One of the world’s leading producers of on-site nitrogen generation technology, domnick hunter, is practising what it preaches by using its own MAXIGAS equipment to replace storage cylinders for welding gases in its own production of stainless steel vessels.
domnick hunter fabrication installed an N2MAX116 nitrogen generator to reduce its reliance on argon for welding of stainless steel vessels the company sells around the world, including Australasia, for high purity gas a liquid purification applications such as food, beverage or pharmaceutical production.
Annual expenditure on gas has since been reduced by around 66 per cent, while quality of stainless steel products imported to Australasia and world markets has been enhanced, says domnick hunter Australia Business Development Manager Mr John Davis.
More than 5,000 stainless steel vessels are produced each year at domnick hunter’s Boldon Business Park site in the UK, for export to domnick hunter customers for whom cleanliness and sterility are paramount and finish quality is a very important consideration. Such customers in Australia range from wine and snackfood producers to chemical companies.
This system typically protects the molten weld pool at 3 points:
1) At the weld torch
2) Trailing the weld
3) The backing or root of the weld, where a purging or backing gas is used.
In addition to its relatively high cost, cryogenic argon can be very temperamental following any kind of shutdown, such as holidays, or during ambient air temperature changes in summer months, when it can off-gas to the atmosphere and cause to expensive losses.
domnick hunter’s MAXIGAS generator delivers nitrogen gas from compressed air with a purity of 99.999% at a flowrate of 7.3m3/hr. It replaces traditional cylinders used to store gas, eliminating OH and S handling issues with the cylinders, the cost of the cylinders and interruptions to production caused as cylinders are changed.
dh fabrication still maintains a small argon cylinder supply for weld gas, but nitrogen is now used for the purging and trailing gas.