Tag: SylPad

Case Study Details

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The stainless steel water cooling system at the oil refinery was meant to have a lifespan of up to 50 years, yet numerous welded joints across the site were already starting to fail after less than half that time.

Microbially induced corrosion was found to be the cause, a type of corrosion relatively little is known about compared to other forms. It occurs when microbes fix to a surface, producing a biofilm layer where multiple bacteria combine to accelerate the corrosive process.

This biofilm affects the electrochemical environment in multiple ways, including changing ion concentrations, pH values, oxidation levels and creating hydrogen sulphide.

As more biofilm layers form, the bacteria and microbes are given greater protection from treatment methods such as biocides, chemicals and temperature treatments. It becomes increasingly difficult to slow corrosion or eliminate microbes from the pipe system.

Stainless steel normally has enhanced protection against corrosion thanks to its passivation layer, which prohibits microbes attaching and makes a surface less prone to developing biofilms. But if the passivation layer is damaged, microbially induced corrosion will take place.

Installation of the water cooling system at the oil refinery included welding joints together. Unbeknown to the refinery, this had weakened the internal passivation layer of the stainless steel pipework.

When the water cooling system went live, microbes in the water were able to settle on the uneven surface at each welded joint. Bacteria collected and a corrosive action began between the metal and the microbes, attacking the stainless steel from the inside.

Eventually, a series of leaks appeared at welded joints throughout the water cooling system. This represented a major problem at a relatively new and expensively built facility. Replacing the stainless steel pipework was not an option due to the cost and disruption it would cause.

With every welded pipe joint now a potential point of failure, the oil refinery contacted Sylmasta to find a repair solution. Sylmasta recommended the refinery stock a range of different sized Wrap & Seal Pipe Burst Tape and SylWrap HD Pipe Repair Bandages, which permanently seal live leaks when used in conjunction.

Online pipe repair capability was essential to the oil refinery as draining the system would result in at least five days loss of production, along with vast costs for diversion of water.

Over 500 SylWrap HD Bandages and 1,700 Wrap & Seal Tapes were sent to the refinery. Sylmasta also flew to the Middle East and spent a week training, testing and certifying refinery installers and supervisors on using the products.

Workers were shown how to apply Wrap & Seal for high-pressure live leak repair. Wrap & Seal stretches by three times its length and amalgamates together, fusing to form a solid rubber band containing pipe content.

Multiple Wrap & Seal Tapes applied on top of each other amalgamate in the same way, building pressure resistance up to 30 bar. This was more than suitable for the cooling system, operating at a maximum 10 bar pressure.

For pipework 150mm diameter or above, workers were also trained in using SylPad Pressure Resistance Multiplier. SylPad is applied alongside Wrap & Seal when making live leak repairs to pipes 150mm diameter and above.

It better concentrates the pressure resistance of Wrap & Seal directly over the leak by directing more of the Tape’s elastic force downwards. Depending on pipe size, nature of the leak and repair quality, SylPad can increase the pressure resistance of Wrap & Seal by up to three times.

The final stage of repair involves overwrapping with SylWrap Bandage. SylWrap is a composite repair wrap with a water-activated resin which sets rock hard in minutes. It provides an impact resistant protective sleeve, reinforcing the repair.

Since Sylmasta visited, the refinery have used their extensive supply of SylWrap products to repair numerous leaks in the water cooling system – including to sections of overhead and difficult-to-access pipework where the system passes through constrained spaces.

With eliminating microbially induced corrosion from the system impossible, instant live leak repair has proven the best solution for the refinery.