NPK PH1 - Maximum Tool to Tool Bushing Clearance

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TOOLS
MAXIMUM TOOL TO TOOL BUSHING CLEARANCE
Replace the tool bushing (BF), and/or tool (HH), when the tool to bushing gap reaches
the maximum clearance. To determine whether the bushing or tool requires
replacement, follow the instructions and charts shown below:
Step 1
Measure the tool to bushing gap (d15) with the hammer horizontal, as illustrated below.
If the clearance is at or greater than the charted maximum clearance, then move on to
the next steps.
HAMMER MAXIMUM CLEARANCE
MODEL in (mm)
PH1
1/4
6
PH2
1/4
6
PH3
1/4
6
PH4
1/4
6
Step 2
Remove the tool from the tool holder. Measure the diameter (d16) of the bearing
surface of the tool (HH), which is located on each side of the retaining pin groove. The
minimum tool diameter is compared to a new tool bushing only. If the tool is at or below
the charted value, the tool must be replaced.
HAMMER NEW TOOL MINIMUM TOOL
MODEL DIAMETER DIAMETER
in (mm) in (mm)
PH1
2.24
(57)
2.02
(51.2)
PH2
2.60
(66)
2.37
(60.2)
PH3
2.99
(76)
2.76
(70.2)
PH4
3.38
(86)
3.16
(80.2)