There are several methods of connecting wiring together to both maintain electrical flow, and to provide a permanently connected wire joint, such as a pigtail. One of the most effective is a crimp sleeve, also known as a crimp sleeve connector. Crimp sleeves can be used to connect the same or different gauges, or diameters, of wire; they can be insulated or non-insulated, and they can be designated for various types of wiring, copper, aluminum, etc.
Basically, a crimp sleeve is a cylindrical metallic part, resembling a thimble that’s open at both ends. Bare, uninsulated wires of the same or varying gauges are inserted at the flared end, and crimped together. The crimping results in a fast connection that will not easily pull apart. If the wiring is for a pigtail, it is often twisted together, though many time this isn’t recommended.
The easiest way to crimp the sleeve is with a crimping tool. These tools resemble pliers, but are sized for the particular sleeve, and often contain wire stripping and wire cutting features. As a rule, crimping tools are considerably sturdier than ordinary pliers, and, since crimp sleeves are often large and difficult to compress, designed for maximum leverage.
Crimp sleeves are sometimes used to facilitate connection to a wiring terminal, and to ensure continuity of the electrical current. The material comprising a crimp sleeve is conductive, thus providing the necessary measure of continuity in the flow of electrical current. This boost is often necessary when connecting different gauges of wire.
Some types of crimp sleeves are insulated, in most cases using nylon or vinyl, to provide a measure of resistance to corrosion, moisture and heat. Very often, insulated crimp sleeves are used in outdoor applications, where environmental factors may be an issue. In many cases, crimp sleeve connectors are used to connect wiring in electrified fencing, such as that used to contain livestock. It may also be used to connect strands of unelectrified barbed wire. A crimp sleeve is designed as a permanent wiring connection, thus any alterations to the wiring will necessitate cutting the wire at the crimp sleeve.
Crimp sleeves are a bit different from butt connectors, end connectors, or bullet connectors, though each is a crimped connector. Generally, these latter connectors are not as durable as crimp sleeves, and do not require a dedicated crimping tool. A simple pair of pliers will effectively crimp these smaller, more delicate connectors.