Hot tapping is a technique for forming a new branch or connection to an existing pipework system without draining it down or interrupting flow. Where welding is not possible due to the pipe material, under pressure drilling achieves the same result using a mechanical clamp or branch tee. Together, these techniques allow new connections to be made while the system remains fully live, at full flow, temperature and pressure.
Used where welding is possible. A new branch or connection is welded onto the live pipe, then drilled through to create the connection. Suitable for steel and other weldable pipework.
Used where welding is not possible, including cast iron, ductile iron, copper, plastic and asbestos cement pipework. A mechanical clamp or branch tee is fitted, then drilled through.
No shutdown required — new connections made at full flow, temperature and system pressure
No need to depressurise the line
No loss of inhibitors, anti-corrosives, biocides or water treatment
No venting of air, avoiding further corrosion risk
Assists in Legionella control
Reduces cost compared with full system drain-down and restart
Rapid response capability for emergency situations
Heating systems
Hot and cold water services
District heating schemes
Chilled water systems
Condenser water lines
Fire sprinkler systems
Adding inspection, pressure relief or monitoring points to legacy systems
All work is carried out using pneumatic machines, allowing quick and cost-effective results. For example, work on a 6" (150mm) pipe can be completed in as little as 20 minutes, compared to around two hours with traditional methods.
Bishop Pipe Freezing can conduct hot tapping on pipework up to 12" (305mm) in diameter.
We write to thank you for the company’s commitment to complete the works successfully. We found your involvement, from the very first contact through to completion, invaluable.Trevor Bacon
Tell us what you are dealing with, and we will advise on the best approach.