Fixing Customer Challenges with Innovative Design
Custom Product from Coiling Technologies, Inc.
Coiling Technologies recently partnered with a customer facing repeated failures in their steam valve springs. These failures occurred during high-temperature operations, where traditional carbon steel springs were unable to maintain load over time—resulting in costly plant shutdowns and operational disruptions.
To address this challenge, our engineering team developed a spring using Inconel X750, a nickel-based superalloy known for its high strength and resistance to extreme temperatures. The resulting design featured a large Inconel Spring with the following specifications:
- Bar diameter: 2.350 inches
- Free length: 21.250 inches
- Outer diameter: 17.250 inches
- Weight: 307 lbs or 139.22 kg
Due to tight packaging constraints, we incorporated a presetting process to enhance the spring’s reliability and performance in high-temperature environments. A critical step in the manufacturing process, presetting (also known as skragging), improves spring durability by enabling it to handle higher stresses and increased loads. This technique involves compressing or extending the spring beyond its elastic limit, causing plastic deformation, and inducing beneficial residual stresses throughout the material.
When the spring is later subjected to operational loads in the same direction as the presetting, these residual stresses counteract the applied stresses. This process improves the spring’s fatigue life, ensuring it can endure repeated loading without yielding—critical for avoiding valve failure.
Additionally, presetting enables the use of higher stress values, allowing our engineers to reduce the wire diameter and overall spring mass. This not only leads to a more efficient design but also results in cost savings—a major advantage when working with super alloys like Inconel X750, which can cost 30 to 40 times more than standard carbon spring steel.
At Coiling Technologies, we are committed to providing cost-effective solutions that reduce downtime and enhance operational efficiency. Whether it is solving high-temperature challenges or optimizing your spring design, we ensure your systems are back online—faster and more reliably.
