Total supplier of connection technology responds to current events

With over 100 employees, a laboratory and an enormous stock of more than 7,000 tons, Stafa is one of the larger distributors of fasteners in the Netherlands. With a lot of ready knowledge of, among other things, steel construction, the company from Maarheeze always responds to current events. For example, the HV prestressing bolts according to EN 14399 are extremely suitable for constructions that are dynamically loaded as well as for constructions that experience problems due to loosening of bolted connections, currently a hot item.

In steel construction, assembly according to "tensile setting" is common. However, braces and canopies in steel structures may be subject to load reversal, or alternating tensile and compressive loads. In practice, bolt-nut combinations may loosen due to the effect of load reversal. The quality and control of this is becoming increasingly critical. And rightly so, thinks Dick Koopmans of Stafa. "There are more and more questions regarding solutions to the fact that bolt-nut combinations come loose, especially in non-dynamically loaded structures. A good example is the 2017 lawsuit concerning the Gelredo stadium regarding the loosening of bolt-nut combinations. Curiously, this is not always taken into account in design and construction. Often the argument is that cost plays a role, but the cost of annual inspection and subsequent necessary tightening of bolt-nut combinations is not included." Koopmans is referring to the court rulings that made this insightful at the time. "This calls for higher-quality joining techniques, such as HV preload bolts. In Germany, these bolts are already used as standard in the construction of an industrial building, while here in our country, 'pull set' is still common." Stafa has a complete range of HV bolts conforming to EN 14399 at competitive prices and of course a large range of EN 15048 for standard applications.

Stafa has a large package of fastener products aimed at steel construction. "We also have a lot of in-house knowledge of joining techniques," says Koopmans, who himself has been working as a technical sales manager at the family company for more than 21 years. For a year now, Pieter Boermans has been strengthening Stafa's technical sales team, a well-known name with more than 20 years of experience in steel construction. The team is only too happy to point out to steel builders the importance of a good quality connection. "We feel very strongly about quality and are aware of this every day," says Boermans. "We are TÜV certified for both static (SB bolts according to EN 15048) and dynamic HV preload bolts (EN 14399) and even have our own laboratory where we perform tensile tests, Charpy tests, hardness measurements and salt spray tests on our product range, among other things. We can also use our Keyence optical measuring equipment to zoom in on the dimensions of our incoming products down to the smallest detail."

Furthermore, Stafa regularly works on "specials" for specific projects, whether or not coated to suit demand and application. "There is increasing demand for a coating that is better than a standard galvanized solution. Think of constructive connections in locks, windmills, solar parks or swimming pools. Each of these applications has specific characteristics," says Koopmans. "We are well versed in this and can also package it according to the customer's wishes. In our production department, among other things, we can realize threaded rods to customer specifications. In addition, we will soon have threaded rods at lengths under 1 meter in stock as standard. Of course, in galvanized and hot-dip galvanized we stock a large package of hook anchors, threaded rods, hex nuts, lock nuts, turnbuckles and all kinds of variations of bolts."

As one of the largest distributors of fasteners in the Netherlands, Stafa has a broad scope. Nevertheless, the family business is strongly committed to reshoring. "We no longer source all products from Asia by a long shot, because for some time now we have had an exclusive partnership with a European manufacturer," says Koopmans. "That allows us to be even more responsive. Our customers also increasingly appreciate products coming from the EU, for a variety of reasons." Stafa is also known for its extensive packaging capabilities. "Packaging per project, per section, per floor, per part, even in bags ... it's all possible," says Boermans. "We work with a modern software system and can thus support our customers administratively. Think of exchanging information via EDI or XML files. Thus, as a total supplier in joining technology, we try to relieve our customers in all areas. Steel constructors can turn to a single address for all the connections involved in a project. With excellent service, expertise and a competitive price level."