Hyd-Mech DM-1215, Use And Maintenance Manual

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Use and maintenance manual DM-1215
Blade structure
The most commonly used blades are the bimetal types, i.e. manufactured with a
silicon steel body and having a high fatigue strength, and super high-speed steel
teeth; the two parts are welded by electronic or laser-welding.
Standardised teeth types are termed M2 and M42; the difference being that M42
teeth are harder due to the addition of cobalt to the steel used to make the teeth.
Key
Mo Molybde­
num
Ni Nickel Si Silicon V Vanadium W Tungsten
Al Aluminium C Carbon Co Cobalt Cr Chromium Mn Manganese
HSS M2
HSS M42
C Mn Si W Mo V Ni Co Al HRC Cr
0,47 0,75 0,22 1,00 1,00 0,12 0,52 0,08 45 − 50
0,85 0,25 0,30 4,15 6,37 5,00 1,92 64 − 66
1,07 0,25 0,20 3,75 1,50 9,50 1,15 8,00 67 − 69
ËËËËË
ËËËËË
ËËËËË
ËËËËË
ËËËËË
ÊÊÊÊ
ÊÊÊÊ
ÊÊÊÊ ÏÏÏÏÏ
ÏÏÏÏÏ
HRC 67 − 68
HRC 45 − 50
ËËËËË
ËËËËË
ËËËËË
ËËËËË
ÊÊÊÊ
ÊÊÊÊ
ÊÊÊÊ ÏÏÏÏÏ
ÏÏÏÏÏ
HRC 65 − 66
HRC 45 − 50
TYPE OF
BLADE
The numbers in the columns indicate the % content of the element in the steel.
Blade types
The blades mounted on the DM-1215 are 3.440 x 27 x 0,9 mm.; the length can
vary between 3.420 mm. and 3.460 mm., thanks to the blade tensioner device. The
blades, however, apart from size and tooth pitch, are differentiated by other
geometrical characteristics which determine their specialised uses:
tooth cutting angle (rake), can be 0
°
or positive;
the tooth pitch can be constant or variable;
the set, i.e. the various teeth alignments, have many possible configurations.
N.B.