STANDARD REFERENCE / YZEFY SPROCKETS
ANSI sprockets
ANSI sprockets are toothed wheels for roller chain drives identified by American standard references such as #40, #50, #60 and #80. They are used in industrial transmission, conveyors, packaging equipment, agricultural machinery and OEM drives. Selection starts with the complete ANSI chain reference, then adds strand count, number of teeth, bore, keyway and hub dimensions. For a custom or replacement sprocket, send the chain marking, drawing, sample or measured dimensions. The RFQ should also include quantity and application details so the sprocket can be checked against the mating chain and shaft.
Standard reference
ANSI Sprockets
- SpecificationDetails
- Standard referenceASME B29.1 for precision power transmission roller chains, attachments and sprockets
- Common chain references#25, #35, #40, #50, #60, #80, #100 and #120
Quick Specifications
| Specification | Details |
|---|---|
| Standard reference | ASME B29.1 for precision power transmission roller chains, attachments and sprockets |
| Common chain references | #25, #35, #40, #50, #60, #80, #100 and #120 |
| Reference pitch range | 6.350 mm to 38.100 mm in the table below |
| Strand | Simplex, duplex and triplex, with the complete strand suffix stated in the RFQ |
| Sprocket forms | Type A plate, Type B hub, Type C double hub, idler and drawing-defined forms |
| Bore options | Pilot bore, finished bore, keyed bore and custom shaft interface |
| Selection basis | Chain reference, pitch, roller or bush diameter, inner width, teeth, strand and mounting dimensions |
| Custom orders | Drawing, sample, specification or measured existing sprocket |
Available Sizes
The ANSI size pages below hold the current child-page entry points for the listed chain references.
Chain & Size Reference
The table gives common ANSI chain dimensions used for a first sprocket fit review. Dimensions are in millimetres. The ANSI #25 and #35 references use the bush diameter in the technical tables commonly used for this chain family, rather than a separate rotating roller. Confirm the exact chain manufacturer’s dimensions before releasing a drawing.
| ANSI chain | Pitch | Roller or bush diameter | Inner width |
|---|---|---|---|
| #25 | 6.350 | 3.300 | 3.180 |
| #35 | 9.525 | 5.080 | 4.780 |
| #40 | 12.700 | 7.920 | 7.950 |
| #50 | 15.875 | 10.160 | 9.530 |
| #60 | 19.050 | 11.910 | 12.700 |
| #80 | 25.400 | 15.880 | 15.880 |
| #100 | 31.750 | 19.050 | 18.900 |
| #120 | 38.100 | 22.230 | 25.220 |
These are chain dimensions, not the finished sprocket dimensions. Pitch diameter and outside diameter depend on the number of teeth. Tooth width also depends on simplex, duplex or triplex construction and the selected sprocket tooth form.
Available Sprocket Configurations
Sprocket forms
- Type A plate sprockets for compact drives or assemblies with a separate hub.
- Type B sprockets with a hub on one side for shaft mounting.
- Type C sprockets with a hub on both sides or a wider shaft interface.
- Idler, split, weld-on, bushing-mounted and other drawing-defined forms where the equipment requires them.
Strand configurations
Simplex sprockets carry one chain row. Duplex and triplex sprockets use the matching transverse spacing for two or three chain rows. A sprocket marked only by #40 or #50 is incomplete until the strand arrangement and tooth count are known.
Materials
Carbon steel is common for general industrial drives. Alloy steel is considered when load, shock or tooth wear requires a different material specification. Stainless steel is used when corrosion resistance or washdown conditions are important. Cast iron, aluminum and engineering plastics may be considered for specific low-load, weight-sensitive or corrosion-controlled applications.
Specify the material grade, supply condition and any certificate requirement in the RFQ. Material choice should follow load, speed, shock, lubrication, corrosion, temperature and cleaning conditions. The material name alone is not a complete purchase specification.
Heat Treatment & Surface Treatment
Tooth hardening and induction hardening are used to address tooth wear and repeated load. Carburizing may be selected when a hard case and a tougher core are required by the drawing. Protective surface treatments can be considered for corrosion exposure, storage or washdown environments.
State the required hardness, case depth, treatment area, surface finish and inspection method when these values are controlled by the application. If no treatment is specified, provide the load cycle, speed, lubrication and environment so the treatment can be reviewed with the material and tooth geometry.
