Skip to main content
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.

Explore your interests

View More
All Categories
Best Seller (30)
New List (30)
Protective Case Lid for Pelican Cases - Laptop Insert for Models 1510, 1560, and 1535

Protective Case Lid for Pelican Cases - Laptop Insert for Models 1510, 1560, and 1535

$254.00

Universal 5800 Super Glue for Plastic, Metal, Glass, and Wood, 10-Second Fast Curing

Universal 5800 Super Glue for Plastic, Metal, Glass, and Wood, 10-Second Fast Curing

$2.01

White Noise Wood Chip Core Grid Scented Candle Wooden Core S-Type Brand Name Candle Container Soy Candle Core Wood

White Noise Wood Chip Core Grid Scented Candle Wooden Core S-Type Brand Name Candle Container Soy Candle Core Wood

$1.50

Zunjue 100% Cotton Paper Block 300g Watercolor Paper, Fine/Medium Grain, Thickened 80 Sheets, Neutral Acid-Free Journal Paper for Art Students, Beginners, Watercolor, Colored Pencil, Pen, Light Wash, Marker

Zunjue 100% Cotton Paper Block 300g Watercolor Paper, Fine/Medium Grain, Thickened 80 Sheets, Neutral Acid-Free Journal Paper for Art Students, Beginners, Watercolor, Colored Pencil, Pen, Light Wash, Marker

$27.20

Outdoor Waterproof Dry Bag for Rafting and Creek Walking - Large Capacity Backpack for Swimming, Hiking, Diving, and Flood Rescue

Outdoor Waterproof Dry Bag for Rafting and Creek Walking - Large Capacity Backpack for Swimming, Hiking, Diving, and Flood Rescue

$132.00

Lukang 995 Door and Window Fast-Drying Glass Sealant - Transparent Weather-Resistant Neutral Silicone Structural Adhesive

Lukang 995 Door and Window Fast-Drying Glass Sealant - Transparent Weather-Resistant Neutral Silicone Structural Adhesive

$222.90

Large Flip-Type Water Draining and Air Drying Machine, Fully Automatic Air Knife Blower for Vegetables, Commercial Continuous Drying Equipment

Large Flip-Type Water Draining and Air Drying Machine, Fully Automatic Air Knife Blower for Vegetables, Commercial Continuous Drying Equipment

$15,282.00

Large Capacity Household Quilt Storage Bag - Waterproof and Moisture-Proof Duvet Organizer for Moving, Packing, and Luggage Sorting

Large Capacity Household Quilt Storage Bag - Waterproof and Moisture-Proof Duvet Organizer for Moving, Packing, and Luggage Sorting

$5.88

Scented Candle Aluminum Alloy Turntable 360-Degree Rotating Double-Sided Silent Non-Slip Small Turntable for Cake Decorating and DIY

Scented Candle Aluminum Alloy Turntable 360-Degree Rotating Double-Sided Silent Non-Slip Small Turntable for Cake Decorating and DIY

$30.40

Ceramic Five Oxen Painting Brush Washer – Antique-Style Ink Well for Calligraphy & Traditional Painting

Ceramic Five Oxen Painting Brush Washer – Antique-Style Ink Well for Calligraphy & Traditional Painting

$16.90

Liupintang 3-in-1 Brush Washing Bucket with Palette - Portable Handheld Multi-Function Art Tool for Chinese Painting, Watercolor, and Gouache, Foldable Small Pail

Liupintang 3-in-1 Brush Washing Bucket with Palette - Portable Handheld Multi-Function Art Tool for Chinese Painting, Watercolor, and Gouache, Foldable Small Pail

$17.80

ZGT Type Damped Spring Vibration Isolator for Large Equipment such as Chillers and Diesel Generator Sets

ZGT Type Damped Spring Vibration Isolator for Large Equipment such as Chillers and Diesel Generator Sets

$135.00

Shanlian Lake Brush Wool Felt Mat for Calligraphy and Painting, Washable Desk Pad for Beginners

Shanlian Lake Brush Wool Felt Mat for Calligraphy and Painting, Washable Desk Pad for Beginners

$22.70

New Silicone Data Cable Protector, Anti-Break and Anti-Bite Cord Organizer for Charging Lines and Headphones, Universal Phone Accessory

New Silicone Data Cable Protector, Anti-Break and Anti-Bite Cord Organizer for Charging Lines and Headphones, Universal Phone Accessory

$5.58

Cafeteria Bulb Vegetable Cutter - Complete Kelp Shredding Production Line, All-in-One Slicing, Dicing, and Shredding Machine

