P.B.S. Purge Bag System
The B&B Purge Bag Systems is the most common inflatable purge bag method in use. This simple and proven design requires little training and immediate results are achieved. For smaller pipe diameters purge times are usually within 2-10 minutes all while achieving shiny oxide free welds. It is not uncommon to pay for the purge bag in as little as 3 or 4 uses in time savings alone. We find this particular pipe purging system performs exceptionally from 2-10 & we offer the P.B.S. for up to 48" pipe.
How it Works: Create a seal, fill the chamber with inert gas, monitor oxygen content drop, weld.
From 2-48 inch pipe diameters
Link to instruction PDF
Features & Advantages
- B&B’s Inflatable Pipe Purging Systems dramatically reduce purging times leading to significant savings in labor costs. Typical purge times for 4” pipe = 1½ mins; 8” pipe = 4 mins; 12” pipe = 8 mins
- Ready to use, connects to a dedicated and regulated gas supply. Choose any flow rate up to 20l a min. Through the preset purge valve.
- Gas pressure control ensures an even positive root bead with no notching.
- Heat resistant up to 158º/70ºc continuously. Higher temp available. See below left.
- Use less inert gas. The volume of purge gas used is less than 2% of that required for a conventional purge.
- Our lowest cost pipe purging system.
Heat resistant option available.
532F for up to 24 hours and 932F for short periods
The Purge Bag Systems are designed around the principle of using 2 dams to create a seal either side of the weld, just far enough away from the weld not to be effected by heat but close enough to the joint to provide the fastest weld purge time. These dams are connected by an armored spinal tube. Once ready to start purging, the system is inserted into the bore of the pipe using the luminous strip to center the system to the weld gap.
When the gas flow is started, the dams inflate and, upon reaching the pre-set pressure, the valve releases the gas gently into the weld chamber, to purge the inter-pipe without turbulence. The Oxygen is removed from the weld chamber through the integral exhaust tubes in the bags. Used in conjunction with Oxygen Monitors to indicate when the required low level of oxygen has been reached, welding can then commence, with the inert gas enabling the welder to produce an even oxidation free penetration weld bead. Afterwards, the dams are deflated simply by disconnecting the purge gas feed and the system easily withdrawn. The design of these systems means that only one gas connection is required for both dam inflation and weld purging.
Part Numbers & Descriptions
Please Contact B&B for Part Numbers on Hi Temp Versions