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displacement of the crosshead and adjusting the flow. If the eccentricity between the E-type slide shaft and the
center of the eccentric gear reaches half of the maximum stroke, the pump will reach the maximum stock (i.e.,
100% of the relative stroke) and the maximum discharge flow. As the E-type slide shaft axially moves, the
center of eccentric gear will get closer to the center of the slide shaft; where both centers are overlapped, the
eccentricity of the eccentric gear will be zero, and it will be deemed as the zero point where the pump does not
discharge fluid and the pointer of the pump adjusting mechanism points at zero.
The pump stroke can be adjusted during shutdown or operation, and it will take about 1~2min to keep the pump
flow stable after adjustment. In particular, the greater the stroke change, the longer the time for keeping the flow
stable, especially for diaphragm pumps.
Each metering pump has received normal-temperature water test before leaving the factory, and is attached with
a test report. The users must retest the metering pump and recalibrate the flow curve according to the actual
working conditions , so as to regulate the flow according to such flow curve during operation.
III
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Installation
1. The pump shall be installed on a special spare concrete foundation or cast iron platform and fixed with
foundation bolts after re-calibration, and the concrete foundation shall be 50~100mm above the ground to
prevent being washed by water. At the same time, it needs to reserve enough space around the pump to
facilitate the maintenance and adjustment of the pump.
2. The diameters of the suction and discharge pipe should not be less than the diameter of the inlet and outlet
pipe of the pump, and the suction pipe should be as short as possible. If the inlet pipe of the metering pump
is too long or the viscosity of the medium is larger, the diameter of the inlet pipe should be increased,
otherwise it will affect the normal operation of the pump.
3. The connecting pipe shall be equipped with measuring instruments, such as pressure gauges.
4. Filter devices shall be installed at the end of the suction pipe.
5. The discharge pipe shall be fitted with a safety valve or a safety-relief valve (provided by the user). If you
need to reduce the pressure fluctuation at the outlet, please install a pressure stabilizer (such as a buffer)
near the discharge pipe. Safety valve and buffer tank of the pipe are important accessories of the metering
pump. The pipe safety valve is usually installed in the discharge pipe behind the centralized liquid pipe,
