6B Series Cast Iron QD Pulleys | 6-Groove A/B V-Belt Sheaves
6B series pulleys are manufactured for A, AX, AA, 4L, B, BX, BB, and 5L v-belts, ranging from 3.75″ to 38.35″ in diameter. Depending on the pulley size, they are made to use with SD, SK, SF, or E QD bushings, which we also stock. Most of our six-groove 6B QD bushed pulleys are manufactured from a high-strength grade 35 cast iron, are phosphate-coated, and are painted for anti-corrosion. The main benefit of using a QD (quick detachable) pulley is that if the bushing (hub) breaks, you don’t have to replace the whole assembly, or if just the pulley gets worn out, the same principle applies. The other significant benefit is that there is a broader range of bore options with QD pulleys than with the “fixed-bore” style.
6B Series Cast Iron QD Pulleys (6-Groove A/B V-Belt Sheaves)
Our 6B series six-groove QD (Quick Detachable) bushed pulleys are precision-machined power transmission components designed for heavy-duty industrial drives. Compatible with A (4L) and B (5L) classical V-belts—as well as AX, BX, AA, and BB profiles—this series features outside diameters ranging from 3.75″ to 38.35″. Depending on the pulley size, they are engineered to fit standard SD, SK, SF, or E QD bushings for versatile shaft mounting and torque transmission.
Key Features & Engineering Advantages
- High-Strength Construction: Precision machined from Grade 35 high-tensile gray cast iron to reliably handle continuous operational stress.
- Corrosion Protection: Phosphate conversion coated and painted to deliver excellent corrosion resistance in demanding operating environments.
- Factory Dynamic Balance: Dynamically balanced at the factory to maintain smooth operation, reduce drive vibration, and extend bearing service life.
- Flexible QD Bushing Design: Quick Detachable bushings provide exceptional shaft clamping force across a wide range of bore sizes. Replacing worn components individually reduces maintenance costs and system downtime.
6B QD Pulleys Dimensional Specifications
| Size | Bushing Type | Pulley Type | Pitch Diameter (5L/B) | Pitch Diameter (4L/A) | Outside Diameter | (E) | (F) | (L) | (M) | Pulley Weight (LBS) |
|---|---|---|---|---|---|---|---|---|---|---|
| 6B34SD | SD | E | 3.4″ | 3.0″ | 3.75″ | 3-31/32″ | 4-3/4″ | 1-13/16″ | 1-1/32″ | 6.7 |
| 6B36SD | SD | E | 3.6″ | 3.2″ | 3.95″ | 3-31/32″ | 4-3/4″ | 1-13/16″ | 1-1/32″ | 7.4 |
| 6B38SD | SD | E | 3.8″ | 3.4″ | 4.15″ | 3-31/32″ | 4-3/4″ | 1-13/16″ | 1-1/32″ | 8.0 |
| 6B40SD | SD | E | 4.0″ | 3.6″ | 4.35″ | 3-19/32″ | 4-3/4″ | 1-13/16″ | 21/32″ | 8.4 |
