James Walker has introduced HydroSele, a shaft sealing system for Francis and Kaplan water turbines in hydropower plants across the world. Simple to install and adjustment-free, this split-type cartridge seal can be economically refurbished on site in just a few hours.
According to James Walker, HydroSele is the result of over ten years of design and development, plus long-term field trials on operational turbines. James Walker also adds that trials have shown that HydroSele works efficiently under a wide variety of conditions and can pay for itself in less than two years in terms of maintenance costs, reduced turbine downtime and power absorption.
According to James Walker, at four years, the user's total investment in cash and downtime could be just one-quarter of that for an equivalent mechanical seal.
HydroSele is a fully-split cartridge unit containing two developed sealing elements working back-to-back with flush water introduced between them. In operation, the elements are pressure-balanced and run on a hydrodynamic fluid film that provides high-speed capability with a low-level of controlled leakage.
HydroSele’s modular design enables the cartridge components and sealing elements to fit together perfectly around a turbine shaft without stripping down the housing. On-site assembly takes hours, rather than days, and all components can normally be handled without mechanical lifting gear or the fear of breaking fragile items.
As seal refurbishment is equally swift and simple, operators do not need to hold expensive stand-by sealing units in stock.
HydroSele is available for Francis and Kaplan turbines with shaft diameters of 250mm to 750mm (9.84 - 29.53 inches). Sizes in excess of 750mm are custom designed, dependent on operational parameters.
Normal maximum operating limits are l Om/s (32.8fps) shaft speed and l Obar gauge (145psig) pressure at the gland. Higher speeds and pressures may be tolerated after consultation with James Walker.
James Walker confirms that prototype and pre-production HydroSele units have run with great success for nine years on hardworking vertical and horizontal turbines. James Walker says that HydroSele is a cost-efficient answer to Kaplan and Francis turbine shaft sealing, both for installation as original equipment and retrofit by plant operators.