Diaphragm Coupling
Your Professional Diaphragm Coupling Supplier
Zhejiang Haineng Transmission Machinery Co., Ltd. is a high-tech enterprise specializing in the R&D, manufacturing, sales, and service of couplings and transmission systems, providing reliable transmission solutions for various industrial applications.
The company specializes in couplings and transmission systems, mainly producing diaphragm couplings, star-shaped elastic couplings, drum gear couplings, flange couplings, serpentine spring couplings, as well as universal shafts, backstops, pulleys, and other transmission products to meet diversified industrial application needs.
Why Choose us
Certified Quality & Environmental Management
Through strict compliance with GB/T 19001-2016/ISO 9001:2015 and GB/T 24001-2016/ISO 14001:2015 standards, ZG Coping ensures stable product quality, efficient production management, and environmentally responsible manufacturing practices.
Advanced Production Infrastructure
The facility is equipped with state-of-the-art manufacturing equipment, including CNC vertical and horizontal machining centers, CNC lathes, and CNC milling machines—enabling high-precision machining and complex geometric forming of critical coupling components.
Advanced Precision Manufacturing Capabilities
Leveraging 19 patented technologies and a robust engineering customization capability, the company delivers high-performance transmission solutions to key industrial sectors, including fluid machinery, industrial pumps, fans, steam turbines, compressors, and construction and engineering machinery.
Parameter
|
Parameter |
Specification |
|
Product Type |
Diaphragm Coupling (for Water Pump) |
|
Structure |
Flexible metal diaphragm type |
|
Application |
Water pumps, centrifugal pumps, industrial transmission systems |
|
Torque Transmission |
Medium to high torque capacity |
|
Misalignment Compensation |
Angular, axial, and radial misalignment compensation |
|
Transmission Efficiency |
Up to 99%+ |
|
Backlash |
Zero backlash transmission |
|
Speed Range |
Suitable for medium to high-speed operation |
|
Material |
High-strength alloy steel / stainless steel diaphragm |
|
Maintenance |
Maintenance-free design |
|
Installation |
Easy installation and disassembly |
(1) Strong ability to compensate for misalignment of two shafts, with double the angular displacement compared to gear couplings, minimal reaction force during radial displacement, high flexibility, allowing for certain axial, radial, and angular displacement.
(2) Significant damping effect, no noise, no wear.
(3) Suitable for working in high temperatures (-80 to +300 degrees Celsius) and harsh environments, capable of safe operation under impact and vibration conditions.
(4) High transmission efficiency, up to 99.86%. Particularly suitable for medium and high-speed high-power transmission.
(5) Simple structure, lightweight, small size, easy installation and disassembly. Can be disassembled without moving the machinery (referring to the type with an intermediate shaft), no lubrication required.
(6) Accurate transmission of speed, no slippage during operation, suitable for precision mechanical transmission.
Combination of Diaphragm Couplings
Diaphragm Disc: The contoured metal disc that flexes to accommodate misalignment while transmitting torque from bore to rim. Typical materials are AISI 4340 or 17-4 PH stainless, hardened to 35–40 HRC. Thickness profile runs roughly 1.5 mm at the rim to 6–10 mm at the hub, machined to a manufacturer-specific curve that equalises bending stress.
Drive Hub: The hub bolted or shrink-fit to the driving shaft. The diaphragm rim attaches to this hub via a precision bolt circle, typically 8 to 24 fitted bolts torqued to a controlled value — often 70–90% of yield to maintain joint stiffness at speed. Pilot fits run H7/h6 to keep runout under 0.025 mm.
Spacer Tube: The tube that connects the two diaphragms across the BSE (between shaft ends) gap. On API 671 couplings the spacer also acts as the flying piece — if a diaphragm fails, the spacer is captured by anti-flail features so it doesn't exit the coupling guard. Spacer length is typically 100–600 mm depending on the train.
Driven Hub: Mirror of the drive hub on the driven shaft side. Match-balanced as a complete assembly to ISO 1940 G2.5 or better — anything looser and you'll see vibration spikes above 8,000 RPM.
Diaphragm Pack (Multi-Disc Variant): Some designs stack 2 to 8 thinner diaphragms instead of using one contoured disc. Each disc is 0.3–0.6 mm thick. Stacking lets a smaller OD coupling handle more axial travel, but the pack adds a slip-plane risk if the discs fret against each other.
Anti-Flail Provision: Required by API 671 for refinery service. If a diaphragm fractures at full speed, the spacer would otherwise become a projectile inside the guard. Anti-flail rings or captured shoulders contain the fragments and let the operator coast the train down safely.
(1) The gap between the two halves of the coupling is too wide, causing the diaphragm to experience significant axial force, resulting in wear of the serration hole or serration bolt, leading to abnormal noise.
(2) Excessive axial offset or deflection angle of the two halves of the coupling can also cause vibration and abnormal noise during equipment operation.
(3) Differences in speed between the driving end and the driven end can also cause vibration and abnormal noise during equipment operation.
(4) Malfunction of the speed encoder of the motor, causing the motor's speed to fluctuate, resulting in abnormal noise in the diaphragm coupling.
Application of Diaphragm Coupling
Turbomachinery
Supports accurate torque transmission in high-speed rotating equipment
Oil and gas
Helps manage misalignment and torque loads in pumps and compressors
Power generation
Enables stable power transmission in turbine generator systems
Wastewater
Maintains reliable operation in centrifugal and potable water pump
Certificate
Flexible Global Shipping Solutions
We support multiple shipping methods including sea freight, air freight, rail transportation, and express delivery to meet different delivery timelines and project requirements. Professional packaging and export handling ensure safe and efficient transportation for international orders.
FAQ