Abnormally Large Pipe Seal Manufactured By Truco Extrusions A large sewerage pipe that needed replacing due to age posed a challenge for Amiantit Pipe Systems Africa, because modern concrete pipes use small, sophisticated seals, whereas this pipe required an unusually large pipe seal. Due to its experience in manufacturing pipe seals of all sizes, Truco Extrusions was awarded the order by Amiantit Pipe Systems Africa. The manufacture of the large SABS 974-approved rubber pipe seal posed two challenges: the uncured, soft rubber compound, with low filler content to support or strengthen it, could easily be deformed during extrusion. Also, the large size of the cord meant that the weight of the product could cause the product to deform on the conveyor belt before curing took place. The 1 700 mm long and 34 mm ID pipe seal weighed 5,5 kg when finished. "We used a standard process to extrude through the salt bath, while also attempting to extrude at a lower temperature so that the chances of the product deforming would be diminished," informs Bradley Schwartz, General Manager, Truco Extrusions.