The star-independent. [volume] (Harrisburg, Pa.) 1904-1917, 1914-12-31
BLOWERS AND EXHAUSTERs

Note-All blowers and exhausters
shall have all exposed collars, set
screws, shafts, couplings, clutches, keys,
pulleys, gears and belts guarded as pro
vided for by the regulation for the
transmission of power, unless other reg.
ulations have been approved by the
. Industrial Board for special cases.
Suction Test-Sufficient suction head
shall be maintained in each branch
pipe within 10 inches of the hoods to
displace a minimum of two inches of
water column in U-shaped tube.
Pressure to he taken by pressing tube
, attachment over small opening through
pipe, commonly called static method.
Tests to be made with all branches open
and unobstructed.
Piping-Round pipe shall be used
for all main duets and branch connec-
ticns, unless some other form is spe.
citically approved by the Commissioner
of Labor and Industry. All branch
| pipes must enter the main trunk pipe
at an angle of 45 degrees or less All
bends, turns or elbows in such pipes
must be made with easy, smooth sur
faces having radius in the throat of
not less than two diameters of the pipe
on which they are connected. No
branch pipe shall extend into the main
duet and all laps shall be made in the
direction of air fow
Emery wheel and bufing wheel ex-
haust systems shall be kept separate
owing to danger of sparks from the
former setting fire to the lint dust
frcm the latter, if both are drawn into
the same suction main.
The inlet of the exhauster shall be at
least 20 per cent, greater in area than
the combined areas of the several con.
nections to the hoods, and this in
crease in the main pipe shall be ear
ried proportionately throughout the en-
tire trunk line. The piping on the out
let of the fan is also to be at least
20 per cent. greater than the combined
areas of the several connections to tho
hoods.
The area of the main duet at any
point should be equal as near as pos
sible to the combined areas of all
branch pipes to that point, plus the nee
essary 20 per cent excess area. In
general not more than two branches
should be connected to section of uni
form diameter in the main duet.
The use of screens across the mouth
of branch pipes is prohibited.
The withdrawal of air from a room
by an exhaust system creates vacuum
and for this reason sufficient inlets for
air shall be left open.
The main trunk lines shall be pro-
vided with suitable cleanouts not over
10 feet apart and the end of the main
trunk line shall be blanked off with a
removal cap placed on the end.
The sizes of the branch pipes lead
ing to the hoods for polishing and
grinding wheels shall be as follows:
Diameter Of
Diameter of Wheels Branch Pipe
From in. up to and including
10 ln., ........ ...... - f-ln.
More than 16 in. up to and in
cluding "a in, ......... in.
More than "a in. up to and in
cluding 30 in, .......... in.
For rag wheels the following di-
mensions shall be used:
Diameter of
Diameter of Wheels Branch Pipe
Up to and including in, -. 3 in.
more IHdn lH' up W anu IN
cludiDg II in, IN.
More than 2 in. up to and in
cluding 16 in, ........ Az in.
More than 6 in. up to and in
cluding "a in, ......... in.
More than "a in, up to and in
cluding 80 in. ......... 6 in.
PLANS for all blower installation
should be submitted to this department
in duplicate for approval before work
is commenced and it should be clearly
specified that the system is to be in.
stalled in strict accordance with the
above rules and regulations.
These plans should show the diameter
of all wheels, dimensions of all piping,
and should also show the general con-
struction of hoods to be used. These
rules and regulations as set forth above
should be complied with before the sys-
tenn will be acceptable to the Depart
ment of Labor and Industry.
Note-The above rules and regua-
tions shall not apply to Grinding Ma
chimes upon which water is used at the
point of the grinding contact, nor shall
they apply to any factory or workshop
where men are not employed continu-
ously at such wheels or belts more than
three hours in twenty-four.