API 671 Special-purpose couplings
CurrentLatest edition found. Still confirm amendments with the publisher.
- Edition
- API 671 5th ed., 2020 (R2026)
- Publisher
- API
- Part family
- Couplings & alignment
- Reviewed
- 23 October 2026 · source checked
Is API 671 still current?
Yes. API 671 5th ed., 2020 (R2026) is the latest edition MechAtlas found (MechAtlas review: 23 October 2026). Check the publisher for amendments before you specify it.
What it covers
Special-purpose couplings
Equivalent and related standards
| Standard | Relationship | Note |
|---|---|---|
| ISO 10441 | Similar purpose — not interchangeable without an engineering check |
“Similar” never means interchangeable without an engineering check.
Parts that use API 671
- Flexible shaft coupling (USA (ASME / ASTM), main)
Connects two shafts (motor to pump or gearbox) and takes small misalignment while passing torque.
Special-purpose couplings for refinery service.
Official source
MechAtlas does not reproduce standards. Check the official edition at the publisher's page for API 671 or the API store.
Open in MechAtlasCheck a drawing callout
Other couplings & alignment standards
- ANSI/AGMA 9002-C14 Current
Coupling bores and keyways (inch) - ANSI/ASA S2.75 Part 1 Current
Shaft alignment methods and tolerances, horizontal machines - DIN 740-1/-2 Current
Flexible couplings: terms and parameters - IS 12405 Current
Gear-type flexible couplings (indigenous) - IS 2693 / IS 14285 Current
Bush-type / tyre-type couplings - ISO 10441 Current
Special-purpose flexible couplings - ISO 14691 Current
Flexible couplings, general-purpose (oil and gas) - JIS B 1452 Current
Flange-type flexible shaft couplings - JIS B 1453 Current
Gear-type shaft couplings