Hyd-Mech PH 211, Use And Maintenance Manual

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Use and maintenance manual PH211
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 Molyb-
denum
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
HRC 67--68
HRC 45--50
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 PH211 are 2.085 x 20 x 0,9 mm.; the length can vary
between 2.075 mm. and 2.095 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:
H
tooth cutting angle (rake), can be 0 ˚ or positive;
H
the tooth pitch can be constant or variable;
H
the set, i.e. the various teeth alignments, have many possible configurations.
N.B.