Last updated: 10 November 2026.
Direct answer. China's registry lists 22 sprocket standards: 12 current, 10 abolished, all recommended rather than mandatory. GB/T 1243-2024 governs short-pitch roller-chain sprockets, and GB/T 4140-2026 replaced GB/T 4140-2003 on 1 November 2026. A drawing citing the 2003 or 2006 edition cites a withdrawn file.
China's standards registry holds 22 sprocket records, 12 current and 10 abolished. What changed on 1 November 2026, and which numbers buyers still misquote.
Chinese sprocket standards are not one document. They are a family of recommended standards organised by the type of chain the sprocket drives, and the registry that tracks them shows a family in the middle of a quiet generational turnover: four of its current records were issued in 2024 or later, while ten of its twenty-two records are withdrawn editions that still appear on drawings.
This page reads the national standards registry as retrieved on 10 November 2026 and reports the record set, the changeovers, and the two records that are not drive sprockets at all.
A query on the registry's own Chinese term for sprocket (shown in the term table below) returns 22 records, retrieved in full with no shortfall. Of those, 12 are current, 10 are abolished, and all 22 are recommended standards — the registry records none of them as mandatory.
That last point is the one foreign buyers get wrong most often. "GB" without a "/T" is a mandatory standard and "GB/T" is a recommended one; every sprocket record here carries the "/T" suffix. A sprocket standard is therefore a specification a contract chooses to adopt, not a legal minimum the state imposes.
| Standard | Title as registered | Issued | Effective |
|---|---|---|---|
| GB/T 10855-2016 | Tooth chain and sprockets | 2016-02-24 | 2016-09-01 |
| GB/T 10857-2005 | S-type and C-type steel roller chains, attachments and sprockets | 2005-09-19 | 2006-04-01 |
| GB/T 1243-2024 | Short-pitch precision roller chains, bush chains, attachments and sprockets for transmission | 2024-05-28 | 2024-12-01 |
| GB/T 15390-2005 | Welded bent-plate chains for engineering, attachments and sprockets | 2005-09-19 | 2006-04-01 |
| GB/T 19927-2005 | Welded bent-plate chains for dragging, attachments and sprockets | 2005-09-19 | 2006-04-01 |
| GB/T 24503-2024 | Drive sprockets for mining round-link chains | 2024-09-29 | 2025-04-01 |
| GB/T 4140-2026 | Flat-top chains and sprockets for conveyors | 2026-04-30 | 2026-11-01 |
| GB/T 47047-2026 | Offshore structures — mobile offshore units — anchor chain wheels | 2026-01-28 | 2026-08-01 |
| GB/T 5269-2008 | Double-pitch precision roller chains, attachments and sprockets for drive and conveyor | 2008-07-01 | 2009-02-01 |
| GB/T 5858-1997 | Bent-plate roller chains and sprockets for heavy-duty transmission | 1997-07-04 | 1997-12-01 |
| GB/T 8350-2008 | Conveyor chains, attachments and sprockets | 2008-07-01 | 2009-02-01 |
| GB/T 9785-2007 | Chains and sprockets — vocabulary | 2007-04-18 | 2007-11-01 |
Read the effective-date column rather than the issue year. Two records are newer than their titles suggest: GB/T 1243-2024 has been in force since December 2024, and GB/T 24503-2024 since April 2025. Anyone quoting the 2006 or 2009 editions of those numbers is quoting a superseded file.
GB/T 4140-2026 for flat-top conveyor chains and sprockets took effect on 1 November 2026, replacing GB/T 4140-2003. Both records sit in the registry — the 2026 edition as current, the 2003 edition as abolished — which is how the registry expresses a supersession it does not spell out in words.
The practical consequence is narrow but real. Flat-top chain is a conveyor product, not a drive product, so most sprocket enquiries never touch this number. If yours does, a drawing or a supplier datasheet dated before November 2026 names the withdrawn edition by default, and the fix is to ask which edition the inspection will be run against rather than to assume either.
The registry matches on the word, not on the function, and two current records have nothing to do with a sprocket driving a chain.
GB/T 47047-2026 is an offshore-structure standard for the anchor chain wheel of mobile offshore units. The Chinese term contains the same characters as sprocket, but the object is the wheel that runs an anchor chain on a rig or an accommodation unit. It is not a transmission sprocket and this page does not treat it as one.
GB/T 9785-2007 is a vocabulary standard. It fixes the words — chain, sprocket, tooth profile — and not the geometry. A supplier quoting it as the specification for a sprocket is quoting a dictionary.