Custom ANSI Sprockets
Custom ANSI sprockets are defined by more than the chain number. Send the ANSI chain size, number of teeth, strand, bore, keyway, hub dimensions and quantity. A drawing or sample should also identify material, heat treatment, surface treatment, tolerances, marking and inspection requirements.
For a drawing-based order, include the drawing revision and the intended mating chain. For a sample-based order, add photographs, tooth count, pitch, roller or bush diameter, inner width, face width and shaft measurements. Application speed, load, center distance and operating environment help resolve details that a worn sample cannot show.
Replacement Sprockets
Replacement ANSI sprockets are reviewed against the chain and shaft together. Provide the old chain marking, tooth count, bore, keyway, hub, face width and any part number. A photo of the chain engaged with the old sprocket helps identify a wrong chain family, but it does not replace dimensional checks.
Do not copy worn tooth tips as the design profile. If the failure involved elongation, poor alignment, inadequate lubrication or contamination, inspect the chain and the mating sprocket before ordering only one replacement part.
Applications
ANSI sprocket inquiries commonly come from equipment using inch-based chain designations or an ANSI drawing. Typical applications include North American power transmission, packaging and indexing machinery, agricultural equipment, conveyors, material handling stations and OEM machines with a controlled chain specification. MRO replacements often begin with a chain marking and an old sprocket rather than a complete drawing.
Application type narrows the review, but it does not select the sprocket by itself. Load, speed, tooth count, chain line, environment and shaft interface still control the final part.
Standard & Compatibility Notes
ASME B29.1 is the primary standard reference for ANSI precision power transmission roller chains, attachments and sprockets. ANSI chain references also appear in ISO 606 as the A series. A similar pitch does not prove interchangeability. For example, an ANSI A-series reference and an ISO B-series reference can share a pitch while having different roller dimensions, inner width or transverse spacing.
Use the complete chain designation and the applicable drawing. Do not replace an ANSI sprocket with an ISO, DIN, BS or JIS sprocket only because the number looks similar. The chain’s roller or bush diameter, inner width, strand spacing and sprocket tooth form must be checked together.
How to Select
- Identify the standard and complete ANSI chain number.
- Confirm simplex, duplex, triplex or another defined strand arrangement.
- Record driver and driven tooth counts, speed ratio and center distance.
- Confirm pitch, roller or bush diameter, inner width and chain line.
- Select Type A, Type B, Type C or another required sprocket form.
- Specify bore, keyway, locking method, hub dimensions and axial clearance.
- Add material, treatment, finish, quantity and inspection requirements.
- Send a drawing, sample or measured photograph when any dimension is uncertain.
FAQ
What are ANSI sprockets?
ANSI sprockets are made for chain drives identified by American standard references such as #40, #50 and #60. The complete chain reference, strand, teeth and shaft interface are needed to select the part.
What do #40, #50 and #60 mean?
They identify common ANSI chain sizes. Their pitches are 12.700 mm, 15.875 mm and 19.050 mm respectively, but pitch alone does not define roller geometry, chain width or sprocket mounting.
Can an ANSI #40 chain use any #40 sprocket?
No. Check roller diameter, inner width, tooth count, strand spacing, tooth form, bore and keyway. A nominal #40 marking is not a complete purchase specification.
Are ANSI and ISO sprockets interchangeable?
Not automatically. ISO 606 includes A and B series with different chain families. Compare the actual chain dimensions and the equipment drawing before selecting a substitute.
Can an ANSI sprocket be made from a drawing or sample?
Yes, a drawing, sample or measured existing sprocket can start the technical review. Include the mating chain and shaft dimensions so the replacement is not defined from worn teeth alone.
What information is needed for an ANSI sprocket quote?
Send chain reference, number of teeth, strand, bore, keyway, hub, quantity and application. Add a drawing, sample photo or measured dimensions for custom and replacement work.
Request a Quote for ANSI Sprockets
Send the ANSI chain reference, number of teeth, strand count, bore, keyway, hub, quantity and application. For a custom or replacement part, attach the drawing, sample photo, old sprocket dimensions or existing part number. The quote can then be reviewed against the intended chain and shaft interface.