Walinga AL 1314, Operator'S Manual

Page: 9 / 18

9
5. AIRLOCK MAINTENANCE
Wear tip and wiper blade adjustment are on-going maintenance items. They must be scheduled for
attention at regular intervals. Correct adjustment of tip and wiper blade clearances is essential to
ensure efficient operation. Excessive clearances between rotor tips and airlock casing wilt reduce
performance and increase both the rate and non-uniformity of wear. By following the procedure below
you will achieve a consistent result each time the airlock is adjusted. Don't be tempted to take short cuts
- performance will suffer.
- WARNING-
ISOLATE THE AIRLOCK FROM POWER SUPPLY
BEFORE CLEARING or ADJUSTING
Ensure that you have clear access into the top inlet of the airlock unit before attempting to adjust wear
tips. Remove the unit from its mounting point if necessary. Note that two (2) sets of feeler gauges will
make airlock tip adjustment easier, faster and more accurate. You can also use shim metal of the
specified thickness as an alternative to feeler gauges.
5.1 Tools Needed For Servicing Blade Tips
•
3/8" Socket Ratchet Arm
•
3/8" Socket Extension (30cm)
•
¼ inch allen key to suit Tip Retaining Screws
•
Wear Tip Retaining Screws (phillips head) &
Washers if existing screws are damaged.
•
3/8" socket driver to suit ¼ inch allen key
•
Feeler Gauges (2 sets) or Shim Metal Sheet of
specified thicknesses.
•
Permanent Marker Pen
•
Small Pry Bar 20 in (50 cm) long
•
2 x 1/2" (50mm x 13mm) ring/open end
spanner
•
Scraper (to remove flange sealant)
•
Flange Sealant (eg silicone-based) or
Gaskets. Ensure that silicone-based sealants
are accepted for use in your industry.
Note:Tip Retaining Screws, Shim Metal
&
Spring
Washers are available from Walinga Inc.
5.2 Replacing Damaged Blade Tips
If one edge of an airlock blade tip is damaged it
may be possible to
reverse it and use the other
edge. Stainless steel tips may be re-ground to a
'true' edge - this may be repeated until no
adjustment is left in the screw slots.
If tips are badly damaged - replace them. Always
check the condition of replacement tips before
installing. They must not be bent and all four edges
must be true and undamaged.
(a) Loosen and remove tip retaining screws using
the ¼” allen key then remove tip from
casing – bottom ports on Blow-
Thru units are a convenient removal
point.
(b) Insert new or reversed tip and
measure clearances between tip
ends and end plates.
File or grind the ends of new tips if
necessary to ensure that the tips are
not longer than the rotor blades.
(c) Fix tips loosely to rotor blade with tip
retaining screws. Follow the
adjustment method in following
section to set correct clearances
between tip edge and casing.