Coils play a crucial role in many medical devices and components. In catheters, coil-reinforced tubing improves kink resistance and pressure holding. In guidewires, coils provide reinforcement, additional flexibility and radiopacity. 

In addition to these interventional cardiology applications, coils are widely used across imaging, cardiac rhythm management and neuroscience device segments. As hospitals move increasingly towards minimally invasive techniques using smaller devices, manufacturers are seeking to reduce coil diameters while maintaining both precision and performance.  

For example, in cardiovascular surgery, recent research by GlobalDatai suggests the development and success of transcatheter procedures have created a strong market for more specialised accessories and medical devices, such as catheters that can deliver surgical devices for cutting, manipulating, ablating and replacing valves.  

The need for multiple guidewires and catheters in certain procedures presents an opportunity for manufacturers to develop products that can reduce the number of exchanges, increasing efficiency and cost-effectiveness. Additionally, the continuous progress in transcatheter procedures opens up new markets and opportunities for the medical device industry to capitalise on. 

Coiling coils 

As a result of the specialised equipment and skills required, coil production is usually outsourced to specialist manufacturers. Outsourcing is viewed as a cost-effective way to create proof-of-concepts for innovative devices and support commercial manufacturing. 

An OEM’s complete guide to sourcing coils for medical devices is a brand-new whitepaper from Custom Wire Technologies, which presents an expert’s guide to sourcing coiled components. 

The paper looks at key concepts, as well as current market conditions and trends, before discussing what you should look for when choosing a coiling partner to obtain the maximum benefits. 

Coil designs are determined by several key factors that affect their performance, such as size, material and winding direction. The paper examines all these factors, besides manufacturing methods and specialist techniques. 

Key takeaways include: 

  1. Sizing  
    Medical coils typically have outer diameters of 0.008in to 0.032in, and come in various lengths, depending on their application. Micro coils used in guidewires, on the other hand, can have wire diameters as small as 0.001in. Maintaining precision in such small coils presents significant challenges, which are most easily overcome with the help of a specialist. 
  1. Materials  
    Stainless steel, nitinol, titanium and cobalt chrome are all used in coil manufacturing, along with some precious metals, including gold, silver, platinum and platinum alloys. Each one offers its own benefits and challenges.  
  1. Coil style  
    Coils can be unifilar (single wire) or multifilar (two or more wires), depending on the number of wires wound. Pitch and stiffness are key specifications, while wind direction is another consideration. 
  1. Manufacturing methods  
    There are two ways of building a coil: point coiling and mandrel winding. Both procedures can be used to make parts with the same requirements, but each has features that can alter the coil’s performance.  

The experts: Custom Wire Technologies (CWT)  

When it comes to choosing a coiling partner, to fully reap the benefits of outsourcing, you need to choose a manufacturer with decades of expertise who offers value-added services and proven methods that save time. 

Custom Wire Technologies (CWT) is a Wisconsin-based company that bills itself as a “one-stop shop for OEMs seeking precision medical wire products”, according to founder and president Bob Boldig.  

When the company was established in 2002, it started with coil production, adding more vertically integrated value-added services as it grew. Boldig believes CWT’s personal service is an advantage for its customers. 

“The thing that I think separates us from a lot of companies is that we’re very nimble and quick to respond,” he says. This is particularly true of CWT’s QwikCoil programme. This unprecedented service can deliver up to 20 bespoke coils in one week or less.  

Boldig says: “This programme allows them to build prototypes much faster for their customers and was designed with engineers in mind.” 

CWT’s technical experience also sets it apart in the medical coiling space. 

“We have been making coils for over 20 years and have seen a multitude of applications using numerous sizes of materials, making thousands of sized and shaped coils. Our manufacturing experience gives us the upfront knowledge as to what works,” says Boldig. 

To learn more about coiling, download CWT’s brand-new whitepaper below.