PurgEye API1000 Remote PHO (photo: Huntingdon Fusion Techniques HFT®)

When welding lengths of tube and pipework fabrications, as well as sections of pipelines of 20 metres length and more, one problem operators face is not receiving a fast and true weld purge reading from the purge zone.

Now, for the first time, Huntingdon Fusion Techniques HFT® makes it possible to have an immediate reading of the weld purge gas at the underside of the joint, from any distance up to 1,000 metres away with their PurgEye® 1000 Weld Purge Monitor®.

Luke Keane, Distributor Support for HFT® says, “By using a remote sensing head, which can be fitted onto any Mechanical or Inflatable Tube and Pipe Weld Purging System from 25 mm diameter upwards, the oxygen level can be measured directly at the weld location and the information will be electronically transferred to the monitor up to 1 km away. 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 is one of our five Weld Purge Monitors® to now feature PurgeNet™, a networking device designed for communicating the current oxygen reading from the Monitor, to another piece of equipment, such as the visual warning accessory PurgeAlarm™ or a Dew Point Monitor with additional inter-pass temperature monitoring.”

If exhaust gas from a normal weld purge system is piped down a hose to a distant measuring instrument, it may take many minutes, or even hours in some cases, for a stable reading to reach the sensor. 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 leading to other problems.

The PurgEye® 1000 Weld Purge Monitor® has been designed and developed specifically to prevent oxidation under distance monitoring conditions and has a sensor placed immediately next to the weld purge site.

The sensor is secured in a tiny module, which is mounted inside the purging system and is connected to the measuring instrument by a data cable. The purge reading is sent back to the instrument at the speed of light, so operators and quality control personnel know immediately when the purge is satisfactory.

This way, the operator can be certain that the weld purge reading is correct and that the joint will not be adversely affected by oxidation, allowing welders to achieve that sought after zero colour weld.

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.

Tags: Huntingdon Fusion Techniques HFT®