DN125 EPDM Rubber Compensator with Integrated Carbon Steel Flanges (4.0 MPa)

SKU: WCR-DN125-EPDM-PN40-CS-59

Model TypeWCR-Hand Built
Size(DN)DN125(5inch)
Pressure Rating4MPa
Bellow MaterialEPDM Rubber
Flange MaterialGalvanized Carbon Steel
Temperature Range0℃~80℃
Working MediumWater
Length160mm
SealingFull-Face Sealing
Connection TypeFlange Connection
StructureSingle Arch
BrandSONGJIANGFLEX

Product Description & Specifications

DN125 Hand-Built EPDM Single-Arch Rubber Compensator for 4.0 MPa High-Pressure Systems

Product Overview 

This product is a DN125 EPDM rubber compensator featuring a continuous winding single-arch mechanical configuration.
The winding production process ensures a cross-sectional wall thickness profile without structural knit lines. This design avoids the inner layer separation and uneven stress accumulation common in traditional compression-molded bellows when subjected to pressure fluctuations.
The primary function of this engineering component is to mitigate mechanical vibration, isolate structure-borne acoustic waves, and absorb axial and lateral geometric displacements within rigid piping configurations.
Engineered specifically for water transport infrastructure, it operates under a nominal working pressure of 4.0 MPa within a continuous fluid temperature range of 0°C to 80°C.
The single-arch geometry provides high pressure-holding capacity per unit volume, while the integrated limit rod assembly restricts structural elongation, transferring hydraulic thrust directly through the high-tensile fasteners to protect adjacent pump casings and valve bodies.

Key Engineering Features 

    • Continuous Winding Arch Geometry
      Elimidates localized internal stress concentrations by maintaining uniform cord reinforcement alignment throughout the flexible bellows, preventing localized matrix shearing under cyclic pressure loading.
    • Full-Face Vulcanized Sealing Profile
      The EPDM elastomer matrix is bonded directly across the entire seating surface of the carbon steel flange during the thermal vulcanization cycle, preventing gasket displacement, cold flow, or high-pressure bypass leakage.
    • High-Elasticity EPDM Formulation
      Maintains cross-linked polymeric integrity under continuous hydraulic immersion between 0°C and 80°C, providing constant damping coefficients for low-frequency structural piping vibrations.
    • Pre-Set Control Rod Displacement Limiters
      Mechanically constrains axial expansion limits during pressure spikes, neutralizing hydrostatic thrust and safeguarding down-line flange connections from structural over-extension failure.

Applications 

  • High-Head Pump Discharges: Installed on the output side of high-lift centrifugal pumps to absorb fluid pulsations, damp mechanical resonance, and prevent transmission of acoustic energy into the header system.
  • High-Pressure Fluid Transfer Lines: Integrated into water distribution mains operating at up to 4.0 MPa to accommodate natural ground subsidence and thermal expansion differentials without dropping line pressure.
  • Commercial HVAC Hydronic Loops: Positioned within large-bore chilled and condenser water lines to absorb cyclical thermal displacement during seasonal plant start-up and shutdown phases.
  • Industrial Utility Intake Piping: Applied at the connection interfaces of heavy water-cooling loops and filtration arrays to isolate equipment vibrations from structural pipe racks.

Technical Specifications

ParameterValue
Nominal Diameter125(5inch)
Working Pressure4MPa
Test Pressure6MPa
Blast Pressure12MPa
Axial Extension5mm
Axial Compression10mm
Lateral Deflection10mm
Angular Deflection5°
Flange StandardGB/T 9124.1-2019
Flange Outer Diameter (O.D.)270mm
Pitch Circle Diameter (PCD)220mm
Number of Bolt Holes8pcs
Bolt Hole Diameter26mm
Flange Thickness20mm