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Trapezoidal lead screw threads Tr10 to Tr40 (ISO 2904 / DIN 103): Tr10x2, Tr12x3, Tr16x4, Tr20x4, Tr24x5, Tr30x6, Tr40x7: pitch, d2, D4, d3, D1

What are the pitch diameter, minor diameter and nut major diameter of a Tr10x2, Tr12x3, Tr16x4, Tr20x4, Tr24x5, Tr30x6 or Tr40x7 trapezoidal thread? · Standard part · basis: ISO 2904:2020 sample table (iTeh) with formula checks on every row; fasten.it, Roymech and AmesWeb as comparison; numbers only

Also called: Tr10x2 thread dimensions, Tr12x3 thread dimensions, Tr14x3 thread dimensions, Tr16x4 thread dimensions, Tr20x4 thread dimensions, Tr24x5 thread dimensions, Tr30x6 thread dimensions, Tr40x7 thread dimensions, Tr8x2 dimensions, Tr10x2 pitch diameter, Tr10x2 minor diameter, Tr12x3 minor diameter, Tr16x4 d3, Tr20x4 d2, Tr10x2 lead screw, Tr10x1.5 thread, trapezoidal thread chart, metric acme thread, D

Exact dimensions. True size, with no tolerance added.

sizes: 44 in table

Notes

Tr is the metric trapezoidal (30 degree flank angle) lead-screw thread: Tr10x2 means 10 mm nominal diameter and 2 mm pitch. For a single-start screw the lead equals the pitch; a multi-start thread has lead = P x starts and is written Tr d x lead (P pitch). The standard's formulas: D1 = d - P, d2 = D2 = d - 0.5 P, D4 = d + 2 ac, d3 = d - P - 2 ac (ac is the crest clearance, which differs by pitch).
Numbers: the ISO 2904:2020 sample (iTeh) table for Tr10 to Tr40 (44 d x P combinations); the generator re-checks D1 = d - P, d2 = d - 0.5 P and d3 = d - P - 2 ac on every row (ac = (D4 - d) / 2). AmesWeb's limits tables print the same screw minor and nut major values where compared (Tr10x1.5: d3 8.200, D4 10.300; Tr16x4: d3 11.500; Tr40x7: d3 32.000).
Disagreements kept: fasten.it's copy of the table (a cancelled-DIN reproduction) prints Tr10x1.5 with D4 11, d3 8 and D1 7.5, Roymech with D4 11, d3 2.000 and D1 3.000; the ISO 2904 sample and AmesWeb both give D4 10.3, d3 8.2, D1 8.5, which the formulas confirm. fasten.it, Roymech and AmesWeb also list Tr16x3 (and Tr18x3, Tr20x3 on AmesWeb), which the ISO 2904 sample table does not; Tr16x4 is in the ISO sample (and AmesWeb) but fasten.it and Roymech print Tr16x3 in its place. Those rows are not used here.
Numbers only, no files: a lead screw's length, ends and start count are chosen by the user, and the helical thread is not a published envelope. For modelled lead screws see the T8 lead screw and the Tr10x2 screw pages.
Left out: the external / internal tolerance classes (7e, 7H and so on), the multi-start leads, Tr sizes above 40 mm, ac / H4 / h3 values per pitch (not in the sample).

Trapezoidal lead screw threads Tr10 to Tr40 (ISO 2904 / DIN 103)… size chart

thread	nominal Ø d, mm	pitch P, mm	pitch Ø d2 = D2, mm	nut major Ø D4, mm	screw minor Ø d3, mm	nut minor Ø D1, mm
Tr10x1.5	10	1.5	9.250	10.300	8.200	8.500
Tr10x2	10	2	9.000	10.500	7.500	8.000
Tr11x2	11	2	10.000	11.500	8.500	9.000
Tr11x3	11	3	9.500	11.500	7.500	8.000
Tr12x2	12	2	11.000	12.500	9.500	10.000
Tr12x3	12	3	10.500	12.500	8.500	9.000
Tr14x2	14	2	13.000	14.500	11.500	12.000
Tr14x3	14	3	12.500	14.500	10.500	11.000
Tr16x2	16	2	15.000	16.500	13.500	14.000
Tr16x4	16	4	14.000	16.500	11.500	12.000
Tr18x2	18	2	17.000	18.500	15.500	16.000
Tr18x4	18	4	16.000	18.500	13.500	14.000
Tr20x2	20	2	19.000	20.500	17.500	18.000
Tr20x4	20	4	18.000	20.500	15.500	16.000
Tr22x3	22	3	20.500	22.500	18.500	19.000
Tr22x5	22	5	19.500	22.500	16.500	17.000
Tr22x8	22	8	18.000	23.000	13.000	14.000
Tr24x3	24	3	22.500	24.500	20.500	21.000
Tr24x5	24	5	21.500	24.500	18.500	19.000
Tr24x8	24	8	20.000	25.000	15.000	16.000
Tr26x3	26	3	24.500	26.500	22.500	23.000
Tr26x5	26	5	23.500	26.500	20.500	21.000
Tr26x8	26	8	22.000	27.000	17.000	18.000
Tr28x3	28	3	26.500	28.500	24.500	25.000
Tr28x5	28	5	25.500	28.500	22.500	23.000
Tr28x8	28	8	24.000	29.000	19.000	20.000
Tr30x3	30	3	28.500	30.500	26.500	27.000
Tr30x6	30	6	27.000	31.000	23.000	24.000
Tr30x10	30	10	25.000	31.000	19.000	20.000
Tr32x3	32	3	30.500	32.500	28.500	29.000
Tr32x6	32	6	29.000	33.000	25.000	26.000
Tr32x10	32	10	27.000	33.000	21.000	22.000
Tr34x3	34	3	32.500	34.500	30.500	31.000
Tr34x6	34	6	31.000	35.000	27.000	28.000
Tr34x10	34	10	29.000	35.000	23.000	24.000
Tr36x3	36	3	34.500	36.500	32.500	33.000
Tr36x6	36	6	33.000	37.000	29.000	30.000
Tr36x10	36	10	31.000	37.000	25.000	26.000
Tr38x3	38	3	36.500	38.500	34.500	35.000
Tr38x7	38	7	34.500	39.000	30.000	31.000
Tr38x10	38	10	33.000	39.000	27.000	28.000
Tr40x3	40	3	38.500	40.500	36.500	37.000
Tr40x7	40	7	36.500	41.000	32.000	33.000
Tr40x10	40	10	35.000	41.000	29.000	30.000

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

iTeh Standards	ISO 2904:2020 sample: ISO metric trapezoidal screw threads, basic dimensions, formulas and the d, P, d2, D4, d3, D1 table (Tr10 to Tr40)	web	Publisher's page; dimensions are facts
fasten.it	ISO 2904 (cancelled DIN 103 successor) trapezoidal thread table, reproduced by permission of DIN	web	Publisher's page; dimensions are facts
Roymech	Trapezoidal threads: metric table d, P, d2, D4, d3, D1	web	Publisher's page; dimensions are facts
AmesWeb	Trapezoidal thread chart: external / internal major, pitch, minor diameter limits	web	Publisher's page; dimensions are facts

Xem scan

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Plain text: sheet.txt · JSON: /api/geometry?object=trapezoidal-threads-tr10-tr40-iso-2904

Schematic, not to scale.