Star Cement, a Dubai-based premium quality cement and clinker manufacturer, has made a significant turnaround in its machinery downtime and increased output since it switched from mild steel to Hardox Wear Plate steel grades manufactured by Swedish steel giant SSAB.

The decision has helped decrease downtime by nearly 45 per cent. In addition, the durability of the Hardox Wear Plates has been a key factor that has helped increase daily production by more than 20 per cent, Ozgur Yalcin, area sales manager of SSAB Middle East, tells Gulf Construction.

According to studies, the cement sector is likely to see a continued increase in production costs and cost reduction is likely to remain a focus area over the next few fiscals, during which price pressures are expected to prevail vis-à-vis higher production costs, he says.

“The optimisation of equipment-related costs remains an important factor in improving profitability in the sector. Secondly, ongoing maintenance overheads make for about 15 per cent of the running cost of cement manufacturing,” Yalcin points out.

The constant risk of wear and tear of machinery caused by abrasion can be mitigated by the quality of the steel used for plant equipment. Another alternative to achieve longer lifespans and limit maintenance shutdowns is to use cladded sheets and overlay plates. This, however, is a significantly expensive option, he says.

In a bid to find a suitable solution to ensure equipment longevity, Star Cement invested in Hardox Wear Plate technology. With their unparalleled combination of hardness and toughness, these plates set the standard for abrasion-resistant (AR) steel worldwide. And thanks to their unique qualities, they can even perform as a load-bearing part in many applications, opening new possibilities for structural design innovation, Yalcin says.

Star Cement has a very high production target for its facilities – running for 330 days in a year. The mild steel used earlier had a very short lifespan requiring replacements within six to seven months due to the stresses involved in the industrial processes. In the last four to five years since it switched to Hardox Wear Plate products, the company has consistently been able to meet this target of 330 days of production each year, because of much lower wear and tear.

Velayuthan, the assistant vice-president of Star Cement, credits the company’s increased production performance partly to Hardox Wear Plate technology. “We have been able to increase our capacity from 6,800 to 8,300 tonnes per day, without any major modification. We have been able to push our machines to greater extremes because of the performance specifications that SSAB’s Hardox Wear Plate products can deliver.”

Yalcin says Hardox products are also easy to work with. They can be cut with the aid of a standard gas cutting machine, while cladded plates require water jet or plasma cutting. Also, most Hardox varieties – with the exception of Hardox Xtreme – can be welded using conventional electrodes. This allows for quick ongoing maintenance that further extends the gap between scheduled shutdowns.

Furthermore, the wide range of Hardox varieties and grades allow Star Cement the flexibility to mix and match from performance and cost profiles, in order to best address a specific need and a particular instance. For example, Hardox 600 can deliver superior performance to Hardox 400/450/500, for some applications, but not at the same cost advantages.

Star Cement started with Hardox 400 and gradually adopted Hardox 600 as well.

The continuous usage of the Hardox range has helped the company understand the correct application of each type of plate. For example, Yalcin says, some applications might use 450 or 500 but in other areas, where there is higher wear and tear, Hardox 600 could be used.

Choices are often dictated by availability and timeframes as well. Materials such as Ni-Hard steel – an alloy of white cast iron, nickel and chromium that delivers superior resistance to abrasion at high velocities – has to be sourced from India, and is a time-consuming procurement process for Star Cement. Hardox 600, being locally available with a highly effective product range, is a clear choice for the company.

The consistency in quality and performance specifications for Hardox products (within a 10 per cent discrepancy range) is another factor in their favour. Cladded steels are often unable to match such dependable consistency, Yalcin says.

Star Cement most commonly uses Hardox products at the transfer points in its facility, such as chutes and ducts. The product is also used for specific applications, such as in the vertical mill, where the body wear liner in the mill feed chute uses Hardox Wear Plates. Machined Hardox Plates are also used in several pre-fabricated parts supplied to the company by OEMs (original equipment manufacturers).

Star Cement is also highly appreciative of SSAB’s after-sales service and hands-on involvement with customer needs.

Velayuthan says: “SSAB is extremely innovative and makes constant upgrades to its products and range every year. It conducts technical seminars for us, once a year, showcasing their latest developments and products, for which we are offered free trials. We are keenly looking forward to Hardox pipes, which SSAB will be launching soon.”

Star Cement is likely to include SSAB products in the clinkerisation process in the future, says Velayuthan.

Explaining the process, he says: “The post-clinkerisation process operates at 200 to 250 deg C - a relatively higher temperature than other stages of the cement manufacturing process. Also, the equipment used in the clinkerisation stage at the Star Cement facility runs continuously for 250 to 300 days. The company is investigating SSAB’s Toolox range of prehardened and tempered tool steel – designed for dimensional stability, high impact tolerance and low residual stresses – in order to enhance the efficiencies of these processes at its facility.”

The company will be trying out SSAB’s Toolox and Hardox high temperature plates for applications in clinkerisation during its next shutdown.

Star Cement has emerged as a major premium cement manufacturer in the Gulf and Indian Ocean Rim. It has manufacturing units in the UAE, Bahrain and Bangladesh, and trading hubs in the Middle East, African and Asian markets.