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U. S. DEPARTMENT OF LABOR

JAMES J. DAVIS, Secretary
BUREAU OF LABOR STATISTICS
ETHELBERT STEWART, Commissioner
BULLETIN OF THE UNITED STATES >
B U R EAU OF LABOR S T A T IS T IC S ) • • • •

SAFETY

CODE

No. 338

SERIES

SAFETY CODE FOR THE
USE, CARE, AND PROTECTION
OF ABRASIVE WHEELS
INTERNATIONAL ASSOCIATION OF INDUSTRIAL ACCIDENT
BOARDS AND COMMISSIONS AND GRINDING WHEEL
MANUFACTURERS ASSOCIATION, SPONSORS




TENTATIVE AMERICAN STANDARD
Approved February 11, 1922, by
American Engineering Standards Committee

APRIL, 1923
WASHINGTON
GOVERNMENT PRINTING OFFICE
1923




CONTENTS.
Introduction.........................
Section I. Scope and definitions................................................................................
Rule 10. Scope......................................................................................................
11. Definitions.............................................................................................
Section II. Types of protection devices.........„........................................................
Rule 20. General requirements...........................................................................
Section III. Storage and inspection of wheels........................................................
Rule 30. Storage.................................................................................................. .
31. Inspection..............................................................................................
Section IV. General machine requirements.............................................................
Rule 40. Rigidity, supports................................................................................
41. Size of spindle.......................................................................................
42. Limit stop...............................................................................................
44. Direction of spindle thread.................................................................
45. Length of spindle thread.....................................................................
46. Size of wheel holes................................................................................
Section V. Protection hoods........................................................................................
Rule 50. General requirements.........................................................................
51. Mounting and fastenings....................................................................
52. Exposure: Bench and floor stands....................................................
53. Exposure: Cylindrical grindery........................................................
54. Exposure: Surface grinders...............................................................
55. Exposure: Swing frame and portable grinders...............................
56. Exposure: Top grinding....................................................................
57. Exposure adjustment.........................................................................
58. Fixed members....................................................................................
59. Inclosure requirements................ .*...................................................
500. Dimensions for peripheral and sidemembers..................................
501. Material specifications.......................................................................
502. Construction guide..............................................................................
503. Connection requirements..................................................................
504. Connecting members (specifications)...............................................
505. Dust exhaust provision......................................................................
Section VI. Work rests................................................................................................
Rule 60. Construction...........................................................................................
61. Adjustment........................................... ..........-...................................
Section VII., Protection for cup, cylinder, and sectional ring wheels.................
Rule 70. General requirements..........................................................................
71. Hoods......................................................................................................
72. Chucks....................................................................................................
73. Bands......................................................................................................
Section VIII. Flanges..................................................................................................
Rule 80. General requirements..........................................................................
81. Material..................................................................................................
82. Finish and balance...............................................................................
83. Uniformity of diameter........................................................................
84. Recess.....................................................................................................
85. F it...........................................................................................................
86. Straight flange dimensions..................................................................
87. Protection flange requirements..........................................................
88. Degree of taper......................................................................................
89. Tapered flange dimensions.................................................................
Section IX. Mounting..................................................................................................
Rule 90. Inspection.............................................................................................
91. F it...........................................................................................................
92. Surface condition..................................................................................
93. Bushing..................................................................................................
94. Washers...................................................................................................
95. Tightening of nut..................................................................................
hi



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3,4
3
3,4
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5,6
5
5
5
5
6
6
6-12
6
6
6
6
6
7
7
7
7
7
8
9
9-11
11
11,12
12
12
12
12
13
13
13
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13-16
13
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14
14
14
14
14
15
15
15,16
16
16
16
16
16
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16

IV

CONTENTS.

Page.

Section X. Speed........................................................................................................... 17,18
Rule 100. Recommended and maximum speeds.............................................
17
101. Peripheral speed converted, to revolutions per minute................. 17
102. Speed test............................................................................................. 18
103. Speed adjustment control.................................................................. 18
Section XI. Operating rulesand general data..........................................................
18
Rule 110. Responsibility...................................................................................... 18
111. Inspection after breakage.................................................................. 18
112. Replacing hood.................................................................................... 18
113. Starting new wheels............................................................................ 18
114. Applying work..................................................................................... 18
115. Test for balance................................................................................... 18
116. Truing................................................................................................... 18
18
117. Wet grinding...............
118. Side grinding........................................................................................ 18
119. Dresser guards...................................................................................... 18
1100. Grinding room...................................................................................... 18
1102. Lubrication.......................................................................................... 18




