Steel Backing Ring for HDPE Stub Flange

Core Parameters

• Size –DN63-1200mm (Can Be Customized)

  Pressure rating : SDR11-PN16 Bar, SDR13.6-PN12.5 Bar, SDR17-PN10 Bar, SDR21-PN6 Bar, SDR26-PN6 Bar

  Raw materials:High Quality PE80 Or PE100 Raw Materials

  Supply capacity: 3 × 40 feet per week container.

  Certificate:ISO 14001, ISO 9001, OHSAS 18001, CE BS EN 12001 Certification

  The backing ring slides over the HDPE pipe before the stub flange is welded to the pipe. After installation, the steel ring sits behind the HDPE stub flange collar and distributes the bolt load evenly around the connection. This provides the mechanical strength needed for a secure bolted joint without applying excessive stress directly to the HDPE component.

  
  Available in carbon steel or stainless steel, our backing rings can be supplied with PN10 or PN16 drilling patterns and customized dimensions according to project requirements.

  Factory pricing. Global compliance. Ready to supply. Get your quote.

  

• A Steel Backing Ring is a loose metal flange used with an HDPE stub flange to form a bolted, detachable pipeline connection. Unlike a welded HDPE joint, this flange connection can be dismantled when maintenance, inspection, valve replacement or equipment connection is required.

  
  The steel backing ring does not contact the conveyed medium directly in a typical stub-flange assembly. Its function is to provide the required bolt-hole pattern and distribute tightening forces evenly onto the HDPE stub flange collar. A suitable gasket is positioned between the mating flange faces to create the seal.

  
  Steel backing rings are widely used where HDPE pipelines connect to pumps, valves, meters, steel pipes, tanks, manifolds or other mechanical equipment.

   

  

Product Features

• • ✅Designed for HDPE stub flange and flange adaptor connections
  • ✅Provides mechanical support for bolted HDPE flange joints
  • ✅Available in PN10 and PN16 pressure classes
  • ✅Carbon steel and stainless steel material options
  • ✅Hot-dip galvanized, zinc-plated, epoxy-coated or nylon-coated finishes available
  • ✅Standard and customized drilling patterns available
  • ✅Suitable for connection to valves, pumps, tanks and metal pipelines
  • ✅Allows convenient dismantling for maintenance and replacement
  • ✅Available for HDPE pipe sizes from DN/OD 63 mm to 1200 mm
  • ✅Export packaging and OEM marking available on request

Please send your request to the email address:sales@mfgpipe.com (We will respond to you within 24 hours).

Technical Specifications

Applications

Steel Backing Rings are suitable for:

• ✅HDPE water supply pipelines
• ✅Irrigation and agricultural systems
• ✅Gas and industrial pipeline systems, subject to project requirements
• ✅Pump and valve connections
• ✅Tank, vessel and manifold connections
• ✅Mining and slurry pipeline systems
• ✅Water-treatment and wastewater projects
• ✅Pipeline expansion, repair and maintenance work
• ✅Flanged connections between HDPE pipe and steel or ductile-iron pipelines

How the Flange Assembly Works

• A typical HDPE flange connection consists of:

  1. 1. HDPE pipe
  2. 2. Steel backing ring
  3. 3. HDPE stub flange or flange adaptor
  4. 4. Rubber gasket
  5. 5. Mating flange, valve, pump or equipment connection
  6. 5. Bolts, nuts and washers

  The backing ring should be installed onto the HDPE pipe before the stub flange is butt-fused to the pipe. After the fusion joint cools, the backing ring is moved into position behind the stub flange collar. A compatible gasket is then placed between the two flange faces, and the bolts are tightened evenly in a cross pattern.

Installation Guidelines

• ✅Confirm that the backing ring, stub flange and mating flange use the same pressure class and drilling pattern.
• ✅Slide the backing ring over the HDPE pipe before welding the stub flange.
• ✅Butt-fuse the HDPE stub flange to the pipe according to approved welding procedures.
• ✅Allow the fusion joint to cool completely.
• ✅Position the backing ring behind the stub flange collar.
• ✅Place a compatible gasket between the flange sealing faces.
• ✅Align the bolt holes with the mating flange.
• ✅Insert bolts, nuts and washers.
• ✅Tighten bolts gradually in a star or cross pattern to distribute load evenly.
• ✅Do not over-tighten bolts, as excessive force may damage the HDPE stub flange or gasket.

Why Choose Our Steel Backing Rings?

• ✅Compatible with common HDPE flange connection systems
• ✅Strong mechanical support for bolted joints
• ✅Flexible material and coating options
• ✅PN10 and PN16 drilling patterns available
• ✅Customized standards for international projects
• ✅Suitable for water, irrigation, industrial and mining applications
• ✅Convenient for maintenance, replacement and future pipeline modification
• ✅Reliable export packaging and responsive technical support

Frequently Asked Questions

What is a steel backing ring used for?

It is used with an HDPE stub flange or flange adaptor to create a strong, detachable bolted connection between HDPE pipe and flanged equipment.

Is the backing ring the sealing component?

No. The backing ring provides mechanical support and bolt-hole alignment. The seal is created by the HDPE stub flange faces and a suitable gasket.

Can a backing ring be reused?

It may be reused if it is free from corrosion, deformation, cracks and damaged bolt holes. The HDPE stub flange itself is normally permanently welded to the pipe.

What is the difference between PN10 and PN16?

PN10 and PN16 refer to different nominal pressure classes and have different flange dimensions or drilling requirements in some sizes. Confirm the required standard before ordering.

Which surface finish should I choose?

Hot-dip galvanizing is commonly used for general outdoor service. Epoxy or nylon coatings can be considered for additional corrosion protection. Stainless steel is suitable for corrosive or marine environments, subject to grade confirmation.

Please send your request to the email address:sales@mfgpipe.com (We will respond to you within 24 hours).

Request a Quote

Please provide the following information:

• ✅HDPE pipe OD and stub flange size
• ✅Required pressure class: PN10 or PN16
• ✅Required drilling standard
• ✅Material: carbon steel or stainless steel
• ✅Required surface finish
• ✅Quantity and destination port
• ✅Drawing, bolt-hole pattern or project specification if available

Contact us today for drawings, samples, technical support and quotation.

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