
Bond & Bolt
ALH Systems has developed an innovative and cost effective method to gain access into live, large diameter gas mains, Bond and Bolt.
Conventional access systems require large excavations including underneath the pipe to install chains. The Bond & Bolt saddle only requires the crown of the main to be exposed, thus massively reducing excavation costs and time.
How it Works
The system works by applying an adhesive to the shot blasted main, before seating the saddle in place. Four holes are then drilled & tapped under gas free conditions before bolts are installed and encapsulated with Series 6 resin. In 2015 the Bond & Bolt saddle was successfully used in conjunction with the ALH large diameter bagtubes, on its first live flowstopping job in central London.
Key Features:
- No need for deep excavation working. Bond & Bolt saddle only requires the crown of the main to be exposed.
- Vast excavation and backfill cost savings, with the potential for a decrease in lane rental charges/road closures
- No impact on host main support.
- Potential reduction in 3rd party damage
- Saddles for 24″ – 48″ diameter mains.
- Designed to work with the System 3 valve and flowstopping equipment.
- Centre hole can be plugged using an ALH Non Tap Plug.
Bond & Bolt Drilling Machine
The Bond & Bolt drilling machine features an integral feed cap and bronze body, for a smooth and controlled drilling operation. The system is centralized around a 1.5” ball valve for gas free working, with interchangeable bodies for each step of the procedure. ALH Systems Ltd offer full training to clients with existing equipment and when new equipment is purchased.
ALH Systems has developed an innovative and cost effective method to gain access into live, large diameter gas mains, Bond and Bolt.
Conventional access systems require large excavations including underneath the pipe to install chains. The Bond & Bolt saddle only requires the crown of the main to be exposed, thus massively reducing excavation costs and time.
How it Works
The system works by applying an adhesive to the shot blasted main, before seating the saddle in place. Four holes are then drilled & tapped under gas free conditions before bolts are installed and encapsulated with Series 6 resin. In 2015 the Bond & Bolt saddle was successfully used in conjunction with the ALH large diameter bagtubes, on its first live flowstopping job in central London.
Key Features:
- No need for deep excavation working. Bond & Bolt saddle only requires the crown of the main to be exposed.
- Vast excavation and backfill cost savings, with the potential for a decrease in lane rental charges/road closures
- No impact on host main support.
- Potential reduction in 3rd party damage
- Saddles for 24″ – 48″ diameter mains.
- Designed to work with the System 3 valve and flowstopping equipment.
- Centre hole can be plugged using an ALH Non Tap Plug.

Bond & Bolt Drilling Machine
The Bond & Bolt drilling machine features an integral feed cap and bronze body, for a smooth and controlled drilling operation. The system is centralized around a 1.5” ball valve for gas free working, with interchangeable bodies for each step of the procedure. ALH Systems Ltd offer full training to clients with existing equipment and when new equipment is purchased.
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