BULLETIN OF THE

U. S. BUREAU OF LABOR STATISTICS
WASHINGTON

no . 338

april , 1923

SAFETY CODE FOR THE USE, CARE, AND PROTEC­
TION OF ABRASIVE WHEELS.
INTRODUCTION.
On April 3, 1920, the American Engineering Standards Committee
invited the International Association of Industrial Accident Boards
and Commissions and the Grinding Wheel Manufacturers Associa­
tion of the United States and Canada to act as joint sponsors for a
safety code for the use, care, and protection of abrasive wheels.
These associations both accepted this sponsorship, and according
to the rules of procedure of the American Engineering Standards
Committee they jointly appointed a sectional committee to draft
such a code.
This sectional committee consists of the following members:
Name and address.
Chairman, L. W. Chaney, U. S. Bureau
of Labor Statistics, Washington, D. C.
H. L. Whittemore, U. S. Bureau of
Standards, Washington, I). C.
Prof. E. A. Winslow, consulting hygien­
ist, 62 Park Street, New Haven, Conn.
Fred G. Lange, Director of Safety In­
dustrial Commission of Ohio, Colum­
bus, Ohio.
R. McA. Keown, Engineer, Industrial
Commission of Wisconsin, Madison,
Wis.
John P. Meade, director, division of in­
dustrial safety, Department of Labor
and Industry, Boston, Mass.
Rowland H. Leveridge, bureau of elec­
trical and mechanical equipment. De­
partment of Labor, Trenton, N. J.
J. C. Cronin, Department of Labor and
Industry, Harrisburg, Pa.
Secretary, A. Rousseau, safety engineer,
Norton Co., Worcester, Mass.
F. R. Henry, Dayton Grinding Wheel
Co., Dayton, Ohio.
George W. Chormann, Carborundum
Co., Niagara Falls, N. Y.
John R. Kempf, Detroit Star Grinding
Wheel Co., Detroit, Mich.
J. B. Baker, Safety Emery Wheel Co.,
Springfield, Ohio.
J. H. Byers Abrasive Co., Philadelphia,
Pa.
H. W. Dunbar, member, A. S. M. E.,
Norton Co., Worcester, Mass.




Association, society, or firm
represented.

Sectional committee group.

U. S. Department of Labor......... Governmental bodies.
U. S. Bureau of Standards..........
Do.
U. S. Public Health Service........
Do.
I. A. I. A. B. C. and Industrial
Do.
Commission of Ohio.
I. A. I. A. B. C. and Industrial
Do.
Commission of Wisconsin.
I. A. I- A. B. C. and Depart­
Do.
ment of Labor and Industry of
Massachusetts.
I. A. I. A. B. C. and Depart­
Do.
ment of Labor, New Jersey.
I. A. I. A. B. C. and Depart­
Do.
ment of Labor and Industry,
Pennsylvania.
Grinding Wheel Manufacturers Manufacturers of apparatus
Association and Norton Co.
concerned (grinding wheels
and grinding machines).
Grinding Wheel Manufacturers
Do.
Association and Dayton
Grinding Wheel Co.
Grinding Wheel Manufacturers
Do.
Association and Carborundum
Co.
Grinding Wheel Manufacturers
Do.
Association and Detroit Star
Grinding Wheel Co.
Grinding Wheel Manufacturers
Do.
Association and Safety Emery
Wheel Co.
Grinding Wheel Manufacturers
Do.
Association and Abrasive Co.
National Machine Tool Builders
Do.
Association.

1

2

USE, CARE, AND PROTECTION OF ABRASIVE WHEELS.

Name and address.
C. HI Gale, superintendent foundries,
Pressed Steel Car Co., McKees Rocks,
Pa.
G. E. Sanford, member A. I. E. E ., A.
S. S.JE.and A. S.M .E ., General Elec­
tric Co., West Lynn, Mass.
Gregory Brown, Norton Co., Worcester,
F. M. Ward, Otis Elevator Co., Yonkers,
N. Y.
H. J. Weeks, chairman, General Stand­
ards Commission for State of Ohio,
American Steel and Wire Co., Pitts­
burgh, Pa.
B. C. Christy, International Harvester
Co., Chicago, 111.
S. E . Whiting.member, A. I. E . E ., Lib­
erty Mutual Insurance Co., Boston,
Mass.
L. L. Hall, Workmen’s Compensation
Service Bureau, 13 Park Row, New
York, N. Y.
F. M. Rosseland, National Safety Coun­
cil. Chicago, 111.
W. B. Gardiner, mechanical superin­
tendent, Lincoln Twist Drill Co.,
Taunton, Mass.
A. J. Gifford, Leland-Gifford Co., Wor­
cester, Mass.
G. E . Sanford, General Electric Co.,West
Lynn, Mass.
Rowland H . Leveridge, Department of
Labor, Trenton, N. J.
P . J. Conlon, 9th Street and Mt. Vernon
Place NW ., Washington, D. C.
George J. Speidel, 90 Bayway, Eliza­
beth, N. J.

