Graco 3A2578B Installation, General Information, Tighten Fasteners, Tips to Reduce Cavitation

Models: 3A2578B

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Installation

Installation

Installation

General Information

The Typical Installation shown is only a guide for selecting and installing system components. Contact your Graco distributor for assistance in planning a system to suit your needs. Always use Genuine Graco Parts and accessories. Be sure all accessories are adequately sized and pressure rated to meet the system’s requirements.

Reference letters in the text, for example (A), refer to the callouts in the figures.

Variations in color between the plastic components of this pump are normal. Color variation does not affect the performance of the pump.

Tighten Fasteners

Before mounting and using the pump for the first time, check and retorque all external fasteners. Follow Torque Instructions, page 16, or see the torque tag on your pump. After the first day of operation, retorque the fasteners.

Tips to Reduce Cavitation

Cavitation in an AODD pump is the formation and collapse of bubbles in the pumped liquid. Frequent or excessive cavitation can cause serious damage, including pitting and early wear of fluid chambers, balls, and seats. It may result in reduced efficiency of the pump. Cavitation damage and reduced efficiency both result in increased operating costs.

Cavitation depends on the vapor pressure of the pumped liquid, the system suction pressure, and the velocity pressure. It can be reduced by changing any of these factors.

1.Reduce vapor pressure: Decrease the temperature of the pumped liquid.

2.Increase suction pressure:

a.Lower the installed position of the pump relative to the liquid level in the supply.

b.Reduce the friction length of the suction piping. Remember that fittings add friction length to the piping. Reduce the number of fittings to reduce the friction length.

c.Increase the size of the suction piping.

NOTE: Be sure the inlet fluid pressure does not exceed 25 % of the outlet working pressure.

3.Reduce liquid velocity: Slow the cyclic rate of the pump.

Pumped liquid viscosity is also very important but normally is controlled by factors that are process dependent and cannot be changed to reduce cavitation. Viscous liquids are more difficult to pump and more prone to cavitation.

Graco recommends taking all the above factors into account in system design. To maintain pump efficiency, supply only enough air pressure to the pump to achieve the required flow.

Graco distributors can supply site specific suggestions to improve pump performance and reduce operating costs.

Mount The Pump

To avoid serious injury or death from toxic fluid or fumes:

Ventilate to a remote area. The pump exhaust air may contain contaminants. See Air Exhaust Ventilation, page 11.

Never move or lift a pump under pressure. If dropped, the fluid section may rupture. Always follow the Pressure Relief Procedure, page 14, before moving or lifting the pump.

1.Be sure the mounting surface can support the weight of the pump, hoses, and accessories, as well as the stress caused during operation.

2.For all mountings, be sure the pump is secured with screws through the mounting feet.

3.Make sure the surface is flat and that the pump doesn’t wobble.

4.For ease of operation and service, mount the pump so air valve, air inlet, fluid inlet and fluid outlet ports are easily accessible.

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3A2578B

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Graco 3A2578B Installation, General Information, Tighten Fasteners, Tips to Reduce Cavitation, Mount The Pump