Alarko ALD 400 Series, Руководство по эксплуатации

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10
The recommended assembly patterns are shown in the diagrams attached to this
manual.
Precautions to Extend the Service Life of Mechanical Seal:
The mechanical seal is one of the most sensitive parts in the water booster.
Inaccuracies or inadequacies in the installation and operating conditions cause the
shaft seal to break down rapidly. The normal life of the mechanical seal is 8,000 hours
under clean, cold (20°C), solid particle-free (without sodium carbonate, calcium
carbonate) water conditions. Mechanical seal works according to the principle of
forming a water film layer between carbon and ceramic or stainless surface. This
water film layer formed during operation allows the surfaces to slide on each other
without friction. Water also serves as cooling. Lack of water film layer and the dry
running of the seal surfaces by rubbing against each other without a water layer
between them causes burns and deteriorates them within 3-5 minutes.
The mechanical seal is at great risk in the following incorrect or inadequate operating
conditions;
• If the motopump is sucking from the tank at the low level; This type of installation
should not be done. There is a possibility of leakage of the valve at the suction end. In
this case, the water in the suction pipe drains into the tank, no water remains in the
pipe, the pump runs without water.
• If there is a strainer, check valve etc. between the motor pump and the tank: If the
bottom of the tank is at the same level as the water booster base or the tank is higher
than the water booster, a check valve is not required in the suction line. The check
valve makes the water flow difficult. This is also a potential congestion point. The
strainer should be checked and cleaned frequently. Otherwise, the water flow will be
blocked and the pump will run without water or with insufficient water.
• If there is sand in the water: Sandy water will also penetrate into the film layer and
corrode the surfaces, causing the seal to deteriorate.