How to Repair Corroded Pipework With High Temp Epoxy Solutions

Corroded pipework operating at elevated temperatures presents a significant maintenance challenge, particularly where corrosion has resulted in thin wall or through-wall defects. Factors such as aggressive process media, thermal cycling, and restricted access often make conventional repair methods such as welding or pipe replacement costly, disruptive, and difficult to execute safely.

In these situations, high temperature epoxy solutions provide a practical, engineered repair solution. When combined with composite reinforcement systems, high temperature epoxy materials can be used to restore wall thickness, rebuild damaged areas, and provide long-term corrosion protection, without hot work and with minimal downtime.

Why High-Temperature Pipework Fails in the Mining Industry

In mining and smelting operations, pipework selection is driven by pressure, temperature, abrasion, and corrosion resistance. Common materials include:

• Carbon steel
  • High temperature and pressure resistance
  • Strong and durable
  • Cost‑effective
  • Wear resistant
  • Suitable for heavy machinery and structural applications
• HDPE (High Density Polyethylene)
  • Corrosion‑proof
  • Chemical resistant
  • Flexible
  • Lightweight

As a result, carbon steel remains the dominant material for critical high-temperature mining pipework.

Step-by-step Guide – How to Repair a Corroded Pipework with High Temperature Epoxy Solutions

This article provides a step-by-step guide to repairing corroded pipework using high temperature epoxy solutions, based on a real application on a steam condenser header operating in elevated temperature service.

To ensure effective pipe repair, restore wall thickness, and deliver long-term corrosion protection at high temperatures, a repair system was selected comprising Belzona’s high-strength composite wrap Belzona SuperWrap II and pre-rolled doubler plates, cold bonded to the pipe using Belzona 1511 (Super HT-Metal), a high temperature epoxy repair composite.

Step 1: Surface Preparation

Both the doubler plates and corroded pipe repair areas were grit-blasted to achieve SSPC-SP10 / NACE 2 / Sa 2 ½ (Near White Metal) with a 3 mil (75 µm) anchor profile. All surfaces were then cleaned with a cleaner/degreaser) to ensure optimal cleanliness.

Step 2: Hole Patching – Belzona SuperWrap II

Belzona SuperWrap II reinforcing sheets were pre‑cut and coated with Belzona SuperWrap II (1983 Resin). These layers were then applied to the affected areas of the header pipes and consolidated using a roller.

Step 3: Overcoating with Belzona 1593 High Temperature Epoxy Coating

After the Belzona SuperWrap II patches had reached the appropriate overcoating stage, Belzona 1593, a high temperature epoxy coating designed to deliver long term corrosion and chemical resistance to equipment operating under continuous immersion up to 160°C (320°F), was applied over the Belzona SuperWrap ll patches to provide enhanced chemical protection.

Step 4: Cold Plate Bonding with Belzona 1511 (Super HT-Metal)

In other areas, doubler plates were applied and cold bonded using Belzona 1511 (Super HT-Metal), in addition to the Belzona SuperWrap II patches. This is a high-temperature epoxy repair compound designed for metal repair and equipment rebuilding, offering excellent corrosion protection. Under immersion, Belzona 1511 (Super HT-Metal) is suitable for applications up to 150°C (302 °F).

Surfaces were thoroughly wetted out, and an additional layer of Belzona 1511 (Super HT-Metal) was applied to the surface of the pipe to fill any pitting and restore the surface back to its the original profile. The doubler plate was then pressed onto the pipe and held in place until the product cured.

The Result

The high temperature epoxy pipework repair was completed successfully, resulting in a durable, long-term solution capable of withstanding the required thermal and chemical service conditions. The repair avoided welding and pipe replacement, minimised downtime, and returned the system to service quickly and safely.

About the Belzona Distributor – Rezitech

Established in 1968, Rezitech is the sole Australian Distributor for Belzona. Rezitech offers a comprehensive range of industrial protective coatings and epoxy metal repair composites to many different industries including: oil and gas, mining, power, water and waste water, pulp and paper, marine, manufacturing, amongst others.

The application images shared in this case study were captured during the repair and demonstrate how high temp epoxy systems can be applied in real-world operating conditions by trained and experienced personnel.

Frequently Asked Questions