Page 185 - Practical Machinery Management for Process Plants Major Process Equipment Maintenance and Repair

Positive Displacement and Llynumic Blowers 157

For double-width fans, the linkage from the vanes on each side is con-
nected to the jack shaft that mounts on the fan housing. On double-width
fans, if the jack shaft levers connecting each set of vanes do not line up
with the connecting rods, the lever has been moved to protect it during
shipment. Remove the pin from the jack shaft, slide levers back into posi-
tion, carefully lining up the pin holes in levers, and replace the pin. At-
tach the connecting rods from individual mechanisms.

Expansion Ducts and Joints

If the fan being erected is to operate at high temperatures, expansion
joints are absolutely necessary at the fan connections. They allow for ex-
pansion of the fan housing and connecting ductwork without distorting
each other. Remove any shipping braces from the expansion joints before
operating the fan and provide for fan expansion in setting the housing
foundation. Do not use drift pins, “come-alongs,” or any other means to
force connections of ducts, fan housings, or inlet boxes.

Circulating 011 Lubrication Systems

If you specified a circulating oil lubrication system, detailed drawings,
and erection, startup, operation and maintenance instructions should be
included in the shipping data package.
During erection of the oil piping, be sure that the system is free from
dirt, grit, weld spatter, or shavings. The piping system must be thor-
oughly cleaned and flushed before connecting to the bearings. Clean the
filters before initial start-up.
After the selection of which pump is to be used (if a two-motor/pump
system), the motor is turned on to activate the pump. Oil passes from the
tank through the filter element, pump, pressure relief valve, oil cooler,
sleeve bearings, and then by gravity back to the reservoir tank.
The circulating oil system must be operating before the fan can be
started. Depending on the system specified, any malfunction in the sys-
tem, low oil pressure, high temperature, etc., may either sound an alarm
or shut down the fan. The oil system must operate 30 minutes after the
fan is shut off or until the heat in the bearings has dissipated to an accept-
able level.

Temperature Detectors
Dial thermometers screw into a tapped hole in the housing so that the
oil sump temperature of bearings can be measured. See Figure 4-17.