A come-along is a hand operated ratchet lever winch. A winch is a mechanical device used to wind a rope or cable, while a ratchet is a mechanical brake that keeps the line from unwinding. Come-alongs are convenient and portable enough to use in almost any situation, because they are small enough to carry in one hand and weigh an average of only 10 pounds (about 4.54 kilograms).
These tools are used for pulling joints together, for straightening heavy panels while putting them in place, as safety ties, and for pulling the frame of a new construction together during its raising. They can also be used for stretching, lifting, and lowering objects. In addition to construction and industrial applications, a come-along is useful for towing boats, cars, and gliders. On boats and ships, it can be used to pull anchor or mooring lines, sheets, and halyards.
A come-along can be purchased in a variety of sizes and weight lifting capacities for varying construction needs. Lifting capacity generally ranges from 1 to 3 tons (907.19 to 2721.6 kilograms), with a 6 to 12 foot (about 1.83 to 3.66 meters) lift height. It is important to adhere to the recommended weight limits provided with the tool, as it is susceptible to fatigue fractures if repeatedly operated at even a small percentage of its tensile breaking strength.
Many come-alongs are designed with internal clutches in order to limit operating loads. Within these limits, however, the wire rope can rust from the inside out. In addition, the cross sections of chain links are reduced through wear. Frequent lubrication will extend the life of the device.
A come-along can also be equipped with a web strap to prevent twisting, as well as a safety feature called a breakable stress link. If it is overloaded, the stress link breaks. This lets the operator know to back off the load before the fiberglass handle snaps, preventing both personal injury and equipment damage. The stress link can be easily replaced if damaged. Replacing the stress link is far less costly and difficult than if further damage were to occur to the equipment due to excessive stress.