SCREW THREADS. = minor diameter. d 3. d 2. = pitch diameter

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1 ISO : 6 Part 2 DIN : Part /20 Metric (ISO) screw thread, coarse series -M- T-00 T-002 for M to incl. M,4, fit H/6h The bold lines indicate the maximum material profiles. The maximum material profile of the internal thread is the basic profile. B = basic major diameter Limits of sizes for metric screw thread, coarse series, fit 6H/6g ) d = major diameter d for M, 6 and greater, fit 6H/6g D = major diameter D D 2 Section at Stress Basic 2) Pitch External thread tol. 6g ) (bolts and screws) Internal thread tol. 6H ) (nuts) minor dia. area 2 (d2 + d)2 diameter major diameter pitch diameter minor diameter pitch diameter minor diameter π /4 d π /4 2 B = D min P d max d max D min D max mm 2 mm 2 ) 0,2,000 0, 0,88 0,8 0,6 0,60 0,88 0,84 0,2 0,8 0, 0,460, ) 0,2,00,0 0,8 0,88 0, 0,0 0,8 0,4 0,82 0,88 0,44 0,88,2 ) 0,2,200,,08 0,8 0,8 0,80,08,04 0,2 0,8 0,626 0,2,4 ) 0,,400,2,20,4,02 0,64,20,26,0,42 0,8 0,8,6 0,,8,46,4,2,2,0,,48,22,2,0,2,8 0,,8,66,4,4,2,2,,68,42,2,44,0 2 0,4,8,886,2,64,40,40,40,80,6,6,88 2,0 2,2 0,4 2,80 2,080,888,8,628,40,08 2,00,,88 2, 2,48 2, 0,4 2,480 2,80 2,88 2,,28,840 2,208 2,0 2,0 2,8 2,80, 0, 2,80 2,84 2,6 2,80 2,6 2,2 2,6 2, 2,4 2, 4,4,0, 0,6,4,4,08,004 2,4 2,6,0,222 2,80,00 6,000 6,8 4 0,,8,88,2,4,,002,4,66,242,422,4 8,8 4, 0, 4,48 4,8,,0,8,4 4,0 4,,688,88 0,0, 0,8 4,6 4,826 4,46 4,6,,86 4,480 4,60 4,4 4,4 2,6 4,2 6,4,4,24,22 4,4 4,6,0,00 4,,,8 20, 6,4 6,4 6,24 6,22,4,6 6,0 6,00, 6, 26,8 28, 8,2,2,60,60,042 6,48 6,22,88,48 6,64 6,2 2,84 6,6,2 8,2 8,60 8,60 8,042,48,22 8,88 8,48,64,2 4,8 48, 0,,68,2 8,4 8,862 8,28,8,026,206 8,6 8,66 2,0 8,0, 0,68 0,2,4,862,28 8,8 0,026 0,206,6,66 6,0 2, 2,,66,0 0,82 0,6,8,602 0,86,06 0,06 0,44 6,2 84, 4 2,62,682 2,66 2,0,08,2 2,0 2,,8 2,20 04, 6 2,62,682 4,66 4,0,08,2 4,0 4,,8 4,20 44, 8 2,,8,62 6,4 6,64 4,8 4,62 6,6 6,600,24,44, 20 2,,8,62 8,4 8,64 6,8 6,62 8,6 8,600,24,44 22, , 2,8 2,62 20,4 20,64 8,8 8,62 20,6 20,600,24,44 28, ,2 2, 22,00 2,80 20,2, 22,0 22,6 20,2 2,22 24, 2 26,2 26, 2,00 24,80 2,2 22, 2,0 2,6 2,2 24,22 42, 4 0, 2,4 2,22 2,64 2,462 2,6 2,06 2,2 28,00 26,2 26,,0 6, 2,4 2,22 0,64 0,462 28,6 28,06 0,2,00 2,2 2, 64, ,40,46,42,8,0 0,6,402,02,60 2,20, 8 4 8,40 8,46 6,42 6,8 4,0,6 6,402 6,02 4,60,20, , 4, 4,4,04 8,8 6,46 6,00,0,2,2, , 44, 44,4 42,04 4,8,46,00 42,0 42,2 40,2 40, ,2 4, 44,68 44,4 4, 4,2 44,2 4,08 42,8 4,2 4 2,2, 48,68 48,4 4, 4,2 48,2 4,08 46,8 4, ,,2,6 2, 2,088 4, 48,00 2,428 2,8 0,046 0, ,,2,6 6, 6,088, 2,00 6,428 6,8 4,046 4, ,20 6,20 60,02,4 6, 6,048 60,0 60,48,0 8, ,20 6,20 64,02 6,4 60, 60,048 64,0 64,48 6,0 62, For basic diameters above 68 mm see: metric screw thread, fine series. For coated threads the maximum values of d, and d are equal to the values of the basic profile ( = and d max = D min.) - ) the values for sizes to incl.,4 mm correspond to the fit H/6h. - 2) metric screw thread is designated by the basic diameter, preceded by the profile letter M and followed by the tolerance grade, e.g. 6, and the tolerance position, e.g. g. Example: M0-6g. If no toleranceclass is indicated the above mentioned fits are valid. A d A s 0 --

