When a power generation facility needed to replace an obsolete 45-inch asbestos pressure seal, EGC’s engineering team designed a custom graphite pressure seal solution. Using a proprietary manufacturing process, EGC avoided expensive tooling, shortened production time, and delivered a replacement seal that installed successfully and performed as intended.
The Challenge: Replacing an Obsolete 45-Inch Pressure Seal
Power plants often operate critical equipment for decades, making replacement parts increasingly difficult to source. One power generation customer faced exactly that situation when it needed to replace a 45-inch diameter pressure seal used in a feedwater system check valve. The original seal was manufactured from asbestos, a material that has long since been phased out of industrial sealing applications.
The challenge extended beyond the material. At 45 inches in diameter, the seal was significantly larger than typical pressure seals, which generally range from 4 to 24 inches. The unusual size created additional manufacturing and engineering complexities.
Why Standard Replacement Options Wouldn’t Work
Finding a replacement for the original seal required more than a simple material substitution.
The customer needed a solution that would:
- Accommodate the valve’s existing dimensions and tolerances.
- Replace an obsolete asbestos sealing material.
- Avoid extensive modifications to the valve.
- Meet outage-driven timelines.
- Provide dependable sealing performance.
Traditional manufacturing methods also presented challenges. Creating a conventional die-formed seal of this size would have required custom tooling, significantly increasing both project costs and lead times.
The Engineering Solution
EGC engineers reviewed the customer’s valve drawings and evaluated the operating requirements. Based on the available space and valve design, the team determined that a graphite pressure seal would provide the most practical replacement solution.
The project required additional engineering innovation due to the seal’s size. Because standard manufacturing fixtures could not accommodate a 45-inch diameter seal, EGC developed a special fixture specifically for the application. The team then leveraged EGC’s proprietary manufacturing process to produce the seal without the need for costly custom dies.
This approach enabled the customer to receive a custom-engineered solution more quickly and economically than traditional manufacturing methods would allow.
The Results
By combining application expertise with manufacturing flexibility, EGC successfully delivered the replacement seal within approximately one week. The completed seal was shipped in a protective wooden crate and arrived the next day for installation.
The outcome was straightforward:
- Successful replacement of an obsolete asbestos seal.
- Custom solution for a highly unusual 45-inch diameter application.
- Reduced lead time compared to traditional tooling methods.
- Smooth installation.
- Reliable field performance.
Engineering Expertise for Uncommon Sealing Challenges
Many sealing applications can be solved with standard products. Others require a deeper level of engineering support, particularly when equipment is aging, original materials are obsolete, or dimensional requirements fall outside standard manufacturing capabilities.
This project demonstrates how EGC works with customers to evaluate unique valve sealing challenges and develop practical solutions that balance performance, cost, and delivery requirements. Whether the application involves a standard pressure seal or a highly specialized large-diameter design, EGC’s engineering team is prepared to help identify the right path forward.
Frequently Asked Questions
Can graphite replace asbestos pressure seals?
In many applications, graphite pressure seals can be engineered to replace obsolete asbestos sealing materials while providing reliable sealing performance. Application-specific evaluation is required to determine compatibility.
How large can a pressure seal be manufactured?
Seal size capabilities vary by manufacturer and process. In this application, EGC engineered and manufactured a custom 45-inch diameter pressure seal using specialized fixturing and proprietary manufacturing methods.
What are the advantages of custom-engineered pressure seals?
Custom-engineered pressure seals can help address obsolete materials, unusual dimensions, equipment-specific requirements, and demanding outage schedules while reducing the need for equipment modifications.
Need Help Solving a Difficult Sealing Application?
Whether you’re replacing an obsolete seal, supporting aging equipment, or facing an unusual valve sealing challenge, EGC’s engineering team can help evaluate your application and recommend a practical solution.
