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| MODEL 4420-3 LOW PROFILE CRACKMETER | GEOKON
E.1.2 CRACKMETER INSTALLATION
1.
Using a masonry drill (or other suitable equipment), drill a 3/8" (9.5 mm)
diameter x 1.25" (32 mm) deep hole on each side of the crack, at a spacing
of 10.5" (267 mm).
Note:
For mounting surfaces that are smooth in texture, the reference disc
may be omitted. For installations without the reference disc only one hole
and one expansion anchor is required. The completed assembly without a
reference disc is shown in Figure 18 below.
2.
Clean out the drill cuttings and insert the anchors into the holes, slotted end
down.
3.
Insert the provided setting tool, small end first, into each anchor. Expand
the anchors by hitting the large end of the setting tool with several sharp
hammer blows.
4.
Using Loctite cement on the threads, screw the reference disc into one of
the threaded expansion anchor holes until it is tight in the anchor.
5.
Loosen the jam nuts on the oval point set screw. Using the wrench
provided, back off the set screw so that it will not make contact with the
reference surface when the gauge is mounted.
Note:
A one-inch set screw is provided for installations where 75% or more
of the displacement is anticipated to move the reference surface up in
relationship to the crackmeter. When using the one-inch set screw, the jam
nuts should be placed on the underside of the gauge, space permitting.
6.
Align the threaded hole on the cable side of the crackmeter over the other
anchor.
7.
Slide a washer over the supplied cap screw and tighten it into the expansion
anchor.
18:
FIGURE 18:
Crackmeter assembly using reference disk and two anchors
19:
FIGURE 19:
Crackmeter assembly with only one anchor and without a reference disk