Idler Sprocket



There is a drive sprocket and idler sprockets on a typical roller chain drive application. Idler sprockets are designed in conveyor applications to “carry” or guide a roller chain in a straight line, around a bend, or in a complete 360-degree directional change. If an idler sprocket fails while in use, the result can be catastrophic depending on the application. Because of this, it is always important to monitor the status of your idler sprockets and use a high-quality sprocket. We stock a wide range of premium Idler sprockets for almost all roller chain sizes. We also supply idler sprockets for engineer class chains such as 81X idler sprockets, 55 idler sprockets, and welded steel idler sprockets. Below are the standard configurations for idler sprockets but additional types are available upon request.

Idler Sprocket ConstructionIdler Sprocket-1

Teeth – The teeth on our idler sprockets come standardly hardened from 30-teeth and under to ensure extended durability.
Sprocket Body – Our materials used in our idler sprocket bodies are premium 1018 & 1045 carbon steel, 304 or 316 stainless steel, and UHMW or Nylon plastics.
Idling Component – This component is typically a ball bearing, needle bearing, bronze, or nonmetallic plastic.

Chain Size Chain  Pitch x Inner plates width Z(Teeth No.) de(Outer Dia.) DP(Pitch No.) A(Teeth Width) D1(Bearing Bore Dia.) H(Bearing Bore length) F(Bearing outer dia. J(Bearing width)
05B 8mmX3mm 23 62 58.75 2.8 16 18.3 40 12
06B 3/8 X 7/32 21 68 63.91 5.3 16 18.3 40 12
081 1/2 X 1/8 18 78.9 73.14 3 16 18.3 40 12
083 1/2 X 3/16 18 78.9 73.14 4.5 16 18.3 40 12
084 1/2 X 3/16 18 78.9 73.14 4.5 16 18.3 40 12
08B 1/2 X 5/16 16 69.5 65.1 7.2 16 18.3 40 12
08B 1/2 X 5/16 18 77.8 73.14 7.2 16 18.3 40 12
10B 5/8 X 3/8 14 78 71.34 9.1 16 18.3 40 12
10B 5/8 X 3/8 15 83 76.36 9.1 16 18.3 40 12
10B 5/8 X 3/8 17 93 86.3 9.1 16 18.3 40 12
12B 3/4 X 7/16 13 87.5 79.59 11.1 16 18.3 40 12
12B 3/4 X 7/16 15 99.8 91.63 11.1 16 18.3 40 12
16B 1 X 17.02mm 12 109 98.14 16.2 20 17.7 47 14
20B 1 1/4 X 3/4 13 147.8 132.65 18.5 25 21 52 15

Idler Sprocket Type

When using an idler sprocket, you want the least amount of friction with your setup; the utilization of high-quality components such as bearings, plastics, or bronze must be used to eliminate as much friction as possible. Thus making your design more effective and energy-efficient. An example of our dedication to maintaining high-quality idler sprockets on our ball bearing configuration (the most common type) is we utilize sophisticated designed deep-groove ball bearings that meet or exceed ABEC 3 tolerances, use grade 10-balls, and has motor bearing rated Polyrex EM grease to ensure you get an idler sprocket with the best possible performance. Regardless of which configuration you use, we make and provide the best performing idler sprocket on the market.

(1)Idler Sprockets With Ball Bearing

Idler Sprocket-3

Your conveyor system has a complex design that includes more than just gears and chains. Maintain a nearly perfect system with idler sprockets from USA Roller Chain. Our parts are different than the standard star-shaped sprockets found across industries. Test your system’s strength with this ball-bearing gear. Each sprocket comes with a sealed ball-bearing centerpiece that protects the permanent lubrication. Dust and grime don’t have a chance at entering these chain idler sprockets. Never overlook the importance of your idler sprockets because they create longevity in an otherwise volatile setup. Vibrations and wear are quickly controlled. The tension that you demand from these ball chain sprockets will deliver too. Could you choose from our prefabricated stock? We’re also pleased to customize your order. Let us know about a particular sprocket with bearing you need so we can create the parts for you. USA Roller Chain supports your industry with precision quality.

Our ball-bearing idler sprockets for roller chains use high-quality high-precision ball bearings with metal or rubber shields to keep contaminants from Sandberg grease. These sprockets are on the shelf in ANSI Sizes #25 – #140, but we can make any other sizes or tooth count shown below in a fast lead time with our in-house machining facility.

(2)Needle Bearing Idler Sprockets

Idler Sprocket-4

Our needle-bearing idler sprockets are manufactured using high-quality bearings and premium sprockets. Typically this style of idler sprocket is used in high-speed applications because of the decreased amount of friction and increased stability. Below are the standard sizes of needle-bearing idler sprockets, but additional sizes are available. Contact our customer support team to get a quote on a stock or non-stock size needle-bearing sprocket, and we will be happy to assist you!

(3)Bronze Bushed Idler Sprockets

Idler Sprocket-5

Bronze bushed idler sprockets are highly durable. Bronze is used because it is lubricating, economical, and easy to press into sprockets. Our bronze bushed sprockets are manufactured using high-quality bronze with high-strength heat-treated sprockets. Contact our customer support team to get a quote on a stock or non-stock size bronze bushed sprocket, and we will be happy to assist you!

(4) Non-Metallic Ball Bearing Idler Sprockets

Idler Sprocket-6

Nonmetallic ball bearing idler sprockets are manufactured using high-quality UHMW and a stainless steel ball-bearing. They are typically found in harsh environments as well as in food-grade applications. They are also suitable for applications that require less weight. Contact our customer support team to get a quote on a stock or non-stock size nonmetallic ball bearing idler sprocket, and we will be happy to assist you!