Association, society, or firm
represented.

Sectional committee group.

American Foundrymen’s Asso­ Employers as users of grind­
ciation.
ing wheels.
National Founders’ Association..
Do.
National Metal Trades Associa­
tion.
Otis Elevator Co...........................
American Steel and Wire C o....
International Harvester Co.........
National Association Mutual
Casualty Co. and Liberty
Mutual Insurance Co.
National Workmen’s Compen­
sation Service Bureau.
National Safety Council...............
American Society Mechanical
Engineers.
Society of Automotive Engi­
neers.
American Society of Safety En­
gineers.
...d o ..............................................
International Association of Ma­
chinists.
Metal Polishers, Buffers and
Platers of North America.

Do.
Do.
Do.
Insurance interests.
General interests.
Engineering and technical
bodies.
Do.
Employees as users of equip
ment.
Do.

Meetings of this committee were held, and as a result a code was
drafted which was submitted first to the grinding-wheel manufac­
turers for approval. A few changes were suggested which were
resubmitted to the sectional committee and to the International
Association of Industrial Accident Boards and Commissions.
This code in its present form is the net result of this work and was
approved by the:
International Association of Industrial Accident Boards and Com­
missions executive committee, November 18, 1921.
Grinding Wheel Manufacturers Association, December 9, 1921.
Sectional committee, by letter ballot, January 30, 1922.
American Engineering Standards Committee, February 11, 1922.
The membership of the two associations sponsoring this code is as
follows:
G r in d in g W h e e l M a n u f a c t u r e r s

The Abrasive Co., Philadelphia, Pa.
American Emery Wheel Works, Provi­
dence, It. I.
Bridgeport Safety Emery Wheel Co.,
Bridgeport, Conn.
Canadian-Hart Products Co., Hamilton,
Ontario, Canada.
Carborundum Co., Niagara Falls, N. Y.
Chicago Wheel & Manufacturing Co.,
Chicago, 111.
Cortland Grinding Wheels Corporation,
Chester, Mass., and Cortland, N. Y.
Dalton Grinding Wheel Co., Dayton,



of

U n it e d S t a t e s

and

Ca n a d a .

Detroit-Star Grinding Wheel Co., Detroit,
Mich.
Dominion Abrasive Wheel Co. (Ltd.),
New Toronto, Ontario, Canada.
General Grinding Wheel Corporation,
Philadelphia, Pa.
Hampden Corundum Wheel Co., Springfield, Mass.
Norton Co., Worcester, Mass.
Norton Co. of Canada (Ltd.), Hamilton,
Ontario, Canada.
Pittsburg Grinding Wheel Co., Rochester,
Pa.

USE, CARE, AND PROTECTION OF ABRASIVE WHEELS.

G r in d in g W h e e l M a n u f a c t u r e r s

of

U n it e d S t a t e s

Precision Grinding Wheel Co., Phila­
delphia, Pa.
Safety Emery Wheel Co., Springfield,
Ohio.
Sterling Grinding Wheel Co., Tiffin,
Ohio.
Superior Corundum Wheel Co., Walt­
ham, Mass.

and

C a n a d a —Concluded.

Vitrified Wheel Co., Westfield, Mass.
Waltham Grinding Wheel Co., Waltham,
Mass.
Waltham Grinding Wheel Co. of Canada
(Ltd.), Brantford, Ontario, Canada.
White Heat Products Co., Frazer, Pa.

I n t e r n a t io n a l A sso c ia t io n of I n d u s t r ia l A c c id en t B o a r d s
C o m m issio n s .
ac tive m e m b e r s .

U. S. Employees’ Compensation Com­
mission.
U. S. Bureau of Labor Statistics.
California Industrial Accident Commis­
sion.
Connecticut Workmen’s Compensation
Commission.
Delaware Industrial Accident Board.
Georgia Industrial Commission.
Hawaii Industrial Accident Boards (coun­
ties of Kauai, Maui, Hawaii, and Hono­
lulu).
Illinois Industrial Commission.
Iowa Workmen’s Compensation Service.
Kansas Court of Industrial Relations.
Maine Industrial Accident Commission.
Maryland State Industrial Accident
Commission.
Massachusetts Industrial Accident Board.
Michigan Department of Labor and
Industry.
Minnesota Industrial Commission.
Montana Industrial Accident Board.
Nevada Industrial Commission.
New Jersey Department of Labor.
New York State Industrial Commission.
Ohio Industrial Commission.
Oklahoma Industrial Commission.
Oregon State Industrial Accident Com­
mission.
Pennsylvania Department of Labor and
Industry.

