It is not always practical when welding long tube lines or pipeline sections to measure the oxygen content in the purge gas close to the weld. Many welders face the challenge of the purge gas in the welding zone being contaminated when taking readings from a distance, leading to the risk of a failed weld that needs to be cut out and remade.
To overcome this problem, the PurgEye® 1000 is now available from Huntingdon Fusion Techniques HFT® that will display the oxygen level in the welding zone on a Weld Purge Monitor® screen that might be 10, 50 or even 1,000 metres away from the weld.
The PurgEye® 1000 comprises a sensing head that can be fitted onto any pipe weld purging system that transmits the oxygen level at the weld location electronically to a monitor, up to 1 km away.
Ron Sewell, Chairman for HFT® said: “The PurgEye® 1000’s sensing head can be fitted onto any Mechanical or Inflatable Tube and Pipe Weld Purging System from 1” (25 mm) diameter upwards. Therefore the oxygen level can be measured directly at the weld location. With this capability, the operator can be certain that the weld purge reading is correct and that the joint will not be adversely affected by oxidation.”
The PurgEye® 1000 measures oxygen levels from 1,000 parts per million (ppm), right down to 1 ppm (accurate to 10 ppm), ideal for welding metals such as stainless steels, duplex steels, titanium and zirconium where oxide free, zero colour welds are required time after time.
Without this instrument, weld purge exhaust gas would be piped down a hose to a distant measuring instrument taking many minutes, or even hours to reach a stable reading. The exhaust gas may even be contaminated on the way, by outgassing from the walls of the hose material or from air drawn in through a leaky connection.
In the event the oxygen level is too high, the weld would become oxidised at best and might even have nitrogen and hydrogen absorbed into the joint at worst, which could cause metallurgical defects.