CIPRIANI BRAZED PLATE HEAT EXCHANGERS, Руководство по монтажу и эксплуатации

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ENGLISH
efficiency, the increase of pressure losses or the freezing of the heat exchanger operated as
an evaporator.
The precipitation of small particles can be avoided by providing high turbulence of the
flow.
Factors, contributing to the emerging of scale and other deposits in hot water supply
systems:

The quality of water (see table 11.1)

The velocity of heated water. Excessive heating contributes to the emerging of
calcium deposits.

The overly small flow of warm water in particular systems reduces the turbulence
of the flow. It is a common reason for the reduction of the self-cleaning effect. In
this case the exuding calcium is precipitating on the plates. It is very topical for hot
water supply systems.

In regions, where the content of calcium in water is high and an excessive risk of
emerging of the deposits of small particles is topical, it is recommended to desalt
and to mitigate the water.

The high temperature of plates in hot water supply systems increases the
possibility of emerging of scale and the risk of the deposit of small particles. The
temperature of the walls of the BPHE should not exceed 60°C (140°F).
10. Cleaning
The cleaning of the BPHE should be regularly performed to avoid the emerging of any
deposits in the channels of the heat exchanger. The cleaning must be performed in counter-
current flow regimen, using special cleaning agents and weak acids. It is necessary to check
the chemicals and cleaning agents for the reactions with copper and stainless steel. After the
cleaning the BPHE has to be rinsed with clean water.
It is necessary to obtain full information on the substances from the manufacturers of
the cleaning agents, to verify whether the substances are capable to have an impact on the
materials of the BPHE. The cleaning has to be performed under the instructions of the safety
and accident prevention, and corresponding to the recommendations of the manufacturers
of the cleaning agent.
Before using the cleaner, check the stability of the materials to its aggressive action. The
noncompliance to these conditions might lead to the damage of the BPHE.
11. Corrosion
The brazed plate heat exchanger consists of brazed corrugated plates made of
stainless steel and copper braze. It is important to avoid factors contributing to corrosion of
steel and copper, as well as contributing to the washing out of copper during the
exploitation. The noncompliance to these conditions might lead to the damage of the BPHE.