HVAC DN65 Double Sphere Rubber Expansion Joint

Product Overview

As a premier manufacturer and supplier of advanced piping components, we offer this high-performance dual-sphere flexible connector engineered for demanding fluid handling systems. Designed to protect critical infrastructure, this component delivers exceptional reliability for large-scale procurement and industrial engineering needs.

• Engineered for superior multi-directional movement absorption.
• Constructed with premium reinforced elastomers for extended longevity.
• Precision-machined flanges ensuring a flawless, leak-proof seal.
• Optimized for severe thermal and mechanical stress environments.

Product Description

Step into any high-capacity pump room, and the aggressive hum of mechanical vibration is immediately apparent. Our double-sphere flexible connectors are meticulously engineered to silence that chaos. When you run your hands over the dense, vulcanized exterior of this joint, you can feel the structural integrity born from advanced molding techniques. The smooth, seamless inner bore is designed to facilitate unrestricted fluid flow, eliminating turbulence while resisting the abrasive bite of harsh media. By isolating mechanical noise and absorbing the violent shockwaves of water hammer, this connector acts as a critical buffer between your high-value rotating equipment and the rigid piping network. The robust weight of the solid steel flanges, coated for absolute corrosion resistance, speaks to the uncompromising craftsmanship poured into every unit. It does not merely connect two pipes; it actively preserves the lifespan of your entire system by gracefully yielding to thermal expansion, contraction, and unpredictable ground settlement. This is not just a replacement part; it is a proactive defense mechanism for your most critical fluid infrastructure.

Product Specifications

Key Features & Highlights

Modern fluid dynamics require components that do more than just bridge a gap. Our flexible connectors are engineered to actively enhance system stability, reduce maintenance overhead, and ensure operational safety across complex industrial networks.

• Exceptional Fatigue Resistance: The dual-arch geometry distributes mechanical stress evenly across the elastomer body, preventing localized wear and dramatically extending the operational lifespan even under continuous dynamic loading.
• Acoustic and Kinetic Dampening: By breaking the rigid acoustic bridge of metal piping, the dense rubber matrix absorbs high-frequency vibrations and low-frequency shocks, creating a noticeably quieter and safer working environment.
• Flawless Sealing Integrity: The precision-molded sealing face eliminates the need for additional gaskets, providing a secure, leak-proof barrier that holds firm even under fluctuating pressure spikes.
• Simplified Maintenance: The lightweight, highly elastic nature of the component allows for effortless alignment during installation, significantly reducing labor hours and minimizing costly system downtime.

Core Engineering & Performance Dimensions

Structural Design & Movement Compensation

The defining characteristic of this connector is its advanced double-sphere architecture. Compared to traditional single-sphere models, the dual-arch design offers an exponentially higher degree of flexibility. It is specifically engineered to absorb a massive spectrum of axial compression, axial extension, lateral deflection, and angular torsion. When pipelines shift due to severe thermal fluctuations or unexpected foundation settlement, this joint acts as a forgiving pivot point. By accommodating these extreme misalignments, it prevents catastrophic fatigue fractures in rigid pipes and protects delicate valve housings from warping.

Vibration Absorption & Noise Reduction

In high-velocity HVAC networks, compressor stations, and heavy-duty pump rooms, mechanical vibration is the enemy of longevity. This elastomeric joint serves as a supreme acoustic and kinetic isolator. It effectively severs the transmission path of mechanical resonance and devastating water hammer impacts. By acting as a shock absorber, it buffers high-value pumps, chillers, and compressors from the destructive forces of their own operation, drastically reducing ambient noise levels and safeguarding your capital equipment investments.

Material Versatility & Media Compatibility

Fluid handling environments are rarely uniform, which is why we offer a comprehensive suite of premium rubber compounds. The inner and outer layers can be customized with EPDM for chilled water and HVAC applications, NBR for aggressive oil and petroleum-based media, or FKM for extreme temperature and highly corrosive chemical environments. Beneath this resilient surface lies a tightly woven nylon fabric reinforcement, further fortified by a high-tensile steel wire skeleton. This multi-layered construction guarantees absolute chemical stability and structural integrity, regardless of the fluid passing through it.

Pressure & Temperature Tolerance

Engineered for the most demanding operational extremes, this connector boasts a formidable maximum working pressure of 2.5 MPa, with a rigorous test pressure of 1.5 times and a burst pressure threshold reaching 4 times the working limit. Furthermore, it maintains structural stability under a vacuum resistance of 44.9 KPa (350 mmHg). Capable of operating flawlessly in a wide temperature range from -20 ºC to 100 ºC, it is the definitive choice for high-rise building water distribution, district heating, and severe industrial processing networks.

