I N S T R U C T I O N S
For the installation and maintenance of DS1525 - DS1550 -
DS2525 - DS2550 desuperheaters
IMI0030E.doc
Rev.4 20/08/12
20090 SEGRATE (MI)- via E.Fermi
EMAIL:
TEL.(02) 269912.1 - FAX.(02) 2692.2452
Page 13 of 17
9.1 REMOVAL
Before removing the desuperheater from the system, check that the vapour and water pipes are
completely depressurised, drained and bled. Bleed and remove the air supply line to the instrumentation.
Slacken the studs on the water and vapour flange and remove the desuperheater from the system. It is
advisable to move the unit to a workshop equipped with workbench and vice. Lift the unit using suitable
slings wrapped round its body. Do not attempt to lift it by the actuator or any of the other accessories. The
coupling of the plunger varies according to the type of actuator installed.
9.2 DISASSEMBLY
The desuperheater can be disassembled more easily if it is positioned horizontally with the section of the
body extension firmly gripped in the vice. Grind the weld points on the nozzle, with a standard angle
grinder. Check that the weld has been sufficiently removed to allow unobstructed rotation of the tightening
ring. Unscrew the tightening ring by turning it anti-clockwise. Note that the body extension has a right-
hand thread. To facilitate removal of the ring, tap it gently with a hammer. Note that the spray cylinder has
a left-hand thread. In the event of difficulty in removing the tightening ring, grind it at two diametrically
opposed points. Take care not to damage the thread of the body and of the cylinder (see Fig. 6).
Fig. 6
9.3 SPRAY
CYLINDER
Once removed, inspect the inside of the cylinder and check for any surface scratches of marks, which can
be removed by polishing or grinding. The bore of the cylinder must not exceed 32 mm for the
DS1525/DS2525 model and 45 mm for the DS1550/DS2550 model, with maximum out-of-round of 0.25
mm. Any debris must be removed from the nozzles with a compressed air jet. Inspect the nozzle outlet
holes. These must show no signs of elliptical wear, roughness or damage that could adversely affect their
performance. Thoroughly clean the thread of the cylinder, filing it with a small file where necessary.
