CSF Inox CN 2, Инструкции по установке, эксплуатации и техническому обслуживанию, Страница: 8 / 16

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8.3 OPERATING CHECKS
- If the pump does not generate the required discharge head rapidly, stop and repeat the priming opera-
tions.
- If the discharge gate valve is opened more than necessary, i.e. further than the specified working point,
and the pump is operating with a lower discharge head than that required, there will be an increase in
delivered capacity and absorbed power. If this occurs, throttle the discharge until the required head and
capacity values are obtained.
- If the discharge head generated by the pump is greater than that required, the diameter of the impeller
can be reduced. If, on the other hand, the discharge head is lower than required, with the same capacity,
it will be necessary to install a larger diameter impeller (if the one fitted is not already the largest available)
and probably also a higher power motor.
- The pump must operate smoothly and without vibrations.
- Do not operate without liquid and in any case avoid prolonged operation with the discharge gate valve
closed.
- Check that the suction liquid level is always sufficient to guarantee an adequate energy load for normal
operation of the pump.
- Mechanical seal: check that there is no leakage along the shaft.
9 SEALS
The CN centrifugal pumps are fitted with mechanical seals . The type of mechanical seal and material
are chosen according to the liquid to be pumped.
9.1 MECHANICAL SEALS
A mechanical seal is a device intended to retain fluid and prevent it from escaping from the pump.
The seal consists of two sliding surfaces, with one rotating relative to the other, held in axial contact by
the pressure generated by the fluid (hydraulic force) and by components such as springs or bellows (me -
chanical force). Mechanical seals are generally cooled by the fluid itself. The materials used are selected
in relation to the characteristics of the fluid used, the operating conditions in which the seal is installed
and the performance required.
WARNING Before using the pump with products which are not mentioned in your order, check that
the seal type suits the new product to be pumped.
Different types of seal are available with CN centrifugal pumps:
EXEC. "T"
- Internal mechanical seal "T . ."
The rotary mechanical seal is internally mounted to ensure effective
lubrication, cooling and consequently minimised wear. The seal
type, face materials and elastomers are chosen from a range of
several options, to suit the nature of the product being handled
and the specific application requirements.
EXEC. "TH."
- Internal mechanical seal "TH ."
Protected spring and hydraulically balanced; especially suited for
high cleanliness, vacuum and semi-viscous product applications.
Easy to clean with CIP, it is perfect for use with foodstuffs, sanitary
products, pharmaceuticals and wherever process sterilisation is
a requirement.