Gulf Construction Online - Leister helps tackle PVC welding challenge

Pipes

Extrusion welding a pipe bend with the Weldplast S2 PVC.

Leister helps tackle PVC welding challenge

01 August 2012

PVC (polyvinyl chloride) extrusion welders from Leister Technologies have been successfully used in the region to tackle the challenge posed by PVC welding, says BMC Gulf Trading and Contracting, the exclusive sales and service partner in the Middle East for the Swiss manufacturer.

Leister’s Weldplast S2 PVC extrusion welders – whose display shows both the temperature in the weld zone and for the pre-heat hot air – are highly suitable for welding PVC pipes, a spokesman for BMC Gulf says.

Elaborating on the benefits of these welders, he says: “PVC is very sensitive to fluctuations in temperature during welding. Improper temperature control can lead to weak weld joints or overheating. That’s why the Weldplast S2 PVC is equipped with an electronic temperature control. Also, no manufacturer can afford to have welding quality issues when producing large containers or large-diameter continuous piping – and this is why professionals choose to use Leister PVC extrusion welders.”

The cover of a huge container is welded with the tool.

These welders have proven themselves in applications in the region, says the spokesman citing an example of a UAE-based company, which has seen an increase in orders on the back of considerable investments made by the government, thanks to the top performance and reliability, and highly economical operability of Leister equipment.

He says the company has recently transformed itself from a simple supplier of corrosion-resistant containers to a complete provider of wastewater treatment plants for the chemical, medical and metal industries.

“PE (polyethylene) and PVC are used in almost all products made by them,” he explains. “Some of the prefabricated products are manufactured using extrusion processing or injection moulding. However, these processes are only suitable for relatively small components and for a limited range of shapes. Given the steadily increasing demand for large containers and pipes with complex forms in the market, extrusion welding is the method of choice to join these parts.”

Prefabricated products in the plant ... ready for welding.

Major projects are often required to be executed in very tight time-frames – which puts those working on material processing under a great deal of pressure. “Prior to using Leister PVC extrusion welders, the UAE company had to weld each seam several times,” the spokesman points out, adding that these machines have simplified the welding process.

He continues: “As a general rule, pipes with a diameter of less than one metre are assembled at the factory. Larger elements are welded directly at the construction site. With the Weldplast S2 PVC, elbow fittings and T-fittings can be welded very easily. The finished welding seam is then polished to achieve a good surface quality. The company also has a Fusion 2 extrusion welder, which it used for welding HDPE (high-density polyethylene) pipes before acquiring the Weldplast S2 PVC. Both extrusion welders enable the relevant welding parameters (temperature and output) to be quickly adjusted according to the material used, resulting in consistent, reproducible welding results.”

HDPE test welding with the Fusion 2 to determine the welding parameters.

The spokesman says the company decided to purchase the Weldplast S2 PVC extrusion welder after seeing it in action at a trade fair. “They were so impressed by the quality of the welding seam and the efficiency of the machine that they ordered two machines the very next day. Shortly afterwards, they sent another order, bringing the total number of these machines it owns at five,” says the BMC spokesman.

“The performance and reliability of the Weldplast S2 PVC deliver a significant competitive advantage for them. The company can now tender competitively for even the most technically demanding projects,” he adds.