3

and

Utah Industrial Commission.
Virginia Industrial Commission.
Washington Department of Labor and
Industries.
West Virginia State compensation com­
missioner.
Wisconsin Industrial Commission.
Wyoming Workmen’s Compensation De­
partment.
Department of Labor of Canada.
Alberta Workmen’s Compensation Board.
Manitoba Workmen’s Compensation
Board.
New Brunswick Workmen’s Compensa­
tion Board.
Nova Scotia Workmen’s Compensation
Board.
Ontario Workmen’s Compensation Board.
a sso c ia t e m e m b e r s .

Idaho Industrial Accident Board.
North Dakota Workmen’s Compensation
Board.
Ontario Safety League.
Porto Rico Workmen’s Relief Commis­
sion.
Republic Iron & Steel Company, Youngs­
town, Ohio.
Industrial Accident Prevention Associa­
tion of Toronto.
Nebraska Industrial Commission.

SECTION I. SCOPE AND DEFINITIONS.
10. Scope.—This code is intended to give rules and specifications
which are necessary to insure safety in the use of abrasive wheels
operating at speeds in excess of 2,000 surface feet per minute.
11. Definitions.
S h a l l a n d s h o u l d .—The word “ shall” where used is to be under­
stood as mandatory and “ should” as advisory.
A b r a s i v e w h e e l .—The term “ abrasive wheel” where used shall be
understood to mean power-driven wheels which consist of abrasive
particles held together by artificial or natural mineral or organic
bonds. Metal, wooden, cloth, or paper wheels or discs having a
layer or layers of abrasive on the surface are not included.




4

USE, CARE, AND PROTECTION OF ABRASIVE WHEELS.

P r o t e c t i o n h o o d . —A “ protection hood” is an inclosure consisting
of a peripheral and two side members, constructed according to
specifications which appear later in this code.
C a s t h o o d .—A cast hood shall be defined as a hood which has the
peripheral protecting member cast integral with at least one side
member, and may be made of gray iron castings, malleable iron
castings, or steel castings.
F a b r i c a t e d h o o d . —A fabricated hood shall be defined as a hood
which is built up or constructed by bolting, pinning, riveting, or
welding the peripheral protecting member to the side members,
and may be made of structural steel plate, wrought-iron plate, or
an assembly of either of these in combination with gray iron castings,
malleable iron castings, or steel castings or a material possessing an
equivalent tensile strength.
P r o t e c t i o n f l a n g e s . —“Protection flanges” are flanges designed to
be used with abrasive wheels of special shape, in such a manner
as to effectively retain the parts of a wheel—should such wheel
break in operation—in addition to the usual function of clamping
the wheel to the spindle.
Protection flanges are of several types, of which the following are
the most commonly used:
“ Tapered flanges,” sometimes called safety, beveled, or concave
flanges, which are used with wheels having convex side or sides.
“ Hub flanges,” which are used with wheels having a raised hub
or hubs.
“ Ring flanges,” having concentric ring or rings projecting from
the bearing sides of the flanges, which fit into corresponding grooves
in the sides of the wheels.
P r o t e c t i o n b a n d . —A “ protection band ” is a continuous band placed
around a cup, cylinder, or sectional ring wheel to effectually retain
the pieces of such a wheel which might break in operation.
P r o t e c t i o n c h u c T c . —A “ protection chuck ” is a chuck used for mount­
ing cup, cylinder, or sectional ring wheels, so designed that the jaws
inclose the wheel up to the point specified in rule 70.
SECTION II. TYPES OF PROTECTION DEVICES.
20. General requirements.—All abrasive wheels shall be provided
with one of the following forms of protection, which are listed in the
order of preference:
( a ) Protection hoods.
(b ) Protection flanges.
(c ) Protection bands.
( d ) Protection chucks.
Exception: This requirement shall not apply to wheels qsed for
internal grinding, nor to wheels 3 inches or less in diameter running
at a speed not exceeding 3,000 feet per minute.
Forms x and d shall apply to cups, cylinders, and sectional ring
wheels; forms a and b to all other shapes of wheels.




