Hot tapping on water mains at Hallamshire Hospital
Client: Hallamshire Hospital, Sheffield
Project overview:
Hallamshire Hospital, in Sheffield, South Yorkshire required the installation of a new 50mm branch connection from an existing 100mm copper mains water pipe, allowing the hospital to convert from a tank-fed system to a direct mains water supply.
Due to the hospital’s reliance on continuous water supply, the system could not be isolated, drained, or interrupted at any point. As one of the UK's leading hot tapping specialists, we were contracted to perform the modification while avoiding any shutdowns.
The challenge:
As hospitals depend on uninterrupted water systems, traditional pipework shutdowns would have caused delays, increased costs, and unacceptable risk. Therefore this intervention required numerous competencies:
Live tapping on potable mains water
Installation of a 50mm branch on a 100mm copper pipe
Zero shutdown permitted due to hospital dependency
Any isolation posed potential health and operational risks
Full compliance with UK potable water regulations required
Our solutions:
A WRAS-approved cold tapping clamp was selected to suit the existing 100mm copper mains water pipe, ensuring full compliance with UK potable water standards. All under-pressure drilling equipment was chlorinated and sanitised prior to installation.
Custom pipe preparation: Acquire a suitable cold tapping clamp to fit the profile of the 100mm copper pipe
Surface preparation: The 100mm main was cleaned to provide a contamination-free surface.
Ultrasonic thickness testing: Before any welding took place, an ultrasonic wall thickness test was carried out to confirm the pipe integrity and ensure it was safe to withstand outside pressure of a clamp.
Pressure testing: The branch fitted onto the live main and subsequently pressure tested to10 bar to verify the integrity of the fittings and the valve.
Under-pressure drilling setup: The under-pressure drilling machine was assembled and fitted with a retaining pilot. This is a critical component, as it prevents the steel coupon from falling into the system and damaging downstream equipment. As experienced hot tapping contractors, we ensure pilots are positioned with absolute precision — too far and it risks penetrating the opposite pipe wall, too short and the coupon will not be safely retained.
Live pipework tapping: The drilling machine was mounted onto the full-bore water valve, and the live pipe tapping operation was successfully completed under pressure.
Approach benefits:
No system shutdown required
Significant time and cost savings
Safe live working under pressure
Fully compliant with UK potable water standards
No hot works