2 ISO : 6 Part 2 DIN : Part /2/22/2 Metric (ISO) screw thread, fine series - MF- Limits of sizes for metric screw thread, fine series, fit 6H/6g Section at Stress Basic 2) Pitch External thread tol. 6g (bolts and screws) Internal thread tol. 6H (nuts) minor dia area π 2 π (d2 + d)2 diameter major diameter pitch diameter minor diameter pitch diameter minor diameter /4 d /4 2 A d A D s min = B P d max d max D min D max mm 2 mm 2 6 0,,8,88,4,,08 4,2,,64,88,8 20,2 22,0 8,4,4,24,22 6,4 6,6,0,00 6,, 6,0,2 0,4,4,24,22 8,4 8,6,0,00 8,, 60,4 64, 0,2,2,60,60,042 8,48 8,22,88,48 8,64 8,2 6,2 6,2 2,4,4,24,206 0,4 0,0,0,0 0,,, 6, 2,2,2,60,60,028 0,48 0,28,88,68 0,64 0,2 86,0 2, 2,,68,2 0,4 0,84 0,28,0,026,26 0,6 0,66 8,0 88, 4,,68,2 2,4 2,84 2,28,0,026,26 2,6 2,66 6, 2 6,,68,2 4,4 4,84 4,28,0,026,26 4,6 4,66, 6 8,,68,2 6,4 6,84 6,28,0,026,26 6,6 6,66 20, ,62,682 6,66 6,0,08,2 6,0 6,,8 6,20 8, ,,68,2 8,4 8,84 8,28,0,026,26 8,6 8,66 2, ,62,682 8,66 8,0,08,2 8,0 8,,8 8,20 24, , 2,68 2,2 20,4 20,84 20,28,0 2,026 2,26 20,6 20,66, ,62 2,682 20,66 20,0,08,2 20,0 20,,8 20,20 00, 8 24, 2,68 2,2 22,4 22,844 22,28 2,20 2,026 2,226 22,6 22,66 8, ,62 2,682 22,66 22,4 2,08 2,26 22,0 22,2 2,8 22,20 64,6 84 2, 26,68 26,2 2,4 2,844 2,28 24,20 26,026 26,226 2,6 2,66 4, ,62 26,682 2,66 2,4 24,08 24,26 2,0 2,2 24,8 2,20 4,2 46 0, 2,68 2,2 28,4 28,844 28,28 2,20 2,026 2,226 28,6 28,66 622, ,62 2,682 28,66 28,4 2,08 2,26 28,0 28,2 2,8 28,20 6,0 62, 2,68 2,2,4,844,28 0,20 2,026 2,226,6,66 62, ,62 2,682,6,4 0,08 0,26,0,2 0,8,20 2,8 6 6,,68,2 4,4 4,844 4,28,20,026,226 4,6 4,66 6, 40 6,2, 4,00,80 2,2, 4,0 4,6 2,2,22 820,4 86, 8,68 8,2,4,844,28 6,20 8,026 8,226,6, ,2 8,,00 6,80,2 4,,0,6,2 6,22, , 4,68 4,2 40,4 40,844 40,28,20 4,026 4,226 40,6 40, ,2 4, 40,00,80 8,2, 40,0 40,6 8,2, , 44,68 44,2 4,4 4,844 4,28 42,20 44,026 44,226 4,6 4, ,2 44, 4,00 42,80 4,26 40, 4,0 4,6 4,2 42, , 4,68 4,2 46,4 46,84 46,28 4,0 4,026 4,28 46,6 46, ,2 4, 46,00 4, 44,2 4,4 46,0 46, 44,2 4, ,,68,2 0,4 0,84 0,28 4,0,026,28 0,6 0, ,2, 0,00 4, 48,2 4,4 0,0 0, 48,2 4, ,62,682 4,66 4,48,08,2 4,0 4,,8 4, ,40,46,42,06,0 0,64,402,,60 2, ,40,46,42,06,0 4,64,402,,60 6, ,40 6,46 6,42 6,06,0 8,64 6,402 6,,60 60, ,40 6,46 6,42 6,06 6,0 62,64 6,402 6, 6,60 64, ,20,20 68,02 6,4 64, 64,048 68,0 68,48 6,0 66, ,20,20 2,02,4 68, 68,048 2,0 2,48 6,0 0, ,20,20 6,02,4 2, 2,048 6,0 6,48,0 4, ,20 8,20 86,02 8,4 82, 82,048 86,0 86,48 8,0 84, ,20,20 6,02,2 2, 2,028 6,0 6,0,0 4, ,20 0,20 06,02 0,2 02, 02,028 06,0 06,0 0,0 04, For coated threads the maximum values of d, and d are equal to the values of the basic profile (d2 max = and d max =D min ) Metric screw thread, fine series, are designated by the basic diameter, preceded by the profile letter M and followed by the pitch separated by an x-mark and then by the tolerance grade, e.g. 6, and the tolerance position, e.g. H. Example: M0 x,2 6H. If no tolerance is indicated the fit 6H/6g is valid T-00 The bold lines indicate the maximum material profiles. The maximum material profile of the is the basic profile. B = basic major diameter d = major diameter d D = major diameter D 2 D

