Patterson Offers Sewage Pumps With Zero Flush Technology
Patterson Pump's The Forceline® NCS Series and Type "F" Sewage Pumps are now offered with a sealing arrangement which requires no flush water, providing substantial savings in areas of maintenance and seal flush water.
This new technology features EnviroSeal's SpiralTrac(tm) throat bushing and the Chesterton® Model 442 split mechanical seal. With this unique design arrangement, no flush water is required, saving on the initial cost of the installation as well as long term costs associated with having to flush the stuffing box. Ultimately, the pump user benefits by having extended seal life, and maintenance can be performed to the seal and stuffing box without taking the pump out of service.
The SpiralTrac is a throat bushing that takes advantage of the natural circulation of process fluid inside a stuffing box. It is placed in the bottom of the stuffing box and used with a mechanical seal. Since the fluid in the stuffing box spins with shaft rotation, the SpiralTrac takes advantage of this action to expel solids and particles from the stuffing box during equipment operation. This increases seal life by leaving a cleaner fluid in the stuffing box for the mechanical seal.
Entrained air can collect in a stuffing box either from start-up as the pump is flooded or over time from the liquid being pumped. This air will surround the mechanical seal during equipment operation as the heavier liquid centrifuges to the stuffing box wall, resulting in higher seal heat and wear. The SpiralTrac releases this entrained air out of the stuffing box through a unique air vent in its top surface.
The Chesterton 442 Split Mechanical Seal construction enables the seal to handle pressures three and one-half times higher than conventional split seals. In addition, the 442 is the only split seal specifically designed to be able to withstand vacuum in the stuffing box. This makes it an ideal seal for non-clogging solids handling pumps.
The 442 provides the sealing capability of traditional mechanical seals without the need to disassemble and realign the pump. All parts are split to slip around the shaft and assemble in place. The 442 is a dramatic time saver with fast, easy installation, plus the ability to be rebuilt quickly and easily. Downtime is minimized and driver/equipment alignment is eliminated.
This new zero flush technology is also available for retrofitting sewage, secondary sludge, effluent and other wastewater pumps, offering the same substantial savings in maintenance and seal flush water.
Source: Patterson Pump Company