2. OPERATION
IOM manual Tapflo PTL Hose pumps
18
2.2.1.
Dry running
Although the pump is prepared for dry running it is important to have in mind that long periods
of dry run may cause damage to the wearing parts of the pump. What is more, an empty pump
should operate at low speeds
–
controlled by a frequency inverter.
2.2.2.
Dead head
The pump cannot operate with closed discharge valve. This may lead to pump malfunction and
cause injury to operators in the vicinity of the pump.
The discharge pressure can never exceed pump rated pressure.
2.2.3.
Optimization of the pump lifetime
➢
Continuous operation at higher frequency than 50 Hz will cause premature wear of the
components. As a general rule, we recommend to run
the pump at ±20% of the rated
frequency.
➢
When reducing the motor rotation speed, it is important to monitor the surface temperature
of the gear-motor and ensure that it does not exceed the nominal working temperatures
specified by the gear-motor manufacturer.
2.3.
Pump stopping
Turn off the motor to stop the pump. Close the discharge shut-off / regulation valve
immediately after. The reverse sequence is not recommendable, especially with larger pumps
or longer delivery piping. That is to avoid any problems due to water hammering.
It is therefore
advised to install a check valve on the discharge to protect the pump. If a suction shutoff valve
has been installed, it is advisable to close it completely after pump is fully stopped.
The pump should be stopped by cutting of electrical power to the motor or frequency inverter
(if used
–
at 50 Hz cool down should be set to 5 seconds).
NOTE!
Never stop the pump by completely closing the discharge valve without motor shut
down.
2.4.
Cleaning and disinfection
Cleaning and disinfection of the pump system is of greatest importance when the pump is used
in a food processing installation. Use of a pump system that is NOT cleaned or disinfected can
cause contamination of the product. The cleaning cycles as well as chemicals to use for the
cleaning vary depending on the pumped product and the process. The user is responsible to
establish a suitable cleaning and / or disinfection program according to local and public health
and safety regulations.
If the outside of the pump is to be rinsed or flushed, the power supply must be disconnected
beforehand.
2.5.
Residual risks
Even with proper application and observance of all points listed in this operating manual, there
is still an estimable and unexpected residual risk when using the pumps. It may leak, fail due to
wear, application-related causes or system-related circumstances.
Summary of Contents for PTL Series
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