Neil JonesSteampath Engineer Repairs Division
I graduated from The University of Missouri – Columbia with a Bachelor of Science in Mechanical Engineering. I started my career working as a Process Engineer for a large brewery, focusing on heat recovery initiatives. I also worked as a Packaging Engineer, consulting for various consumer product companies. None of my previous experience has been nearly as rewarding as working in the power generation industry.
What do you do here at MD&A?
I am a Project Manager/Steampath Engineer at our St. Louis Repairs Shop. We perform a variety of repairs for Steam Turbine Rotors and Stationary Components. I follow a project from proposal to start-up, taking incoming data, making repair recommendations, generating drawings, and keeping the customer informed of our progress.
What’s the most important thing in fabricating a Nozzle Plate or Box?
The most important consideration in manufacturing a replacement nozzle plate or box is to correct the cause of failure without changing the critical features. For example, if a nozzle plate fails because of inadequate structural welds or material quality, it is most important to make those corrections without modifying the nozzle areas, pitches, axial and radial location, etc.
What are indications of Diaphragm Dishing?
The clearest indications of diaphragm dishing can be seen when the unit is open and the top is removed. The measured clearances between the diaphragm and the rotor will be smaller than the design values. These clearances should be recorded over time to help determine which stage of creep the diaphragm is in. If the dishing is severe, you can easily see the inner web moving toward the rotor or the outer ring shifting in the shell.
Once the diaphragm is removed, you may see the partitions pulling out of the sidewalls. We also take measurements in the shop which helps to determine if dishing has occurred.
What are the Typical Diaphragm Dishing Repair Methods?
Historically, diaphragms have dished due to creep. More recently, diaphragm dishing has been seen more often due to inadequate structural welds exacerbating the effects of creep. The typical repair involves machining out the existing structural welds, moving the diaphragm back to the correct axial position, and improving the depth and quality of the welds. If the diaphragm geometry allows, we may also add bridges on the admission side or increase the axial height of the partitions.
Occasionally, we find a diaphragm that has inadequate material strength. In that case, we can remove the steam path and install it in a higher strength material, or we can manufacture a new diaphragm.
What has been the best vacation spot you have been to?
I like visiting National Parks. My favorite for the view is Waterton Lakes National Park, but Yellowstone is also amazing.