Current through Register Vol. 63, No. 12, December 1, 2024
(1) Scope - These
rules apply to all grinders except:
(a)
Standards for portable, hand-held power-driven grinders are in OAR
437-004-2230, Division
4/P.
(b) Natural sandstone
wheels.
(c) Metal, wooden, cloth or
paper wheels or discs with a layer or layers of abrasive on the
surface.
(2)
Definitions.
(a) Abrasive Wheel - cutting
device made of abrasive grains held together by organic or inorganic bonds,
including diamond and reinforced wheels.
(b) Off-hand Grinding - The grinding of
anything held in the operator's hand.
(c) Portable Grinding - A grinding operation
where the grinding machine is hand held and easily moved from one place to
another.
(d) Safety Guard - An
enclosure for an abrasive wheel. It has a peripheral and two side members. Its
purpose and design is to contain the pieces of the wheel if the wheel breaks
while in use.
(3) Use.
(a) Mount grinders securely on the floor,
bench, foundation or other structure.
(b) Do not use grinders that vibrate or are
out of balance.
(c) Do not use
abrasive wheels that are out of round or out of balance.
(d) Off-hand grinding machines must have work
rests that are:
(A) Rigid and adjustable to
compensate for wheel wear.
(B) Kept
adjusted to within 1/8 inch of the wheel to prevent work from jamming between
the wheel and the rest.
(C)
Securely tightened after each adjustment.
(e) Do not adjust a moving wheel.
(f) Do side grinding only on wheels designed
for that purpose.
NOTE: Dressing on the side of straight wheels is
acceptable only with very light pressure.
(4) Mounting.
(a) Assure that grinding wheels fit freely
but not loosely on the spindle, sleeves or adapters and remain free under all
grinding conditions.
(b) Do not
operate an abrasive wheel designed to be held by flanges unless it is properly
mounted between suitable flanges. Flanges must be at least 1/3 the diameter of
the wheel, except for those types requiring flanges of a special
design.
(c) Install blotters
(compressible washers) between flanges and abrasive wheel surfaces to insure
uniform distribution of flange pressure.
(d) Properly position the safety guard after
mounting a wheel.
(e) Run the
grinder at operating speed after mounting an abrasive wheel with the safety
guard in place or in a protected enclosure for at least one minute before using
it. Keep employees away from the front of the wheel during this time.
(f) Do not use wheels larger than those
recommended by the manufacturer.
(5) Safety guards.
(a) Use abrasive wheels larger than 2 inches
in diameter only on machines with safety guards.
(b) These do not require safety guards:
(A) Specially-shaped abrasive wheels mounted
in a mandrel-type bench or floor stand and used for and commonly known as
"sickle grinding stones or wheels".
(B) Abrasive wheels where the work itself
provides full protection but only while the wheel is within the area of
protection.
NOTE: Abrasive wheel safety guards must meet the
design specifications of the American National Standard Code for the Use, Care,
and Protection of Abrasive Wheels (ANSI B7.1-1988).
(c) Abrasive wheels that cover the
spindle end, nut, and outer flange projection of the wheel must have guards.
Guard the sides and periphery of the wheel except for that degree of exposure
permitted below.
(A) Bench and floor stands.
(i) The maximum permissible angle of exposure
is 90°. Begin this exposure at a point not more than 65° above the
horizontal plane of the wheel spindle.
(ii) Do not exceed 125° exposure where
the nature of the work requires contact with the wheel below the horizontal
plane of the spindle. Begin this exposure at a point not more than 65°
above the horizontal plane of the wheel spindle.
(B) Swing frame grinders. The maximum
permissible angle of exposure is 180°. Enclose the top half of the wheel.
(C) Top grinding. Do not exceed
60° exposure of the grinding wheel periphery where the work contacts the
top of the wheel.
(d)
The peripheral protecting part of safety guards must adjust to compensate for
wheel wear when the operator stands in front of the opening.
(e) Maintain 1/4 inch between the wheel
periphery and the adjustable tongue or the guard above the
wheel.
Publications: The publication(s) referred to or incorporated
by reference in this rule are available from the
agency.
Stat. Auth.: ORS
654.025(2)
& ORS 656.726(3)
Stats. Implemented: ORS
654.001 - ORS
654.295