Valve-Body

Subsea oil and gas components live at the bottom of the ocean, under thousands of meters of water and hundreds of bar of pressure. A failure down there is not something you can repair with a service truck. I have been drilling subsea components for over a decade, and the standards are higher than anything else I have encountered in machining. This article covers what I have learned drilling deep holes in subsea valve bodies, connectors, manifolds, and christmas tree components. If you are new to subsea work, start with my overview of oil and gas deep hole drilling and the deep hole drilling guide for stainless steel. ...

Oilfield gate valves control the flow of crude oil, gas, and drilling fluids. The valve body needs a through-bore for the gate that slides across the seat to open or close the flow path. The bore must be straight and round so the gate seals properly at high pressure. In my experience, a gate valve that leaks at rated pressure is almost always a bore concentricity problem, not a seat material problem. ...

When a bore comes out oversized, pressing in a thin-walled bushing can save the part. The process involves boring the damaged hole to a larger diameter, pressing in a bushing, then boring or drilling the bushing to the original size. I have used this technique on hydraulic cylinder barrels, pneumatic valve bodies, and machine tool housings. It is a reliable repair method when done correctly, but the details matter a great deal. ...

Hydraulic valve bodies are some of the most demanding components I have worked on in the industrial sector. The bores need to be straight, round, and smooth. The valve spool fits inside the bore with a clearance measured in microns. If the bore is off, the valve leaks or sticks. I have drilled valve bodies for mobile and industrial hydraulic systems. The principles are the same regardless of the valve size. ...