Overmoulding Enables The Development of Haldex Splitter Cable

Haldex splitter cable uses Overmoulding

Haldex is a manufacturer of brake products, air suspension systems and products to enhance safety for heavy vehicles. Gabor Novek, Production Planner at the company, describes some of the issues and challenges involved in the recent development of a splitter cable used on the EB+ Gen 3 electronic braking system and how overmoulding proved to be the solution.

“This part is a splitter cable which is used with our EB+ Gen 3 electronic braking system. The function of the part is to allow two separate cables to be plugged into this adapter which in turn connects to a single port on our ECU. This is important as it allows our customers the freedom to have their systems set up in a more versatile way, enabling them to connect and control more Auxiliary products than could normally be catered for from our EB+ products.”

“The challenge when creating this part was finding a cost-effective way of effectively splicing and sealing three cables together. Our products are fitted to the underside of commercial vehicles (trailers) and so must withstand harsh environments and therefore require IP69 compliance. We therefore had to find the right balance of keeping the material usage as low as possible, whilst still maintaining enough of a protective barrier without the parts succumbing to water ingress, especially after thermally cycling our products during validation testing.”

“Overmoulding is a very cost effective solution for providing sealing and strain relief. For early concepts of this product, we had looked at using adhesive lined heat-shrinkable boots, and whilst they worked perfectly, the cost of the product was far too high. Overmoulding is a technology that we moved over to quite a few years ago, so was the natural choice for a production solution to seal our products. It also has the benefit of giving a far more professional end look for our customers.”

“On typical connectors that have single wire seals / mat seals, the sealing aspect of the overmoulding is more of a backup method of sealing. However, for this product the overmoulding is the primary method of sealing. When the product was initially designed, we used PA646, which is a standard low-pressure overmoulding material that we had used on other products. However, we quickly saw sealing issues due to breaks in adhesion between the overmoulding and our PVC cable during environmental testing that led to water ingress issues. After discussions with engineers at Overmould we decided to trial Technomelt PA657 due to its inherently better adhesion to a range of different materials. The results showed an instant improvement and allowed us to develop the product into what it is today.”