Description
ANSI #25 Stainless Steel
Sprockets
Precision-machined 304 stainless sprockets for #25 roller chain — combining ANSI B29.1 dimensional compliance with full corrosion resistance for food, pharmaceutical, and industrial process-environment drives.
ANSI #25 Stainless Steel Sprockets — Overview & Applications
ANSI #25 stainless steel sprockets are engineered for the #25 roller chain standard — one of the most widely specified roller chain sizes in North American, Japanese, and international industrial machinery. The 1/4″ (6.35 mm) pitch places this sprocket in the light duty category, where the combination of precise ANSI B29.1 dimensional compliance and 304 stainless steel construction makes it the default specification for any drive system in a corrosive, hygiene-regulated, or wet operating environment. Hangzhou Ever-Power manufactures ANSI #25 stainless sprockets from solid 304 stainless bar, with CNC-hobbed tooth profiles and H7 bore tolerance across the full tooth count range.
The choice of 304 stainless steel over carbon steel for ANSI #25 sprockets is driven by the operating environment rather than load capacity — 304 stainless provides adequate mechanical properties for the load range of #25 chain in most industrial applications, and its passive chromium oxide surface eliminates the corrosion failure mode that limits carbon steel service life in food processing washdown zones, pharmaceutical cleanrooms, chemical plant atmospheres, and outdoor installations. The non-magnetic character of austenitic 304 stainless also prevents interference with metal detection systems in food manufacturing lines, a secondary specification requirement that carbon steel components cannot meet without additional non-ferrous shielding.
Our ANSI #25 stainless sprockets cover 9T – 20T tooth counts, with OD, bore, hub, and weight progressing systematically across the range. All bore finishing is to H7 tolerance as standard; DIN 6885 keyway and set-screw configurations are available on order. Custom tooth counts, non-standard bores, and OEM part marking are produced without minimum quantity restrictions as part of our standard manufacturing service. As an established ANSI roller chain sprocket manufacturer with over two decades of export history, we deliver to customers in North America, Europe, Southeast Asia, and Australia with full export documentation.
Chain Parameters & Dimensional Specifications
ANSI #25 Stainless Sprocket Dimensional Table
Outside diameter, stock bore, minimum bore, maximum bore, hub length, and weight for each tooth count. All dimensions in inches; weight in pounds.
| Teeth | OD (in) | Stock Bore | Min. Bore | Max. Bore | Hub L | Weight |
|---|---|---|---|---|---|---|
| 9 | 0.837″ | 1/4″ | 1/4″ | 7/16″ | 1/2″ | 0.03 lbs |
| 10 | 0.919″ | 1/4″ | 1/4″ | 1/2″ | 1/2″ | 0.03 lbs |
| 11 | 1.001″ | 1/4″ | 5/16″ | 9/16″ | 1/2″ | 0.03 lbs |
| 12 | 1.083″ | 1/4″ | 3/8″ | 5/8″ | 1/2″ | 0.06 lbs |
| 13 | 1.164″ | 1/4″ | 7/16″ | 23/32″ | 1/2″ | 0.07 lbs |
| 14 | 1.246″ | 1/4″ | 1/2″ | 13/16″ | 1/2″ | 0.08 lbs |
| 15 | 1.327″ | 1/4″ | 9/16″ | 7/8″ | 1/2″ | 0.09 lbs |
| 17 | 1.490″ | 3/8″ | 5/8″ | 1″ | 1/2″ | 0.14 lbs |
| 18 | 1.571″ | 3/8″ | 3/4″ | 1-1/8″ | 1/2″ | 0.16 lbs |
| 20 | 1.734″ | 3/8″ | 7/8″ | 1-1/4″ | 1/2″ | 0.2 lbs |
304 Stainless Steel — Material Excellence for ANSI Sprockets
ANSI #25 sprockets in 304 stainless steel serve environments where corrosion resistance is the decisive material requirement. The 18% chromium / 8% nickel composition of 304 stainless generates a self-passivating oxide layer that resists attack from the cleaning agents, process fluids, and atmospheric moisture present in food processing, pharmaceutical, and chemical plant drive systems. Unlike carbon steel, which requires protective coatings that chip, crack, and eventually fail when exposed to CIP cleaning cycles, 304 stainless maintains its surface integrity through repeated washdown exposure without any maintenance intervention on the sprocket material itself.