USE, CARE, AND PROTECTION OE ABRASIVE WHEELS.

5

SECTION in. HANDLING AND STORAGE.
30. Storage.—Extreme care should be exercised in the storage of
wheels. They should be stored in dry places and should be supported
on edge in racks. Straight-sided shellac and rubber-bondea wheels
of one-fourth inch or less in thickness shall be laid flat on a straight
surface to prevent warpage.
31. Inspection.—Immediately upon receipt, all wheels should be
closely inspected to make sure that they have not been injured in
transit or otherwise. For added precaution wheels should be tapped
gently with a light implement, such as the handle of a screw driver.
If they sound cracked, they should not be used. Wheels must be
dry, and free from sawdust, when applying the test.
SECTION IV. GENERAL MACHINE REQUIREMENTS.
40. Rigidity, supports.—Grinding machines should be sufficiently
heavy and rigid so as to minimize vibration. They should be securely
mounted on substantial floors, benches, foundations, or other struc­
tures.
41. Size of spindle.—No user of wheels shall operate on any machine
of given spindle diameter a wheel of larger diameter or greater thick­
ness than specified in the following table:
Thickness of wheel in inches.

Diameter in

inches.

6...........................
7...........................
8...........................
9...........................
10.........................
12.........................
14.........................
16.........................
18.........................
20.........................
24.........................
26.........................
30.........................
36.........................

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5

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iy
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i X iy iy iy iy i y i y i y i y m m W s 2W s
iy i y i y i y i y i y i y v y i y 2 2 2 2
i y iy i y i y i y 1H 2 2 2 2 2y 2M 2 «
i y i y 2 2 2 2 2 2M 2M 2 y m 2y
2 2M 2M 2y
zy %y2M 2 y 3 3

42. Limit stop.—Grinding machines should be provided with a
stop or other means of fixing the maximum size of wheel which can
be used.
44. Direction of spindle thread.—Ends of spindles shall be so
threaded that the nuts on both ends will tend to tighten as the spindles
revolve. Care should be taken in setting up machines that the
spindles are arranged to revolve in the proper direction, else the nuts
on the ends will loosen.
N ote .—To remove the nuts they should both be turned in the direction that the
spindle revolves when the wheel is in operation.
37543°—23—Bull. 338-----2




6

USE, CAKE, AND PROTECTION OF ABRASIVE WHEELS.

45. Length of spindle thread.—The length of the spindle and the
distance from the end which the thread extends shall be such as to
allow the entire length of the nut to bear on the thread so as to exert
its full pressure on all thicknesses of wheels which may be used.
46. Size of wheel holes.—Wheel holes should be made approxi­
mately 0.005 inch large.
SECTION V. PROTECTION HOODS.
50. General requirements.—Hoods should be used on every opera­
tion where the nature of the work will permit, and shall always be
used with wheels which are not provided with protection flanges,
chucks, or bands.
51. Mounting and fastenings.—Hoods shall be so mounted as to
maintain proper alignment with wheels, and the fastenings shall have
ample strength to minimize displacement in case of wheel breakage.
52. Exposure: Bench and floor stands.—
The maximum angular exposure of the
grinding wheel periphery and sides for
hoods used on machines known as bench
and floor stands should not exceed 90 or
one-fourth of th e
periphery. This ex­
posure snail begin at
a p o in t n o t more
than 65° above the
F /£ /
horizontal plane of
the wheel spindle. (See fig. 1.)
Wherever the nature of the work requires
contact with the wheel below the horizontal
plane of the spindle, the exposure shall not
F /G .&
exceed 125°. This exposure shall begin at a
point.not more than 65° above and extend to a point not more than
60° below the horizontal plane of the wheel spindle. (See fig. 2.)
53. Exposure: Cylindrical grinders.—The
maximum angular exposure of the grinding
wheel periphery and sides for hoods used on
cylindrical grinding ma­
chines shall not exceed
180°. This exposure
shall begin at a point
not more than 65° above
the horizontal plane of
*°°&ore
the wheel spindle. (See
F /& .3
fig. 3.)
54. Exposure: Surface grinders.—The maximnm angular exposure of the grinding wheel
F /& 4
periphery and sides for hoods used on surface grinding machines
which employ the wheel periphery shall not exceed 150°. (See
fig. 4.)




USE, CARE, AND PROTECTION OE ABRASIVE WHEELS.

