Thinking all metal probes resist high pressure is wrong dangerous failures can happen correct matching of material and pressure class (based on yield strength and wall thickness) is needed.5-Hole Pitotwelcome to click on the website to learn more!
Pressure resistance depends on material yield strength not just being metal. For example 304 stainless steel (yield strength 205 MPa) is only good for ≤10MPa, Inconel 718 (760 MPa) handles up to 40MPa with same wall thickness. A chemical plant had a 304 probe burst at 15MPa, replacing with Inconel 718 fixed it.
Wall thickness calculations need a safety factor of 4 (ASME standards) for high-pressure (>20MPa) apps. A 10mm probe for 30MPa needs 2mm walls in Inconel 718, but 5mm walls in 304 adding weight and disturbance.
Threaded connections are weak NPT threads need proper torque (30-40 N·m for 1/4" probes) and sealant (PTFE tape + anti-seize) to stop leaks. A test found under-torqued connections (20 N·m) leaked at 80% of rated pressure, correctly torqued ones held to 120%.
Steps to match material and pressure: 1) find max operating pressure (including spikes) 2) pick material with yield strength ≥ (pressure × safety factor / wall thickness ratio) 3) check connections for pressure class 4) test prototypes at 1.5x rated pressure.