What is the use of Three wire method ?
The accurate measurement of thread pitch diameter, which may be perfect as to form and lead, presents certain difficulties which result in some uncertainty as to its true value. The adoption of a standard uniform practice in making such measurements is, therefore, desirable in order to reduce such uncertainty of measurement to a minimum. The “three – wire method” of measuring thread pitch diameter, has been found to be the most generally satisfactory method when properly carried out, and is recommended for universal use in the direct measurement of thread plug and thread setting plug gauges.
How to Calculate Pitch diameter Unified national threads?
Pitch diameter Unified national threads calculator uses Pitch Diameter of Unified Nation Thread = Micrometer Reading Unified and National Thread-3*Wire Diameter of Unified Nation Thread+0.86603*Screw Pitch of Unified Nation Thread to calculate the Pitch Diameter of Unified Nation Thread, Pitch diameter Unified national threads is defined as the diameter where the thread thickness is equal to the space between the threads. Pitch Diameter of Unified Nation Thread is denoted by Dun symbol.
How to calculate Pitch diameter Unified national threads using this online calculator? To use this online calculator for Pitch diameter Unified national threads, enter Micrometer Reading Unified and National Thread (Mun), Wire Diameter of Unified Nation Thread (Gun) & Screw Pitch of Unified Nation Thread (Pun) and hit the calculate button. Here is how the Pitch diameter Unified national threads calculation can be explained with given input values -> 6993.449 = 0.00827-3*0.00128+0.86603*0.00296.