#120 (1-1/2") Pitch Sprockets
ANSI #120 sprockets are sized for 1-1/2 inch (38.1 mm) pitch roller chain: the industry-standard size for continuous high-load operation, shock-resistant applications. Our BlackStar #120 sprockets are precision-cut from medium carbon steel with a hardened tooth profile, available in tooth counts from 9 to 95 and three hub configurations (A-plate, B-hub, C-hub) for direct shaft mounting or bushing installation.
When To Use #120 Sprockets
#120 chain has a 1-1/2" pitch with 7/8" roller diameter. Working load capacity is approximately 7,500 lbs per strand, with average ultimate tensile strength of 34,000 lbs. This combination makes #120 ideal for:
- Industries: mining equipment, large industrial conveyors, heavy machinery, pump drives, food processing
- Common applications: underground mining, large palletizers, sugar mills, heavy lumber processing, oil field equipment
- Replacement of existing #120 sprockets without changing chain specification
- New designs where engineering analysis specifies this ANSI size
#120 Pitch Specifications
| ANSI Designation | #120 |
| Pitch (P) | 1-1/2" (38.1 mm) |
| Roller Diameter | 7/8" |
| Pin Diameter | 0.437" |
| Average Tensile Strength | 34,000 lbs |
| Working Load (Single Strand) | 7,500 lbs |
| ANSI Standard | B29.1 (Inch Series Precision Roller Chain) |
How To Select The Right Sprocket
Three specifications drive sprocket selection for any chain drive:
1. Tooth Count
More teeth means smoother chain engagement and reduced wear per tooth, but increases overall diameter. As a rule of thumb: drive sprockets should have at least 17 teeth for high-speed applications, and at least 19 teeth for shock-loaded systems. Driven sprockets can go larger for speed reduction. We stock 9-95 tooth options for most pitches.
2. Hub Style
Three hub styles match different mounting needs:
- A-Plate: Flat sprocket, no integral hub, use with a bushing (QD or Taper-Lock) for tool-free shaft removal.
- B-Hub: Hub on one side of the sprocket, direct shaft mounting with set screws or keyway.
- C-Hub: Hubs on both sides, for higher torque transmission and longer engagement.
3. Bore Type
Plain stock bore lets you machine to a custom shaft size. Finished bore with keyway and set screws mounts directly. QD or Taper-Lock requires a matching bushing but allows fast field removal.
Chain & Component Compatibility
#120 sprockets pair with #120 ANSI standard roller chain. For multi-strand applications, you need a matching multi-strand sprocket: a #120-2 (double-strand) sprocket for #120-2 chain. Our Lynx chain line offers cottered and riveted variants in single, double, and triple strand configurations.
Find the matching chain, connecting links, and offset links for your #120 sprocket drive:
→ #120 Pitch Chain→ All Lynx Chain→ Bushings
