Ductile Iron Back-Up Rings | IPS & DIPS | SDR 7–11

Ductile Iron Back-Up Rings | IPS & DIPS | SDR 7–11

Integrity Fusion Ductile Iron Back-Up Rings provide a durable, pressure-rated flange connection for IPS and DIPS HDPE pipelines used across municipal, industrial, and commercial infrastructure. Manufactured from ASTM A536 Grade 65-45-12 ductile iron, these rings deliver long-term strength and are fully compatible with standard HDPE flange adapters.

Epoxy-coated rings use a premium fusion-bonded epoxy coating for superior corrosion resistance, while select sizes are also offered in a red oxide primer finish. Most sizes 12" and below meet FM Approval requirements—FM 200 for SDR 11 and FM 335 for SDR 7–9.

Key Features & Benefits

• High-Strength Ductile Iron – Made from ASTM A536 Grade 65-45-12 for demanding pressure applications
• Compatible with SDR 7–11 – Suitable for IPS and DIPS HDPE flange adapter systems
• Epoxy-Coated & Red Oxide Options – Corrosion-resistant finishes for buried or exposed installations
• FM Approved (Selected Sizes) – SDR 11 meets FM 200; SDR 7–9 meet FM 335
• Class 150 Bolt Pattern – Manufactured to ANSI/ASME B16.5 & AWWA C207 specifications

Applications

• Municipal water & wastewater systems
• Industrial HDPE pipelines and mechanical transitions
• Pump stations, treatment facilities, and valve rooms
• Fire protection systems (FM Approved sizes)
• Agricultural, geothermal, mining, and utility installations

Epoxy vs. Red Oxide Coating – Key Differences

Epoxy-Coated Backup Rings use a fusion-bonded epoxy (FBE) finish designed for maximum corrosion resistance and long-term performance. Recommended for:

• Direct-bury / underground installations
• Wet, corrosive, or chemical exposure environments
• Municipal and industrial pressure systems
• Projects requiring the longest coating life

Red Oxide Primer Backup Rings use a durable, economical protective primer suited for:

• Above-grade interior service
• Dry or low-moisture environments
• Budget-conscious applications
• General purpose mechanical connections

Both finishes provide reliable protection, but epoxy-coated rings are preferred for buried service or any installation subject to moisture or corrosion.

Available Options

• Sizes: 2"–36" (IPS) and 4"–12" (DIPS)
• SDR Ratings: SDR 7, SDR 9, SDR 11
• Finishes: Epoxy-Coated or Red Oxide Primer

See product variants above for exact SDR compatibility, material type, and item code.

Specification Summary