HFT’s PurgEye 100® bring advances in electronics, ease of use

Huntingdon Fusion Techniques (HFT), the company that introduced the first weld purge monitor in 1975, is offering a new design. Weld Purge Monitor™ is a name chosen to emphasize the device’s specific application; while it is used to indicate when oxygen has been sufficiently removed from a work zone so that welding may begin, it was specifically designed to be a simpler weld-purging device that allows welders to make oxide-free welds without discoloration or coking.

While several revisions to the original design have taken place over almost 40 years, the developer said its new PurgeEye® 100 offers significant advances over other instruments intended for the application of weld purging. The principle consideration was to build a device with electronics that would give accurate readings at the lowest level of oxygen sensor technology, HFT reported.

HFT’s Integrated Auto-Calibration feature displays 20.94% oxygen to start, and then can be calibrated once purging has reached the lowest oxygen level.

For example, oxygen monitors, using the same sensors, indicate that oxygen levels are accurate near ambient levels of 20.94%, for health and safety purposes. Weld Purge Monitors provide accuracy at the opposite end of the scale, to show welders when all of the oxygen is absent.

In addition, because welding operations endure numerous stray electromagnetic signals that interfere with electronic products and the production of stable, correct readings, the new device incorporates the developer’s electromagnetic shielding technology for its welding electronics.
 
Zero calibration — Until the introduction of the PurgeEye® 100, users of Weld Purge Monitors and oxygen monitors have had to make a nominal calibration of their instruments prior to each use by carefully tuning it with a potentiometer knob. Because of the instability of the readings with oxygen measuring instruments of this type, the setting was lengthy and time-consuming.

Now, with the Huntingdon Fusion Techniques’ new ‘Integrated Auto-Calibration’ feature, the 20.94% start level displays instantly at the press of a button. Then, once purging has reached the lowest oxygen level, the button can be pressed once more to calibrate that reading precisely, giving instant calibration at 0.01% O2.

Also, there is no need to return the PurgeEye® 100 device to the supplier for recalibration (as is the case with other oxygen measuring instruments) nor for annual checks once sensors are changed. With the new HFT calibration facility this time-consuming and costly step can be eliminated.

Another new feature of PurgeEye 100® is a tripod mount integrated in the instrument housing. Monitors can now be located securely in an accessible viewing position without having to resort to additional clamping fixtures, and eliminating the risk of instruments falling to the ground, often from great heights.

For operations that have a corporate policy about instrument protection and security, HFT will provide a rubber housing as an additional accessory with the PurgEye 100®.

Easy recognition — The new device has a display field with digits that are 41% larger than on previous models, meaning that operators can recognize them more clearly and from longer distances. As for accuracy, the PurgEye 100® has a software algorithm to correct readings at the low oxygen levels to ensure accuracy and repeatability of readings. HFT noted that most low-cost oxygen monitors are made for measuring oxygen for personal safety, at breathing levels, rather than for welding. As such, they are unable to read accurately as oxygen levels fall below the atmospheric reading of 20.94%

When the battery life is too low to provide sufficient power to run the PurgEye100® properly, the operators receive a visual alarm warning him to change the battery. Similarly, a sensor symbol will appear on the touchscreen to alert the operator to change the oxygen sensor. Once the symbol appears, the operator has time to order a new oxygen sensor without having to stop a job while waiting for delivery for a new sensor.

HFT noted that older instrument designs and other oxygen monitors have complex sensor wiring that involves plugging in wires and clips. The new PurgEye 100® replacement sensor has no wires, but connects easily by plugging it on the brass terminal pins located within the housing.