Harrisburg telegraph. [volume] (Harrisburg, Pa.) 1879-1948, 1915-01-01

Note: All blowers and exhausters
shall have all exposed collars, set
screws, shafts, couplings, clutches,
keys, pulleys, gears and belts guarded
as provided for by the regulations for
the transmission of power unless 9TH
er regulations have been approved by
the Industrial Board for special cases.
(a) Suction Tests.-Sufficient sue
ton 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 a U-Shaped
tube. Pressure to be taken by press
ing tube attachment over small open
ing through pipe, commonly called
Static method. Tests to be made with
all branches open and unobstructed.
(b) Piping.-Round pipe shall be
used for all main ducts and branch
connections unless some other form is
specifically approved by the Commits
sioner of Labor and Industry. All
branch pipes must enter the main
| trunk pipe at an angle of 40 degrees
or less. All bends. turns, or elbows in
such pipes must be made with easy,
smooth surfaces having a radius in
the throat of not less than two dame
| ters of the pipe on which they are
connected. No branch pipe shall eX-
| tend into the main duct and all laps
shall be made in the direction of air
| flow.
(c) Emery wheel and bufflng wheel
| exhaust systems shall be kept sepa-
rate owing to danger of sparks from
the former setting fire to the lint dust
from the latter. If both are drawn in
] to the same suction main.
| Cd The inlet of the eXhauster shall
{ be at least 30 per cent. greater in area
than the combined areas of the several
connections to the hoods, and this in
l T.. H. .s..x l.
red proportionately throughout the
entire trunk line. The piping on the
outlet of the fan is also to be at least
20 per cent. greater than the com
bined areas of the several connections
to the hoods
(e) The area of the main duct al
any point should be equal as near al
possible to the combined areas of al
branch pipes to that point, plus the
necessary 20 per cent. excess area. Ir
general not more than two branches
should be connected to a section oi
uniform diameter in the main duct
0) The use of screens across the
mouth of branch pipes is prohibited.
| (g) The withdrawal of air from 6
room by an exhaust system creates
vacuum and for this reason sufficien
Iinlets for air shall be left open.
i (h) The main trunk lines shall b'
provided with suitable clearouts no
over 10 feet apart and the end of tn,
main trunk line shall be blanked of
with a removal cap placed on tn,
end.
ID The sizes of the brancl
pipes leading to the hoods for polish
ing and grinding wheels shall be a
follows:
i DIAMETERs OF WHEELS
J Diameter o
Branch Pip,
: From inches up to and
, including 16 inches -. inches
More than 16 inches up to
and including "a inches 8 inche
More than "a inches up to
and including 80 inches 6 inche
For rag wheels the following dimen
sions shall be used:
DIAMETERS OF WHEELS
Il Diameter o
Branch Pip
Up to and including 6
: inches .............. inche
More than G inches up to
; and including Il inches inche
. More than 2 inches up to
and including 16 inches ~. inche
/ More than 16 inches up to
: and including "a inches inche
r More than "a inches up to
and including 30 inches 6 inche
Cd Plans for all blower installa
} tlons should be submitted to this de