The Southern African Plastic Pipe Manufacturers Association (Sappma) says the quality of plastic pipes manufactured in South Africa leaves room for improvement, despite the fact that many of the pipes carry the South African Bureau of Standards (SABS) mark of approval.

Speaking to Engineering News, Sappma CEO Jan Venter reports that the results of the second round of random sampling undertaken by the association, which sampled pipes from a number of sources, showed that there were a number of discrepancies in the manu- facturing of plastic pipes in South Africa.

“As there is a wide range of pipe standards, we only focus on four standards – SANS 1601, SANS 791, SANS 4427 and SANS 967 – which evaluate pipe stiffness, wall thickness, length and diameter respectively. The tests are conducted by an independent laboratory and huge discrepancies and a significant nonconformance factor was found,” he adds.

“Sappma works very closely with the SABS in a joint effort to weed out inferior- quality plastic piping systems. It is our vision to create absolute quality, trust and integrity throughout the value chain of the Southern African plastic pipes industry,” he notes.

As the plastic piping business is a strategic industry, hardware needs to be reliable for extended periods. Long-term product quality is, therefore, fundamental and high-quality plastic pipe should be good for a minimum of 50 years, according to industry standards.

“However, the plastic pipes industry finds itself in an increasingly difficult position, owing to economic pressure. In a situation such as ours, where supply continually exceeds demand, manufacturers are looking for ways to cut costs, which often impacts negatively on product quality,” Venter explains.

He adds that a toll was taken on the industry during the world financial crisis. “The pipes industry works closely with the civil works industry. Our demand will increase as this sector increases but, at the moment, it is still very slow,” he adds.

To ensure compliance and high standards throughout the industry, Sappma launched a sampling exercise of a selection of pipes obtained at random from various stocking merchants at the beginning of 2011. The dimensions and stiffness of these pipes were tested at a certified independent laboratory in terms of the relevant SABS standards.

“The results were rather shocking. We selected 18 samples of PVC pipes at random from eight different manufacturers, all of them carrying the SABS mark and clearly identified by trade or company names. Of those pipes tested, at least 56% of those produced by non-Sappma members failed, while none of those produced by Sappma members failed,” he notes.

After the results of the first round of tests had been released, Sappma repeated the survey at the end of 2011, again acquiring pipes at random, although a much bigger sample size was used.

“We have found that a considerable number of the pipes tested still fell short of the industry standards. However, we are pleased to report that there seems to be a significant improvement since the previous survey,” Venter adds.

While Sappma does not claim that all pipe produced by its members will be 100% faultless all the time, Venter points out that the results of the first round of tests do seem to indicate a trend in the setting of and adhering to industry standards.

“We hope the problems picked up are only neglect and ‘night-shift’ problems. Some problems might have occurred as some companies are trying to save on materials and costs, purposefully using less material than is required to manufacture pipes. If you cut down on your wall thickness, your costs go down and you can compete, which creates an uneven playing field,” he notes.

Meanwhile, Venter explains that Sappma has a strict code of conduct, which the CEO of a company needs to sign on becoming a member of the association, while pipe manufacturers need to sign a letter of undertaking. “We also perform factory audits, while unannounced sampling keeps our members on their toes. There is great peer pressure in the association to conform to standards, and this differentiates Sappma members from non-Sappma members,” he adds.

“In the interests of the consumer and the long-term integrity of the infrastructure, Sappma will continue with these market surveys. We are confident that independent tests such as these will increase the public’s awareness of quality issues, which will ultimately raise the level of responsibility of manufacturers,” Venter concludes.

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