PennBarry TUB User Manual

Sample Specifications

TUB - Tubular Centrifugal Fan

General – Furnish and install, as shown on the plans,

PennBarry Tubular Centrifugal fans of the non-overloading
design and of the arrangement indicated (1, 3, 9). Unless
otherwise directed, fans shall conform to the layout on the
drawings.

Fans shall be constructed of low carbon steel and painted with
an approved coating. Each fan shall receive a documented
inspection by a qualified inspector before leaving the factory.
The inspection shall include welding, dimensions, bearings
and overall workmanship.

Performance – Fan air performance shall be based on tests

conducted in accordance with AMCA Standard 210. Fans shall
be non-overloading and shall have a sharply rising pressure
characteristic extending through the operating range and
continuing to rise well beyond the efficiency peak to assure quiet
and stable operation under all conditions. Horsepower
characteristics shall be truly self-limiting and shall reach a peak
in the normal selection area.

Wheels – Wheels shall be in accordance with the standard

sizes adopted by AMCA for tubular centrifugal fans. Wheels shall
be the high efficient, non-overloading airfoil type only. Airfoil blades
shall be die-formed, double-surface type blades continuously
welded (stitch welding unacceptable) to a hub plate and wheel
cone. All fan wheels shall have tapered, smooth flowing, wheel
cones (flat wheel cones unacceptable). The standard coating
shall be an industrial alkyd enamel.

Shaft and Bearings – Shafts shall be AISI C-1045 hot rolled

steel turned, ground and polished. The shaft’s first critical speed
shall be at least 142% of the fan’s maximum operating speed.
This critical speed will refer to the top of the speed range for the
fan’s AMCA class.

Bearings shall be designed for heavy-duty service with a
minimum L
based on the maximum operating speed of the fan’s AMCA class,
the operating temperature of the fan and the horsepower.
Bearings shall be heavy-duty, self-aligning pillow block type.
Pillowblock bearings shall be either single row ball or double
row spherical roller type.

Balancing – Wheels shall be dynamically balanced, individually

to ANSI S2.19, G6.3. Assembled fans shall then be dynamically
balanced using a vibration analyzer to measure velocity. The
final reading shall not exceed 0.1 inches per second at the fan
shaft speed. The exact level of vibration shall be recorded on the
fans as proof of the final dynamic balance at the factory.

Accessories – Accessories shall be provided as called for in

the plans and specifications. Optional accessories include belt
guard, weather cover, bolted access door, quick open access
door, drain, variable inlet vanes with stainless steel rods, inlet
companion flange, discharge companion flange, inlet screen,
discharge screen, shaft seal, discharge cap, curb cap, spark
resistant construction and vibration isolators.

life of [40,000] [80,000] hours. This performance is

10

Sound Power Levels – Manufacturer shall provide sound

power ratings in the eight octave bands. Sound power levels
shall be based on AMCA Standard 301. Sound power ratings
shall be in decibels referenced to 10

Submittals – Submittals for approval of equipment shall

include ________ copies of outline drawings, sound power
ratings and pressure-volume performance curves showing point
of operation.

General Construction – Housings shall be of heavy gauge

steel, structurally reinforced and suitably braced to prevent
vibration or pulsation, and shall be arc welded throughout. Lifting
lugs shall be welded to the housing to facilitate handling of the
fans. Straightening vanes shall be standard construction to
assure maximum efficiency and lowest noise levels.

Trak SwingOut – The entire rotating assembly, including the

wheel, bearings, shaft, motor and pulleys shall be mounted on
a single, hinged SwingOut door to eliminate the need for
disassembly for servicing or cleaning.

Inlets shall be fully streamlined and the inlet cone assembly
shall be removable through the SwingOut servicing door. The
inlet cone shall be designed to overlap the wheel cone to
minimize air bypass and noise levels and maximize efficiency.
The wheel and inlet cone overlap shall be established by
positioning the inlet cone into the wheel, eliminating the need to
raise and lower the heavy door and rotating assembly into place.
The inlet cone shall retract by means of a handle located on the
outside of the unit. In its retracted position, the inlet cone shall
permit free clearance for the door and rotating assembly to swing
in an outward direction, minimizing the force needed to break
any coating seals which may develop inside the fan during
operation. A roller on the bottom of the door and a roller track on
the housing shall be provided to allow easy door closure and to
assure proper wheel alignment.

Door gasketing shall be heavy duty, neoprene compound,
extruded P-mold design to ensure gas-tight construction and
prevent leakage during operation and washdown cycles. A
positive locking mechanism shall be provided to prevent
accidental opening of the SwingOut door by unauthorized
personnel.

MaxAccess – Two hinged SwingOut doors, reinforced with

steel ribs, shall be installed to allow direct access to the
airstream. All sizes except 222 shall be constructed with a large
wheel removal panel in addition to the SwingOut doors.

Inlets shall be fully streamlined and the inlet cone shall overlap
the wheel cone to minimize air bypass, reduce noise levels,
and maximize efficiency.

-12

watts.

44

PENNBARRY