Zero Backlash Couplings - DieQua Corporation
Have Any Questions? Call Us: 630-980-1133

Series BK - Zero Backlash Flexible Bellows Couplings

The Series BK Bellows Couplings provide zero backlash and high torsional rigidity, perfect for servo and other precision applications.

Features & Benefits:
  • 11 Models: Provides a variety of connection options. All models rated for speeds up to 10,000 rpm.
  • Zero Backlash: Provides exact position and rotary motion.
  • High Torsional Rigidity: Maintains exact position when starting and stopping.
  • Low Inertia: Allows faster acceleration and deceleration with lower torque.
  • Compensates Misalignment: Allows axial, lateral, and angular misalignment for easier mounting.
  • Maintenance Free: No moving parts means an unlimited life with proper mounting.
  • Materials: Bellows are made of flexible, high-grade stainless steel. The hubs are made from aluminum or steel, depending on size. Hubs in stainless steel are also available.
  • Non-Standard Applications: Custom designs, with varied tolerances, keyways, non standard material and bellows, are available upon request. Also available with ATEX certification for explosion proof application requirements.
  • Temperature Range: -30° C to +120° C (-22° F to +270° F). High temperature options available.
Product Line Overview: Models BKC - BKH - BKL - BK1 - BK2 - BK3 - BK4 - BK5 - BK6 - BK7 - BK8

Model BKC - Economy Class Compact Coupling with Clamping Hub
(6 sizes with rated torque from 15-500 Nm)

Design Description: With a single ISO 4762 radial clamping screw per hub. Self opening clamp system optional: Loosening the clamping screw applies force to the pin, which will force the clamp into the open position for easy mounting and dismounting.

Bore Diameters: Inch or metric bores from 8 - 75 mm, or 0.3125 - 2.875 inches. Keyways are optional, but not necessary.

Sizes: BKC-15, BKC-30, BKC-60, BKC-150, BKC-300, BKC-500

Application Example:

Model BKH - Bellows Coupling with Split Hub
(10 sizes with rated torque from 15-15,000 Nm)

Design Description: Both clamping hubs are completely separable, due to split hubs and two radial screws ISO 4762 on each hub. The standard BKH Model is balanced to 16,000 RPM. Any imbalance of the clamping hubs is compensated for by bores located on the hub.

Bore Diameters: Inch or metric bores from 8 - 80 mm, or 0.3125 - 3.125 inches. Keyways are optional, but not necessary.

Sizes: BKH-15, BKH-30, BKH-60, BKH-80, BKH-150, BKH-200, BKH-300, BKH-500, BKH-800, BKH-1500

Application Example:

Model BKL - Economy Class Coupling with Clamping Hub
(10 sizes with rated torque from 2-500 Nm)

Design Description: With a single ISO 4762 radial clamping screw per hub. Self opening clamp system optional: Loosening the clamping screw applies force to the pin, which will force the clamp into the open position for easy mounting and dismounting.

Bore Diameters: Inch or metric bores from 4 - 62 mm, or 0.1875 - 2.375 inches. Keyways are optional, but not necessary.

Sizes: BKL-2, BKL-4.5, BKL-10, BKL-15, BKL-30, BKL-60, BKL-80, BKL-150, BKL-300, BKL-500

Application Example:

Model BK1 - Bellows Coupling with Flange Mount
(12 sizes with rated torque from 15-10,000 Nm)

Design Description: Flange hubs with a metric bolt circle. The ID and OD are concentrically machined to ISO H7 tolerances.

Bore Diameters: Fixed metric dimensions from 25 - 190 mm, depending on size.

Sizes: BK1-15, BK1-30, BK1-60, BK1-150, BK1-200, BK1-300, BK1-500, BK1-800, BK1-1500, BK1-4000, BK1-6000, BK1-10000

Application Example:

Model BK2 - Bellows Coupling with Clamping Hub
(10 sizes with rated torque from 15-1500 Nm)

Design Description: Single radial clamping screw per hub ISO 4762. Any imbalance of the clamping hubs is compensated for balancing by bores located on the inside of the hub.

Bore Diameters: Inch or metric bores from 8 - 80 mm, or 0.3125 - 3.125 inches. Keyways are optional, but not necessary.

Sizes: BK2-15, BK2-30, BK2-60, BK2-80, BK2-150, BK2-200, BK2-300, BK2-500, BK2-800, BK2-1500

Application Example:

Model BK3 - Bellows Coupling with Tapered Conical Sleeve
(12 sizes with rated torque from 15-10,000 Nm)

Design Description: With tapered conical sleeves and strong, captive ISO 4017 draw-off screws. Jack screws allow for easy dismounting. Compact and cost effective. High clamping forces. Shorter overall length. For space restricted installations.

Bore Diameters: Inch or metric bores from 10 - 180 mm, or 0.50 - 7.0 inches. Keyways are not available on this model.