3 ISO DIN Fine versus coarse thread The general trend for commercial fasteners over the past 20 years has shown a gradual and noticeable shifting in popularity toward coarse threads. And rightly so, as fine threads cannot be said to be technically superior. Altough fine threads are used in special cases, (such as for adjustment, or for certain engine screws), these cases occur so seldom that fasteners with fine thread are becoming more and more a special product with all the economic disadvantages (higher price, poor availability, double stocking). The fine screw thread is mainly created for and is still popular in, the automotive industry - and other related industries. The most important arguments of proponents of fine thread are: a higher static tensile strength because of its larger stress area. because of the smaller helix angle it offers more resistance to loosening when subjected to vibration. better accuracy of adjustment. In practice however most constructions are not charged statically but dynamically, so fatigue strength is the criterion. Coarse thread exhibits a better fatigue resistance because stress concentration at the root decreases as thread pith increases. The argument of better resistance to loosening has been outdated by the development of mechanical and chemical locking systems, which offer a more effective solution for loss of pre-tension especially during dynamic transversal forces. Further advantages of coarse thread are: less sensitive to damaging and generally easier and quicker assembly thicker coatings as a consequence of the larger thread allowances less danger of stripping off. The most important pros and cons can be summarised in the following evaluation table: Functional Screw thread properties coarse fine Strength static - + dynamic + - Locking without locking systems - + with locking systems Insentivity to damaging + - Coating thickness + - Stripping off + - Ease of assembly + - Cost and availibility + - COARSE THREAD is recommended for standardized fasteners in general constructions + means better or more favourable Note: For the conversion from the imperial to the metric system in the U.S.A. the Industrial Fasteners Institute has issued the handbook "Metric Fasteners Standards". In this book all threaded fasteners have only the COARSE thread series as standard. Changing from UNF to metric-fine is not recommended for commercial fasteners. 0 --

4 ISO DIN : Part Metric (ISO) screw thread with tolerance class Sk6 at the metal end of studs DIN T-004 The bold line indicates the minimum material profile d = major diameter = basic diameter d Limits of sizes for metric screw thread with tolerance class Sk6 Basic Pitch External thread (studs) diameter major diameter pitch diameter minor diameter d P d max d max 6 6,6,406, 4, 4,66 ()* 6,6 6,406 6,,,66 8,2 8,0,244, 6,466 6,4 ()*,2 8,0 8,244 8,,466,4 0, 0,20,082,0 8,60 8,0 ()*, 0,20 0,082 0,0,60,0 2, 2,600 0,4 0,84,8, ,2 2,8 2,68,46, ,2 4,8 4,68,46,6 8 2, 8,40 6,46 6,6 4, 4, 20 2, 20,40 8,46 8,6 6, 6, 22 2, 22 2,40 20,46 20,6 8, 8, ,400 22, 22,0 20, 20,08 Designation of this screw thread e.g. M2 Sk6. * Preferably not to be used. Remark: Tolerance class Sk6 is used for general applications e.g. studs (not sealed connection) and in combination with internal thread, tolerance class fine (4H resp. 4HH). These tolerance classes have to do with a transition fit, so a press fit will not always be achieved. Note: In the meantime a real press fit of metric screwthread (MFS) has been developed, which is achieved