Subscribe to our newsletter to receive the latest news and events from TWI:

Subscribe >
Skip to content

Joining Al Stranded Cable Using Rotary Friction Welding

Overview

TWI conducted a series of trials using rotary friction welding (RFW) to join stranded aluminium cable to aluminium bar as a proof-of-concept for using the technology to join two segments of aluminium stranded cable. If proven successful, RFW would be a significant improvement over the current and more conventional TIG and MIG welding process. RFW will offer a cost-effective, efficient, high-speed, automated solution to the issues currently faced by industry – particularly for land and subsea cable.

The objectives of this initial project was to:

  • Assess the feasibility of joining aluminium stranded cable to a solid aluminium puck using RFW
  • Assess the joint strength of the cable-to-bar weld
  • Produce proof-of-concept demonstrators

What We Did

The project was split into several stages including (i) design and manufacture of fixturing for RFW; (ii) design and preparation of aluminium puck/blank and cable; (iii) parameter development trials; (iv) assessment and mechanical testing of the joints.

Work was conducted at TWI using one of our RFW systems operated by a friction welding specialist.

The project was conducted through internal investment and the support of Power CSL, who provided the aluminium stranded cable and additional industrial insight.

 

Key Results

  • Stranded aluminium cable was successfully joined to solid aluminium bar using RFW
  • A “double-sided” welded demonstrator of two cables joined together via a solid Al puck was also successfully produced using RFW
  • Pull testing of the welded specimens showed variation in the mechanical properties between the inside and outside cable strands. The central cable remained joined to the Al puck after pull testing, suggesting superior mechanical properties. Future work would look at achieving uniform properties across the joint

 

Next Steps

This project has demonstrated the feasibility of using RFW to join stranded cable. The next steps will be to build upon the outcomes of this initial project to investigate ways to increase the mechanical performance and uniformity of the joint, as well as exploring how to upscale this for industrial applications.

Additionally, TWI would like to improve the efficiency of the process by minimising or removing the requirement to remove the water-blocking compound prior to welding.

If you would like to find out more, or are interested in working with us to continue developing RFW as a way to join stranded cable, please email contactus@twi.co.uk.

Figure 1. Single-sided RFW stranded aluminium cable to aluminium bar
Figure 1. Single-sided RFW stranded aluminium cable to aluminium bar
Figure 2. Double-sided RFW stranded cable to stranded cable via small aluminium puck
Figure 2. Double-sided RFW stranded cable to stranded cable via small aluminium puck
Avatar Emily Davison Project Leader - Laser Additive Manufacturing

Dr Emily Davison joined TWI as a Project Leader in the Laser Additive Manufacturing (LAM) section in 2018. Her current role focuses primarily on Laser Metal Deposition (LMD) technologies, including leading the development of wire LMD (w-LMD) capabilities at TWI’s Yorkshire facilities. She completed her PhD at the University of Sheffield in 2020, investigating LMD parameter optimisation for repair applications.

}