Encore - Model 700 -Diaphragm Metering Pumps

• Handles capacities to 634 gph (2400 l/h), back pressures to 175 psi (12 bar).
• Non-loss-motion (amplitude modulation) variable eccentric stroke adjust mechanism renders efficiency, longevity, and reliability, as well as a smooth discharge pattern.
• Flexibility of two field convertible drives: direct coupled or pulley coupled, for an additional 4:1 turndown on stroke frequency with a standard induction motor.
• Precision-engineered liquid ends meter mild solutions, aggressive chemicals, highviscosity polymers, and slurries with greater efficiency than conventional liquid ends.
• Integral clear PVC cartridge valves for fast service with no piping disturbances and built-in visual indication of operation.
• Premium composite diaphragm design ensures high metering accuracy, even at varying discharge pressures.

Full Mechanical Movement
Unlike solenoid pumps or loss-of-motion pumps, the Encore 700 diaphragm is driven by a rotating crankshaft in which the eccentricity is smoothly adjusted during operation. There are no return springs, and the diaphragm moves with simple harmonic motion. The fluid velocity profile is sinusoidal at all stroke lengths; adjusting stroke length simply alters the amplitude of the sine wave. The graph below shows the velocity profiles for each pump type. For any given output, the areas circumscribed by each curve are identical.

Solenoid Pumps
The most simple and economical type of pump, these provide a pulsed fl ow with huge pressure spikes, considerable noise and wear.

Lost-Motion Pumps
These motor-driven pumps are higher in capacity than solenoid pumps, but also give rapid acceleration to the liquid at rest in the pump head due to non-continuous diaphragm motion.

Non-Loss-Motion Pumps
The diaphragm is driven by a rotating crankshaft, where the eccentricity can be smoothly adjusted during operation. There are no return springs, and the diaphragm moves with simple harmonic motion. The fluid velocity profile is sinusoidal at all stroke lengths; adjusting stroke length simply alters the amplitude of the sine wave. This design provides reliability and longevity, and pump valves operate with far greater efficiency and minimal system vibration.