by an oversize on the major diameter. For the tolerances of this screwthread is referred to DIN 84 Part and for the corresponding gauges to DIN 84 Part 2. These standards can only be used for application in aluminium cast alloys and for sizes M up to and including M 6. Futher development depends on obtained experience. STANDARD ISO DIN : 20 Part 2 Metric screw thread with large clearance for double end studs with reduced shank DIN 20 T-00 R = root radius d = major diameter = basic diameter d --4 Basic profile and limits of sizes Basic Pitch Root- External thread (double studs with reduced shank) diameter radius major diameter pitch diameter pitch clear- minor diameter section at d P R d max ance min. d max minor dia. M 2, 0,8,82,8 0,686 0,6 0,,66,400 6 M 6 2 0,20,82,4 4,24 4,64 0,,6,06 M 20 2, 0,2,800,46 8,6 8,006 0,200 6, 6,8 20 M 24 0,0 2,88 2,4 2,8 2,6 0,22 20,0,6 0 M 2 0,0 26,88 26,4 24,8 24,6 0,22 2,0 22,6 40 M 0, 0, 2, 2,0 2,02 2,20 0,22 2,48 2,0 40 Designation of this screw thread e.g. M 6 DIN 20 0

5 ISO : 20 DIN : 0 Part and Metric (ISO) trapezoidal screw thread -Trfor threaded rods and nuts T-006 The bold lines indicate the maximum material profiles. The extra thick line is the basic profile. d = major diameter d D = major diameter D 2 D Limits of sizes for trapezoidal thread, medium pitch series, fit H/e External thread tol. e (threaded rods) Internal thread tol. H (nuts) Pitch Designation major diameter pitch diameter minor diameter major pitch diameter minor diameter P diameter d max d max D min D min D max Tr 0x2 2 0,000,820 8,2 8,,00, 0,00,000,20 8,000 8,26 Tr 2x 2,000,64 0,4 0, 8,00 8, 2,00 0,00 0,800,000, Tr 4x 4,000,64 2,4 2, 0,00 0, 4,00 2,00 2,800,000, Tr 6x4 4 6,000,00,0,640,00,04 6,00 4,000 4, 2,000 2, Tr 8x4 4 8,000,00,0,640,00,04 8,00 6,000 6, 4,000 4, Tr 20x4 4 20,000,00,0,640,00,04 20,00 8,000 8, 6,000 6, Tr 22x 22,000 2,66,4,4 6,00 6,044 22,00,00,8,000,40 Tr 24x 24,000 2,66 2,4 2,04 8,00 8,0 24,00 2,00 2,00,000,40 Tr 26x 26,000 2,66 2,4 2,04 20,00 20,0 26,00 2,00 2,00 2,000 2,40 Tr 28x 28,000 2,66 2,4 2,04 22,00 22,0 28,00 2,00 2,00 2,000 2,40 Tr 0x6 6 0,000 2,62 26,882 26,4 2,000 22,46,000 2,000 2,40 24,000 24,00 Tr 2x6 6 2,000,62 28,882 28,4 2,000 24,46,000 2,000 2,40 26,000 26,00 Tr 6x6 6 6,000,62 2,882 2,4 2,000 28,46,000,000,40 0,000 0,00 Tr 40x 40,000, 6, 6,020 2,000,4 4,000 6,00 6,,000,60 Tr 44x 44,000 4, 40, 40,020 6,000,4 4,000 40,00 40,,000,60 Tr 0x8 8 0,000 4,0 4,868 4,468 4,000 40,68,000 46,000 46,0 42,000 42,60 Tr 60x 60,000,00,60 4, 0,000 4,2 6,000,00 6,060,000,60 This trapezoidal screw thread is recommended for general use and does not apply to special requirements for axial displacement, e.g. lead screws. The diameter/pitch combination medium only refers to the choice out of the series coarse, medium or fine and not to the quality of the screw thread or the tolerance class. This trapezoidal screw thread is designated with the profile letters Tr, followed by the basic diameter and the pitch separated by a X-mark e.g. Tr 20x

