Identify Thread Type: It is easiest to use a thread gauge to determine the thread pitch (threads per inch or mm).
Measure Diameter: For best results, use calipers to measure the outside diameter (male connectors) or inside diameter (female connectors).
Identify Sealing Method:
Tapered (NPT/NPTF/BSPT): Seal via thread deformation; thread diameter reduces towards the end.
Parallel/Straight (ORB, BSPP): Seal via O-ring or washer on the port.
Flare (JIC 37°, SAE 45°): Seal via mating angled faces.
SAE Straight Thread (ORB/O-Ring Boss): Recommended for high-pressure systems to prevent leakage; features straight threads and a 90-durometer O-ring.
JIC (Joint Industrial Conference): 37° flare connection, popular for hydraulic fluid systems.
NPTF (National Pipe Tapered Fuel):Dryseal pipe thread often used in fluid power applications, needing sealant.
BSPP/BSPT (British Standard Pipe): Common in international equipment; BSPP (parallel) has a 60° cone, while BSPT (tapered) is common in Australian/European, and some Japanese systems.
Metric (DIN): Commonly used in Europe, including DIN 7631 (straight) or DIN 2353 (24° cone).
Avoid over-tightening NPT fittings, as it can crack the connector.
Check compatibility: Do not confuse JIC (37°) with SAE 45-degree fittings, as they look similar but have different flare angles.
Use Tools: Always use a thread identification kit or a thread pitch gauge for accuracy.
