The variety of welding procedures and their requisite shielding gases makes welding a complex and intricate process. In this highly specialised field, so critical to many manufacturing processes, it is important to know that you are getting the best advice.
Air Products’ Welding Specialist, Sean Young, is well-placed to offer such advice.
With a broad knowledge of welding gases and their applicability to specific welding procedures, Young spends much of his time advising customers on how their choice of gas mix can have a profound impact not only on the weld quality, but on long-term cost-effectiveness.
“Sometimes it can take a bit of convincing that the cheapest option is not always the most cost-effective. But for a customer who is looking to make sensible long-term decisions, choosing the best gas mix for a specific procedure can save money and increase efficiencies in the long run,” says Young.
“As an active gas, carbon dioxide used to be the gas of choice – and while it can be effective for a faster and deeper weld, because it is quick freezing, it tends to cause spatter. Using a mixture of active and inert gases, such as our Magmix 3 can reduce post-weld activity – leading to a better weld for the long-term.”
Choosing a gas mix depends entirely on the type and thickness of the metal to be welded. Air Products supplies argon for TIG (tungsten inert gas) welding of aluminium, copper, mild steel and stainless steel, and an argon mix for thicker aluminium or copper.
For MAG (metal active gas) welding of mild steel, three-part gas mixes are recommended. Air Products’ most sought-after gas mixes for MAG welding are its premium brands Coogar-Plus, Magmix 3 and Coogar 84/82.
“When it comes to MAG welding of stainless steel, specific gas mixes come into the picture. For example, an argon/carbon dioxide mix is recommended for the welding specifically of 3cr12 stainless steel. Pure carbon dioxide is not recommended as carbon precipitation can cause cracking,” Young explains. For MIG welding of aluminium, argon is recommended, and a mix of argon and helium for thicker aluminium. Flux core welding of stainless steel and mild steel requires a filler material, which in turn determines the specific welding gas mix.
“While Magmix 3 for general purpose and Coogar 84/89 for structural materials are our most popular brands, the choice of welding gas or gas mixes depends on customer requirements, metal properties, and in certain cases, precise specifications. Mechanical construction, pressure vessels, and civil construction such as bridges, and the use of critical components, for example, all require a specific welding procedure, which determines the welding gas type,” says Young.
In today’s current economic climate, the trend for large manufacturing organisations is to consolidate work areas, which makes for more economical gas usage. However, it is sometimes a challenge to forecast gas volumes and to calculate the most cost-effective long-term usage. To this end, Young makes use of a customised welding cost calculator, an Air Products innovation, which assists the customer in making the right choice and to plan ahead.
“At Air Products we are passionate about providing a service which goes far beyond supply of product. We provide a close analysis of specific requirements and match those with recommendations on the correct welding procedure, shielding gases and filler material. And our customers know that we are always available if they have queries on technical issues.”
Air Products South Africa – having long been at the forefront of welding gases and technologies in this country – has invested substantially in welding skills training and development. For example, the company has been closely involved with the South African Institute of Welding (SAIW)’s Young Welder of the Year competition since its inception in 2004.
With service delivery at the core of its operations, Air Products supplies all its customers, with the full spectrum of welding gases throughout South Africa. “From small packaged gas supply mode (cylinder) to CryoEase® and Bulk delivery, Air Products prides itself on high service levels and turnaround. Furthermore, as the market is constantly changing, we ensure that we keep ahead of trends by constantly looking at innovative ways of delivering the most operationally efficient and cost-effective welding solutions,” Young concludes.