4.2Pump Handling Precautions
•Do not stop pump without opening discharge first:
When stopping pump operation, first release pressure in the discharge line & then shut off supply air pressure. Residual pressure in the liquid discharge piping may result in deformation of the bellows due to the force of hydraulic pressure.
•Do not suspend operation for extended periods with liquid remaining in pump chamber: Suspending pump operation for extended periods may allow permeation of gas into air chambers & piping. This may cause corrosion of pneumatic components. To prevent this problem, purge air from the air chambers to prevent corrosive gas
•During pump operation:
Ensure suction or discharge line valves are fully opened during pump operation. Never close a suction or discharge line valve during operation.
•Pump at halt:
Do not supply air pressure to both air chambers simultaneously during operation or while the pump is idle. Some types of double solenoid valves cause pressurization of the two air chambers while the valve is idle. Do not use this type of valve with F Series pumps. Do not supply air pressure to either air chamber when the pump is idle.
•Lifting pump:
Do not lift the pump by the suction or discharge tubing while installing or removing the pump.
•Pump stroke speed:
Air bubbles sucked through pump suction piping could cause an air lock condition and the stroke rate to rise to an abnormal level. Safety measures should be taken to avoid running the pump above its maximum stroke speed. See page 11 for details.
80 spm............. 40 liter models
120 spm........... 2, 10, 20 liter models
•Supply air pressure:
Any fluctuation in supply air pressure or volume causes a change in pump discharge. Install a regulating valve to stabilize supply air pressure.
Regulate supply air pressure below maximum settings for longer life and protection of the bellows. Maintain differential pressure (supply air vs. discharge pressure) below 14 PSI (1 kg/cm2) to maximize pump service life.
•Liquid temperature range:
Temperature range of the liquid must be maintained within the specified temperature range for the pump model. (See Specification Table)
•Handle proximity sensor cables with care
When wiring or adjusting the sensor, take care not to twist or bend the cable excessively, as this may cause damage to the cable leads or the internal switch connection.
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