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Home / Couplings / DJM Single Diaphragm Coupling 45# Steel, SJM Double Diaphragm Stainless Steel Expansion Sleeve Type Elastic Servo Motor Coupling

Attributes

Brand -
Category Standard Parts, Components & Industrial Consumables / Couplings
Origin -
Material 45# Steel / Stainless Steel
Coupling Type Diaphragm / Expansion Sleeve
Application Servo Motor Systems
Torque Capacity High Torque Transmission
Speed Rating High Speed Operation
Misalignment Compensation Angular, Parallel, and Axial
Backlash Zero Backlash Design
Operating Temperature -20°C to +120°C
Surface Treatment Black Oxide / Polished
Installation Method Clamping Screw Fixation

6 reviews

A

Anonymous

Mar 19, 2026

Rating: 4/5

Good value for money

Compared to imported brands, these offer similar performance at a better price point. The packaging was secure, and all mounting screws were included.

A

Anonymous

Mar 17, 2026

Rating: 5/5

Excellent torque transmission

No slippage even under heavy load startups. The diaphragm design absorbs shock loads effectively, protecting our sensitive encoder equipment.

A

Anonymous

Mar 09, 2026

Rating: 5/5

Durable and reliable

Running these in a dusty industrial environment for six months now with no signs of wear. The 45# steel construction holds up well against minor impacts and debris.

A

Anonymous

Mar 09, 2026

Rating: 4/5

Great quality, slightly tight fit

The build quality of the stainless steel version is excellent. It took a bit more effort to install due to the tight tolerance on the expansion sleeve, but once seated, it is rock solid.

A

Anonymous

Mar 05, 2026

Rating: 5/5

Solved our alignment issues

We had persistent wear issues with old jaw couplings. Switching to this diaphragm type allowed us to accommodate slight misalignments without transferring stress to the motor bearings. Game changer.

A

Anonymous

Mar 01, 2026

Rating: 5/5

Perfect for high-speed servo applications

Installed these on our CNC milling machine spindles. The zero backlash is noticeable immediately, and the vibration levels have dropped significantly. Highly recommended for precision work.

5 FAQ

Q: What is the maximum allowable angular misalignment for the SJM series?

A: The SJM Double Diaphragm series typically allows for up to 1.5 degrees of angular misalignment, depending on the specific model size.

Q: Are replacement diaphragms available if they get damaged?

A: The diaphragm is an integral part of the assembly for optimal balance. In case of damage, we recommend replacing the entire coupling unit rather than individual components.

Q: How do I determine the correct bore size for my motor shaft?

A: Please refer to the detailed dimension chart in the product manual. You can also contact our support team with your motor model number for a precise recommendation.

Q: Can I use the 45# Steel version in a humid environment?

A: While the 45# Steel has a protective coating, we recommend the Stainless Steel (SJM) version for highly humid or corrosive environments to ensure long-term durability.

Q: Does this coupling require lubrication during operation?

A: No, the diaphragm design is maintenance-free and does not require any lubrication, making it ideal for clean environments.

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