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fig 10

Opening the plate heat exchanger


When opening and assembling the heat exchanger observe the following:
• Measure and note the actual “A” size;
• Use the correct tools and lubricant;
• Shut down the heat exchanger as described under 7.3;
• Make sure the heat exchanger cools down (<40 ºC);
• Ensure there is no pressure on any part of the unit;
• Clean the tie (clamping) bolts and grease the threads;
• Loosen the tie clamping bolts equally in the correct order (fig. 10) i.e. that
the follower shall have a parallel opening motion;
• Pull the follower back towards the column;
• Remove the plates without damaging the gaskets.

CAUTION:

Ensure unit is depressurized and drained of hot and/or aggressive product before unit
is opened to prevent personal injury.

CAUTION:

Sharp edges. When handling plates, gloves should be worn.

Recommendation:

Mark the plate package before opening.
You could mark the plate package with a diagonal line on the outside fig 10a, or number
the plates in sequence.

Cleaning the plates

CAUTION:

Always wear gloves and eye goggles when using cleaning detergents.
Use nylon or other types of “soft” scrubbing brushes with detergent.
Never use a metal brush, steel wool or sand/glass paper.
This will damage the passivation film of the plates.
Use Acetone or other types of solvents which do not contain chlorine to remove old gasket
glue. Alternatively use a ”lowtemp.” gas flame softly heating the reverse side of the plate.
Do not use any other type of gas which may produce a “harder” flame.
Remember ventilation. Boiling water can be used with some success.
Consult a cleaning specialist for a suitable choice of detergent. Ensure that all detergents
used are compatible with the plate and gasket material before use.


In case plates are removed for manual cleaning, make sure they are re-fitted in the same
order.
Always remove plates one by one and number them!
A high pressure cleaner can be used but with absolute care and never add abrasives.
If the scaling or organic layer is thick the plates can be put in a barrel with qualified
cleaning material.
Before fitting chemical cleaned plates they need to be thoroughly rinsed with fresh
water!

Important:


Cleaning is an important part, influencing the effectiveness of the plate heat exchanger.
Insufficient cleaning can have the following results:
• too low circulation flow;
• insufficient thermal output;
• life time of the heat exchanger will be shortened.
If a plate has to be renewed because of serious damage, the plates next to this plate
normally need to be replaced.