Sykes Group says its new range of Xtra high head pumps have the lowest shaft stiffness ratios in the industry, which is critical in variable and demanding pumping applications.
The company says when operating at maximum efficiency the pressure within the pump casing is balanced.
However, as the pump duty moves away from its best efficiency point, pressure becomes imbalanced, forcing high levels of load and thrust on to the shaft.
It is this radial loading that can cause shaft deflection and bending stress that can lead to premature bearing, seal and shaft failure.
A pump with a low shaft stiffness ratio is more durable and tolerant, which allows it to run multiple duties and at varied speeds.
The ratio is calculated using the length and diameter of the shaft in the calculation L3/D4. The generally accepted industry L3/D4 ratio is within the 1.5 to 2.5 range.
The company says its ratios are “outstanding” with the XH80 at 0.39, XH100 at 0.25 and the XH150 at 0.28.
The Sykes Xtra range has heads to 245m and flows of up to 150L/s.