6 ISO : 864 DIN ANSI : B. Unified (ISO) screw thread - UNC, UNF and 8UN - T-00 The bold lines indicate the maximum material profiles. The maximum material profile of the is the basic profile. B = basic major diameter n = number of threads per inch d = major diameter D = major diameter D 2 internal diameter d D Section at Stress Basic Number External thread tol. 2A (bolts and screws) Internal thread tol. 2B (nuts) minor dia. area diameter of major threads Pitch major diameter pitch diameter minor diameter diameter pitch diameter minor diameter π 2 /4 d π (d2 + d)2 /4 2 B A d A n P s dmax d max D min D min D inch max mm 2 mm 2 Limits of sizes for unified screw thread: coarse-unc, tolerance classes 2A anb /4 20,200 6,22 6,,46,40 4,6 4,80 6,0,2,646 4,,2,4 20, /6 8,4,0,68 6,0 6,88 6,4,2,8,02, 6,40 6, 2,,8 /8 6,8,4,24 8,460 8,4,4,8,2 8,44 8,68,8 8, 4, 0 /6 4,84,06 0,86,88, 8,8 8,60,,4 0,088,44,0 60,2 68,6 /2,8 2,66 2,86,,26 0,264,8 2,00,40, 0,2,02 8,, /6 2 2,6 4,246,8 2,82 2,4,60,6 4,288 2,4,086,8 2,446 0,4 /8 2,0,84,28 4, 4,,002 2,68,8 4, 4,,86, /4 0 2,400,004 8,6,,204,88,,00,,4 6,0 6,840 2 /8 2, ,6 2,824 20,42 20,8 8,4 8,2 22,22 20,2 20,,, ,0 2,4 24,6 2,286 2,4 2,42 2,02 2,400 2,8 2,6 2, 22,606 /8, , 28,0 26,62 2,80 24,066 2,62 28, 26,28 26,46 24,68 2, /4,6286,64,28 2, 2,0 2,24 26,2,0 2, 2,66 2,8 28, /8 6 4,2 4,864 4,402 2,, 2,66 2,62 4,2 2, 2,48 0,, /2 6 4,2 8,0,,288,08 2,844 2, 8,00,0,6,28 4, /4, ,8 4,86 4,08 40,86 8,48, 44,40 4, 4,44 8,64, /2,6444 0,26 0,68 4,06 46,820 4,802 4, 0,800 4, 4,44 44,6 4, /4 4 /2,6444,06 6,8,4,6 0,2 4,00,0,48,804,02, /2 4 6,00 6,42 62,8,26,0,6 4,0 6,00,6, 6,6, /4 4 6,00 6,68 6,6 6,64 6,8 6,8 6,2 6,80 6,26 66,0 62,6 6, ,00 6,8,,,22 68,28 6,600 6,200 2,06 2,428 6, 0, Limits of sizes for unified screw thread: fine-unf, tolerance classes 2A anb /4 28 0,0 6,24 6,60,,62,22,06 6,0,6,86,60,88 2,0 2, /6 24,08,0,2,22,28 6,6 6,442,8,20, 6,82,0,8,4 /8 24,08,4, 8,808 8, 8, 8,02,2 8,8 8,6 8,82 8,66 2,2 6,6 /6 20,200,0 0,84 0,2 0,48,22,2, 0,28 0,424,2 0,0 0, 6,6 /2 20,200 2,666 2,462,84,,0 0,0 2,00,8 2,06,2,60, 0 /6 8,4 4,2 4,0,,22 2, 2,04 4,288,,20 2,,08 22 /8 8,4,8,6 4,22 4,804 4,0,88,8 4,,0 4, 4,68 6 /4 6,8,0 8,4,80,84,06 6,82,00 8,0 8,8,2, /8 4,84 22,84 2,2 2,00 20,86,,6 22,22 2,04 2,224 20,20 20, ,6 2,4 2,06 2,80 2,8 22,8 22,4 2,400 24,026 24,28 2,4 2, ,84 2, 2,0 24,8 24,06 2,2 2,400 24,22 24,40 2,444 2, /8 2 2,6 28,2 28,240 2, 2,00 2, 2,62 28, 2,20 2,8 26,28 26, /4 2 2,6,04,4 0,0 0, 2,08 28,,0 0,6 0, 2,464 2, /8 2 2,6 4,86 4,88,02,4 2,280,6 4,2,, 2,6, /2 2 2,6 8,0,6 6,6 6,6,4,4 8,00 6,26 6,6,84 6, Limits of sizes for unified screw thread: 8 UN, tolerance classes 2A anb nom. /8 8,0 28,2 28,4 26,4 26,284 24,6 28, 26, 26,4 2,46 2, /4 8,0,6,6 2,64 2,46 2,800,0 2,688 2,2 28,2 28,6 64 /8 8,0 4,86 4,488 2,80 2,624 0, 4,2 2,86,0,46 2, 4 / 2 /8 8 8,0,0 8,044 4,2,66 40,88,82,,6 8,6 4,48,2 8,00 4,2 6,08,2 6,2,4 4,6,846,06 8, /4 8,0 44,2 44,0 4,2 42, 40,4 44,40 42,88 42,66 4,02 4, /8 8,0 4,6 4,86 4,64 4,0 4,60 4,62 4,6 4,8 44,6 44, ,0 0,42 0,6 48,6 48,48 46,84 0,800 48,8 48,4 4, 48, For coated threads the maximum values of d, en d are equal to the values of the basic profile ( = en d max =D min ). Unified screw thread is designated by the basic diameter followed by the number of threads per inch (n), the thread series UNC, UNF or 8 UN and the tolerance class. e.g.: /8-24 UNF - 2A. When no tolerance class is mentioned, the fit 2A/2B is valid

