Examples of The Society of Automotive Engineers (SAE) for John Deere TractorsBy
North American Thread Types
There are many different types of threads and connectors including the North American, British, French,German and Japanese. They are identified by the geographic regions where they are utilized. Thisdocument will only address the North American or National styles of connectors.
There is a wide array of adapters available to convert one type of fitting to another. Typically, John Deere equipment utilizes O-ring Boss on transmissions or valves, JIC for hydraulic lines, NPTF on hydraulic couplers, and OFS for some cylinders.
National Pipe Tapered Thread Fuel (NPTF)
This is a dry seal type of thread; the National pipe tapered thread for fuels. This is used for both male and female ends. The NPTF male will mate with the NPTF, NPSF, or NPSM female.
The NPTF male has tapered threads and a 30° inverted seat. The NPTF female has tapered threads and no seat. The seal tales place by deformation of the threads. The NPSM female has straight threads and a 30° inverted seat. The seal takes place on the 30° seat.
National Pipe Straight Thread Fuel (NPSF)
The National pipe straight thread for fuels. This is sometimes used for female ends and properly mates with the NPTF male end. However, the SAE recommends the NPTF thread in preference to the NPSF for female ends.
National Pipe Straight Thread Mechanical (NPSM)
National pipe straight thread for mechanical joint. This is used on the female swivel nut of iron pipe swivel adapters. The leak-resistant joint is not made by the sealing fit of threads, but by a tapered seat in the coupling end.