7

55. Exposure: Swing frame and portable
grinders.—The maximum angular exposure of
the grinding wheel periphery and sides for
hoods used on machines known as swing frame
and portable grinding machines shall not ex­
ceed 180°, and the top
,
half of the wheel shall
be protected at all
times. (See fig. 5.)
56. Exposure: Top grinding.—In operations
where the work is ground on the top of the
wheel, the exposure of the grinding wheel pe­
riphery shall be as small as practicable, with a
maximum exposure of 60°. (See fig. 6.)
57. Exposure adjustment.—Hoods shall be
/^ /s .e
constructed so that the peripheral protecting
member can be adjusted to the constantly decreasing diameter of the
wheel by means of an adjustable tongue, or its equivalent, so that
the angular protection specified in rules 52 to 56 will be maintained
througnout the life of the wheel, and the maximum distance between
the wheel periphery and tongue or end of peripheral band at top of
opening will not exceed inch. (See figs. 7, 8, and 9.)

E /G . 8 - C O R R E C T .
Showing adjustoh/e ton gi/e
giving reg t/iret/o n g o /o r
p rotection fo r a //s iz e s
o f wheeis ucect.

Showing m ovoh/e hooct
with opening sm o /i enough £>
give regoiredprotection fo r
sm oi/est size w h ee/ u sed

E /G . 9 -IN C O R R E C T .
Showing m ovch/e t?ooctw it/?
size o f opening correct for
fu itsize w hee/, h u t too
iorge fo r sm o //e r w heeif.

58. Fixed members.—Hoods shall be constructed so that it is not
necessary when changing wheels to detach the peripheral protecting
member from the side member which is connected to the machine.
59. Enclosure requirements.—The hood shall inclose the spindle end,
nut, and flange projections, if any.

N
.—Protection hoods on cylindrical grinding machines, in all operations where
the work provides a suitable measure of protection to the operator, may be so con­
structed that the spindle end, nut, and flanges are exposed; and where the nature of
the work is such as to entirely cover the side of the wheel, the side covers of the guard
may be omitted.
ote




8

USE, CAKE, AND PROTECTION OF ABRASIVE WHEELS.

500. Minimum dimensions for the peripheral and side members.




9

USE, CAKE, AND PROTECTION OF ABRASIVE WHEELS.

501. Material specifications.—Materials used in the construction
of hoods shall conform to and be in accordance with the following des­
ignated specifications of the American Society for Testing Materials:
( a ) Gray-iron castings—A 48.
( b ) Malleable-iron castings—A 47.
( c ) Steel castings—A 27 (class A).
( d ) Structural steel plate—A 9 (excluding specifications for rivet
steel).
( e ) Wrought-iron plate—A 42 (class A).

N o t e .—Copies of these specifications may be procured at a nominal price from the
American Society for Testing Materials, Philadelphia, Pa.

502. Construction guide.—As a guide for the construction of
fabricated hoods of steel plate or wrought iron the following drawings
have been prepared. Other types offering equal protection will also
be accepted.
The requirements given in columns C, D, and E of this table shall
apply also to cast hoods; and in such cases where the tongue is held
by bolts, column F shall also apply.
C
Maximums^ace
Diameter of tween
wheel in
new
inches.
wheel
and
hood
at pe­
riphery
in
inches.

Under 12.. i x
12 to 1 6 ... IX
17 to 24 . . .
Over 24__ iIX
x




D

E

Maximum inside
width of hood.

Length
of
tongue
in
inches.

1 A inches wider

3X
• than wheel.
2 inches wider 5
than wheel.
........do.................... 6
........do.................... 7

F

G

Diam­
eter of
bolts Size of angle supports
for
for tongue and rest
tongue in inches.
in
inches.

by V/2 by J^..
a 2 by 2 by
A 2 by 2 by y . .
X VA by 2A by y . .
X

H

J

Diam­
eter of
rivets
for sup­
ports
in
inches.

Diam­
eter of
end
con­
necting
bolts
in
inches.

A

A

X

X

x

A

A

X

10

USE, CARE, AND PROTECTION OF ABRASIVE WHEELS,




F IG -.

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F IG . fZ

USE, CARE, AND PROTECTION OF ABRASIVE WHEELS,

Z

11

Position opftonaf

I lT

Ac/jujfab/e Torque

NOTE:
D u s t e x h a u s t outlet should
b e located In the p o s itio n
where i t w ill most e ffe c tiv e ly
remove the dust.

For Suction Pipe sizes
«see Pu/e SO S .

