Hyd-Mech PH 211, Use And Maintenance Manual

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Use and maintenance manual PH211
SOLUTION PROBABLE CAUSE PROBLEM
Broken teeth
'
Cutting pressure too high
.
Check and set to correct
pressure
'
Tooth pitch unsuitable
.
Teeth too close together:
change blade for one with a
coarser tooth pitch
'
Swarf welded to teeth and
gullets
.
Check blade--cleaning coo-
lant jets. Check the blade--
cleaning brush. If the swarf is
not removed from the blade it
will be drawn back into the
cut and weld to the teeth,
causing tooth breakage
'
Swarf welded to teeth and
gullets
.
Check blade--cleaning fluid
jets. Check blade--cleaning
brush. If the swarf is not re-
moved from the blade it will
be drawn back into the cut
and weld to the teeth, caus-
ing the teeth to break.
'
Material defects
.
The material may have al-
tered surface areas, such as
oxides or sand, or subcooled
inclusions in the section.
These areas are much
harder than the blade and
will cause the teeth to break:
scrap or clean these ma-
terials.
'
Workpiece not clamped
.
The blade may break if the
workpiece moves during cut-
ting: check the vice, jaws and
clamping pressure
'
The blade stops in the cut
.
Cutting pressure too high:
check and restore to rated
pressure. Downstroke speed
too fast: reduce speed. Cut-
ting speed too slow: in-
crease. The blade slips on
the flywheels: either the
wheels are worn and need to
be replaced or the blade ten-
sion is incorrect (too low) and
must be re--adjusted.
'
New blade inserted in a par-
tially made cut
.
The cutting surface may
have been subjected to a lo-
calised heat--induced alter-
ation, making it harder: re-
commence cut using a
slower cutting and down-
stroke speed. A tooth from
the old blade may be left in
the cut: check and remove
before restarting work.