Applications for Flexible Wire and Cable

Flexible wire can be used for a wide variety of applications in a wide variety of industries. Medical device, aerospace and automation manufacturers often require flexible cables for several of their products. Sometimes a simple description such as, “the wire needs to be as limp as a wet noodle” is enough to understand your needs.  The choice of type of conductor and insulation can greatly influence the flexibility of the cable performance. Understanding what the flexibility requirements are will help to determine the materials and construction for the flexibility of the wire or cable.

When specifying a flexible cable you need tell your cable manufacturer what the intended use will be.  Being as specific as possible when it comes to the requirements of the application will help the engineers design the cable to meet these specifications.

• Do you need to route it through equipment or a tight space?
• Will it be subject to continuous flexing?
• Do you need the cable to flexible during use?

There are several characteristics of flexible wire that make it unique, such as:

• Conductor stranding
• Shield types
• Cable lay 
• Insulation materials. 

In conductor stranding, the more strands a conductor has the more flexible the cable will be.  “Off the shelf” wire and cable is stranded in 7 or 19 strand configurations, which is not flexible enough for most applications requiring flexible or high flex cycles. The general rule is the higher the strand count of the conductor, the more flexible the wire is. Stranded conductors are composed of un-insulated “strands” of wire twisted together. The advantages of stranded conductor over a single strand are increased flexibility and flex-fatigue life. When you see 22AWG (19/34) for example, what the description means is that there are 19 strands of 34 AWG making up the 22 AWG conductor. Other common options for a 22 AWG is a single strand (solid) up to 168/44 strands. The construction of the conductor also plays a role in the cable’s flexibility, for example a rope stranding is the most flexible.  For repetitive flexing applications, the use of high strand alloy material is recommended.
Choosing the right insulation can also add to the cable’s flexibility. Silicone is one the most flexible of the compounds used in wire and cable.  Silicone wire is used to meet a variety of demands such as extreme high and low temperature requirements, flame resistance, flexibility, strength and purity. The application of the cable and the environment that it will be exposed to also plays a role when choosing the right jacket material. Harsh environments, chemicals, and abrasion will narrow down your insulation and jacket options.  Discussing your flexible wire application with an experienced cable manufacturer can help you choose the right materials for the performance and longevity of your product.
To learn more about the applications of flexible wire and other custom cable solutions, please visit: http://www.calmont.com/robotics.php