NPK M35G, Instruction Manual

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65
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JAW INSPECTION AND MAINTENANCE
JAW CONTACT AREAS
S and G JAW CONTACT AREAS
In contact areas of jaws, hardfacing (we3) may be added to increase the wear life of
these surfaces for hardfacing instructions, see the JAW and TOOTH REBUILD
PROCEDURE.
S JAW
G JAW
K JAWS: Several surfaces of the K jaws have been hard faced in contact areas.
Hardfacing (we3) may be added to increase the wear life of these surfaces. The best
time to rebuild them is as soon as the hard face pattern is worn off. If the hard face
pattern is completely worn, the surfaces should be rebuilt and hard faced such that they
are even with or slightly above the adjoining blades. See HARDFACING K JAWS .
HARDFACING: K JAWS
If hardfacing is to be performed, the jaw must be preheated to 300° - 400°F (150° -
200°C) before hardfacing is applied. Failure to preheat the tip area will cause the
hardfacing to crack and chip off prematurely. Using a suitable hard face rod, apply the
material in stringer beads vertically on the front and sides of the piercing tip and parallel
to the moveable jaw on the lower face of the piercing tip. This pattern will allow for the
most efficient piercing and the least amount of interference. Peen after each pass and
maintain inner pass temperature. DO NOT APPLY MORE THAN TWO (2) LAYERS
OF HARD FACE MATERIAL!