Strain measurements play key role when Bromma develops new lifting beam for containers

Bromma Conquip turned to HBK Nordic Project Engineering for mounting strain gauges and cables in the right way on spreaders in the field – to achieve a reliable measurement chain.

Assisted by HBK, Bromma Conquip could verify its calculations for the new generation beam, which is now in production. The measurements have been the basis for fatigue calculations for predicting new product life spans. Because Bromma Conquip could follow the ways in which loads perform and how tension varies in real operation, the company now better understands dynamic factors that affect use of its lifting beams. As part of the process, Bromma Conquip has learned other ways to leverage measurement technology in future product development.

For over 50 years Bromma has delivered spreaders to more than 500 terminals in over 90 countries at 6 continents. All in all, more than 20,000 crane spreaders and rotators have been put into service. In addition to that,  more than 10,000 of these are still in operation today. Bromma manufactures up to 2,000 all types of spreaders per a year. In fact, anywhere you go,  you’re likely to see a Bromma spreader in action. We are proud to be a pioneer in technological development. As a matter of fact, Bromma has introduced many firsts to crane manufacturer industry: the first telescopic spreader, the first twin-twenty spreader, the first 45 foot spreader and the first all-electric spreader line. That’s why when you choose Bromma you choose cutting edge technology.

Bromma Conquip already used HBK’s equipment in its own test center in Malaysia. This time, the company wanted to implement the same technology for measurements in the field – at its factory site in Sweden and at customers’ sites in ports in Canada and China.

”Using our staff, we can measure in our test center,” says Idoff, “But when it comes to field measurements, we needed to bring in specialists.”

Sensitive technology

The Bromma Conquip-HBK partnership worked well. HBK set up the measurement chain and took the measurements. Bromma’s development engineers analyzed the results.

“The technology is very sensitive,” says Herman Lingefelt, HBK project engineer who participated in the three projects at Bromma. “So it’s important that everything works perfectly all the time. The process of gluing the strain gauges to the steel construction is critical for reliable results.”

The projects used CX22B-W – small compact data loggers – in combination with the QuantumX MX1615 amplifier and about 60 sensors in a distributed system, which reduces need for cabling.

Cabling a challenge

Cabling still proved to be a challenge, because the beams move in and out when in operation to fit varying container sizes. So cables must be able to move along. Another challenge was that the test had to be run independently for three days – outdoors and in real production – at Bromma Conquip’s customer sites.

“It required some flexibility, but our customers were very accommodating, and our dialogue with HBK flowed very well,” says Idoff. “When problems came up, we solved them along the way, and we learned a lot in the process. Going forward, we now know a lot more about how we can use measurement technology.”

Better dynamic control

Video recording supplemented traditional data collection – a methodology that has become more common in recent years, according to HBK. Consequently, Bromma gets a visual image of what is going on when discrepancies occur in the data. Measurement results matched theoretic calculations, and the new beam is now in production at Bromma Conquip.

“Besides verifying that we based our decisions on the right calculations, we acquired new data that are related to dynamic factors,” says Idoff. “Now we have a better idea of how stress varies in the beam in operation and how the loads behave in real life.”