Draper Heavy Duty Castor Trolley Wheels Polyurethane 50mm - 200mm, 50kg - 500kg Castors - working out your load To calculate the safe working load for each castor take the weight of load in kilograms and divide by the number of castors minus one eg 100kg divide by 3 (4 wheels minus 1) = 33kg. So each castor would need to be rated at a maximum safe working load of 33kg. Nylon versus Polyurethane When making the choice between nylon and polyurethane the usage has to be considered. Polyurethane is for heavy duty applications where a lot of weight is being carried. Nylon will not mark and is generally used for lighter domestic-type applications. Polyurethane Wheeled Swivel Bolt Castor - 12mm diameter swivel bolt fixing. High tear strength, up to twice the service life of rubber wheels.
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