We flag both because a keyword search across the registry returns them in the same result set as the eleven dimensional standards, and a buyer assembling a specification from search results alone will pick them up.
| Abolished standard | Title as registered | Replaced by |
|---|---|---|
| GB/T 1243-1997 | Short-pitch precision roller chains and sprockets for transmission | GB/T 1243-2006, then GB/T 1243-2024 |
| GB/T 1243-2006 | Short-pitch precision roller chains, bush chains, attachments and sprockets | GB/T 1243-2024 |
| GB/T 10855-2003 | Tooth chain and sprockets | GB/T 10855-2016 |
| GB/T 15390-1994 | Welded bent-plate chains and sprockets for engineering | GB/T 15390-2005 |
| GB/T 24503-2009 | Drive sprockets for mining round-link chains | GB/T 24503-2024 |
| GB/T 4140-2003 | Flat-top chains and sprockets for conveyors | GB/T 4140-2026 |
| GB/T 5269-1999 | Double-pitch precision roller chains and sprockets for drive and conveyor | GB/T 5269-2008 |
| GB/T 6076-2003 | Short-pitch precision bush chains and sprockets for transmission | No successor in this record set |
| GB/T 8350-2003 | Conveyor chains, attachments and sprockets | GB/T 8350-2008 |
| GB/T 9785-1988 | Chains and sprockets — terminology | GB/T 9785-2007 |
The "replaced by" column is our reading of the record set, not a field the registry fills in: the registry marks a record abolished and lists the new edition separately, without a pointer between them. Where no successor appears in the twenty-two records we retrieved, we say so instead of guessing.
GB/T 6076-2003 is the interesting one. Its subject — bush chains for transmission — is now covered inside the title of GB/T 1243-2024, which names bush chains alongside roller chains. Whether that is the formal successor is not stated in any record we retrieved, so we do not assert it.
Nothing here gives a tooth count, a pitch, a bore, a keyway, a hardness range, a tolerance band, a load rating or a price. The registry records standard numbers, titles, issue dates, effective dates and a state field. It does not carry the text of any standard, and this page has not read the text of any standard. Dimensional values live inside those documents, behind the national standards reading system, and a supplier's claim about them is only as good as the edition they are working from.
What the registry does let you do is check the edition. Before you countersign a drawing, match the number and the year on it against the current records above.
Our recommendation, marked as ours rather than the registry's: name the standard with its year, and name the chain type in the same line. "GB/T 1243" alone leaves the edition open, and the difference between 2006 and 2024 is a document the buyer never saw. "GB/T 1243-2024, short-pitch precision roller chain and matching sprocket" leaves nothing to interpret.
For the adjacent part families, see our guides on couplings — which follows the same registry method for shaft couplings — and on anchor chains, where the chain standard rather than the wheel is the subject. If the part you are buying is a gear rather than a sprocket, the gear standard guide covers that record set separately.
| 中文 | English used on this page |
|---|---|
| 链轮 | sprocket |
| 齿形链和链轮 | tooth chain and sprockets |
| 滚子链、套筒链、附件和链轮 | roller chains, bush chains, attachments and sprockets |
| 短节距精密滚子链 | short-pitch precision roller chain |
| 双节距精密滚子链 | double-pitch precision roller chain |
| 弯板链、附件和链轮 | bent-plate chains, attachments and sprockets |
| 输送链、附件和链轮 | conveyor chains, attachments and sprockets |
| 平顶链和链轮 | flat-top chains and sprockets |
| 矿用圆环链驱动链轮 | drive sprockets for mining round-link chains |
| 锚链轮 | anchor chain wheel |
| 链条链轮术语 | chains and sprockets vocabulary |
The national standards registry returns 22 records for sprocket: 12 current and 10 abolished. All 22 are recommended standards with the GB/T prefix; the registry records none of them as mandatory.
GB/T 1243-2024, short-pitch precision roller chains, bush chains, attachments and sprockets for transmission. It was issued on 28 May 2024 and took effect on 1 December 2024, replacing GB/T 1243-2006, which the registry now marks abolished.
Yes. GB/T 4140-2026, flat-top chains and sprockets for conveyors, took effect on 1 November 2026 and replaced GB/T 4140-2003. Flat-top chain is a conveyor product, so the change touches conveyor sprocket specifications rather than drive sprockets.
No. It covers the anchor chain wheel of mobile offshore units. The Chinese title shares characters with sprocket, but the object is an anchor chain wheel on an offshore structure, not a transmission sprocket.
None of the 22 records is mandatory. In the GB system a mandatory standard carries the GB prefix and a recommended one carries GB/T; every sprocket record in the registry is GB/T, so a sprocket specification becomes binding through the purchase contract, not through the standard alone.
All sources retrieved 10 November 2026. This page is an independent reading of the sources listed; the official pages themselves are the specification.
| Fact used on this page | Source |
|---|---|
| S1 — 22 records for sprocket: 12 current, 10 abolished, all recommended; titles, issue dates, effective dates and state for every record listed above | National Standards Information Public Service Platform, State Administration for Market Regulation — registry query, retrieved 10 November 2026 https://std.samr.gov.cn/gb/search/gbQueryPage |
| S2 — Absence of a successor record for GB/T 6076-2003 within the retrieved set | Same registry query as S1, retrieved 10 November 2026 https://std.samr.gov.cn/gb/search/gbQueryPage |