Search results
Results from the WOW.Com Content Network
The standard designation for a UTS thread is a number indicating the nominal (major) diameter of the thread, followed by the pitch measured in threads per inch.For diameters smaller than 1 / 4 inch, the diameter is indicated by an integer number defined in the standard; for all other diameters, the inch figure is given.
The major minus pitch technique also works for inch-based threads, but you must first calculate the pitch by converting the fraction of threads-per-inch (TPI) into a decimal. For example, a screw with a pitch of 1/20 in (20 threads per inch) has a pitch of 0.050 in and a 1 ⁄ 13 in pitch (13 threads per inch) has a pitch of 0.077 in.
The thread form is defined by flats at the tip and root of the thread form. This flat length is defined as the pitch divided by eight. The thread depth, which is from flat to flat is 0.6495 times the pitch. [4] For 1 ⁄ 4-inch (6.4 mm) screws and larger, the pitch is defined as: = +
Camshaft cover stud threaded 1 ⁄ 4-20 UNC (left, for aluminium cylinder head) and 1 ⁄ 4-28 UNF (right, for steel nut; from a 1960s Jaguar XK engine) The common V-thread standards ( ISO 261 and Unified Thread Standard ) include a coarse pitch and a fine pitch for each major diameter.
From 1 ⁄ 4 in up to 1 + 1 ⁄ 2 in, thread pitch is the same in both systems except that the thread pitch for the 1 ... 1 + 1 ⁄ 8: 28.575 7: 3.629 0.9420 23.927 ...
In the case of M6-1.0, the rule of thumb that you mentioned, major minus pitch, yields a 5mm tap drill at ~75% thread. However, the tap drill that the chart mentions, 5.2mm, will give a ~60% thread, which is also acceptable, provided that a 60% thread is what the user wants.
For a taper thread, it is the diameter at the "gauge length" (plus/minus one thread pitch) from the small end of the thread. The taper is 1:16, meaning that for each 16 units of measurement increase in the distance from the end, the diameter increases by 1 unit of measurement.
The taper rate for all NPT threads is 1 inch of diameter in 16 inches of length (3 ⁄ 4 inch per foot or 62.5 millimeters per meter) measured by the change of diameter (of the pipe thread) over distance of thread.