THE IMPORTANCE OF OPTIMISING SUMP DESIGN FOR THE RELIABLE OPERATION - PowerPoint PPT Presentation

THE IMPORTANCE OF OPTIMISING SUMP DESIGN FOR THE RELIABLE OPERATION OF ROTODYNAMIC PUMPS Steve Graham – Sales Director Richard Brewis – Project Engineer

ENSURING RESILIENCE IN A PUMPING STATION A pumping station is  Expensive to build  Expensive to run, and  Even more expensive when it stops running 2

WHAT ARE THE NEEDS OF A PUMP? Pumps need smooth and uniform liquids • Adequate suction pressure (NPSH) • Air entrainment • Pump pre-swirl • Uneven velocity profile • Surface and submerged vortices • Unstable flows 3

HOW DO WE ENSURE WE MEET THESE REQUIREMENTS? There are a lot of guides to sump design Experience shows us that these alone are insufficient to guarantee complete success The best solution is the modelling process, which: • Not only identifies potential problems • But also develops solutions before construction begins 4

THE FIRST CRITERIA FOR CONSIDERATION  NPSH  Geometry  NPSH margin  3% head drop 5

CAUSE AND EFFECT  Insufficient NPSH  Cavitation  3% head drop  Indication of cavitation  Impact of cavitation 6

OBSERVATIONAL ANALYSIS  Pump pre-swirl  Dramatic impacts and effects  Direction of rotation  Loss of efficacy  Driver overload  Catastrophic failure 7

EFFECT OF SPECIFIC SPEED 8

UNIFORMITY OF DISTRIBUTION  Velocity distribution  Effects of hydraulic imbalance  Reduced output  Vibration increase  Damage and failure 9

ASSESSING AIR ENTRAINMENT  Velocity distribution  Effects of hydraulic imbalance  Reduced output  Vibration increase  Damage and failure 10

VORTEX TRACING  Surface and submerged vortices  Key considerations  Pre-swirl  Air entrainment  Impeller imbalance 11

MEASURABLE BENEFITS  Reducing risk  It costs more to correct than prevent  Impacts longevity and consistency of performance  Marginal issues are low on visibility and can be high on cost  Early involvement makes all the difference  Collaboration is key 12

THE IMPORTANCE OF OPTIMISING SUMP DESIGN FOR THE RELIABLE OPERATION OF ROTODYNAMIC PUMPS ANY QUESTIONS? Steve Graham – Sales Director Richard Brewis – Project Engineer