Rule 2463.
(1)
Point of operation devices shall protect the operator by 1 of the following
methods:
(a) Preventing or stopping, or both,
the normal stroking of a press if the operator's hands are inadvertently placed
in the point of operation.
(b)
Withdrawing an operator's hands if they are inadvertently located in the point
of operation as the dies close or preventing the operator from inadvertently
reaching into the point of operation as the dies close.
(c) Preventing the operator from
inadvertently reaching into the point of operation at all times.
(d) Requiring the application of both of the
operator's hands to the machine's operating controls and locating the controls
at a distance from the point of operation that will permit the slide to
complete the downward travel or stop before the operator can reach into the
point of operation with his or her hands.
(e) Enclosing the point of operation before a
press stroke can be initiated and maintaining this closed condition until the
motion of the slide ceases.
(f)
Enclosing the point of operation before a press stroke can be initiated so as
to prevent an operator from reaching into the point of operation before die
closure or before cessation of slide motion during the downward
stroke.
(2) A gate or
movable barrier device shall protect the operator according to the following:
(a) A type-A gate or movable barrier device
shall protect the operator as prescribed in subrule (1)(e) of this
rule.
(b) A type-B gate or movable
barrier device shall protect the operator as prescribed in subrule (1)(f) of
this rule.
(3) The
presence-sensing point of operation device shall protect the operator as
provided in subrule (1)(a) of this rule and shall be interlocked into the
control circuit to prevent or stop slide motion if the operator's hand or other
body part is within the sensing field of the device during the down-stroke of
the press slide. All of the following provisions apply to a presence-sensing
point of operation device:
(a) The device
shall not be used on machines that use full-revolution clutches.
(b) The device shall not be used as a
tripping means to initiate slide motion.
(c) The device shall be constructed so that a
failure within the system does not prevent the normal stopping action from
being applied to the press when required, but does prevent the initiation of a
successive stroke until the failure is corrected. The failure shall be
indicated by the system.
(d)
Bypassing the protection function of a presence-sensing device during the
upstroke of the press slide is permitted for the purpose of parts ejection,
circuit checking, and feeding.
(e)
The safety distance (Ds) from the sensing field to the point of operation shall
be greater than the distance that is determined by the following formula:
D(s) 63 inches/second X T(s)
where:
D(s) minimum safety distance (inches); 63 inches/second
= hand speed constant; and
T(s) stopping time of the press measured at
approximately 90 deg. position of crankshaft rotation (seconds).
(f) Guards shall be used to
protect all areas of entry to the point of operation that are not protected by
the presence-sensing device.
(4) The pull-out device shall protect the
operator as prescribed in subrule (1)(b) of this rule and shall include
attachments for each of the operator's hands. All of the following provisions
apply to a pull-out device:
(a) Attachments
shall be connected to, and operated only by, the press slide or upper
die.
(b) Attachments shall be
adjusted to prevent the operator from reaching into the point of operation or
to withdraw the operator's hands from the point of operation or other pinch
points before the dies close.
(c) A
separate pull-out device or other safeguarding device that is in compliance
with the provisions of this standard shall be provided for each operator if
more than 1 operator is used on a press.
(d) Each pull-out device in use shall be
visually inspected and checked for proper adjustment at the start of each
operator's shift, after a new die setup, or when operators are changed.
Necessary maintenance or repair, or both, shall be performed and completed
before the press is returned to production. The employer shall maintain records
of these inspections and the maintenance work performed.
(e) Bolts, locator pins, or any other
projections shall not be located in a manner that would catch the pullback
cable or wristlet and hold an operator's hand in a pinch point or the point of
operation.
(5) A sweep
device shall not be used for point of operation safeguarding on a mechanical
power press.
(6) A holdout or a
restraint device shall protect the operator as prescribed in subrule (1)(c) of
this rule and shall include attachments for each of the operator's hands. These
attachments shall be securely anchored and adjusted so that the operator is
restrained from reaching into the point of operation. A separate set of
restraints or other safeguarding device that is in compliance with the
provisions of this standard shall be provided for each operator if more than 1
operator is required on a press.
(7) The 2-hand control device shall protect
the operator as prescribed in subrule (1)(d) of this rule. All of the following
provisions apply to a 2-hand control device:
(a) When used in press operations requiring
more than 1 operator, separate 2-hand controls shall be provided for each
operator and shall be designed to require concurrent applications of all
operator's controls to activate the slide. The removal of a hand from any
control button shall cause the slide to stop.
(b) Each 2-hand control that is used as a
point of operation device shall be operated in the single-stroke mode
only.
(c) When hand-in-die loading
or unloading is used, the safety distance (Ds) between each 2-hand control
device and the point of operation shall be greater than the distance determined
by the formula prescribed in subrule (3)(e) of this rule.
(d) The position of the 2-hand controls shall
be established and fixed in accordance with the provisions of subrule (1)(d) of
this rule or subdivision (c) of this subrule, whichever shall apply. Only the
supervisor or safety engineer may authorize relocating the controls.
(8) The 2-hand trip device shall
protect the operator as prescribed in subrule (1)(d) of this rule. The device
shall conform as follows:
(a) When used in
press operations that require more than 1 operator, separate 2-hand trips shall
be provided for each operator and shall be designed to require concurrent
application of all operator's controls to activate the slide.
(b) Each 2-hand trip shall meet the
construction requirements of
R
408.12434.
(c) The safety distance (D(m)) between the
2-hand trip and the point of operation shall be greater than the distance
determined by the following formula:
D(m) 63 inches/second X T(m);
where:
D(m) minimum safety distance (inches); 63
inches/second=hand speed constant;
And
T(m) the maximum time the press takes for the die
closure after it has been tripped (seconds). For full revolution clutch presses
with only one engaging point T(m) is equal to the time necessary for one and
one-half revolutions of the crankshaft. For full revolution clutch presses with
more than one engaging point, T(m) shall be calculated as follows:
T(m) [1/2 + (1 divided by number of engaging points per
revolution)] X time necessary to complete one revolution of the crankshaft
(seconds).
(d) Two-hand
trips shall be established and fixed and only a supervisor or safety engineer
may authorize their relocation.