Engineers Guide to Castor and Wheel Selection Selecting the correct Castor Wheel for your application will ensure best performance and longevity are achieved. The decision you make should be based on various factors, such as Maximum Load, Floor Type and Environmental Factors........... This guide provides some of the basic considerations when selecting a Castor Wheel
Load Capacity One of the most important Factors when selecting a castor type is the Weight (load) in which you will apply to each individual castor. Designers should consider Weight Distribution, Shock Loads, and Flooring Types when making this calculation. If a piece of equipment, such as a Trolley, requires 4 Castors, the Designer should firstly calculate the total weight of the equipment including any Payload. The next step is to determine the weight distribution. In this instance, we will assume that all castors are equally loaded. The next step, which is commonly overlooked, is the effect that flooring type has on the weight per castor. In this instance we shall assume that the castor is being used outdoors on a concrete floor. Due to the unevenness of the floor, it is probable that at times only 3 of the 4 castors will be touching the floor, resulting in the load being spread over 3 castors only.
A common formula for calculating the maximum possible Load on a Castor is as follows:
EQUIPMENT WEIGHT + MAX. PAYLOAD + SHOCK FORCE / 3 = MAX WEIGHT PER CASTOR Note: Shock Force should be calculated by a competent engineer. Customers should contact their Castor supplier. As an example, shock force from a Kerb drop is approx. 15-20% of Equipment plus Payload
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