Alfa Laval Contherm 6X11, Инструкция по эксплуатации

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8 Inspection & Maintenance
Table 8-8. Replacing the Seal Face
Step Action
1 After removing the O-ring, chip out the damaged seal face.
Note: Use care when chipping out the seal face. Do not scratch or distort the seal shell.
2 Wash the seal shell with detergent and water to remove any product residue and/or pieces of the seal face.
Rinse thoroughly.
3
Place seal shell (without O-Ring) in an oven or other heat source such as a heating plate that will provide uniform
heating and expansion across the entire shell. Ensure precautions are taken as non-uniform or inconsistent
heating of the shell can either distort or damage the seal. If possible, seek to achieve 550°F (290°C) for 30
minutes.
4 Place new seal face on a lapping plate, with the relieved side down.
Relieved Side
5
Use heat protective gloves to remove the shell from the oven or heat source and place it over the seal face.
Press the seal shell down evenly over the seal face and rotate it to ensure proper flat seating. The thermal
expansion of the shell should allow for easy assembly. If the assembly procedure requires a high degree of
pressing force, stop and repeat above heating step with increased temperature to achieve easy assembly
with little force required.
6 Allow the assembly to cool to room temperature.
Note: Do not use water to cool the assembly as this will crack the seal face.
7
Clean the lapping seal face. Lap the seal face in accordance with the procedure provided in Table 8-9 of the
following section, Section 8.4.3.3, Lapping A Seal Face.
8 Lubricate the new O-ring with food grade lubricant. Install the O-ring into the seal. Install the seal onto the
rotor. Do not to touch the seal face! Install a new O-ring, first apply a food grade lubricant to the O-ring.
Install the seal assembly onto the rotor.
9 Test for leaks by operating the Contherm with water as the product for several minutes. If a small leak occurs,
allow the unit to operate for at least 20 minutes to permit the sealing surfaces to lap themselves for a precision
fit. If the leak continues, check and verify that the seal has been properly assembled and installed.
8.4.3.3 Lapping A Seal Face
If the seal has a slightly roughened or pitted surface, it may be possible to lap the surface and salvage the seal face. Table
8-9 provides a detailed procedure for lapping a seal face.
Table 8-9. Lapping a Seal Face
Step Action
1 Remove the seal shell assembly from the rotor.
2 Place a piece of the 30-micron film on an adequate lapping plate.
Note: Any surface other than a lapping plate will destroy the surface of the seal face.
3 Using very light, even pressure, move the seal shell, with the carbon face down, over the film in a figure “8” type
of motion.
4 Examine the surface often as the 30-micron film removes material rapidly.
5 When the defect appears to have been removed, replace the 30-micron film with the 15-micron film. Repeat the
lapping with the 15-micron film, using the same figure “8” type of motion, until the seal face is polished.
6 When the seal face is polished with the 15-micron film, replace the film with ordinary bond paper and repeat
the polishing to wipe away any remaining residue.
7 Install the seal shell assembly onto the rotor assembly. Do not touch the seal face! After installation, clean the
seal face with alcohol or solvent.
8.4.3.4 Replacing the Seal Locking Pin
When a seal leak is detected, visually inspect the Contherms
™
rotor and verify that the seal locking pin (Part Number 7403558-07)
is not broken, notched or damaged. If it is broken or damaged, follow the directions provided in Table 8-10 to replace it.
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