18
A.0500.301/314.A – IM-TW/10.00 GB (0401)
2.8
Heating and cooling jackets
All TopWing models can be supplied with pump covers with channels for heating or
cooling.
The reason for having this possibility is mainly used for bringing the medium inside the
rotor case on temperature before starting up the pump. This option is not meant to heat,
cool or maintain the temperature of the pumped medium in the process. The pre-heating
or cooling of the pump cover should be integrated in the heating or cooling system of the
installation.
The pump cover with or without safety relief valve for heating/cooling is provided with
two holes drilled straight through the cover. The heat is transferred to the rotor case via
the contact faces between cover and rotor case.
The heating/cooling channels in the pump cover together with the flush holes of the shaft
seal are positioned in such a way that the required thermal effects on the built-on safety
relief valve, rotor case and shaft seal are the best.
The pressure rating at the ports of the pump cover for heating/cooling is 10 bar and
should not be exceeded without contacting Johnson Pump for advice.
For start-up and shut-down procedures where heating/cooling devices are employed, the
heating/cooling medium should circulate 20-45 minutes before start-up and/or shut-
down. When CIP/SIP cycle is employed as a part of the process, the heating/cooling
medium should continue to circulate during the cleaning/sterilizing process.
Heating/cooling jacket