The non-magnetic character of austenitic 304 stainless is particularly valuable in food production facilities equipped with inline metal detection systems. A ferromagnetic sprocket mounted near a metal detector can generate false positive signals that halt production lines, trigger quarantine procedures, and require manual product inspection. 304 stainless avoids this entirely, making it the standard material specification for all drive components in food production metal detection zones. For pharmaceutical cleanroom and GMP-regulated environments, 304 stainless meets material compliance requirements under FDA, EU 10/2011, and 3-A Sanitary Standards for food-contact equipment.
Precision Manufacturing Process
Industry Applications
Laboratory & Analytical Instruments
Automated sample handlers, fraction collectors, and diagnostic analyzer platforms use #25 chain drives for precise positioning. Non-magnetic 304 stainless avoids field interference in instruments where magnetic sensitivity is critical.
Pharmaceutical Packaging Lines
Tablet blister machines and capsule filling equipment index foil film using small-pitch chain drives that must tolerate IPA and peroxide sanitisation. #25 stainless sprockets meet GMP material requirements throughout the drive system.
Light Food Processing Equipment
Cup-filling machines, small-scale conveyor sections, and condiment portioning equipment use #25 chain in food-contact zones. Stainless construction meets FDA food-contact standards and CIP washdown cycles.
Light Industrial Automation
Pick-and-place machines, label applicators, and compact indexing tables in electronics and consumer goods assembly use small-pitch chain drives in humidity-present factory environments.
Horticulture & Laboratory Automation
Automated transplanting machines, small-scale greenhouse transport systems, and laboratory automation platforms use compact chain drives where light loading and corrosion resistance are simultaneously required.
Personal Care Production Equipment
Cosmetic filling lines and small-batch personal care product packaging systems require stainless chain components in zones with alcohol-based sanitisation. #25 stainless sprockets handle these light-duty drives reliably.
Custom Configurations & OEM Options
Standard ANSI #25 stainless sprocket orders require tooth count, bore diameter, and quantity. Custom keyway profiles, extended hubs, non-standard tooth counts, taper-lock bore configurations, and OEM part marking are available with no minimum order quantity. For non-standard tooth counts, provide a dimensioned drawing or specify the exact pitch circle diameter and outside diameter required alongside the tooth count; our engineering team will confirm feasibility and lead time before production begins.
📏 Standard Bore (H7)
Bore from stock size up to catalogue maximum. H7 tolerance. DIN 6885 keyway on request at no tooling surcharge.
🔧 Custom Keyway
Non-DIN key widths, depths, or Woodruff profiles from customer drawing. No additional lead time for common profiles.
📐 Extended Hub
Hub length beyond catalogue standard for cantilevered shaft clearance. Minor extensions without drawing sign-off.
🏷️ OEM / Private Label
Customer part numbers and brand marking by laser. Neutral or custom-branded packaging for OEM and private-label programs.
Why Choose Hangzhou Ever-Power for ANSI #25 Stainless Sprockets
Direct Factory Manufacturing: All machining from bar stock to finished part in-house. No subcontract operations. Full process control and dimensional traceability from material intake to final inspection.
EN 10204 3.1 Certificates: Material test certificates confirming 304 stainless chemical composition and heat number available on request for food, pharma, and regulated procurement categories.
Fast Standard Lead Times: Common ANSI #25 tooth counts in semi-finished stock. Standard bore configurations complete in 3–7 business days. Custom bore modifications add 2–4 days.
Global Export Experience: Export documentation in English — commercial invoice, packing list, certificate of origin, HS code classification — all handled in-house for smooth customs clearance.