7 ISO DIN USAS : B. Unified number threads - UNC and UNF - T-008 The bold lines indicate the maximum material profiles. The maximum material profile of the is the basic profile. B = basic major diameter n = number of threads per inch B = major diameter d = major diameter D = major diameter D 2 d D Limits of sizes for UNC en UNF-number thread, tolerance class 2A en 2B External thread - tol. 2A (screws) Internal thread - tol. 2B (nuts) designation B n P major diameter pitch diameter minor diameter pitch diameter minor diameter d max d max D min D max 4-40 UNC 2, ,6 2,824 2,6 2,4 2,0 2,044 2,44 2, 2, 2,8-40 UNC, 40 0,6,4,026 2,4 2,68 2,4 2,64 2,84 2,48 2,6 6-2 UNC,0 2 0,4,484, 2,6 2,8 2,2 2,0,08 2,642 2,8 8-2 UNC 4,6 2 0,4 4,42,,62,4,6,60,46,02, UNC 4,826 24,08 4,800 4,68 4,2 4,02,02 4,8 4,246,68, UNC,486 24,08,46,2 4,2 4,68 4,6 4, 4,0 4,44 4, 4-48 UNF 2, ,2 2,82 2, 2,484 2,424 2,6 2,02 2,80 2,2 2,48-44 UNF, 44 0,,,06 2,8 2,8 2,448 2,800 2,880 2, 2, UNF,0 40 0,6,484,6,0,008 2,0,04,80 2,820, UNF 4,6 6 0,06 4,4 4,006,688,6,2,0,,404, UNF 4, ,4 4,80 4,6 4,28 4,22,80 4, 4,40,6 4, UNF, ,0,46,26 4,8 4, 4,48 4,88,00 4,46 4,24 STANDARD ISO DIN BS : () BA-screw thread T-00s d = major diameter d D = major diameter D 2 D Limits of sizes for BA-screw thread, tolerance class normal External thread (screws) Internal thread (nuts) designation P major diameter pitch diameter minor diameter major diameter pitch diameter minor diameter d max d max D min D min D max 0 BA,00,,,,20 4, 4,2 6,000,400,0 4,800, BA 0,0,2,0 4, 4,620 4,,6,00 4,60 4,00 4,220 4,60 2 BA 0,8 4,6 4, 4,0 4,08,0,4 4,00 4,2 4,40,0 4,0 BA 0, 4,0,0,6,,,000 4,00,660,80,220,4 4 BA 0,66,,44,80,00 2,8 2,60,600,20, 2,80,060 BA 0,,,0 2,820 2, 2,46 2,2,200 2,84 2,4 2,40 2,0 6 BA 0, 2, 2,60 2,4 2, 2,,80 2,800 2,480 2, 2,60 2,60 BA 0,48 2,4 2,80 2,8 2,0,8,0 2,00 2,20 2,00,20 2,00 8 BA 0,4 2, 2,00,,84,6,20 2,200,40 2,020,680,

8 ISO DIN BS : (0) w : 84 (6) WHITWORTH SCREW THREAD IS OUTDATED! This screw thread is not recommended internationally and for new constructions is advised to use the metric (ISO) or the unified (ISO) screw thread. Whitworth screw thread - BSW and BSF - T-00 The bold line indicates the maximum material profile. B = basic major diameter n = number of threads per inch d = major diameter D = major diameter D 2 d D Limits of sizes for whitworth screw thread coarse-bsw, medium class Basic number (bolts and screws) (nuts) Section at. minor dia. diameter of pitch threads major diameter pitch diameter minor diameter major pitch diameter minor diameter π 2 /4 d diameter B A n P d d inch max max min d max d min D min =B D 2 min D 2 max D min D max mm 2 /8 40 0,6,,0 2,6 2,68 2,62 2,202, 2,6 2,84 2,82 2,622 4, /2 2 0,4,4,84,46, 2, 2,,6,46, 2,,24 6,8 /6 24,08 4,4 4,8 4,084,80,406,8 4,6 4,084 4,88,426,8,0 /4 20,20 6,0 6,000,,424 4,24 4,422 6,0,,60 4,44,224, /6 8,4,8,600,04 6, 6,,8,8,04, 6, 6,66 2,48 /8 6,88,0,00 8,0 8,82,42,4,2 8,0 8,66,2 8,02 44,06 /6 4,84,0 0,00,,86 8,8 8,40,, 0,086 8,80, 60, /2 2 2, 2,6 2,200,4,,0,600 2,00,4,4 0,0 0,60 8,2 /6 2 2, 4,26,800 2, 2,8,8,88 4,288 2,,0,60 2,8 0 /8 2,0,846,400 4, 4,244 2,8 2,0,86 4, 4,0 2,48,8 /6 2,0,4,000,8,82 4,0 4,0,46,8 6,8 4,,8 6 /4 0 2,40,08 8,00,424,264,8,,0,424,84,8 6,8 6 /8 2,822 22,0 2,600 20,4 20,20 8,6 8,6 22,226 20,4 20,88 8,64,4 22 8, 2,6 24,800 2,68 2,8 2, 20,88 2,40 2,68 2,4 2, 22,8 8 /8,62 28,2 2,00 26,2 26,062 2,2 2,4 28,6 