Klamath No Longer Copes with Valve Problems

The Klamath Cogeneration plant, located in the Klamath basin of Southern Oregon , has been recognized as a model facility for its advanced design, high efficiency, low-cost of operation, and superior environmental stewardship. In fact, the 484-megawatt natural gas-fired combined cycle cogeneration facility was awarded Power Magazine’s Power Plant of the Year Award in 2001. That was over three years ago.

In early 2004, Klamath Plant Engineer Bruce Willard approached CCI regarding a desuperheater downstream of the plant’s Copes high-pressure (HP)bypass steam valve. Willard was looking to design a new desuperheating station and isolation valve station to help with servicing and protecting the HP bypass valve.

It became clear to both Pacific Klamath Energy officials and CCI engineers that the Klamath Cogen facility had serious issues with its existing HP bypass systems, with problems ranging from bent stems, sticking valves, and leakage to deteriorating performance and overall reliability. Such matters are critical since the HP bypass systems are very severe; their failures can result in huge financial losses and significant property damages.

With such a crucial application at stake, Willard called on The Severe Service Doctor™ and was pleasantly surprised to learn that CCI could solve all of the plant’s problems by replacing the entire HP bypass system. What is more, CCI could do so in less than 12 weeks.

CCI’s solution included two complete HP bypass systems, each comprising

• One 8x12-inch 100D globe valve
• One BTG DAM-D desuperheater and
• One 2x2-inch 100DSV spray valve

Visible exterior damage is a telltale indicator of internal problems.

The 100D steam valve features CCI’s multi-stage DRAG® velocity-control trim to control the high-pressure letdown as the HP steam is bypassed to the cold reheat line. DRAG® trim divides flow into many streams and each flow passage consists of several turns, each of which reduces the pressure of the flowing medium.

These large pressure drops are just one of the characteristics of this application that make it severe. The system must also be able to handle large thermal gradients as the 1050ºF (566ºC )inlet steam is cooled to cold reheat temperature levels. During operation, the steam valve is often exposed to dramatic, rapid temperature increases upward of 500ºF (260ºC). Designers must take this into consideration when choosing materials and designing for clearances and tolerances between close moving parts. With over 40 years of experience in severe service applications, CCI knows how to design the right valves for these harsh conditions.

Since their installation, Klamath Cogen’s HP bypass systems have demonstrated excellent performance, proving the value of CCI’s multi-stage DRAG® trim combined with decades of valve design experience. Those at the plant have been delighted to see their plant reliability numbers up and their plant startup headaches cured as the system performs exceptionally well under all circumstances. According to Willard, “The operators kiss me nearly every morning since we installed the CCI DRAG® valves and our valve contractor has started pumping gas on the weekends to make up for lost income. ”

Largely due to the outstanding performance of CCI’s HP bypass systems, Klamath Cogen has now purchased nearly $1 million in CCI solutions over the past two years. Talks about plant performance and reliability led to a discussion about Klamath Cogen’s HP feedwater regulators, which accounted for problems due to leakage and poor control. The plant has since replaced its troubled Fisher two-valve system with a single CCI DRAG® 100 DLC feedwater control valve.

Additionally, Klamath Cogen has purchased two complete CCI hot reheat (HRH) bypass systems to replace its current Copes HRH bypass systems. These DRAG® solutions have shipped to the site and will be installed during the facility’s spring outage this year. Eagerly awaiting the installment of these systems, personnel at Klamath Cogen are looking forward to even higher returns on their investment in CCI.

As The Severe Service Doctor™, CCI takes great pride in its ability to solve customers’ problems, especially those involving extremely severe and highly visible applications. Operating with several CCI solutions installed and running well, the Klamath Cogeneration Plant can anticipate many more years of award-winning plant performance.

Published in SOLUTIONS Summer 2005