Purchasing Tungsten Solely On Price

Technical Tip

A well known, publicly traded manufacturer of aerospace components is preparing for a routine NADCAP welding audit. (As far as a NADCAP audit can be routine.) The 2% Thoriated tungsten electrodes they use in manufacturing are sent to an independent testing laboratory to verify that they are within AWS specification. There is a two-month lead time to get the report back and when it does come back, the report states that instead of the expected 1.7% to 2.2% Thoria content, the electrode actually consists of 2.93% Thoria. With only four weeks left until the audit is scheduled to begin, there isn’t time to get another lab report on a different batch of tungsten. The supplier from whom they purchased the tungsten is out of business. The well known, publicly traded manufacturer of aerospace components is faced with the prospect of writing a letter to several hundred customers saying they will no longer be able to perform NADCAP certified welding.

Think that sounds farfetched? Think again. It happened. Fortunately, the company was able to find a new supplier who could get independent lab reports on new batches of tungsten rushed through in ten days.

But what happened next was even more surprising and alarming. The aerospace company had been using Chinese tungsten, purchased on the basis of price. So the new supplier went to their local wholesalers and got three new lot numbers of tungsten, from three different Chinese mills, marketed by three different, nationally known welding supply organizations and had them tested. Astonishingly, although the tungsten packaging clearly stated that the tungsten fully conformed to AWS specifications, in fact, not one of the tested batches met the AWS criteria. Their test reports came in at 2.5% to 3.5% Thoria content, which is not acceptable. The new supplier then had a batch of 2% Th tungsten from Global Tungsten Products (GTP) tested and the test came back: at 2.2% Thoria content it met AWS specifications.

One thing that bears pointing out is that most tungsten suppliers will provide, on request, chemical certifications of the material they have shipped, leading the distributor to believe the material is in spec. But read those chemical certifications carefully. Are they written in a generic form? Do they state the lot heat number and the date of manufacture? In most cases, if the tungsten is from China, the answer to the first question is yes and the answer to the second question is no.

Now, chemists and engineers can argue amongst themselves as to whether having 3.5% Th content instead of 1.7 – 2.2% matters to the quality of the weld. But the point here is that a specification for the weld is written for a reason and if some part of that specification is not met, doubt is cast over the integrity of the entire welding process.

Yes, the Chinese tungsten sold for $12.00 and yes, the GTP tungsten sold for $24.00. Was it worth it to put a 100-million-dollar-a-year piece of business on the line over an annual cost difference of less than $1,000? As a percentage of the value of the products that are being created, the cost of the tungsten electrode is so low, in a great many cases, it can scarcely be measured. And yet, in today’s market, company after company make the tungsten purchasing decision based solely on price.

There is enormous, potential liability for both the user and the supplier. For the user, it results from using out-of-spec tungsten in critical applications. For the supplier, problems can arise by supplying out-of-spec material that is improperly labeled as being within AWS specifications. End-users and their suppliers all the way through the supply chain need to be aware of the final destination of the tungsten and know how it is going to be used. Does it make any sense that the company producing critical components is using the same tungsten as the bicycle shop down the road? In fact, if the bicycle shop down the road is anything like the bike shops in my neighborhood in Chicago, the completely tattooed and fully pierced welder in the back is probably demanding the finest tungsten available for the masterpiece of weight and balance she is creating, and she will not settle for less. Why then is the industrial producer of critical components down the road purchasing its tungsten solely on the basis of price?

As suppliers, we should exercise some healthy skepticism about the label on that box that says it meets AWS specifications.

Bob Hall

Robert J. Hall is president of Elderfield & Hall/Pro-Fusion, located in Chicago, Illinois, and at www.pro-fusiononline.com.