Case Study: Leak Repair & Encapsulation of a Steel & Iron Welded Pipe Joint

Good deed done – Sylmasta answer a church’s prayers with a pipe repair and encapsulation miracle

A church central heating system had suffered heavy damage caused by corrosion and begun leaking at a joint where a 100mm cast iron pipe met a 50mm steel pipe via a welded steel plate, leading to a challenging leak repair and encapsulation application.

Case Study Data

United Kingdom
Repair Type
Leak Repair
Leaking welded joint between a 100mm cast iron pipe, a 50mm steel pipe, and a 6mm steel plate

Products Used

Sylmasta AB Original Epoxy Putty
Epoxy putty with two-hour work time allowing for careful application and watertight encapsulation of the leaking joint

Wrap & Seal Pipe Burst Tape
Self-fusing silicone repair tape used initially to seal leaks on the 100mm cast iron pipe

SylWrap HD Pipe Repair Bandage
Applied over Wrap & Seal to provide a rock hard, impact-resistant layer to the initial repair.

Case Study PDF

Case Study Details

Several years previously, the central heating system in the church had undergone renovations when a 100mm cast iron pipe had been stepped down to a 50mm steel pipe.

To facilitate this, a 6mm thick steel plate had been attached to the end of the larger cast iron pipe with a hole cut into the middle, through which the smaller steel pipe was attached and welded.

Since the work had been carried out, the system had become badly corroded and was now leaking from numerous areas around the welded joint.

When a similar problem had developed on another heating pipe, the church had fitted a pipe repair clamp at considerable expense. Such a repair method was not possible on this occasion as the new leak was in a restricted space with no room for a clamp to be applied.

Initially, the church called in welders to try and fix the problem, but this just caused further leakage and left an even more uneven pipe surface needing to be sealed.

Planned repair of a welded joint leaking where a cast iron pipe steps down to a smaller steel pipe via a steel plate
Diagram showing the repair in question

The main leak was between the steel plate and the 100mm cast iron pipe with particularly heavy corrosion at the point where they met. Once the corrosion was filed back, this was relatively straightforward to repair using a SylWrap Universal Pipe Repair Kit.

Wrap & Seal Pipe Burst Tape was applied around the pipe, fusing to form a solid rubber band over the problem area to seal the leak. This was then overwrapped with a SylWrap HD Pipe Repair Bandage, providing a rock hard, impact resistant shell to reinforce the initial repair.

More challenging was the repair of the joint between the smaller 50mm steel pipe and the steel plate. Here, leaking was caused by uneven welding, whilst a threaded section of pipe close by was also suffering from a leak.

It became clear that a softer repair material was needed to smear into the threaded section and to penetrate into the weld. Because of the complexity of the repair, Sylmasta recommended Sylmasta AB Original Epoxy Putty.

AB Original is a smooth-setting epoxy with a two hour cure time. This longer working time allowed for the putty to be more carefully applied, encapsulating the whole section where the 100mm pipe, the 50mm pipe, and the steel plate all met.

The church were supplied with 1kg of Sylmasta AB, more than enough for their application. Unused AB Original stays fresh when left in its original packaging, ensuring the church has a supply of epoxy putty for any future applications.

Sylmasta AB Original putty was smoothed over the welded joint, filling in all imperfections and sealing all leak areas. It has excellent corrosion resistance, further protecting the pipe from future attack, and provided a smooth, ceramic-like finish to the application.

When the church first contacted Sylmasta, they had been looking for a repair method that would temporarily fix the leaking central heating system until funds allowed for either a longer lasting solution or for a new pipe to be installed.

Instead, the repair provided by Sylmasta will be permanent and was made at a fraction of the cost of other options, saving the church a considerable amount of money.

If you have an application you would like to enquire about, then please get in touch

Call: +44 (0)1444 831 459

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