Air Products offers precision shielding and purging
Air Products offers its professional welding customers a range of more specialised shielding and purging gases. These gases, named Astec, Protec and Hytec, offer those in the professional metal fabrication industry superior welding speed and quality.
“Air Products produces an excellent general-purpose shielding gas called Coogar. However, with these more specialised gas blends, a welder can get significantly higher welding speeds,” explains Air Products’ Manager: Welding and Cutting Gases, Colin West.
Astec gases are formulated to meet stringent requirements mainly in stainless steel and aluminium welding. With Astec, better heat input control improves the mechanical properties of stainless steel, giving superior penetration and sidewall fusion in the joint.
Other gases in the Astec range are Astec 15, 25 and 30. Astec gases are a blend of argon and helium, the blend being intended for the welding of aluminium, copper and stainless steel. Astec 15, for example, gives better droplet formation on thin stainless steels, while Astec S3 is a metal active (MAG) welding gas for austenitic stainless steels.
On the other hand, the argon-hydrogen mix used in Hytec 5 makes for a shielding gas capable of increasing welding speeds by 37%, in comparison to a pure argon blend.
“These gases, although more costly, give improved welding qualities to both ferrous and non-ferrous metals,” says West.
These gases are not limited to welding only, as some can also be used for purging stainless steel tubing. For example, where a pipe is undergoing welding, the pipe is filled with the inert purging gas. This ensures that the weld surface exposed on the pipe interior is protected against atmospheric contamination. Protec ‘backing’ gases, which are a blend of nitrogen and hydrogen, have been specifically designed for purging. In food or pharmaceutical processing, this quality of welding is essential.
However, some professional welding customers, who are concerned about containing costs, may not always see the long-term advantages of a specialised gas. Air Products has technical experts on hand, who are happy to answer any customer queries.
The advances in welding technology have seen an ever-increasing demand for all types of welding gases. Air Products adds value to its customers’ businesses through innovative delivery solutions.
For example, one of these is Air Products’ highly cost effective small liquid-delivery (SLD) technology. This uses large-volume Maxitanks, which can be replenished from a specially designed Air Products’ delivery truck. This system eliminates the need for keeping a multitude of cylinders on site. The use of Maxitanks allows for less handling, with improved safety and housekeeping. Maxitanks give their users superb flexibility, as they can draw off exactly the correct blend of gases from various cylinders by means of a mixing panel.
Air Product’s most popular brand name for welding is Coogar. These range of welding gases have been in existence since the early 1970’s and are the leading brand for MIG/MAG applications.
“The downside is that overwhelming popularity of Coogar has seen customers tending to demand it for all MIG/MAG welding applications, not realizing that there are specialised welding gases which could offer more cost effective welding,” explains West.
To help customers choose exactly the right welding gas, Air Products has developed a database called Gas Selector. Gas Selector makes choosing the right gas as simple as clicking through to a website. Then, completing four straightforward questions brings the name of the recommended gas on screen. The data is formatted to the cylinder identification chart, making selection simple.
“Gas Selector ensures that our customers have access to the best products for their particular welding needs,” concludes West.
For more information, contact:
Colin West – Manager: Welding and Cutting Gases
Air Products South Africa (Pty) Ltd
Tel: +27 11 977 6415
Email: westcw@apsap.co.za
Published on April 21, 2008 in Air Products News, Product News |
Taking the heat out of the kitchen
A lot has been said recently about the impetus of lifestyle change, to the range of fresh and prepared foods offered in South African supermarkets. A new generation of consumers are demanding nutritious meals consisting of either fresh or prepared foods, that can very easily be served at home and require minimal preparation time. These discerning shoppers are prepared to pay a premium to enjoy quality meals and we have seen new packaging technology like Modified Atmosphere Packaging applied to many new products. Air Products’ FreshlineTM gases are now widely used in by growing number of different food processors to produce these attractive high-tech packages.
If we look one step back in the ‘food chain’, we find that food technologists face increasing challenges to ensure that the components of ready meals are presented and packaged attractively and that factors like texture, colour and moisture content are not compromised. This immediately raises questions around the technology best suited to cool, chill or freeze fresh prepared foods and meals, in order to avoid degrading their quality in the process.
Production of these ‘lifestyle’ food products often requires hot liquids like gravies and soups, to be cooled very rapidly in order to retain their full flavour, or for a coating of herbs or sauce to be applied without the food pieces sticking together. Without this capability proportion-able ready-prepared mixed meals are impossible to produce. Again Air Products have developed technology that not only enables this but enhances productivity too.
The term Individually Quick Frozen (IQF) is widely used (and misused), to describe the process required for foods like prawns or raspberries that can be very difficult to freeze satisfactorily, to be frozen singly, while preserving their individual form, texture and taste. Employing the high power of refrigerant liquid nitrogen (LIN) has over many years been proven to be the preferred technology for IQF food production. First introduced in the USA in 1965, Air Products’ CRYO-QUICKtm tunnel freezers were used during the 1980s in SA to freeze foods including burger patties, ice-cream, potato chips and baked foods. At that time low capital cost, quick installation time and the favourable ratio of throughput capacity to required space, made this technology particularly attractive.
The seasonal fluctuations of supply and demand are factors that play havoc in the commercial markets for fresh produce everywhere and in many different markets (CRYO-QUICKtm LIN freezing tunnels) are the automatic choice for adding capacity to freeze meat cuts, burgers, fish fillets, poultry products, seafood, bakery products, ice-cream, appetizers, ethnic foods and ready meals. Liquid Nitrogen freezers are now available from Air Products in several new configurations that have been specifically developed to process a variety of other food products that have properties unsuited to chilling or freezing on the conventional mesh belt, like tomato paste pellets, liquid egg, cream and fruit puree. LIN freezing can be easily integrated into existing production systems whether continuous or batch operated
Freezing with LIN differs from mechanical refrigeration in another way that has recently gained additional significance in SA because the liquid refrigerant is not recycled but instead is delivered cold in cryogenic tankers at a typical temperature of around -195 degrees Celsius. Mechanical refrigeration regardless of the refrigerant used depends on gas compressors that are usually electrically driven, to recycle the refrigerant through the system. Mechanical freezing also consumes significant time in cooling (mainly in houses) compared with LIN Freezing which takes minutes. Not only does this add to the energy demand of any given food production plant, but also raises its’ dependency on a reliable supply of electric power. The luxury of low-cost reliable electric power enjoyed in SA during the past 25 years is gone and not likely to be available here in the foreseeable future.
Liquid Nitrogen Freezing Systems from Air Products, used alone or in conjunction with mechanical systems, provide significant opportunities to the food processor. A PC based evaluation tool has been developed to help analyse some of those benefits. This program provides an indication of the best freezing solution for your needs.
If your current or planned future product range includes any of those mentioned above, why not call Sachin at Air Products (011 977-6430) for a no-obligation evaluation of the benefits that LIN freezing might offer? Additional information and illustrations can be seen by clicking the link below: http://www.airproducts.co.za/food/freezing.htm#
Published on April 8, 2008 in Air Products News, Product News |