Cafeteria Bulb Vegetable Cutter - Complete Kelp Shredding Production Line, All-in-One Slicing, Dicing, and Shredding Machine

$10,000.00

Electric Water Dispenser Pump for Bottled Mineral Water - Automatic Press-Type Purified Water Pump Manufacturer

Electric Water Dispenser Pump for Bottled Mineral Water - Automatic Press-Type Purified Water Pump Manufacturer

$113.00

Heavy-Duty Industrial Wiping Cloths for Auto Painting, Baking, Film Application, Detailing, and Degreasing – Absorbent, Oil-Removing, Lint-Free Paper and Cloth

Heavy-Duty Industrial Wiping Cloths for Auto Painting, Baking, Film Application, Detailing, and Degreasing – Absorbent, Oil-Removing, Lint-Free Paper and Cloth

$120.00

6-Cavity Oval Beehive Silicone Mold for DIY Handmade Soap - Heat-Resistant Non-Stick Large Mold for Milk and Essential Oil Soaps

6-Cavity Oval Beehive Silicone Mold for DIY Handmade Soap - Heat-Resistant Non-Stick Large Mold for Milk and Essential Oil Soaps

$4.93

Data Cable Organizer Bag with Zipper for Charging Cables and Adapters - Dustproof Desktop Storage

Data Cable Organizer Bag with Zipper for Charging Cables and Adapters - Dustproof Desktop Storage

$5.90

Auby Baby Rattle Toy for 6+ Months, Chewable Wave Drum and Shaker for Newborns and Toddlers

Auby Baby Rattle Toy for 6+ Months, Chewable Wave Drum and Shaker for Newborns and Toddlers

$24.90

Preferred 45L Industrial Pulping Machine Spinach Fresh Pulp Galangal Carrot Tomato Sauce Making Fruit and Vegetable Industry Blender

Preferred 45L Industrial Pulping Machine Spinach Fresh Pulp Galangal Carrot Tomato Sauce Making Fruit and Vegetable Industry Blender

$7,632.00

KAD Professional Thickened Sketch Blending Stump - Dual-Head Smudging Pen for Art Students

KAD Professional Thickened Sketch Blending Stump - Dual-Head Smudging Pen for Art Students

$9.90

Beijing Imported Dental Implant Package - Appointment Booking, X-Ray, and Treatment Plan Included

Beijing Imported Dental Implant Package - Appointment Booking, X-Ray, and Treatment Plan Included

$1.00

Huahu [Top Layer Cowhide] Japanese-Style Men's Genuine Leather Belt, Simple Casual Business Wide Belt with Automatic Buckle

Huahu [Top Layer Cowhide] Japanese-Style Men's Genuine Leather Belt, Simple Casual Business Wide Belt with Automatic Buckle

$423.00

Wall-Mounted Towel Storage Box Large Capacity for Bathroom

Wall-Mounted Towel Storage Box Large Capacity for Bathroom

$8.42

Loctite 480/411/403/407/406/414/420/401/415 Heat-Resistant 495 High-Temp 417/416 Instant Adhesive

Loctite 480/411/403/407/406/414/420/401/415 Heat-Resistant 495 High-Temp 417/416 Instant Adhesive

$26.80

Ulanzi CSS1 Camera Quick-Release Shoulder Strap - Universal Anti-Slip Crossbody Belt for Fujifilm, Sony, and Canon DSLR/Mirrorless Cameras

Ulanzi CSS1 Camera Quick-Release Shoulder Strap - Universal Anti-Slip Crossbody Belt for Fujifilm, Sony, and Canon DSLR/Mirrorless Cameras

$109.00

Invisalign Retainer Storage Case Portable Travel Container for Clear Aligners Dentures Orthodontic Appliances Cleaning Q

Invisalign Retainer Storage Case Portable Travel Container for Clear Aligners Dentures Orthodontic Appliances Cleaning Q

$6.59

70*275mm Flocked Abrasive Pad Circular Backing Sanding Disc Polishing Sheet Self-Adhesive Scouring Pad Brushed Finish Cloth

70*275mm Flocked Abrasive Pad Circular Backing Sanding Disc Polishing Sheet Self-Adhesive Scouring Pad Brushed Finish Cloth

$4.05

50/100 Pairs Men's Foot Therapy Short Socks - Odor-Resistant, Low-Cut, Summer Thin, Disposable Street Market Socks

50/100 Pairs Men's Foot Therapy Short Socks - Odor-Resistant, Low-Cut, Summer Thin, Disposable Street Market Socks

$19.99