Extending Chrome Rod’s Life Span with a Custom HVOF Solution: A HVT Case Study

In rail infrastructure, equipment durability is crucial to minimising downtime and managing costs. A major rail services provider in Australia and New Zealand faced frequent failures with traditional electroplated chrome rods, which typically required replacement after about 1,000 weld cycles. These frequent replacements increased costs and disrupted operations, making a more durable solution essential. HVT introduced a high-velocity oxygen fuel (HVOF) coating to significantly extend rod life, ultimately setting a new benchmark in the component’s efficiency.

Challenge: The Limits of Traditional Chrome Plating
Electroplated chrome is often used in industrial applications because it’s a low-cost option, providing a hard surface at a relatively low price. However, in a high-abrasion environment like that of rail maintenance, chrome plating can fail prematurely, leading to frequent replacements and unplanned downtime. Given that weld heads typically perform around 5,000 weld cycles annually, rods that fail after only 1,000–1,500 cycles impose significant downtime and operational costs. This highlighted the need for a more resilient solution capable of meeting the client’s high-performance demands.

Solution: Implementing HVOF Coating for Enhanced Durability
HVT applied a custom tungsten-carbide (WC) alloy using the HVOF process, known for creating dense, durable coatings that withstand high-abrasion and thermal stresses. Tailored to the client’s needs, this coating was designed to maximise wear resistance and reduce failures. The HVOF-coated rods were engineered to endure the harsh conditions of operating directly in the welding zone and maintaining functionality over an extended period/cycles.

Implementation and Testing
HVT worked closely with the client to simulate real-world conditions for testing, ensuring the rods would perform reliably in demanding environments. The HVOF-coated rods exceeded expectations, achieving a lifespan of approximately 8,000 weld cycles, eight times that of traditional chrome rods. Even after 8,000 cycles, the rods required only a polish to be returned to service, with the potential for achieving even more cycles. This durability reduced maintenance needs, minimised downtime, and maximised cost-effectiveness.

Results: Operational Efficiency and Cost Savings
The extended lifespan of the HVOF-coated rods minimised the need for frequent replacements, significantly reducing maintenance related disruptions. This increased operational efficiency allowing rail welding teams to focus on planned tasks rather than emergency replacements, creating a more predictable and manageable workflow. Additionally, the reduced downtime contributed to cost savings, as fewer replacements and repairs were needed, and the weld head could stay in service longer.

Conclusion
HVT’s HVOF coating solution provided a durable, resilient alternative to traditional chrome plating, revolutionising the client’s approach to rail maintenance. This case demonstrates how advanced engineering solutions from HVT can transform equipment reliability and cost efficiency in high-demand industries.

Whether you’re looking to fix a specific issue or overhaul your entire maintenance strategy, we can help. Find out how HVT’s solutions can make a difference in your operations.