| 6B42SD | SD | E | 4.2″ | 3.8″ | 4.55″ | 3-19/32″ | 4-3/4″ | 1-13/16″ | 21/32″ | 9.0 |
| 6B44SD | SD | E | 4.4″ | 4.0″ | 4.75″ | 3-19/32″ | 4-3/4″ | 1-13/16″ | 21/32″ | 9.7 |
| 6B46SD | SD | A | 4.6″ | 4.2″ | 4.95″ | 21/32″ | 4-3/4″ | 1-13/16″ | 2-9/32″ | 10.1 |
| 6B48SD | SD | A | 4.8″ | 4.4″ | 5.15″ | 21/32″ | 4-3/4″ | 1-13/16″ | 2-9/32″ | 10.6 |
| 6B50SD | SD | A | 5.0″ | 4.6″ | 5.35″ | 21/32″ | 4-3/4″ | 1-13/16″ | 2-9/32″ | 11.0 |
| 6B52SD | SD | A | 5.2″ | 4.8″ | 5.55″ | 21/32″ | 4-3/4″ | 1-13/16″ | 2-9/32″ | 12.0 |
| 6B54SK | SK | A | 5.4″ | 5.0″ | 5.75″ | 17/32″ | 4-3/4″ | 1-15/16″ | 2-9/32″ | 13.0 |
| 6B56SK | SK | A | 5.6″ | 5.2″ | 5.95″ | 17/32″ | 4-3/4″ | 1-15/16″ | 2-9/32″ | 14.0 |
| 6B58SK | SK | A | 5.8″ | 5.4″ | 6.15″ | 17/32″ | 4-3/4″ | 1-15/16″ | 2-9/32″ | 14.6 |
| 6B60SK | SK | A | 6.0″ | 5.6″ | 6.35″ | 17/32″ | 4-3/4″ | 1-15/16″ | 2-9/32″ | 15.0 |
| 6B62SK | SK | A | 6.2″ | 5.8″ | 6.55″ | 17/32″ | 4-3/4″ | 1-15/16″ | 2-9/32″ | 16.0 |
6B64SK |
SK | A | 6.4″ | 6.0″ | 6.75″ | 17/32″ | 4-3/4″ | 1-15/16″ | 2-9/32″ | 17.0 |
| 6B66SK | SK | A | 6.6″ | 6.2″ | 6.95″ | 17/32″ | 4-3/4″ | 1-15/16″ | 2-9/32″ | 18.0 |
| 6B68SK | SK | A | 6.8″ | 6.4″ | 7.15″ | 17/32″ | 4-3/4″ | 1-15/16″ | 2-9/32″ | 19.0 |
| 6B70SF | SF | A | 7.0″ | 6.6″ | 7.35″ | 27/32″ | 4-3/4″ | 2-1/16″ | 1-27/32″ | 20.0 |
| 6B74SF | SF | A | 7.4″ | 7.0″ | 7.75″ | 27/32″ | 4-3/4″ | 2-1/16″ | 1-27/32″ | 22.0 |
| 6B80SF | SF | A | 8.0″ | 7.6″ | 8.35″ | 27/32″ | 4-3/4″ | 2-1/16″ | 1-27/32″ | 24.0 |
| 6B86SF | SF | A | 8.6″ | 8.2″ | 8.95″ | 27/32″ | 4-3/4″ | 2-1/16″ | 1-27/32″ | 26.0 |
| 6B94SF | SF | A | 9.4″ | 9.0″ | 9.75″ | 27/32″ | 4-3/4″ | 2-1/16″ | 1-27/32″ | 27.0 |
| 6B110SF | SF | A | 11.0″ | 10.6″ | 11.35″ | 27/32″ | 4-3/4″ | 2-1/16″ | 1-27/32″ | 32.0 |
| 6B124SF | SF | A | 12.4″ | 12.0″ | 12.75″ | 27/32″ | 4-3/4″ | 2-1/16″ | 1-27/32″ | 29.0 |
| 6B136SF | SF | A | 13.6″ | 13.2″ | 13.95″ | 27/32″ | 4-3/4″ | 2-1/16″ | 1-27/32″ | 44.0 |
| 6B154SF | SF | A | 15.4″ | 15.0″ | 15.75″ | 27/32″ | 4-3/4″ | 2-1/16″ | 1-27/32″ | 50.0 |
| 6B160SF | SF | A | 16.0″ | 15.6″ | 16.35″ | 27/32″ | 4-3/4″ | 2-1/16″ | 1-27/32″ | 54.0 |
| 6B184SF | SF | A | 18.4″ | 18.0″ | 18.75″ | 27/32″ | 4-3/4″ | 2-1/16″ | 1-27/32″ | 62.0 |
| 6B200E | E | A | 20.0″ | 19.6″ | 20.35″ | 7/32″ | 4-3/4″ | 2-3/4″ | 1-25/32″ | 74.0 |
| 6B250E | E | A | 25.0″ | 24.6″ | 25.35″ | 7/32″ | 4-3/4″ | 2-3/4″ | 1-25/32″ | 96.0 |
| 6B300E | E | A | 30.0″ | 29.6″ | 30.35″ | 7/32″ | 4-3/4″ | 2-3/4″ | 1-25/32″ | 119.0 |
| 6B380E | E | A | 38.0″ | 37.6″ | 38.35″ | 7/32″ | 4-3/4″ | 2-3/4″ | 1-25/32″ | 134.0 |
Model Technical FAQs
Q: Which belt profiles can be used with 6B series pulleys?
