Corrosion-resistant alloys such as 13Cr martensitic stainless steel, duplex, and clad materials require a back purge to remove oxygen from the pipe ID. The purge chamber is integral to the machine. The flow of purge gas is controlled from the open end of the pipe. A built-in oxygen analyzer measures the purity of the gas in the purge chamber in real time. Welding starts when the critical oxygen content is achieved in the purge chamber.
The Internal Pneumatic Line-Up and Copper Backup Clamp is built specifically to handle wide variations in pipe diameter, wall thickness, and out-of-roundness found in pipes manufactured to API-5L requirements. Because the copper shoe segments tolerate such wide variances, fewer are needed compared to rigid shoe solutions. The shoes can also be resurfaced three times, giving you more efficient and cost-effective operation.