Figure 4-5. Dipper teeth, removal and installation. .
cribbing at door end, allowing crewman room to drive
(3) Install
remaining
teeth
in
a
similar
tooth locking wedge from tooth (fig. 4-5).
manner.
(2) Use drift punch ,or other suitable tool at
small point (bottom of wedge), then drive upward until
4-8. Dipper Trip Mechanism and Trip Lines
wedge is free of tooth.
(3) Loosen tooth in socket with side-to-side
a. General. The dipper trip mechanism (fig.4-6) is
taps of hammer, then remove defective tooth.
used for opening the door of shovel dipper only, but
(4) Remove remaining teeth in a similar
once installed on main hoist drum shaft, need not be
manner.
removed when shovels is converted to any other front
end arrangement. The boom trip line, consisting of
b. Tooth Installation.
chain from bucket door latch to dipper handle trip lever;
(1) Clean tooth and wedge socket, insert
trip line from trip lever over idler sheave on shipper
tooth in position, then drive tooth until it is seated in
shaft, through equalizer sheave on equalizer bracket
socket.
back to take up drum on shipper shaft (fig. 4-7). The
(2) Position tooth locking wedge and drive it
revolving frame trip line runs from equal-
into place until tooth is secure.
4-6
