belt and intensify the chemical reaction between the oil and the rubber. Even if the belt is compatible with a certain type of oil at room temperature, prolonged exposure to high-temperature oil (such as oil heated above 60°C) can still cause swelling. You should measure the actual temperature of the conveyed oil and the ambient temperature of the conveyor line, and check whether it exceeds the maximum temperature limit specified by the belt manufacturer.
Another key factor is the contact time and frequency. If the conveyor belt is in continuous contact with oil for a long time—for example, the belt surface is not cleaned in time after conveying oil-containing materials, or oil leaks from the equipment and accumulates on the belt—the oil will continuously infiltrate the interior of the belt, leading to gradual swelling. You should check whether there is oil leakage in the conveyor system (such as from bearings or oil pipes) and whether the post-conveying cleaning process of the belt is in place.
After identifying the cause of swelling, corresponding prevention measures can be taken. If the problem is an oil type mismatch, replace the belt with a model that matches the actual oil type—for example, choose belts with nitrile rubber (NBR) as the base material for mineral oil resistance, or fluororubber belts for strong corrosive oils. For high-temperature oil scenarios, select oil-resistant belts with high-temperature resistance (such as those marked with "high-temperature oil-resistant" on the specification sheet) and add heat insulation devices to the conveyor line if necessary to reduce the belt’s direct contact with high-temperature oil.
To reduce the impact of prolonged oil contact, establish a regular inspection and cleaning system. Arrange for daily checks to see if there is oil leakage in the equipment, and promptly clean up oil stains on the belt surface using a professional oil-resistant cleaning agent (avoid using solvents that may damage the belt). At the same time, set a reasonable replacement cycle for the oil-resistant belt—even if no obvious swelling is found, replace the belt regularly according to the manufacturer’s recommendations and the actual frequency of oil contact to prevent hidden swelling risks.
In addition, optimizing the conveyor line design can also help prevent swelling. For example, install oil-retaining plates or guide grooves at the parts where the belt is most likely to come into contact with oil to reduce direct oil splashing onto the belt. If the conveyed material contains a large amount of oil, add a pre-deoiling process before the material enters the conveyor belt to reduce the oil content adhering to the belt surface.
By systematically investigating the causes of swelling and implementing these prevention measures, you can effectively reduce the occurrence of oil-resistant conveyor belt swelling, extend the belt’s service life, and ensure the stable and safe operation of the entire conveying system.
