preferably round-bottomed, and large enough to guard
against overflow (fig. 14-2).
The maximum or minimum slope should be
determined by the condition of the concrete as
discharged from the chute. Quality control personnel
on the jobsite should provide guidance in this area.
When possible, you should install a downpipe on
the end of the chute to help keep the concrete from
segregating when coming off the end of the chute.
Be sure to read the operators manual for the type
of concrete mixer you are operating.
attention to the following:
3. Check the water tank and meter valves of the
on-board water system for the following: operating
condition, clean tank, and all valves are clear.
Give special care to cleaning the transit mixer. At
the beginning of each workday, the mixer should be
coated with form oil to prevent cement and concrete
from sticking to the paint or bare metal. After the load
of concrete is discharged from the mixer, the operator
should wash off all excess concrete in the mixer drum
and blades, the discharge chute opening, and the
discharge chute before it has a chance to harden.
Spraying 15 to 25 gallons of water into the drum while
it is rotating will clean the inside of the drum as well as
remove all grout which may have collected in the water
nozzle during discharge. A washdown hose is provided
on the mixer to clean areas accessible from the outside.
1. Ensure the chain drip oiler is filled and turned
on at the beginning of operation.
2. Check the oil level in the hydrostatic drive unit
Consult your supervisor about any
at the sight glass.
environmental regulations that require
Figure 14-2.-Chutes used for discharging concrete.