American male fittings for hydraulic hoses

The AGN taper fittings category in the HYDRON online store includes professional straight male fittings with an external taper thread according to the American NPT (National Pipe Taper) and NPTF (Dryseal) standards, designated in commercial classification by the symbol C31 or series 6077. These are commonly used connectors designed for crimping on low-, medium-, and high-pressure flexible hydraulic hoses. AGN type connections are characterized by a 60° thread profile and taper convergence, which enables effective sealing on the thread turns using a suitable sealant (liquid thread sealant or Teflon tape) or sealing on the internal 60° cone seat.

Technical specification and construction of AGN (NPT) fittings

NPT taper thread fittings are distinguished by specific construction features that determine their reliability in pressure installations:

• Self-sealing NPT / NPTF taper thread: The thread with a 1:16 taper ratio and a 60° flank angle wedges during screwing into the seat, eliminating gaps and ensuring high resistance to leaks.
• Sealing on the thread or 60° internal cone: The fitting can seal directly on the thread turns using Teflon tape or anaerobic sealant, or in the case of connection with a fitting with an internal cone – by pressing the 60° cone.
• High-quality free-cutting steel with zinc protection: Fitting bodies are made of free-cutting steel protected with a galvanic zinc coating, providing resistance to corrosion, mechanical damage, and working oils.
• Special variants for extreme high pressures (700 bar): The offer also includes specially reinforced NPT taper fittings dedicated to ultra-high-pressure flexible hoses (e.g., for hydraulic wrenches, spreaders, and Enerpac 700 bar pumps).

Wide range of thread sizes and hose diameters

In the HYDRON store, we have a full dimensional range of AGN taper fittings series C31 / 6077, matched to standard internal diameters of 1SN, 2SN, 1SC, 2SC, and 4SP/4SH hydraulic hoses:

• DN05 (3/16") and DN06 (1/4"): 1/8" NPT, 1/4" NPT, 3/8" NPT threads.
• DN08 (5/16") and DN10 (3/8"): 1/4" NPT, 3/8" NPT, 1/2" NPT threads.
• DN13 (1/2") and DN16 (5/8"): 3/8" NPT, 1/2" NPT, 3/4" NPT threads.
• DN20 (3/4") and DN25 (1"): 3/4" NPT, 1" NPT threads.
• Large diameters DN32 (1.1/4"), DN40 (1.1/2") and DN50 (2"): 1.1/4" NPT, 1.1/2" NPT and 2" NPT threads.

For the food, chemical, and marine industries, we also offer AGN fittings made of AISI 316L / 1.4571 acid-resistant stainless steel.

Application in industrial machinery and equipment

AGN taper fittings are commonly used in American, Asian, and European equipment, including Caterpillar, Bobcat, Case, John Deere construction machinery, pressure units, washers, pneumatic systems, lubrication equipment, and high-voltage 700 bar hydraulics.

Frequently Asked Questions (FAQ)

What is the difference between an AGN fitting and an AGJ fitting?

The AGN fitting has an American NPT taper thread that seals on the thread. The AGJ fitting has an American UNF straight thread with a 37° external cone (JIC) and seals on the cone face.

Do you always need to use Teflon tape when screwing in an AGN NPT fitting?

For NPT taper connections screwed directly into a threaded body, it is recommended to use liquid anaerobic sealant or Teflon tape to fill micro-gaps on the thread turns and guarantee 100% leak-tightness under high pressure.