Page 306 - Wastewater Solids Incineration Systems

Incinerator Maintenance 267

Repairs of these cracks can be accomplished by two different procedures. The
damaged section of the shaft can be replaced by disassembling all shafting and arms
above the failure, adding a new section, and assembling the remaining parts. An
alternate procedure is to repair in place by “cold metal stitching.” This is a procedure
of lacing together a crack by means of rectangular metal blocks (see Figure 11.4). The
metal blocks, which have a high nickel content, are peened tightly into the drilled-
out cavity of the original casting.
1.8.6 Center Shaft Shear Pin
The center shaft shear pin should be checked on a regular basis and replaced as
needed.

1.8.7 Drive Gear
Wear by the central shaft thrust bearing allows the bull gear to press against the
pinion gear. Chattering and teeth wear may result. The back side of the bull gear
teeth should be checked to ensure adequate clearance.

FIGURE 11.4 Cold-metal stitching.