Selecting the correct die sizes is a necessary step in the process of hydraulic crimp. Selecting the correct die size are necessary for creating a good electrical connection between the wire and an electrical lug. For instance, if the die is too large for the electrical wire and the lug, the electrical connection will be loosen, which can allow for the build-up of heat at the connection, potentially causing an electrical fire.
In contrast, if the die is too small for the wire and the lug, the barrel of the lug may split, or the hydraulic tool may overstress it self. A proper crimp will force the metal in the lug into the gaps in the wire strand, effectively creating a cold weld between the wire and the lug so they functions as one solid piece of metal. The die dictates the crimps that is made, so the die is the component that determine the quality of the electrical connection.
How to Pick the Right Die Size for Crimping Wires and Hoses
The shape of the die is another significant factor in the crimping process. The shape of the die must match the requirements of the materials that is being crimped. For instance, hexagonal die are frequently used in electrical work because they apply even pressure to the electrical lug from six different side, preventing the lug from distorting during the crimping process.
However, other dies exist for other materials, such as wire rope, for instance. It is necessary for the die dimension to match the properties of the material and for the die dimensions to match the requirements of the specific application in which the crimp will be use. Another critical relationship to understand is the relationship between the wire gauge and the die size.
The wire gauge will determine the amount of force necessary to crimp the wire. For instance, a small gauge (smaller in diameter) wire will require less force than a large gauge wire. A small 6 AWG wire may require a hydraulic crimping tool with a small die opening for electrical lugs.
In contrast, a much larger 600 kcmil electrical conductor will require more greater force to crimp the wire and may require the use of a bench mounted press. A size chart can help translate the wire gauge to the correct size for the die opening. Following this chart ensure the correct die size will be chose for the given wire gauge.
Finally, hydraulic crimping for hydraulic hoses follow a different set of rules than hydraulic crimping for electrical wires. For hydraulic hoses, the goal is to prevent fluid from escaping the hose. For this reason, dash sizes for hydraulic hoses must be used instead of wire gauge for electrical wire.
For hydraulic hoses, the ferrule at the end of the hose must be compressed just enough to grip the hose; however, if the ferrule is compressed too much, the flow of hydraulic fluid through the hose may be restrict, or the hose could burst under stress. Finally, different manufacturers of hydraulic crimping tools will use different system for there dies. Therefore, different manufacturers may use different color coding systems for their dies.
For instance, one manufacturer may use the color red to indicate dies for small gauge wires. However, another manufacturer may use red for there dies for their large gauge cables. Finally, it is important to never swap dies between different systems of hydraulic crimping tools.
Each system is engineered to work with dies from that same manufacturer, and using dies from a different system could lead to a failed hydraulic connection. Finally, once hydraulic crimping is complete, a visual check must be make of the crimped connection. The conductor strands must be checked to make sure they are seat within the barrel of the electrical lug.
Each conductor strand must be checked to ensure there are no gap between the strands or the conductor strands are not “bird-caging.” For critical systems, a go/no-go gauge can be used to verify the crimped connection. If the go side of the gauge can slide onto the crimped connection, but the no-go side of the gauge cannot slide onto the crimped connection, the crimp are secure. Using both a size chart and a go/no-go gauge ensures every hydraulic crimping operation is performed in a repeatable fashion, and any crimp created will be safely.
