Jetvac Director Peter Salomons pours silicate resin onto a fibre-glass sheet.
The Jetvac sewer cleaning company in South Africa was tasked with repairing multiple defects in a four-kilometer-long sewer pipe in Cape Town. Using conventional technology would mean installing a cured-in-place pipe lining between each set of manholes along the pipe – at a cost that would bust the annual budget for such work several times over. Instead, Trelleborg’s epros DrainPacker method offered a much more flexible and cost-effective solution.
Preparing to roll the impregnated sheet around an inflatable packer.
The epros DrainPacker system consists of two products, a silicate resin and a fibreglass sheet, which combine to make sectional repairs of damaged pipes and sewers. The resin is applied to both sides of the sheet, and once the sheet is impregnated and folded into three layers, it is rolled around an inflatable packer. The packer is lowered into the sewer pipe and pulled into position, where it expands, pressing the patch against the pipe wall. The resin cures, creating a strong and impermeable bond.
The impregnated sheet rolled around the inflatable packer.
The patch must be in place before the resin starts to cure, and the hotter the ambient temperature, the faster the products react. “The heat in Cape Town was a problem, so we specified a silicate resin with a longer reaction time,” says Andreas Bichler, Technical Leader with Trelleborg in Duisburg, Germany.
Packer and sheet are manoeuvred through a manhole into the sewer pipe.
According to Technical Leader Andreas Bichler, the liner would be left standing even if the pipe itself collapsed. The product is also unique in that its curing process can take place underwater.