26,2 26,444 2,6 24,8 40 /4,62,04,000 2,428 2,2 2,04 26,4, 2,428 2,6 2, 28,04 /2 6 4,2 8,048,00,,84 2,680 2,28 8,0,,8 2,,0 8 /4,080 44,8 4,00 4, 40,2,46,4 44,42 4, 4,426 8,00,06 2 4,,64 0,2 4,800 4,8 46,48 4, 42,6 0,802 4,8 4,426 4,64 44, /4 4 6,0,02 6,200,086 2,8 4,020 48,4,2,086, 4,00 0, /2 4 6,0 6,422 62,00,46,8,0 4,6 6,02,46,68,40 6, /4,,2 6,6 68,800 6,20 64,4 60,8,86 6,8 6,20 6,46 60,648 62, ,,2 6,,00,6,28 66,0 66,8 6,20,6,82 66, 68,4 Limits of sizes for whitworth screw thread fine-bsf, medium class for and normal class for /4 26 0, 6,22 6,,6,60,02 4,8 6,0,2,86,00,8 20,4 /2 26 0,,2 6,62 6,48 6,88,862,664,42 6,8 6,66,8 6,0 2,2 /6 22,,0,0,68,064 6,42 6,2,8,8,6 6,4 6,8 2, /8 20,20,42,24 8,6 8,6,866,640,2 8,2 8,880,8 8, 4,0 /6 8,4,0 0,8 0, 0,0,268,00, 0,208 0,86,04,64 68,00 /2 6,88 2,662 2,4,646, 0,60 0,6 2,00,684,82 0,668,6 8, /6 6,88 4,24 4,04,2,0 2,2,8 4,288,22,46 2,26 2, 8 /8 4,84,84,62 4,64 4,6,,24,8 4,4 4,20, 4,04 44 /6 4,84,4,20 6,2 6,6,08 4,82,46 6,02 6,,4, /4 2 2,,004 8,8,648,48 6,22,4,00,64, 6,8 6, 20 /8 2,0 22,22 2, 20,4 20,8,268 8, 22,22 20,4 20,8,268, ,40 2,400 2, 2,4 2,60 22,4 2,82 2,400 2,4 24,026 22,4 22,8 8 After applying a corrosion resistant coating the maximum limits of sizes of the may not exceed the minimum limits of sizes of the. Whitworth screw thread is designated by the basic diameter in inches followed by the number of threads per inch (n), the thread series BSW or BSF and if desired the class of tolerances. Where the latter is not indicated, the above mentioned classes are applicable e.g. / 4-20 BSW or / 2-6 BSF

9 ISO : 48 : 248 DIN : 0 Tapping screw thread-st for tapping and self drilling screws screw thread ST thread ends T-0 T-02 slight radius type C cone end (previous ISO-type AB, DIN-type B) type F flat end (previous ISO-type B, DIN-type BZ) thread profile Limits of sizes for tapping screw thread Basic ISO Pitch Major diameter Minor diameter Flat end diameter Crest flattening Point taper length ymax Diameter Nr. P d max d max c max Type C Type F ST 2,2 2 0,8 2,24 2,,6,2,4, 0, 2,6 ST 2,6 0, 2, 2,4,,8,,6 0, 2,,8 ST 2, 4, 2, 2,6 2,8 2,08 2,0,88 0, 2,6 2, ST,,,,2 2, 2,2 2,2 2,08 0, 2, ST, 6,,, 2,64 2, 2,4 2,26 0,,2 2, ST,,,, 2,2 2, 2,6 2, 0,, 2, ST 4,2 8,4 4,22 4,04, 2, 2,84 2,6 0,, 2,8 ST 4,8 0,6 4,8 4,62,8,4,,2 0, 4,,2 ST, 2,8,46,28 4,,,86,68 0,,6 ST 6, 4,8 6,2 6,0 4,88 4, 4, 4,4 0, 6,6 It has been agreed internationally that tapping screw thread is designated by the basic diameter, preceded by the profile letters ST and that the thread end with cone end is indicated with type C and the thread end with flat end with type F, e.g.: ST,-C. For core holes see table elsewhere in this section. STANDARD ISO DIN : 8 Wood screw thread for wood screws T-0 thread end at the option of the manufacturer Basic diameter Pitch Minor diameter d tol. h P tolerance d tol. h,6 0, ± 0,0, 2 0, ± 0,0,4 2,, ± 0,,, ± 0,4 2,,,6 ± 0,6 2,4 4,8 ± 0,8 2,8 4, 2 ± 0,2, 2,2 ± 0,22, (,) 2,4 ± 0,24,8 6 2,6 ± 0,26 4,2 (),2 ± 0,2 4, 8,6 ± 0,6,6 0 4, ± 0,4 2 ± 0, 6 6 ± 0, ± 0, Wood screw thread is designated by the basic diameter e.g. 4 mm:

