4/23/2021 0 Comments Standard Nut And Bolt Chart
Use the dimensions of your bolt to determine the appropriate size nut.For example, a bolt and nut may be described as being diameter.But neither the external threads of the bolt nor the internal threads of the nut are exactly.500 in diameter.In fact, the bolt diameter is a little smaller and the nut diameter a little larger.
But it is easier to specify the components by a single size designation since the bolt and nut are mating components.). ![]() Coarse threads have a larger threadform relative to screw diameter, whereas fine threads have a smaller threadform relative to screw diameter. These fasteners are used to mechanically join or affix other hardware objects together, and come in many forms which include rivets, nuts, bolts, studs, screws, washers, eyebolts, nails, and threaded fasteners. These fastener standards allow hardware product manufacturers, as well as the end-users of such products, to examine and assess fasteners to ensure their strength and quality towards safe utilization. This is more like the modern mechanical screw and was used for fine machinery and for steel bolts. Until then, the only standardization was what little had been done by individual people and companies, with some companies in-house standards spreading a bit within their industries. Whitworths new standard specified a 55 thread angle and a thread depth of 0.640327 p and a radius of 0.137329 p, where p is the pitch. The thread pitch increases with diameter in steps specified on a chart. An example of the use of the Whitworth thread are the Royal Navy s Crimean War gunboats. These are the first instance of mass-production techniques being applied to marine engineering, as the following quotation from the obituary from The Times of 24 January 1887 for Sir Joseph Whitworth (18031887) shows. There were just ninety days in which to meet this requisition, and, short as the time was, the building of the gunboats presented no difficulty. It was otherwise however with the engines, and the Admiralty were in despair. Suddenly, by a flash of the mechanical genius which was inherent in him, the late Mr John Penn solved the difficulty, and solved it quite easily. He took them to pieces and he distributed the parts among the best machine shops in the country, telling each to make ninety sets exactly in all respects to the sample. The orders were executed with unfailing regularity, and he actually completed ninety sets of engines of 60 horsepower in ninety days a feat which made the great Continental Powers stare with wonder, and which was possible only because the Whitworth standards of measurement and of accuracy and finish were by that time thoroughly recognised and established throughout the country. On disassembly, all its threads were shown to be of the Whitworth type. The Unified thread angle is 60 and has flattened crests (Whitworth crests are rounded). 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 2 in bolt is 12 threads per inch (tpi) in BSW versus 13 tpi in the UNC. The sides are at a flank angle of 27.5 perpendicular to the axis. Thus, if the thread pitch is p, the height of the fundamental triangle is H p (2tan ) 0.96049106 p. However, the top and bottom 1 6 of each of these triangles is cut off, so the actual depth of thread (the difference between major and minor diameters) is 2 3 of that value, or h p (3tan ) 0.64032738 p. The peaks are further reduced by rounding them with a 2(90 ) 180 55 125 circular arc. This arc has a height of e H sin 6 0.073917569 p (leaving a straight flank depth of h 2 e 0.49249224 p ) and a radius of r e (1 sin ) 0.13732908 p. Confusion can arise because each Whitworth hexagon was originally one size larger than that of the corresponding BSF fastener. This leads to instances where for example, a spanner marked 7 16 BSF is the same size as one marked 3 8 W. In both cases the spanner jaw width of 0.710 in, the width across the hexagon flat, is the same. Thus it is today common to encounter a Whitworth hexagon which does not fit the nominally correct spanner and following the previous example, a more modern spanner may be marked 7 16 BS to indicate that they have a jaw size of 0.710 in and designed to take either the (later) 7 16 BSW or 7 16 BSF hexagon. The across-flats definition is the common standard today, and has been for many decades. The larger spanner in this photo is from the 1920s or earlier. Its face was polished to allow the size stamp to show well in the photograph. This example is American, but it illustrates the way that spanners for Whitworth fasteners were typically labelled.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |