Case Study Overview

Site Hospital
Location United Kingdom
Repair Type No pressure pipe repair
Defect Hairline crack in cast iron waste pipe U-bend

Repair Products

CrackSeal Sealant, SylWrap HD Pipe Repair Bandage,
SylWrap Drain & Waste Pipe Repair Kit

Case Study PDF

Case Study Details

Damp patches were noticed in ceiling tiles above a busy corridor in the hospital. A maintenance worker climbed up a ladder, removed the tiles and accessed the roof space above to investigate.

They found a complex network of cast iron pipework. One of these pipes came down through the ceiling, into a U-bend followed by a 90-degree elbow before connecting with two other waste pipes via a Y-joint.

The problem was found to be a hairline crack across the U-bend located directly above the Y-joint. Wastewater was seeping through this crack, corroding the three pipes at the Y-joint where they met below and dripping further down to discolour and damage the ceiling tiles.

To replace the cracked U-bend, every pipe connected to it – including the Y-joint – would have needed to be removed to gain enough access.

The cash-strapped NHS trust responsible for the hospital could not afford the cost of effectively taking the entire system out of operation.

Research by the maintenance team led them to the SylWrap Drain & Waste Pipe Repair Kit, which is already used by several NHS trusts in England for making fast, straightforward and cost-effective repairs to leaking cast iron and plastic pipework on their estates.

All the products in the Drain & Waste Kit are lightweight enough to be applied from the top of a ladder. The repair started by using CrackSeal Pipe Sealant to fill the crack in the U-bend.

Using a standard sealant gun, CrackSeal was extruded directly into the crack. As a moisture curing sealant, it began to harden almost instantly. Within 10 minutes, it had formed a skin to leave the pipe fully sealed.

CrackSeal was then reinforced using SylWrap HD Pipe Repair Bandage. Although the U-bend was a difficult geometry to wrap the bandage around, the worker managed to apply it effectively.

The resin in SylWrap was activated using water and the bandage wrapped and smoothed around the U-bend. Once the U-bend was covered, wrapping continued vertically to cocoon the entire repair area.

SylWrap set rock-hard within minutes of application, providing the entire leak area with an impact-resistant protective sleeve capable of containing any future leaks should the weakened U-bend become breached in future.

The worker completed the cast iron U-bend repair in under 15 minutes. The speed of the repair prevented hospital water damage from a leaking pipe and meant patients and staff saw little disruption, other than the corridor being out of use whilst they were up the ladder.

With the Drain & Waste Pipe Repair Kit containing enough products to seal multiple cracks and holes in different types of pipework, the hospital now have CrackSeal, Superfast Steel Epoxy Putty, SplitFill Epoxy Adhesive and SylWrap HD Bandages on-site in an easy-to-store case for use when future leaks occur.

Products Used

CrackSeal Sealant
Sealant extruded directly into cracks in pipework, where it hardens almost instantly

SylWrap HD Bandage
Composite repair wrap sets rock hard to create reinforced sleeve around pipework

Drain & Waste Pipe Repair Kit
Specialist kit containing enough products for multiple drain, waste and sewer pipe repairs

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