10 ISO DIN : 8 Metric-fine tapered external screw thread for pipe plugs DIN 06 T-04 T-0 External thread Axis screw thread taper : 6 gauging plane gauging plane Metric-fine tapered external screw thread is intended to be used for tight joints like pipe plugs, lubricating nipples, etc. Up to and including M26 no jointing medium is required for oils, other liquids and gases; above an appropriate pressure, tight medium is recommended. The tapered is normally combined with parallel according to DIN 8. The metric-fine tapered is designated by the basic diameter, preceded by the profile letter M and followed by the pitch, separated by an X-mark e.g.: M 20x,. Limits of sizes for tapered, short type External thread gauge useful Designation Pitch major diameter pitch diameter minor diameter length thread length P d max d max b l M 8x 8,0 8,0,44,8 6,866 6,806 4 M 0x M 2x,, 0,0 2,2 0,0 2,4,44,26,8,6 8,866 0, 8,806 0,0, 4, M 4x,, 4,2 4,4,26,6 2, 2,0,, M 6x, M 8x,,, 6,2 8,2 6,4 8,4,26,26,6,6 4, 6, 4,0 6,0,,,, M 20x,, 20,2 20,4,26,6 8, 8,0,, M 22x, M 24x,,, 22,2 24,2 22,4 24,4 2,26 2,26 2,6 2,6 20, 22, 20,0 22,0,,,, M 0x,, 0,2 0,4 2,26 2,6 28, 28,0,, M 6x, M 42x,,, 6,282 42,282 6,6 42,6,06 4,08,82 4,82 4,442 40,442 4,6 40,6 6, 6, STANDARD ISO DIN : 88 Whitworth tapered external pipe thread-r for pipe plugs DIN 06 T-06 T-0 gauging plane Axis screw thread taper : 6 gauging plane Useful thread length (at least l The Whitworth tapered external pipe thread is designated by the profile letter R followed by the nominal diameter in inches e.g.: R / Nominal sizes for tapered with tolerance 2 and short type a. External thread Designation Number of major pitch minor Gauge Useful threads Pitch diameter diameter diameter length thread length n P d d a l R /8 28 0,0,28,4 8,66, R /4,, 2,0,44 4, 8,2 R /8, 6,662,806 4,0 4, 8,2 R /2 4,84 20,, 8,6 0,0 R /4 4,84 26,44 2,2 24, 6,0 R 2,0,24,0 0,2,4 R /4 2,0 4,0 40,4 8,2,, R /2 2,0 4,80 46,24 44,84,,

11 ISO : 228 Part DIN ISO : 228 part Pipe threads - G, parallel, non pressure-tight T-08 basic profile The bold line indicates the basic profile n = number of threads per inch d = major diameter d2 d D = major diameter D2 D Limits of sizes for parallel external pipe threads - G External thread, class of tolerance A number of pitch Internal thread Designation Major diameter Pitch diameter minor diameter threads Designation major diameter pitch diameter minor diameter d max.. d2 max. d2 min. d nom. n p D nom. D2 max. D2 min. D max. D min. G /8 A,28,4,4,040 8, ,0 G /8,28,24,4 8,848 8,66 G /4 A, 2,0 2,0 2,6,44, G /4, 2,426 2,0,80,44 G /8 A 6,662 6,42,806,68 4,0, G /8 6,662,,806, 4,0 G /2 A 20, 20,6,,6 8,6 4,84 G /2 20,,,,2 8,6 G /8 A 22, 22,62 2,4 2,60 20,8 4,84 G /8 22, 2,8 2,4 2,28 20,8 G /4 A 26,44 26, 2,2 2, 24, 4,84 G /4 26,44 2,42 2,2 24,68 24, G /8 A 0,20 2, 2,0 28,8 2,8 4,84 G /8 0,20 2,8 2,0 28,48 2,8 G A,24 2,8,0,0 0,2 2,0 G,24,0,0 0, 0,2 G /8 A,8, 6,48 6,28 4, 2,0 G /8,8 6,8 6,48, 4, G /4 A 4,0 4,0 40,4 40,2 8,2 2,0 G /4 4,0 40,6 40,4,2 8,2 G /2 A 4,80 4,44 46,24 46,44 44,84 2,0 G /2 4,80 46,04 46,24 4,48 44,84 Parallel pipe threads - G are intended for the mechanical assembly of the component parts of fittings, cocks and valves, accessories, etc., where pressure-tight joints are not made on the threads. These threads are designated by the letter G, followed by the nominal size in inches and for followed by the letter A or B of the class of tolerance. Example: for G /2 A and for G /