PUMP REDESIGN IMPROVES CORROSION RESISTANCE AND REDUCES DOWNTIME

CHALLENGE

A desalination plant in the Middle East was experiencing high levels of corrosion on one of its pumps. Stress corrosion cracking was clearly visible in the steel ‘trouser leg’ casing. The operator asked ClydeUnion Pumps, a Celeros Flow Technology brand, to come up with a solution.

SOLUTION

ClydeUnion Pumps undertook a design review to determine where improvements to the existing pump design could be made. They used advanced 3D modelling and rapid pattern manufacturing techniques to redesign the trouser leg, as well as upgrading the material specification to cope with the harsh operating conditions at the desalination plant. The new three-part pump casing is made from Duplex stainless steel, renowned for its corrosion resistance. The redesign also uses an advanced composite material (Tufnol) between new and existing components with galvanic potential.

The use of advanced modelling and manufacturing techniques delivered significant time savings during the repair. Pattern manufacturing time was halved, with patterns completed six weeks ahead of the original schedule. Casting thickness was reduced by 20 per cent, saving on raw materials, and a net weight reduction of 10 per cent was achieved over the original design. The new three-piece pump casing offers the opportunity for future savings because the customer can be supplied with an individual section as required, instead of replacing the entire casing.