Spring Pin Size Chart — ISO 8752 / 13337 / 8748 / 8750 / 8751 (GB/T 879.1–879.5), Slotted & Coiled

One row per part: standard, construction group, load class, number of d1 sizes and their range, number of lc length steps and their range, and the shear-load convention. d2 = slot root diameter (before insertion); a = slot width; s = pin wall thickness. All figures come from Table 1 of the respective part and match the per-part pages cell for cell.

Basis & Disclosed Assumptions

Where the numbers come from

• Every dimension and shear value comes from Table 1 and the lc sub-table below Table 1 of the five parts (GB/T 879.1 slotted heavy duty, 879.2 slotted light duty, 879.3 coiled heavy duty, 879.4 coiled standard duty, 879.5 coiled light duty). This page and the per-part pages share one constant, so every cell can be recalculated.
• d1 max, d1 min and d2 are all pre-insertion values (the standard's own heading word): the pin is larger than the hole before it is pressed in and holds by elastic recovery, so the limit sizes sit above the nominal value.
• Shear load is the minimum double shear load in kN. ISO 8752 / GB/T 879.1 and ISO 13337 / GB/T 879.2 give a single row (steel and martensitic stainless) and state in a table note that no double shear load is specified for austenitic stainless spring pins; ISO 8748 / GB/T 879.3, 879.4 and 879.5 give a and b rows (a = steel and martensitic stainless, b = austenitic stainless). Steps left unspecified by the standard are blank in the tables below.
• The d1 and lc steps are not interchangeable between parts: this index lists each part's own size count and range, and the same nominal diameter d1 carries a different wall thickness s and load capacity in each part.

Scope & limits

• The nominal hole diameter is the nominal pin diameter d1 with tolerance zone H12 (ISO 286-2 / GB/T 1800.2). The one exception is ISO 8750 / GB/T 879.4: H12 for d1 ≥ 1.5 mm and H10 for d1 ≤ 1.2 mm.
• Length limits are banded: ±0.25 mm for lc ≤ 10 mm, ±0.5 mm for 12–50 mm and ±0.75 mm for 55–200 mm; above 200 mm nominal length the series steps by 20 mm.
• The standard allows the pin to be fitted in the smallest permitted hole but requires that the slot must not close completely. Size the hole and fit against the actual duty; this chart only reports the nominal and limit sizes fixed by the standard.
• No weight or material-strength data here: the spring pin parts do not tabulate mass, and this site offers no weight calculator for this family.

Cite this chart

The other family in this group: cotter pins

Cotter pins and spring pins both retain inside a hole, but assembly, reusability and load data differ. A cotter pin is threaded through the hole and its legs are opened behind it, and it is normally not reused; a spring pin locks by radial spring force, can be removed and refitted many times, and carries a shear load quoted by its own standard. Use a cotter pin for shaft-end retention where the opened legs can be seen; use a spring pin for location duties, frequent disassembly or alternating lateral force.