Silicone Insulated Wire- Medical Grade Silicone Applications

Silicone insulated wire and cable is an excellent choice for medical cable applications. Besides being extremely flexible, silicone rubber can withstand autoclave and other forms of sterilization. Properties that make silicone suitable for medical applications include: Low thermal conductivity, low chemical reactivity, low toxicity and thermal stability (consistency of properties over a wide temperature range of 100°C to 250°C). Abrasion resistance is a concern when considering silicone insulation or jacket. Formulas for higher tear strength are available to increase resistance to abrasion.

Applications suitable for silicone cables include:

• Arthroscopic
• Surgical Robotics
• Electrosurgical
• Implantable
• Ophthalmic
• Foot Switch
• Patient Monitoring

What makes a material medical grade? Materials are tested for bio-compatibility and are categorized to be used for medical applications. Medical grade materials are generally grouped into three categories: non implantable, short term implantable and long-term implantable. Materials approved as USP Class V and VI can be considered medical grade, most medical grade silicone is at least Class VI certified.

Uses for medical grade silicone cables include:

• Tubing/Lumen
• Drains
• Feeding tubes
• Catheters
• Implants for long and short term use
• Sensors

Co-extruded and multi-layer silicone cables can be used for high voltage applications such as X-Ray and MRI equipment which require electrical noise suppression and limited power loss . Co-extrusion involves extruding a semi-conductive silicone layer around the conductor to remove air thus reducing corona. Extruding both semi-conductive layer and jacket simultaneously insures no air or particles are caught between the layers. Benefits for co-extruded silicone include corona, moisture & ozone resistance, lightweight and flexible cable design and radiation resistance to name a few.

When working with your custom cable manufacturer, it is crucial to provided them as much information as possible about the application, the environment, sterilization and bio-compatibility requirements. The more information you can provide to your silicone cable manufacturer will help in determining if silicone is right for your application and to offer you material choices that will enhance your product's performance.

Medical Cables: Often Overlooked

Medical cables are as important to a medical device as the device itself. Medical device designers many times focus on the device and overlook the wire and cables that is needed for the device to perform its function. Medical cables tend to be more specialized due to the many types of uses and environments it is subjected to. The wire and cable is many times not thought of until the end of the design process, which may be too late. Knowing your medical cable limitations and the options available to you in the beginning is important especially when designing housing or specifying connectors. Some things to keep in mind when specifying wire and cable for a medical device:

• Size- With the size of devices becoming smaller many times smaller gauge wire and cable is needed. Off the shelf wire and cable usually go as small as 28AWG. Fine wire and custom cable designs are usually needed.
• Flexibility- Handheld devices and medical robots require flexible cables which can withstand repetitive flexing. Higher stranded conductors and sometimes alloys are needed to achieve this.
• Sterilization- Sterilization can be done with alcohol, steam or gamma to name a few. Cable jackets need to withstand the sterilization process.
• Bio-compatibility- Medical grade cables are needed depending on the level of contact with the patient. Bio-compatible and implantable grade compounds are available for medical devices.
• Construction- Cables sending signals, power and even gas/fluid can be constructed in on jacket. Constructions can vary from the simple wire to complex hybrid cable.
• Unique- Medical devices are all unique in regards to application, requirements and environment. You should not use an off the shelf mass produced cable designed for to meet the generic needs of a variety of industries for a specialized medical device.
  

Considering your wire and cable needs from the early stages of your product design will prevent problems down the line in regards to failures in the field, design issues and time constraints. Designing custom medical cables for your application ensures you have a medical device that will exceed performance and longevity you require.

Depending on the type of use a variety of medical grade insulation materials are available. Reusable medical cables are built to endure constant flexing and extended cycles of sterilization. Insulation may be Teflon®, TPE or silicone rubber with TPR or silicone jackets. For disposable medical cables PVC and PE are the insulation most commonly used. Discuss your application with your custom cable manufacture in order to choose the right material for your medical device.

Working with a custom wire and cable manufacture is easier than you think. Custom wire and cable engineers work with you every step of the way to determine and suggest the best materials and construction for your medical application. It's like having a wire and cable expert on your team. Cable designs are usually modified throughout the design process to accommodate changes to the device design. Many custom wire and cable manufacturers are able to produce small quantities for prototypes and clinical trials.

Custom Cables: Quality Counts

There are plenty of jobs in the world that require some sort of cable. Because these jobs are so diverse, most hardware and home improvement stores carry all kinds of different cable. But even with this level of variety, not every cable need can be met by a local hardware store. For special jobs, it may become necessary to order flexible cables from a cable manufacturer. There are many reasons why a company might need to purchase a custom-made cable, but there aren't too many places to get cable made exactly to your specifications. That's why, when you find a good one, you've got to hold on to them.

If you need a specific type of silicone wire, then a company that makes custom cables might be able to make exactly what you need. Silicone is a great material for wire because it's heat-resistant, extremely flexible and durable, and it doesn't stick to things. If you need a special type of wire for a delicate job, then silicone is an excellent material to choose for the job. The problem is more one of finding someone who makes wire with this material than of figuring out what material you should use.

The aerospace industry is an industry that often needs custom wire and cables made. Because precision and durability are key in aerospace applications, it is of utmost importance for silicone cables to be of the highest possible quality and durability. If you skimp on cost in the aerospace industry, you're playing with people's lives just to save a few dollars. It's definitely worth the money to have custom wire made that is sure to do the job that you need done, as opposed to opting for the next-best thing or any other cheaper alternative to your first choice of material.

If you need super flexible custom cable, silicone is also an excellent choice. It bends easily and doesn't lose elasticity with movement. Some materials lose their elasticity the more you move them around, but not so with silicone. There are all different kinds of wire out in the world, and not all of them are cheap. But, in some cases, it's not about how much something costs. It's about how effective and durable that product is because a high-quality could make a life-saving difference in practice. And it's worth the money to keep people safe as they push the boundaries of what mankind can accomplish. For additional information, visit http://www.calmont.com/ to learn more.