V-belt pulley grooves ISO 4183: SPZ, SPA, SPB, SPC datum width, groove spacing, angle and minimum diameter — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/v-belt-pulley-grooves-iso-4183-narrow/  (sheet CC BY 4.0)
Basis: ISO 4183:1995 sample pages (datum widths, spacing, angles, minimum diameters) and the Miskolc pulley table; disagreements shown; partial by design
Catalog version: 2026-10-20

Sizes: see table below
- ISO 4183 defines pulley grooves for classical (Y, Z, A, B, C, D, E) and narrow (SPZ, SPA, SPB, SPC) V-belts by the datum width wd, the groove width at the datum line where the belt's effective (pitch) line sits. Datum widths: Y 5.3, Z 8.5, A 11, B 14, C 19, D 27, E 32 mm; the narrow profiles SPZ / SPA / SPB / SPC use 8.5 / 11 / 14 / 19. Allowed groove angles are 32°, 34°, 36°, 38° (± 0.5°); the narrow profiles use 34° on small and 38° on large datum diameters.
- Where the two sources agree: datum widths; groove spacing e = 12, 15, 19, 25.5 mm for SPZ / SPA / SPB / SPC (the ISO 4183 sample shows 12 / 15 / 19 / 25,5 and the Miskolc table 12 / 15 / 19 / 255, a misprint of 25.5 that is read as 25.5 here); angle breaks 80 / 118 / 190 / 315 mm (Miskolc lists them directly: 34° for P up to the value, 38° above; the ISO sample shows the 118 / 190 / 315 breaks); the minimum datum diameters 63 / 90 / 140 / 224 mm (ISO sample table; the profile order was read from the sequence).
- Where they differ or are single-source: the depth above the datum line b (Miskolc 2.0 / 2.8 / 3.5 / 4.8 against an ISO-sample reading of 2 / 2.75 / 3.15 / 4.8; shown in brackets where it differs); groove depth below the datum h (Miskolc only: 11 / 13.8 / 17.5 / 23.8 mm; the ISO sample shows 8.7 / 10.8 / 14.3 for the classical A / B / C, which share rows with SPA / SPB / SPC, so h must be taken from the standard or the maker before cutting). Edge distance f (Miskolc 8 / 10 / 12.5 / 17 mm; the ISO sample prints minimums of 7 / 9, 9 / 11, 11.5 and 16 for Z / SPZ, A / SPA, B / SPB and C / SPC), tolerances on e (± 0.3 / 0.4 / 0.5 mm) and the groove-surface finish were not tabulated.
- Left out: the RMA / MPTA IP-20 classical A / B and 3V / 5V (and 8V) sheave groove tables (groove angle 34° / 36° / 38° by outside diameter, depth, spacing): none of the readable sources gave the numbers legibly, so they are not in the table and no groove-gauge profile was drawn from the inch tables. The ISO 4183 numbers above are not enough for a groove gauge either (depth h conflicts), so no files.
- Sheave CAD: the groove profiles are in the standard (paid) and in the pulley makers' catalogues; QD and Taper-Lock bores are on the bushing pages.

groove profile  datum width wd, mm  groove spacing e, mm  groove angle by datum Ø dd, mm  min datum Ø dd, mm  groove depth above datum b, mm  groove depth below datum h, mm
SPZ  8.5  12  34° up to 80, 38° above  63  2  11 (Miskolc)
SPA  11  15  34° up to 118, 38° above  90  2.8 (ISO sample 2.75)  13.8 (Miskolc)
SPB  14  19  34° up to 190, 38° above  140  3.5 (ISO sample 3.15)  17.5 (Miskolc)
SPC  19  25.5  34° up to 315, 38° above  224  4.8  23.8 (Miskolc)

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- ISO (iTeh sample pages): ISO 4183:1995 Belt drives, classical and narrow V-belts, grooved pulleys (system based on datum width): datum widths, groove spacing, angles, minimum datum diameters — web — Publisher's page; dimensions are facts — https://cdn.standards.iteh.ai/samples/25817/ae47c2ed867549cbadc47a63b459cf35/ISO-4183-1995.pdf
- University of Miskolc (course material): Wedge-belt pulley table SPZ / SPA / SPB / SPC: belt and groove dimensions, 34° / 38° pitch-diameter limits — web — Publisher's page; dimensions are facts — https://web.uni-miskolc.hu/gepelemek/tantargyaink/004b_gepelemek2/oktatasi-segedanyag/1_rugalmas_hajtas_mellekletek4-ekszijtarcsak.pdf
- ISO: ISO 4183 Belt drives: classical and narrow V-belts, grooved pulleys (the standard itself, paid) — web — Publisher's page; dimensions are facts — https://standards.iteh.ai/catalog/standards/iso/a5169929-6125-4f88-a7fb-9dfd40907936/iso-4183-1995

No true-size file yet: the published figures do not fix the whole shape; a measured scan is planned.
API: https://xemstudio.com/api/geometry?object=v-belt-pulley-grooves-iso-4183-narrow