Understand the 3 Major Retaining Ring Standards at a Glance｜JIS, DIN, and ANSI — What’s the Difference and How to Choose?

翰君陳
Oct 15
3 min read

1. What Is a Retaining Ring?

A retaining ring (circlip) is a small fastening component used to prevent parts from sliding axially along a shaft.It’s commonly seen in motors, gears, and bearings — essential for keeping machines running smoothly.

However, depending on the region or industry, retaining rings follow different design and dimension standards.Globally, the three most recognized systems are JIS (Japan), DIN (Germany), and ANSI (United States).

Let’s explore the key differences between these standards and how to choose the right one for your equipment.

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2. Comparison of the Three Major International Standards

Standard	Full Name & Code	Common Range	Key Features	Typical Applications
JIS (Japanese Industrial Standard)	JIS B 2804, B 2805	Mainstream in Taiwan	High dimensional accuracy, stable quality, interchangeable molds	Taiwanese and Japanese equipment, electronic production lines
DIN (German Industrial Standard)	DIN 471 (for shafts), DIN 472 (for bores)	Common in Europe	Well-standardized, excellent compatibility	European machinery, machine tools
ANSI (American Standard)	5000 Series (shaft), 5100 Series (bore)	North America and export markets	Thicker construction, higher strength	Automotive, heavy machinery, imported equipment

💡 Note:Though visually similar, size differences between standards can be 0.1–0.3 mm, which may cause looseness or installation failure. Always confirm the exact standard before purchasing.

Supplement: The Relationship Between ANSI and the 5000 Series

Many people confuse ANSI retaining rings with the 5000 Series, but they refer to different levels of classification.

ANSI stands for American National Standards Institute, the U.S. standardization body.
The 5000 (shaft) and 5100 (bore) Series are product lines developed under ASME B18.27 / ANSI B27.7.
The American manufacturer American Ring popularized these models, so the term “5000 Series” became synonymous with U.S.-standard rings.

👉 In short: ANSI is the standard system, while 5000/5100 refers to the actual series within that system.

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3. Why Understanding Standards Matters

Different countries and industries have varying requirements for size, tolerance, and strength.In Taiwan, most machinery follows JIS, making it the easiest to source.But if you’re working with European or American equipment, you’ll need to match their respective standards.

For example:

DIN is preferred in European machinery for its strong standardization.
ANSI is common in U.S. heavy machinery, valued for strength and thickness.
JIS dominates in Japanese and Taiwanese automation or electronics equipment.

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4. How to Choose the Right Standard

Here are three quick questions to help you decide:

1️⃣ Where is the equipment from?

Japanese equipment → choose JIS→

European equipment → choose DIN

American or heavy-duty machinery → choose ANSI

2️⃣ Do you need parts interchangeability?

Follow your customer’s specified standard if the parts must align with international supply chains.

3️⃣ What performance is most important?

For precision, stability, and easy local sourcing → JIS

For thickness and strength → ANSI

For cross-compatibility with European parts → DIN

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5. How Sheng Fong Precision Can Help

Sheng Fong Precision supplies complete retaining ring solutions across all three major standards — JIS, DIN, and ANSI — helping you verify dimensions and choose the right type with confidence.

Service Item	Description
Full Standard Support	JIS / DIN / ANSI series all available, with complete specifications
Material Options	Carbon steel, stainless steel, manganese phosphate, anti-rust coatings
Fast Delivery	In-stock standard sizes; short lead time for custom dimensions
Professional Assistance	Unsure which standard to use? We’ll help you compare dimensions and select the right one