Finn A2548-001, Operator'S Manual

Page: 28 / 133

22
BLOWER COMPONENT
BLOWER COMPONENT OVERVIEW
Please examine the blower for any damage, and if any damage is found, report it immediately
to Finn Corporation. The blower component used on the Finn Material Blower is built to exacting
standards and, if properly maintained, will provide many years of reliable service. Read and follow
every step of these instructions when maintaining the blower.
NOTE: Record the blower model and serial numbers in this instruction manual. Use this
identification on any replacement part orders, or if service or application assistance is
required.
To permit continued satisfactory performance, a blower must be operated within certain approved
limiting conditions. The manufacturer’s warranty is, of course, also contingent on such operation.
The maximum pressure differential is based on the difference
between the inlet pressure and the outlet pressure. The maximum
pressure differential shall not be exceeded. Exceeding the maximum pressure differential
will cause serious damage to the equipment and could cause bodily injury.
The maximum allowable working pressure (MAWP) is based on the
absolute pressure of the blower housing and is NOT the maximum
allowable pressure differential. Exceeding the MAWP will cause serious damage to the
equipment and could cause bodily injury.
Special attention must be paid when a blower has a higher than
standard ambient suction temperature. Special recommendations for
operating parameters and/or additional cooling may be recommended. Consult the factory or
local representative for appropriate information.
BLOWER COMPONENT INFORMATION
This blower system is a rotary lobe blower providing positive displacement. The pumping capacity
is determined by size, operating speed, and differential pressure conditions. Blowers employ
rotors rotating in opposite directions within a housing closed at the ends by end plates.
Internal lubrication is not needed, as there is no moving contact. Clearances between the rotors
during rotation are maintained by a pair of accurately machined helical timing gears, mounted on
the two shafts extended outside the air chamber. The intermeshing rotary lobes are designed to
rotate and trap air between each rotor and the housing. As the rotor lobes rotate past the edge
of the suction port, the trapped air is essentially at suction pressure and temperature. Since the
blower is a constant volume device, the trapped air remains at suction pressure until the leading
rotor lobe opens into the discharge port. The close clearances between the rotors inhibit back
slippage of the trapped volume from between the rotors, and the trapped volume is forced into the
discharge piping. Compression occurs not internal to the blower but by the amount of restriction,
either downstream of the blower discharge port or upstream of the blower inlet port.
BLOWER COMPONENT OPERATING LIMITS
MAX
RPM MAX PRESSURE
DIFFERENTIAL
MAX VACUUM
MAX
TEMPERATURE RISE MAWP
2,350 14 psi
(965 mbar)
16 inch-Hg
(542 mbar)
240°F
(133°C)
15 psi
(1,034 bar)
Maximum conditions based upon 70°F (21°C) inlet temperature and 14.7 psi (1 bar) absolute inlet
pressure.