NPT vs MIP Fitting

Here is a brief comparison table between NPT vs MIP fitting that is used in piping systems.

NPT vs MIP Fitting

Stand forNational Pipe Tapered threadsMale Iron Pipe
Known asANSI/ASME B1.20.1 pipe threadsCopper or steel fittings
MaterialPVC, PlasticIron, copper, stell, pvc, plastic
ApplicationResidential water & hydraulic systemsResidential, commercial and industrial piping systems
NPT FittingMIP Fitting
ShapeAngle between taper and center axisStraight
Pitch measuringThreads per inche (TPI)Threads per inche (TPI)
Truncation of roots and crestsFlatFlat or not
High-pressure applicationsNot recommendedRecommended
TighteningGeneral tightening standard is recommnededN/A
CompatibleFNPT fittingsFIP fittings
SealantSealant compound or PTFE (Polytetrafluoroethylene) tapePipe dope or Teflon tape

NPT and NPT fitting

NPT stands for National Pipe Taper which refers to residential-grade pipe systems. An NPT fitting is a National Pipe Tapered threads fitting that can be used with FNPT (female NPT) fitting in residential water and hydraulic systems.

NPT vs. MIP fitting

MIP and MIP Fitting

MIP stands for Male Iron Pipe which refers to heavy-duty-grade metal pipe systems. A MIP fitting is a metal threaded piping fitting that can be used with a FIP (female iron pipe) fitting in heavy-duty piping systems for both residential and industrial uses.

MIP and NPT Fitting


Are MIP and NPT threads compatible?

MIP (Male Iron Pipe) and NPT (National Pipe Thread) threads are compatible in the sense that they can physically thread together. Both MIP and NPT threads have the same basic thread profile and pitch, so you can typically connect a male MIP-threaded component to a female NPT-threaded component and vice versa.
However, there is a key difference to keep in mind when using these threads together is sealing method.
MIP threads are straight threads and rely on the use of a sealing compound or tape to create a watertight seal when connecting two threaded components. NPT threads, on the other hand, are tapered and designed to create a seal as they are tightened. NPT threads are typically self-sealing and do not require additional sealing compounds.
Because of this difference in sealing method, when connecting a MIP thread to an NPT thread, you may need to use sealing tape or a suitable sealing compound (like pipe thread sealant) to ensure a proper seal and prevent leaks. It’s essential to apply the sealing material correctly to achieve a watertight connection.

Is MIP the same as NPT?

MIP (Male Iron Pipe) and NPT (National Pipe Thread) threads are not the same, although they are often used interchangeably in casual conversation. There is some overlap in terminology, which can lead to confusion.