Pubdate：05-06-2022 Views：4123
Moisture, sunlight, ozone, chemicals, heat, cold and petroleum products all have an influence on belt performance and life.
Moisture has long been an enemy of conveyor belting, especially those made with cotton and rayon carcasses. When attacked by moisture they rot, weaken and lose adhesion. Early detection and repair of cover damage will help prevent these conditions. Nylon and polyester carcasses are unaffected by moisture, but regular cover inspection and repairs are necessary to prevent abrasive particles from entering cuts and grinding on carcass fabrics.
Belts with steel cable reinforcement are also subject to deterioration from moisture if they are exposed due to cover damage. The cords may corrode which will lead to tensile strength loss and low adhesion. Surface moisture can also be a problem. Material can cake on conveyor pulleys, idlers and belt surfaces to cause tracking problems. Moisture can also cause slippage. Material caking can be removed by installing belt wipers near the drive pulley.
The effects of sunlight are especially severe in hot, dry climates and at high altitudes. The conveyor belt rubber, especially under tension, will dry out and crack. Because cracking can be expected under these conditions, any sort of protection will be beneficial. Leave belts in their protective packages while in storage. SKE rubber covers are compounded to minimize the degradation that results from sunlight exposure.
Regular exposure to ozone will cause rubber to crack and lose its tensile properties. Ozone is produced by ultra-violet rays from the sun, electric arc welders and electrical generating equipment. Although there may be no protection from sun-produced ozone, covering belts that are near electrical ozone producers will minimize industrial ozone effects. SKE uses ozone inhibitors in their rubber compounds for above ground applications.
Storage of belts at temperatures over 90° F for long periods of time can dry out and weaken covers. In carrying hot materials, the effect is the same. If a hot load is carried in a closed area, the effects are more severe than in an open one. Where heat is a problem SKE offers you a variety of heat resistant carcasses and cover compounds.
Although low temperatures rarely have a harmful effect on rubber compounds, the stiffening of the belt may cause training problems until it warms up. This is especially true of belts containing neoprene compounds. Before these belts will train properly, they must be warmed to a temperature above freezing.Frost, snow and ice can also affect belt performance: On an incline surface a layer of frost can cause load slippage Ice can build up on conveyor hardware and cause more damage than material buildup Ice can form on the troughed side of the belt and plug chutes
The preferred method for removing coldweather glazing is ethylene glycol. Calcium chloride solutions are also sometime used, but they can corrode conveyor parts. Ice buildup should be removed before the conveyor is started. If the system must be kept ice-free at all times, the gallery should be covered and heated if possible. The general effects of cold on conveyor systems are: increased power demands during startup, freezing up of rotating mechanical parts and causing drive motors to stall. A wise course when running a conveyor in extremely cold conditions is to never shut the conveyor down. This can be done by either running the belt at full speed or by using a creeper drive on the system.
When rubber is attacked by oil or grease it swells and loses tensile strength, abrasion resistance and adhesions. Belts will wear rapidly or curl in reverse. SKE offers a complete line of oil service conveyor belts, compounded to specific oil resistance needs.
Certain chemicals can affect rubber compounds. The attack on the compound can cause blistering, cracking and total deterioration. SKE manufactures a wide variety of chemical resistant belt styles. Please consult with a FDA representative for a proper recommendation.
