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]