Process vessels play a vital role in a variety of industries, particularly within the oil & gas and petrochemical sectors. These vessels often contain high-temperature media within highly corrosive environments. Such challenging conditions lead to issues such as erosion, corrosion and chemical attack, which are exacerbated further by elevated temperatures and entrained solids.
However, traditional repair methods can be both time-consuming and costly, often necessitating dangerous hot work. Belzona’s cold-applied solutions simplify maintenance procedures and extend the life of valuable assets.
This blog post offers step one of a two-step guide for the protection of high-temperature vessels. First, mending pitting damage using Belzona 1511 (Super HT-Metal) and then part two, applying an overcoat of Belzona 1593 to ensure lasting protection against corrosion and chemicals.
Part 1 – Repairing Pitting Damage on Process Vessels with Belzona 1511 (Super HT-Metal)
Why Should Belzona Be Used to Pit-Fill High-Temperature Process Vessels?
Before a vessel can be lined, it is crucial to carry out a pitting repair with a paste-grade epoxy material. Belzona 1511 (Super HT-Metal) is an ideal choice as it is a heat-resistant epoxy paste, specifically designed to repair and rebuild areas damaged by corrosion or erosion at elevated temperatures. It can withstand immersed service environments up to 150°C (302°F) and is dry heat resistant up to 210°C (410°F). Its excellent chemical resistance and durability make it well-suited to lining high-temperature process vessels.
How to Pit Fill High-Temperature Process Vessels with Belzona 1511 (Super HT-Metal)
Step 1: Surface Preparation
To ensure a successful pit-filling application, proper substrate preparation is essential. First, the surface must be grit blasted to Swedish Standard Sa2½ (near white metal finish) with a minimum profile of 3 mils (75 microns). It is also vital to ensure the soluble salt contamination levels are below 20mg/m2 (2ug/cm2). Throughout the preparation and application process, environmental conditions should also adhere to those laid out in the Instructions for Use (IFU). This preparation ensures the Belzona 1511 (Super HT-Metal) will adhere strongly to the vessel’s surface.
Step 2: Mixing the Product
Next, measure out Belzona 1511 (Super HT-Metal) at a metric ratio of five parts base to one part solidifier. Mix the two parts thoroughly, using a figure of eight motion, to achieve a uniform streak-free grey colour.
Step 3: Apply the First Coat
Once mixed, carefully use a brush to wet out the substrate with an initial layer, pressing hard into crevices as this helps to prevent air entrapment. Then move on to rebuilding with more product, using a Belzona applicator to restore the surface to its original profile. Ensure the product is spread evenly and covers the entire damaged area.
Step 4: Leave to Cure
Finally, allow the Belzona 1511 (Super HT-Metal) enough time to cure, forming a strong durable repair. Please note the length of time taken to cure varies depending on application temperature so be sure to consult the IFU for specific timings.
Watch This Video to See the Application in its Entirety:
Content Creator, Belzona Inc., Harrogate, UK.
Responsible for writing a range of content including blog posts, press releases and a range of marketing material.