Page 188 - FanPedia - By Twin City Fan and Blower

FAN-PEDIA SPECIAL CONSTRUCTION

Published by
Twin City Fan & Blower NOMINALLY LEAK-TIGHT
©2017 TCF.COM

Continuous Weld GENERAL INFORMATION
> Weld locations vary by model
A fan generally cannot be constructed to be totally leak tight. Hence
Gasketing the term “Nominally Leak Tight” is used. This type of construction is
used to reduce leakage to within acceptable levels decided upon with
> Double gaskets required the customer. Fans are tested at the shop with a Soap Bubble Test to
check for leaks.
Shaft Seal Fan leakage refers to air (or other gas mixture) either leaking into
the fan housing or out of the fan housing. Leakage in or out depends
Drain on air pressure. When the air (or gas mixture) mixes with hazardous
> Pipe Coupling Type with Plug contaminants, excessive leakage can be dangerous. Excessive leakage
can waste energy, be an environmental or safety hazard, damage fan
bearings or create excessive noise.

- Fan Construction
> Arrangements 1, 8 and 9 only
> Solid drive side on housing (no drive plates)
> Not recommended for applications over 600 F
o
> Split housings not recommended
> Bolted connections must have close centered hole patterns (3”
to 4” centers) Includes: inlet and outlet flanges, access doors,
cover plates, inlet funnels, split housings, etc.

- Gasketing
> Use on all connections: inlet/outlet flanges, funnel, inlet plate,
access doors, split housing, etc.
> Split housings require centering plate to seal open areas by
shaft seals and inlet funnel or plate

- Shaft Seals (Fan Shaft - do not use shaft sleeve & cap)
> Lip type
> Stuffing Box (Graphoil) type
> Double Ring Mechanical type (Double Carbon Ring)

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