Free to use, provided as-is. No warranty or guarantee of accuracy or fitness for purpose. AbarTech Ltd accepts no liability for outcomes arising from use of these calculators.
Free Engineering Calculators
Retaining Ring & Circlip Design Calculators
Design retaining rings from first principles — calculate ring width, load capacity,
assembly stress, installation clearance and loosening speed. Covers all major
ring types from standard DIN 471/472 circlips to grooveless grip rings.
Eight calculator modules covering every common retaining ring type. Not sure which
to use? The decision guide below will point you to the right one.
Which Calculator Do I Need?
Answer the questions below to find the right module for your application.
1. Does your application allow a machined groove in the shaft or bore?
Recommended
Grip Ring — Module B
Retained by friction on a plain shaft. No groove required. Covers shaft diameters 1.5–30 mm. The retaining force depends strongly on shaft surface condition.
Standard DIN 471/472 retaining rings and variants (V-ring, K-ring, reinforced). The most common ring type — best load capacity for a given groove depth. Covers shaft and bore.
ST retaining rings, DIN 6799 and crescent rings — pressed into the groove from the side. No need to slide ring over shaft end. Shaft only. Limited load capacity versus axial types.
L-rings (linear spring) and W-rings (progressive spring) for bearing stack end-play compensation and axial preloading. Calculates whether the ring can compensate the tolerance stack and the resulting preload force range.
Start here if you are designing a retaining ring from scratch. Standard DIN 471/472 tapered rings give the best balance of load capacity, groove depth, and assembly stress for shaft and bore applications.
Key differences between the main ring types to guide your selection:
Ring type
Groove needed
Section
Shaft / Bore
Assembly
Best for
Grooved Axial (A)
✓ Required
Tapered
Both
Axial — pliers
Highest load capacity, rolling bearings, gearboxes
Snap Ring / Circlip (E)
✓ Required
Uniform
Both
Axial — pliers or mandrel
Low cost, automotive, consumer products
Grip Ring (B)
✗ None needed
Tapered
Shaft only
Axial — pliers
Adjustable location, no groove possible, 1.5–30 mm
Radial Ring (D)
✓ Required
Varies
Shaft only
Radial — push in
Long shafts, shoulders present, quick assembly
L-ring / W-ring (C)
✓ Required
Conical/convex
Both
Axial — pliers
End-play compensation, bearing preload
What is a Retaining Ring?
A retaining ring is an open-ended spring element that seats in a machined groove on a
shaft or inside a bore. It provides an axial shoulder that prevents a machine component
— a bearing, gear, pulley or similar — from sliding off the shaft or being pushed
through the bore.
The ring transmits axial load by dishing: when a component presses against the ring,
the ring tilts conically until it bears against the groove wall. The load is then
carried by the groove material. The ring itself must resist this dishing force without
permanently deforming — which is why ring thickness, width, and material stiffness
all matter to the load capacity.
The tapered retaining ring — patented in Germany in 1927 and now
standardised as DIN 471 (shaft) and DIN 472 (bore) — is the dominant type because
its eccentric contour causes it to deform in a near-circular manner when expanded or
contracted for assembly. This uniform deformation allows the ring to bridge much
larger diameter differences than a constant-section snap ring of the same thickness,
enabling deeper grooves and higher load capacity.
About these calculators: all modules design rings from generalised
mechanical design relationships. Results are first-pass design values for engineering
assessment. Always verify against the selected manufacturer's published dimensional
data, actual material properties, and applicable tolerance conditions before committing
to production tooling or safety-critical applications. Free to use — no warranty.
Frequently Asked Questions
What is the difference between a retaining ring and a snap ring?
A retaining ring (DIN 471/472 type) has a tapered radial width — wider at the body, narrowing to the lugs. This taper causes it to deform nearly circularly when assembled, which reduces peak bending stress and allows larger diameter changes. A snap ring has constant width and deforms as a shallow arch when opened with pliers, concentrating stress at the point opposite the gap. Tapered rings carry higher loads for the same cross-section and need less assembly clearance. Both types require a machined groove.
Does groove width affect the load capacity of the assembly?
No. Groove width has no effect on axial load capacity. The ring sits with axial play in the groove regardless of width, and the dishing mechanism that transmits load into the groove wall is independent of groove width. Wider grooves are therefore preferable — they are easier to machine to the required precision and have no strength disadvantage. The minimum groove width must simply exceed the maximum ring thickness to allow the ring to seat.
Why does chamfer size matter for retaining ring load capacity?
The chamfer on the abutting component (such as a rolling bearing) creates a lever arm between the ring face and the groove wall edge. The larger this lever arm h, the more the ring dishes under load, and the lower the load capacity. A 1.5 mm chamfer on a 25 mm shaft gives h = 1.55 mm — more than double the sharp-cornered value of 0.35 mm — and can reduce ring load capacity by more than 50%. Always input the actual chamfer dimension when designing for rolling bearing retention.
Which DIN standard covers retaining ring grooves?
DIN 471 specifies both the ring dimensions and the groove dimensions for shaft retaining rings. DIN 472 does the same for bore rings. The groove diameter d₂, groove width m, and collar length n are all specified relative to the nominal shaft/bore diameter d₁. These calculators allow you to specify groove depth independently for custom or non-standard applications, while the DIN standard values provide sensible defaults.
When should I use a support washer (Module F) alongside a retaining ring?
A support washer (DIN 988) reduces the effective lever arm h by filling the space between the ring and the abutting component. This directly increases the ring load capacity — the washer bears against the component, and the ring bears against the washer with a much smaller lever arm than if it bore against the component chamfer directly. Support washers are particularly useful with rolling bearings that have large corner radii, or when the existing ring selection cannot meet the load requirement without the washer.
Free retaining ring and circlip design calculators from AbarTech Ltd, Dyserth, North Wales. Covering grooved axial rings (DIN 471/472), snap rings, grip rings, radial rings, support washers and assembly verification — built from first-hand experience designing and manufacturing retaining ring production machinery and complete wire-to-packed-part production lines.
AbarTech