Calculators & Tools

Pitch Diameter, Tap Drills, and the Logic Behind Our Unified Thread Calculator

Every bolted flange, every stud, every tapped hole on a piece of pressure-control equipment depends on a thread that was cut correctly — and “correctly” starts with a handful of geometric relationships that are older and simpler than most of the software built around them. Our Unified Thread Calculator puts those relationships in one place:

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Sizing Pipe Wall Thickness for a Target Design Pressure

“I need this pipe to hold 5,000 psi — what wall thickness do I actually need?” is one of the most common early-design questions we get, and it’s really just our Internal Yield (Burst) Pressure formula run backwards. This post walks through solving Barlow’s equation for wall thickness instead of pressure, and where that number

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Why Your String Weighs Less Downhole: The Buoyancy Factor Shortcut

Every string looks lighter once it’s in the hole. That’s not the rig lying to you — it’s buoyancy, and it’s why a driller’s hook-load reading never matches the pipe tally’s air weight once the string is wet. This post covers the shortcut oilfield engineers actually use to get from air weight to buoyed weight,

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Why Burst and Collapse Checks Alone Aren’t Enough: The Triaxial Envelope

Every calculator on this site so far checks one failure mode at a time: burst, or collapse, in isolation. Real strings don’t fail that way — pressure and axial load act together, and a pipe that comfortably passes a burst check and a collapse check separately can still yield when both loads are on at

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Torque Is a Proxy for Tension: The Logic Behind Our Flange Bolt Torque Calculator

Torque specs on a bolted flange look precise — “450 ft·lbf, three passes, star pattern” — but the number behind that spec is built from a chain of assumptions, and the weakest link in that chain is almost always friction, not the bolt itself. Our Flange Bolt Torque calculator walks through that chain explicitly so

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Flange Bolted-Joint Analysis: Why “It Passed Visual Inspection” Isn’t a Compliance Check

A flanged connection that looks fine — bolts torqued to spec, gasket seated, no visible gap — can still be one thermal cycle or one pressure surge away from a leak path. Visual inspection and correct installation torque confirm the joint was built right; they don’t confirm it was designed right for the loads it

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Choke and Kill Manifold Design: What Actually Goes Into Sizing One

A choke and kill manifold looks like a dense cluster of valves, chokes, and pipe spools, and sizing one properly means working through several interlocking decisions at once — pressure rating, choke sizing, redundancy, and line routing — each of which constrains the others. Here’s what actually goes into that. Start with the pressure rating

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