a.
General requirements.
(1) [Reserved]
(2) [Reserved]
(3) Auxiliary equipment. Mechanical and
electrical equipment and auxiliaries shall be installed in accordance
with this section and Subpart S of this part.
(4) Mill roll heights. All new mill installations
shall be installed so that the top of the operating rolls is not less
than 50 inches above the level on which the operator stands, irrespective
of the size of the mill. This distance shall apply to the actual working
level, whether it be at the general floor level, in a pit, or on a
platform.
(b)
Mill safety controls -
(1) Safety trip control. A safety trip
control shall be provided in front and in back of each mill. It shall
be accessible and shall operate readily on contact. The safety trip
control shall be one of the following types or a combination thereof:
(i)
Pressure-sensitive body bars. Installed at front and back of each
mill having a 46-inch roll height or over. These bars shall operate
readily by pressure of the mill operator's body.
(ii) Safety triprod. Installed in the front and in the back of each
mill and located within 2 inches of a vertical plane tangent to
the front and rear rolls. The top rods shall be not more than 72
inches above the level on which the operator stands. The triprods
shall be accessible and shall operate readily whether the rods are
pushed or pulled.
(iii) Safety tripwire cable or wire center cord. Installed in the
front and in the back of each mill and located within 2 inches of
a vertical plane tangent to the front and rear rolls. The cables
shall not be more than 72 inches above the level on which the operator
stands. The tripwire cable or wire center cord shall operate readily
whether cable or cord is pushed or pulled.
(2) [Reserved]
(3) Auxiliary equipment. All auxiliary equipment
such as mill divider, support bars, spray pipes, feed conveyors, strip
knives, etc., shall be located in such a manner as to avoid interference
with access to and operation of safety devices.
(c)
Calender safety controls -
(1) Safety trip, face. A safety triprod,
cable, or wire center cord shall be provided across each pair of in-running
rolls extending the length of the face of the rolls. It shall be readily
accessible and operate whether pushed or pulled. The safety tripping
devices shall be located within reach of the operator and the bite.
(2) Safety trip, side. On both sides of
the calender and near each end of the face of the roll, there shall
be a cable or wire center cord connected to the safety trip. They
shall operate readily when pushed or pulled.
(d)
Protection by location -
(1)
Mills. Where a mill is so installed that
persons cannot normally reach through, over, under, or around to come
in contact with the roll bite or be caught between a roll and an adjacent
object, then, provided such elements are made a fixed part of a mill,
safety control devices listed in paragraph (b) of this section shall
not apply.
(2)
Calenders.
Where a calender is so installed that persons cannot normally reach
through, over, under, or around to come in contact with the roll bite
or be caught between a roll and an adjacent object, then, provided
such elements are made a fixed part of a calender, safety control
devices listed in paragraph (c) of this section shall not apply.
(e)
Trip and emergency switches. All trip and emergency
switches shall not be of the automatically resetting type, but shall
require manual resetting.
(f)
Stopping limits -
(1)
Determination of distance of travel. All
measurements on mills and calenders shall be taken with the rolls
running empty at maximum operating speed. Stopping distances shall
be expressed in inches of surface travel of the roll from the instant
the emergency stopping device is actuated.
(2)
Stopping limits for mills. All mills irrespective
of the size of the rolls or their arrangement (individually or group-driven)
shall be stopped within a distance, as measured in inches of surface
travel, not greater than 1 1/2 percent of the peripheral no-load surface
speeds of the respective rolls as determined in feet per minute.
(3)
Stopping limits for calenders.
(i)
All calenders, irrespective of size of the rolls or their configuration,
shall be stopped within a distance, as measured in inches of surface
travel, not greater than 1 3/4 percent of the peripheral no-load
surface speeds of the respective calender rolls as determined in
feet per minute.
(ii)
Where
speeds above 250 feet per minute as measured on the surface of the
drive roll are used, stopping distances of more than 1 3/4 percent
are permissible. Such stopping distances shall be subject to engineering
determination.
[39
FR 23502, June 27, 1974, as amended at 49 FR 5323, Feb. 10, 1984;
61 FR 9227, March 7, 1996]
