INSTALLATION, OPERATION and MAINTENANCE MANUAL | 61
12.6. Regular APV DuoSafety Internal Inspection
Regular internal APV DuoSafety plate pair inspections must be made. SPX FLOW
recommends at least an annual inspection for AISI316 heat exchangers. The APV
GPHE must be opened and the APV DuoSafety plate pair separated. Carefully check the
inside surfaces for traces of the product/ liquid processed in the APV GPHE. If visual
inspection of the surface is difficult (e.g., because the product is transparent) then it is
recommended that indicator dye is sprayed onto the inside surface of the plate pairs.
Fouling between the APV DuoSafety plate pair indicates that at least one of the APV
DuoSafety plates has a defect. In this case, both plates in the APV DuoSafety plate pair
must be removed from the APV GPHE.
12.7. Plate Replacement
Before replacing a plate in a heat exchanger, the new plate must be checked against
the plate it is replacing. The new plate must be identical in every way.
The customer drawing provided with the heat exchanger provides information on the
material, port punching, gaskets, and location of each plate in the heat exchanger.
Note: During the installation, always alternate left and right hand plates. For
simplification only, whole blocks of identical left or right hand plates are shown on the
plate arrangement diagram. The total number of each is given. Vertical flow plates may
be changed from left hand to right or vice versa by turning the plate over.
12.8. Gasket Replacement
For ordering of genuine APV spare parts and for re-gasketing, refer to section 14.0:
“Spare Parts, Identification and Ordering”.
Plate heat exchanger gaskets are attached to individual plates by one of two methods,
glued or clip in. Glued in gaskets are attached by a thermoplastic adhesive which is
heat cured for maximum strength. The Paraclip clip in gaskets are attached to the plates
by small nubs around the perimeter and port areas of the gasket which snap into
matching holes on the plate. The EasyClip clip in gaskets are attached to the plates by
tongues around the perimeter and port areas of the gasket which snap into matching
slots on the plate.
Removal of old gaskets
To remove clip in gaskets, the gasket may be carefully pulled from the plate. If the
gasket is to be reused, pull slowly to avoid tearing off the clips or stretching the gasket.
To remove glued in gaskets, the bond between the plate and gasket is softened by
using a propane torch to heat the plate from the non-gasketed side directly behind the
gasket. As the adhesive softens, use pliers to pull the gasket from the groove. Continue
this process until the entire gasket has been removed.
To Next Page
Loading...