National Mechanical Engineering Services LLC (NMES) has executed the first successful job with the V-Tec Orbit 24. At the end of 2009 a critical 12in 1500 pound flexible wedge gate valve got jammed. The wedge was stuck in the seats and after several failed attempts to free the wedge under bypass the twin-unit gas-fired combined-cycle plant went into an undesired shut-down. As an added factor this plant has a large capacity desalination section, making it (in the desert) of the utmost importance to bring in the right tools (and people) to keep the downtime as low as possible. NMES was contracted for this very urgent repair and took on this responsible job. After carefully cutting through means of a thermic lance and jacking the wedge out, the hard stellite valve- and wedge seats were found to be severely damaged by the harsh process circumstances and heat treatment during the disassembly. The Orbit 24 was successfully utilised to first quickly grind away the damages and restore the level of flatness, followed by fine finishing and lapping to recover the desired level of tightness.