F ig . 13.
F R O N T V IEW ,A LS O C R O S S S E C T I O N S S H O W I N G F O U R
S A T I S F A C T O R Y M E T H O D S OF SEC U R IN G C O Y E R ^ B S

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e q u a l a r e a o t p e r ip h e r a l

S EC T IO N
tN T Q

SH O W IN G

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ON

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ENDS

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Or

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COVER
FLA T

SECTIO N
IN TO
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IN TO
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W EDGE

SH O W IN G

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THROUGH

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THREADED

O N LY - C O V E R

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IR O N

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STUO THREADED

O N L Y - C O ^ £ ff H E L D

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OF

STUD S

F IG

.

14-

P P O N T VICW

503. Connection requirements.—Hoods shall be constructed so that
the connections between the peripheral and side members, or be­
tween parts of a sectional hood, will have a strength in a radial direc­
tion at least equal to the strength of the material of which the hoods
are constructed.
504. Connecting members (specifications).



12

USE, CARE, AND PROTECTION OF ABRASIVE WHEELS.

MINIMUM SIZES AND SPACING OF RIVETS, BOLTS, AND STUDS FOR CONNECTING
PERIPHERAL AND SIDE MEMBERS IN FABRICATED HOODS OF WROUGHT-IRON
AND STEEL PLATE.
For side plate (B -l) at­
tached to machine.

For detachable side plate
(B-2).

Thickness of plates
being connected
Maximum Diameter Maximum
in inches.
Diameter distance
be­ of bolts or distance be­
of rivets tween centers
tween centers
in inches. in inches. in studs
inches. in inches.

Y and A .......
A and A......
A and {A .....
AY and
and A......
y s .......
M and A .......
Vi and J*.......

A and A.....
A and .......
Vs and .......

% and A .......

A and M.......
AY and
A .......
and A .......

Y and % .......

V% and
U and A .......

AAA
Aa

H
H

Vs
Vs
Vs
Vs
Vs
Vs
Vs
Vs
Vs
Vs

m
iy 2
m

2

1%

2
2
2
iH
m
VY
W2

A
A
AVs
A

Vs
Vs

A
A
AA
A
AA
A
%

3
3
3
3

4

SY

3

4
4
4

3Y

3
3
3
3
3
3

505. Dust-exhaust provision.—Hoods on machines used for dry
grinding and other operations where dust is produced shall have
provision made for connection to an exhaust system.
The size of such connections shall be in conformity with the follow­
ing specified dimensions:
Medium diameter
Diameter of wheel.

of branch pipe.

6 inches or less in diameter............................................................3 inches.
7 to 16 inches in diameter............................................................... 4 inches.
17 to 24 inches in diameter............................................................. 5 inches.
25 to 30 inches in diameter............................................................. 6 inches.

A modification of the above requirements will be allowed in the case
of narrow wheels used for light work where very little dust is generated
and where a smaller pipe will satisfactorily remove it.
The requirements m this paragraph shall not apply to swing-frame
and portable grinding machines.
SECTION VI. WORK RESTS.
60. Construction.—Work rests shall be rigid in construction.
61. Adjustment.—The work rest should be kept adjusted close to
the wheel, with a maximum distance of Y inch, to prevent the work
from being caught between the wheel and rest, and should be securely
clamped after each adjustment.




USE, CARE, AND PROTECTION OE ABRASIVE WHEELS.

13

SECTION VII. PROTECTION FOR CUP, CYLINDER, AND
SECTIONAL RING WHEELS.
70. General requirements.—Cups, cylinders, and sectional ring
wheels shall be either protected with hoods, inclosed in protection
chucks, or surrounded with protection bands. Not more than onequarter of the height of such grinding wheels shall protrude beyond
the provided protection. Where the thickness of the rim of such
wheels is less than 2 inches, the maximum distance which the wheel
may protrude beyond the provided protection shall not exceed 1
inch. If the thickness of the rim is 2 inches or more, the wheel m aj
protrude 2 inches beyond the protection, but shall not exceed this
amount.
71. Hoods.—Where hoods are used they shall conform to the specifi­
cations given in rules 50 to 505, inclusive, in this code.
72. Chucks.—Where the chuck which holds the wheel is the only
protection provided, it shall be so designed that the jaws will at all
times protect the wheel up to the point specified in rule 70.
73. Bands.—Where protection bands are used, they shall conform
to the following specifications:
( a ) They shall be made of wrought-iron or steel plate or other
material oi equal strength, shall be continuous and bent to conform
as closely to tne periphery of the wheel as practical. The ends shall
either be riveted, bolted, or welded together in such a manner as to
leave the inside of the band free from projections.
(b ) The bands shall be of sufficient width to provide the protection
specified in rule 70.
(c ) The thickness of the band shall be made according to the
following table, which also shows the size and spacing for riveted
joints. If bolting or welding is used, the strength of the connections
shall be at least equal to the riveted joints specified in this table.
MINIMUM THICKNESS, SIZE. AND SPACING OF RIVETS FOR PROTECTION BANDS FOR
CUPS, CYLINDERS, AND SECTIONAL RING WHEELS.
Size of wheels in inches.

