Thread Compatibility Checker

NPT · BSPT · BSPP · JIS — for Threaded Flanges per ASME B16.5 / ISO 7

Flange Configuration

Compatibility Reference Matrix

FlangeMatingResultKey Note
NPTNPTCompatibleStandard North America / ASME B1.20.1
BSPTBSPTCompatibleStandard Europe/Asia; verify taper angle match
BSPTJIS RcConditionalSame taper (1:16), same pitch NPS ½–2″; verify size ≤2″
JISBSPTConditionalInterchangeable ≤2″ per JIS B 0203
NPTBSPTIncompatibleDifferent taper (NPT 1:16 pitch; BSPT 55° thread angle vs NPT 60°)
BSPTNPTIncompatibleThread angle mismatch — leak risk even if initial fit seems tight
BSPPAny taperIncompatibleParallel thread cannot form pressure seal with tapered thread
NPTBSPPIncompatibleTaper vs parallel — will not seal

Engineering Notes and Disclaimer

Thread compatibility assessment based on ASME B1.20.1, ISO 7-1, and JIS B 0203. “Conditional” entries require dimensional verification before use. Always confirm thread form with a calibrated thread gauge before assembly.

Trending now

Types of Flanges: 6 Main Types, Faces & Standards Guide
Types of Flanges Explained: How to Tell Them Apart and Choose the Right One
Weld Neck Flange: The Complete Engineering Guide (B16.5)
Weld Neck Flange: Dimensions, Classes, Materials & How to Choose One
Spiral Welded Pipe (SSAW): The Complete Buyer's Guide
Spiral Welded Pipe (SSAW), End to End: Process, Standards, Selection & QA
Concentric Reducer Guide: Types, Specs & Selection
Concentric Reducer: An Engineering Guide to Selection and Verification