PMB masters shrinkage control
December 1st 2007

Precision engineered masterbatch with a predictable rate of shrinkage from PMB has provided LINPAC Allibert with the solution to a complex processing challenge. Blow moulded base units for supermarket roll cages are manufactured at the company's Winsford plant and ensuring a perfect fit with the steel components was critical. Masterbatch was used to help control shrinkage and ensure that the various different coloured bases remained within tolerance. Measuring approximately 1m2, the roll cages were previously of all steel construction, it was decided to move to plastics as the steel bases were vulnerable to transit damage. However, larger blow mouldings can present processors with a challenge in ensuring acceptable levels of shrinkage and a perfect fit with other components. "PMB worked with us to ensure that the masterbatch did not just provide a perfect colour match for our customer, but also helped to overcome our processing issues," says John Tilley, purchasing executive.