Sizes: BK3-15, BK3-30, BK3-60, BK3-150, BK3-200, BK3-300, BK3-500, BK3-800, BK3-1500, BK3-4000, BK3-6000, BK3-10000

Application Example:

Model BK4 - Bellows Coupling for Fanuc Drives
(4 sizes with rated torque from 15-150 Nm)

Design Description: Spindle-side - with conical sleeves and strong captive ISO 4017 draw-off screws. Easy to assemble. High clamping forces due to conical sleeves.

Bore Diameters: One side has a fixed cone dimension with keyway, depending on size. Second side with inch or metric bores from 10 - 37 mm, or 0.50 - 1.375 inches.

Sizes: BK4-15, BK4-30, BK4-60, BK4-150

Application Example:

Model BK5 - Bellows Coupling with Tapered Press-Fit Connection
(9 sizes with rated torque from 15-1500 Nm)

Design Description: One side with a single radial clamping screw ISO 4762. One side includes backlash-free clamping hub and tapered press-fit device. Any imbalance of the clamping hub, is compensated for balancing bores located on the inside of the hub. Easy mounting and dismounting. Wear-free press-fit connection. Electrically and thermally insulated.

Bore Diameters: Inch or metric bores from 8 - 80 mm, or 0.3125 - 3.125 inches. Limited keyway availibility.

Options: Single position or multi-position configurations.

Sizes: BK5-15, BK5-30, BK5-60, BK5-80, BK5-150, BK5-300, BK5-500, BK5-800, BK5-1500

Application Example:

Model BK6 - Bellows Coupling with Conical Sleeve and Tapered Press-Fit Connection
(8 sizes with rated torque from 15-1500 Nm)

Design Description: One side conical sleeve with 6 fastening screws ISO 4762 and 3 draw-off threads. One side with backlash-free tapered conical sleeve with press-fit connection and draw-off screws. For axial mounting. Easy mounting and dismounting. Wear-free press-fit connection. Electrically and thermally insulated.

Bore Diameters: Inch or metric bores from 10 - 72 mm, or 0.50 - 2.75 inches. Keyways are not available on this model.

Options: Single position or multi-position configurations.

Sizes: BK6-15, BK6-30, BK6-60, BK6-150, BK6-300, BK6-500, BK6-800, BK6-1500

Application Example:

Model BK7 - Bellows Coupling with Expanding Shaft
(5 sizes with rated torque from 15-300 Nm)

Design Description: An expandable male shaft incorporated with a bellows coupling with clamping hub. For hollow shaft mounting. Suited for space restricted installations. Easy mounting.

Bore Diameters: One side with inch or metric bores from 8 - 60 mm, or 0.3125 - 2.25 inches. Second side has shaft diameters from 13 - 60 mm, or 0.50 - 2.25 inches. Keyways are available on bore side, but not necessary.

Sizes: BK7-15, BK7-30, BK7-60, BK7-150, BK7-300

Application Example:

Model BK8 - Compact Version with Flange and Clamping Hub for Robot Gears
(5 sizes with rated torque from 15-1500 Nm)

Design Description: One side with a single radial clamping screw on one hub ISO 4762. The other side with flange-connection and a separate intermediate flange. Compact design and easy to assemble. Corrosion resistant. Suited for space restricted installations.

Bore Diameters: One side with inch or metric bores from 12 - 80 mm, or 0.55 - 3.125 inches. Keyways are available on bore side, but not necessary. Second side with standard ISO flange dimensions.

Sizes: BK8-15, BK8-60, BK8-150, BK8-300, BK8-1500

Application Example:

What's Next?
Email Your Application
Download These Catalogs
Download CAD Drawings
Download Coupling Overview

Why Choose DieQua?

Have Any Questions?
Call Us: 630-980-1133

Quick Assist:
Installation & Maintenance Instructions
Application Examples

Stay In Touch
Join DieQua On Facebook
Follow DieQua On Twitter
See DieQua On YouTube

Related Products:
Bellows Couplings
Elastomer Insert Couplings
Miniature Couplings
Torque Limiters
Line Shafts

Coupling Overview:

Download Coupling Overview
PDF - 384KB


Optional: Bellows Couplings made of Stainless Steel


Sample Applications:
Assembly Machinery
Automated Plants
CNC Milling/Grinding
Industrial Robots
Linear Actuators
Machine Tools
Manipulators
Metal Cutting Machinery
Packaging Machinery
Printing Machinery
Robotic Axes
Servo Drives
Textile Machinery
Woodworking Machinery
and more...

180 Covington Drive
Bloomingdale, IL 60108-3105
Phone: 630-980-1133 Fax: 630-980-1232

Copyright © 2014 DieQua Corporation
Request Info or Email Directory
Read our Privacy Policy