WITH specifications and regulations set to become more stringent in the region with regard to the installation of roofing membranes, BMC Gulf is relaunching Bitumat B2, Leister’s innovative tool that makes flameless welding possible.

The tool uses hot air instead of an open flame to seal elastomer bitumen membranes that are commonly used as a roof sealing system for flat roofs.

A bitumen seal is associated with certain dangers as many contractors are still using an open flame for welding it, says Richard Honein, technical consultant at BMC Gulf, Leister’s exclusive sales and service partner for the Middle East. In the installation process, sheets laid out are subject to large-scale flame treatment with a Bunsen burner and the overlapping sheets are then pressed and fused onto the lower sheet.

“This is a method fraught with risk, as the thermal insulation located below the seal or the flammable roof substructure can catch fire. As a result, more and more building owners are prohibiting the use of an open flame for safety reasons, in particular in the oil and gas industry where the use of  an open flame is banned,” he says.

While bitumen continues to be the popular sealing material for roofs, there is increasing pressure to avoid open flame during the roofing work. With Bitumat B2, Leister offers a welding tool that provides a solution by welding the bitumen sheeting with hot air.

“Proactive companies working with bitumen are committing themselves to working without an open flame in new projects, and those that have already been working with hand-held tools from Leister are firm advocates of the quality provided by these tools,” says Honein.

Although the world’s top-selling hand tool Triac S and the more powerful Electron have been used for detailed welding work in the Middle East for as long as anyone can remember, work on bitumen roofs is still carried out with an open flame for large-area welding, he points outs.

“With building owners now requiring installation companies to abandon this practice, it is now clear that a proven solution has to be used for welding the base seams: with Bitumat B2, Leister provides a hot-air welding machine that meets all requirements,” he adds.

This apart, Leister also meets the requirements of professional roofing contractors that expect the best in terms of quality by providing a perfect tool backed by a well-trained workforce. The long-established Swiss company not only has suitable tools but, with its international network of more than 120 certified sales and service centres, it can also ensure that clients are able to use these tools perfectly, Honein adds.

In the Gulf region, BMC Gulf organises intensive training for customers with regard to Bitumat B2 and other Leister welding machines. “In the past, BMC has shown that work with the new hot-air machine not only offers an alternative to an open flame but represents the ideal solution in every respect. The high-performance nozzle specially developed for working with bitumen enables a working speed of up to 7 m per min, depending on the material,” says Honein.

“In addition, while welding with an open flame requires two workers on the job – one for heating and the other for pressing on the bitumen sheeting – Bitumat B2 requires only person to operate it. A high working speed and low personnel requirement together mean excellent economic efficiency,” he adds.

Bitumat B2 has an integral air separation. This is a rotating rubber belt located between the drive and pressure roller, which ensures that the bitumen sheet at the top is pressed downwards during the welding process, while the controllable hot-air volume is routed precisely between the bitumen sheets. This results in homogenous, uniform and neatly welded seams. The air insulation also prevents shrinkage of the thermal insulation located below the bitumen sheeting.

“In controlled peel tests, Bitumat B2 achieved significantly better results in comparison to an open flame method for all materials compared. Applicators benefit from better and safer work conditions: the height-adjustable and swiveling guide bar of Bitumat B2 makes control simpler and easier during the welding process. Besides the adjustable parameters for speed, temperature and air volume, the press-on force can also be increased to suit the material by attaching an additional weight,” says Honein.

He adds that while bitumen remains attractive to building owners, with specifications and regulations for roof membrane installation set to become more stringent in the near future, many companies are forced to meet these regulations, as well as the demands of insurance companies and of building owners and seek out alternatives to welding with an open flame.

“Some have found one such solution with Bitumat B2, ensuring they are well placed for the future. Quite apart from the safety aspect, the improved processing quality, ergonomic way of working and high economic efficiency are convincing arguments in favour of welding with hot air and hence with the Bitumat B2,” Honein concludes.