A: 6B series pulleys accommodate 6-groove A, AX, AA, 4L, B, BX, BB, and 5L V-belts.
Q: What bushing styles do 6B series QD pulleys require?
A: Depending on the overall diameter and torque requirement, 6B series pulleys use standard SD, SK, SF, or E QD bushings.
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How to choose power transmissions parts and industrial products which meet our requirement
| Chains | Sprockets | Pulleys | Timing belt Pulley | V-belt Pulley |
| Sheaves | Coupings | Bush &Hub | Gear& Rack | V-Belt |
| Locking Assembly | Pulley | Gearbox | Reducer | Shaft Collar |
| Rod End Bearing | Clevis | PTO | Chain Guide | Belt Guide |
| Rubber Buffer | Chain Tensioner | PTO Drive Shafts | Universal Joints | Roller Chains |
| Conveyor Chains | V-Belts | Worm Gearbox | Helical Gear | Worm |
| Agricultural Chain | CNC Proces Parts | Casting | Stamping | |
| Powder Metallurgy | CNC Proces Parts | Casting | Stamping |
What Products Do you sell ?
We are a group of factories, give customer one stop solution of power transmission and industrial products. We are in the position to supply wide range of products, including chains, sprockets, v-belt and v-belt pulleys, timing belt and timing belt pulleys, gears, speed reducers, motors, racks, couplings, and many other parts, like locking assembly, taper bushing, Chain guide, shaft collar, torque limiter, cam clutch, universal joint, motor base and motor slide, rod end, clevis, rubber mount, etc. We make special parts according to drawings and/or samples.
How to choose a gearbox which meets our requirement?
You can refer to our catalogue to choose the gearbox or we can help to choose when you provide
the technical information of required output torque, output speed and motor parameter etc.
What information shall we give before placing a purchase order?
a) Type of the gearbox, ratio, input and output type, input flange, mounting position, and motor informationetc.
b) Housing color.
c) Purchase quantity.
d) Other special requirements.
What industries are your gearboxes being used?
Our gearboxes are widely used in the areas of textile, food processing, beverage, chemical industry,
escalator,automatic storage equipment, metallurgy, tabacco, environmental protection, logistics and etc.
What is the producing process?
Production process including raw material cutting, machine processing, grinding, accessories cleaning, assemble, cleaning, stoving, oil coating, cover pressing, testing, package.
How to control the products quality?
Combining advanced equipment and strict management, we provide high standard and quality bearings for our customers all over the world.
What is the transportation?
-If small quantity , we Suggest to send by express, such as DHL,UPS, TNT FEDEX. If large amount, by air or sea shipping.
Can we design packaging?
-Yes. Default is regular packing, and we can make customer's own packing.
Can you provide OEM service?
-Yes, we work on OEM orders. Which means size, quantity, design, packing solution, etc will depend on your requests; and your logo will be customized on our products.
Can you give me discount on Power Transmissions Parts and Industrial parts?
-Yes, of course. Pls. send me your Email, you'll get more
Q: Are You a trading company or a manufacturer?
A: We Are the factory and have our Own trading company
Q: How Can I get an offer?
A: please send US quotation information: drawings, materials, weight, quantity and requirements, we can accept PDF, ISGS, DWG, STEP file format. If you don't have the drawings, please send us the samples, we can also quote you according to your samples.
Q: What is your minimum order size?
A: it is usually 100 pieces, but a low quantity is acceptable under some special circumstances.
Q: Do you provide samples? Is it free or extra?
A: Yes, we can provide samples free of charge, but we don't pay the freight.
Q: What is the lead time for mass production?
A: honestly, it depends on the number of orders. Normally, if you don't need the tools, deposit them after 30 days or so.
Q: What if the parts don't Work?
A: we can guarantee the quality, but if it happens, please contact us immediately, take some photos, we will check the problem and solve it as soon as possible.
Q: What are your terms of payment?
A: payment is less than US $1000,100% in advance. Payment: $1000,50% wire transfer in advance, balance before shipment,Other Terms of payment are negotiable








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