Grade 10 chain users may also opt to use the greater strength of the chain by buying a smaller chain for the same job. A Grade 10 chain can lift the same load as a significantly bigger Grade 8 chain. Smaller chain is better than bigger chain because it is easier to handle and less expensive to transport.
But with the increased performance comes an increased price. A length of Grade 10 chain may be 15% or 20% more expensive than its Grade 8 equivalent.
In practice, most buyers are sticking with the cheaper option that has worked well enough for them over the years. Most manufacturers are reluctant to reveal what proportion of their sales are Grade 10, suggesting that take-up remains low, particularly in price-sensitive markets such as the UK, France and southern Europe.
The chain’s price premium is not so great once the fittings are included, argues Oldknow. “On a chain sling you have got the master links, chain connectors, hooks, shorteners, et cetera. Overall on a chain sling there is only and 5% or 6% price differential.”
Manufacturers and their distributors would prefer it if the whole market moved overnight to buy only Grade 10 lifting chain systems, because then they would not have to produce both product lines and carry double inventory.
Pewag of Austria is the only major producer so far to make the move to drop Grade 8 completely and offer only Grade 10. Its Grade 10 brand is called Winner. “I think that was quite a brave move,” says a competitor, admitting that he would like to be able to do the same.
Pewag’s Wolfgang Niederkorn estimates that as much as 25% to 35% of the lifting chain market in western Europe is Grade 10. “Grade 10, we feel, is really starting to take off now, much as Grade 8 did in the 1970s,” says John Brindley, UK distributor of Pewag. Others are not so positive.
Niederkorn says that the one country that Grade 10 has not yet penetrated is France, because buyers prefer the low-price option.
Frederic Cardon, managing director of French Gunnebo distributor J Cardon & Fils, agrees. “A lot of end-users target the lowest price possible without considering quality,” he says. “This is a very price-conscious market compared to the northern Europe mentality where quality is more important,” he believes. Cardon says Grade 10 accounts for about 10% of his sales.
His Belgian counterpart, Tom Put, managing director of Gunnebo distributor SKP, says: “For Belgium, I can say that we are quite successful with Grade 10, but it is thanks to Gunnebo’s GrabiQ concept. So it is not only the Grade 10 but also the new system. If we only had to explain the difference between Grade 8 and 10 it would have been more difficult.”
Michael Gough, managing director of Gunnebo UK, adds: “We market GrabiQ on the basis that it is more than Grade 10. We promote it on its design.” He says that Grade 8 is “by far and away still the most preferred in Britain. People are used to using a Grade 8 system and have been using it for so long.” But Grade 10 is gaining ground, he says.
While other manufacturers seem in no hurry to follow Pewag’s lead and drop their Grade 8 products, there are other ways to reduce their costs and encourage market acceptance.
Parsons, for example, now produces only Grade 10 components that are designed for use with either Grade 8 or Grade 10 chain. It is marketed as the Kuplex 8+10 dual grade system – two chains but one set of fittings.
Parsons only offers Grade 8 chains to its existing customer base. New markets are offered only Grade 10, says sales manager Chris Furnish. For example, Parsons appointed a new wholesaler in Australia last year which stocks only Grade 10 chain and the company is now moving into Iran on the same basis.
The search for a definition
When the European standards programme began in the late 1980s, Grade 8 was considered state of the art in lifting chain. The industry has since moved on.
Fine tolerance chain that is equivalent to Grade 10 has been around for 10 years or more for use in chain hoists, but is less well established for chain slings.
The problem is that there is little consensus about what exactly constitutes Grade 10. There is a standard set down by the USA’s National Association of Chain Manufacturers in 2003. And there is a brand new specification emerging from the German manufacturers to be available later this year. The two are significantly different. But there is neither a European nor an international ISO standard.
Even though Grade 8 chain has been around for 30 years, there is still no ISO standard. Nor does one seem likely to be forthcoming from TC 111 SC1 because of differences between member countries. At a European level, agreement has been reached – EN 818 provides a norm for both Grade 8 and Grade 4 chain. Grade 8, for example, is chain with a mean stress of 800 N/mm2.
In general, Grade 10 means that the chain has a mean stress of 1000 N/mm2, but the way the chain is made varies significantly from one manufacturer to another. Parsons of the UK, for example, tempers its Grade 10 chain at 200° Celsius rather than the 400° Celsius used for Grade 8. The German chains are tempered at 380° Celsius, allowing them to be used in hotter environments that the UK-made chain.
The US Grade 10 specification, produced by the NACM in 2003, specifies the maximum working load limits for different diameters of steels, and sets minimum criteria of steel chemistry.
But this specification does not seem to refer to the inclusion of boron for hardening, a common practice in the USA, Japan and South Africa. According to Derrick Bailes, chief executive of the UK-based Lifting Equipment Engineers Association, chain that includes boron must be tested because it is not as predictable.
US or Japanese-made chains would not pass the new German Grade 10 specification because they have too much boron and not enough of another alloy, nickel, according to Uwe Blichmann, an engineer with the Norddeutsche Metall-Berufsgenossenschaft involved in the specification. The Berufsgenossenschaft (BG) is Germany’s industrial safety organisation.
Blichmann says that that the new German specification defines Grade 10 chain as having a maximum usage temperature of at least 380° C and a mean stress level above 900N/mm2. Note that the chain need not reach the theoretical Grade 10 value of 1,000N/mm2. The specification also sets out minimum values for content of alloying metals. While EN 818 specifies that Grade 8 chain must contain at least two of three common alloys nickel, chromium and molybdenum, Grade 10 must have all three.
In general, the German specification appears to be much more stringent than the US standard, which would appear to leave many of the decisions about tempering, alloys and production up to the producers.
The specification is being finalised by the German chain producers RUD and JD Theile. Thiele and Pewag of Austria have also been involved, but have lately dropped out, Blichmann said. The document will not be a standard, or a norm or a code of practice, but it will set out the requirements that need to be met in order to secure an H stamp from the BG. Before the 1992 Single European Act, all chain on the German market was required to have this stamp. Now, since it is considered a barrier to trade, it is not a legal requirement, although it continues to have the status of a quality mark.
As stringent as the new specification is, it is still not enough for some. One European chain-maker has decided to take the entire process to its logical extreme. Through an exclusive partnership, JD Theile (JDT) has expanded vertically into the steelmaking business. JDT has worked with a steel supplier to perfect a formulation of its Enorm Grade 10 chain. “This steel is patented and cannot be purchased by any other company,” says JDT’s export sales manager, Helmut Berndt.
