|% Incline||Multiply by:|
To calculate the rolling capacity of a winch – the amount of load that can be pulled up an incline – multiply the winch capacity by the factor shown in the chart. The multiplication factor shown includes a 10% rolling friction factor. Note: 5% incline is a 0.5 m rise in 10 m.
For boat trailers commonly used ratio of boat size to winch is 2 to 1. But there are many factors to consider in selecting the proper winch size. It is sometimes difficult to determine the amount of load being pulled with a winch. All D-L hand winches are designed to pull their rated capacity with a force on the handle in the approximate range of 35 to 55 pounds. This means that the winch should be able to be cranked easily with one hand. If not, it is probably overloaded.
Because the high forces generated when using a winch create potential safety hazards, careful consideration should be given to the winch selection process.
Safety should be a primary concern and questions such as what winch features are required for the application, what will be the experience level of the user, and what what harsh enviromental conditions will exist, should all be answered. More specifically, an important first question should be “Does the application require the freewheel feature (the ability to pull cable freely from the drum to attach the load) available in ratchet-type pulling winches?” If not, a self-locking type winch (brake winch or worm gear winch) should be used. Generally, ratchet-type pulling winches are not recommended for lifting applications, and their use is discouraged in other than horizontal or incline pulling operations requiring a freewheeling feature.
D-L winches are not designed to be used as hoists for lifting, supporting, or transporting people, or for loads over areas where people could be present. D-L winches are built to high quality standards, but do not include the features necessary to make them appropriate for moving humans or overhead hoisting and lifting applications.
All D-L manuel, brake and worm gear winches are CE-marked 89/392/EEC.