Flange Standards & Installation

Global compatibility is engineered directly into the product. The robust metal flanges can be drilled to meet any major international standard, including DIN, JIS, GOST, and ANSI. Procurement teams can select from zinc-plated carbon steel, surface-sprayed finishes, or premium SS304/SS316 stainless steel to match specific environmental demands. The compact, lightweight design facilitates rapid, low-effort installation in confined spaces. For installations lacking proper anchoring, the system seamlessly integrates with heavy-duty control units and tie rods to prevent over-extension and ensure absolute operational safety.

Wide Industry Applications

Versatility is paramount for large-scale procurement and engineering design. While it excels in commercial HVAC and municipal water treatment facilities, its rugged construction allows it to thrive in far more aggressive sectors. This joint is heavily utilized in petrochemical processing, marine shipbuilding, desalination plants, paper mills, and power generation facilities. It is the ultimate universal solution for mitigating stress in any complex, high-capacity fluid transport network.

Quality Control & Certifications

Reliability is never left to chance. Every single unit undergoes a rigorous, multi-stage quality assurance protocol before it leaves the factory floor. From ultrasonic thickness testing of the rubber walls to high-pressure hydrostatic burst tests, our manufacturing process is governed by strict ISO 9001 quality management systems. Built to align with stringent international benchmarks like CE and WRAS for potable water safety, this component guarantees world-class durability, providing engineers and project managers with absolute peace of mind.

Why Choose Us

Partnering with a dedicated manufacturer means securing a direct line to uncompromising quality and technical expertise. We do not just assemble components; we engineer long-term reliability for your most critical infrastructure.

• Proprietary Mold Ownership: By designing and maintaining our own advanced molds, we guarantee precise dimensional accuracy, superior wall thickness uniformity, and a stronger pressure-bearing capacity than standard market alternatives.
• End-to-End Quality Assurance: From raw elastomer compounding to final flange machining, every step of the manufacturing process is strictly monitored under international quality management protocols, ensuring zero-defect deliveries.
• Unmatched Customization: We understand that no two projects are identical. Our engineering team offers bespoke solutions, adapting rubber compounds, flange materials, and drilling standards to perfectly match your unique environmental and fluid requirements.
• Streamlined Global Supply: Operating as a direct factory source, we eliminate intermediary delays, providing highly competitive pricing, scalable production volumes, and rapid fulfillment for time-sensitive global projects.

Frequently Asked Questions (FAQ)

Below are detailed answers to common technical inquiries regarding our elastomeric pipeline connectors to assist your engineering and procurement teams.

• How does the double-sphere design outperform single-sphere alternatives?
  The dual-arch geometry provides a significantly larger surface area for stress distribution. This allows the joint to absorb a much wider range of axial, lateral, and angular movements without compromising the structural integrity of the rubber, resulting in a much longer service life under extreme dynamic conditions.
• What media can the different elastomer variants safely handle?
  Our standard EPDM is highly resistant to ozone, weathering, and hot/cold water, making it ideal for HVAC. NBR is specifically formulated for environments involving oils, lubricants, and petroleum-based fluids. For highly aggressive chemicals and elevated temperatures, our FKM (fluoroelastomer) option provides unparalleled chemical resistance.
• When are control units (tie rods) mandatory for installation?
  Control units must be installed whenever the piping system is not properly anchored or guided, or when the system pressure exceeds the structural limits of the unanchored joint. They act as a fail-safe to prevent the joint from over-extending (pulling apart) due to excessive thrust forces generated by internal pressure.
• How does operating temperature affect the maximum working pressure?
  The stated maximum working pressure of 2.5 MPa is calibrated for an ambient operating temperature of 30 ºC. As the temperature of the fluid increases toward the 100 ºC limit, the elastomer naturally softens, which proportionally reduces the maximum safe pressure rating. Consult our technical charts for specific temperature-to-pressure derating curves.
• Can the flange connections be customized to fit older piping infrastructure?
  Absolutely. Because we maintain our own machining facilities, we can drill flanges to match any historical or international standard (DIN, ANSI, JIS, GOST). We can also accommodate custom bolt-hole patterns and specific material requests, such as SS316 for highly corrosive external environments.