HUNTINGDON Fusion Techniques (HFT) has witnessed a significant growth in orders for weld purge systems capable of withstanding the higher temperatures used during pre-heating of welds. HFT is represented in Australia by Perfect Welding Products .
The purge systems are an extension of the standard HFT product line and incorporate a thermally resistant covering on the inflatable sections of over the product.
There has been considerably increasing interest in a high strength steel alloy generally referred to as P91 over the past decade.
This material is of great value to power stations and refineries since it allows for the use of thinner sections of pipe material with concomitant economies and equal strength.
Welding, however, requires the use of preheat if fusion defects are to be avoided.
Such critical weld joints must be purged with Argon gas to prevent oxidation, porosity and potential joint failure under pressure.
This change in material preference has created a demand for Weld Purge Systems capable of handling the higher temperatures prevailing during preheat.
Purge systems are available from HFT covering the range 150mm to 2000mm diameter and can withstand preheat temperatures of typically 300°C for 24 hours or 250°C for 50 hours.