Under 8...............................
8 to 24.................................
25 to 30...............................

Thickness Mirnmnmof
of band in diameter
rivets in
inches.
inches.

A
X
X

A
X
X

Maximum

distance
between
centers in
inches.

iX
IX

i
SECTION VHI. FLANGES.
80. General requirements.—All wheels excepting those which are
mounted in chucks shall always be run with flanges.
81. Material.—All tapered flanges over 10 inches in diameter shall
be of steel, or other material of equal strength. All other flanges
may be made of cast iron, or other material of equal strength.




14

USE, CARE, AND PROTECTION OF ABRASIVE WHEELS.

82. Finish and balance.—Flanges shall be finished all over correct
to dimensions and in balance. The requirement for balance does not
apply to so-called balancing flanges, which are purposely made out of
balance.
83. Uniformity of diameter.—Both flanges, whether straight or
tapered, in contact with wheel, shall be of the same diameter.
84. Recess.—Each flange, whether straight or tapered, shall be
recessed at the center at least one-sixteenth of an inch on the side
next to the wheel for a distance as specified in the respective tables
of dimensions for straight and tapered flanges.
85. Fit.—The inner flange shall be keyed, screwed, shrunk, or
pressed onto the spindle, and the bearing surface shall run true and
at right angles with the spindle. The bore in the outer flange should
be not more than 0.002 inch larger than the spindle.
86. Straight flange dimensions.—Where protection hoods are used,
sizes of straight flanges for straight wheels shall not be less than shown
in the following table:

[All dimensions in inches.]
A
Diameter
of wheel
in inches.

1
2
3
4
5

6
8
10
12

14
16
18
20
22

24
26
28
30

36




c

B
Minimum
outside
diameter
of flanges.

l

Minimum. Maximum.

Vs
X
Vs
Vs

A

H
H

X

A

yg

A
A

2

X
X

3
3J*
4

X

X
Vs
Vs

A
A

6

7

7A

8

10
10

*A

12

D

Radial width of
bearing surface.

1

Vs
X
X
Vs
Vs
X
X
Vs
Vs

1

u

1
in
ix
ix
ix
ix

2

E
Minimum
MioiTrmm thickness of
thickness flange at
of flange
edge of
at bore.
recess.
A

X

A
A

X
Vs
Vs
Vs
X
X
X
Vs
Vs
Vs
Vs
Vs
X
X
Vs

A
A
A

Vs
Vs

A
A

X

A
A
A

Vs
Vs

A
A

X
X
Vs
X

USE, CARE, AND PROTECTION OF ABRASIVE WHEELS.

15

87. Protection flange requirements.—Protection flanges (see defi­
nition) shall always be used with wheels 6 inches and larger which
are not provided with protection hoods, chucks, or bands. (See
rule 50.) Specifications follow for the tapered type only, which type
should be used wherever possible.
88. Degree of taper.—Tapered protection flanges (see definition)
shall always be used with tapered wheels having the same degree of
taper, which should be at least % inch per foot tor each flange.
89. Tapered flange dimensions.—Where no hoods are used, the di­
mensions of taper flanges shall not be less than shown in the follow­
ing table:




USE, CAKE, AND PROTECTION OF ABRASIVE WHEELS.

16

[All dimensions in inches.]
A
Diam­
eter of
wheel
in
inches.

6

8

10
12

14
16
18
20
22

24
26
28
30
36

c

B

D

E
F
thick­ Minimum thick­
ness of flange,
ness at edge
Maxi­
ofrecess.
at bore.
mum
flat
spot at
For
For
For
For
center
Maxi­ double single double single
of
mum. taper taper taper taper flange.
wheels. wheels. wheels. wheels.

Radial width of
bearing surface.

Mini­
mum
outside
diam­
eter of Mini­
flanges. mum.

3
4
5
6
8

14
16
18

20
22

24
28

hi

l

X

l

Vs
X

10
12

X

X

A

l

Vs

iM

W*

iX

2
23^

IX

3

Ws
ix
i%

2
2

Wi
m
m

4
4

Minimum

X

X

Vs

Vs
x
x
Vs
Vs
%

H

X

Vs
%
Vs
1
1

A

X
X

A

A

Vs
Vs
x

Ws

X

%
%

IX

Ws

A

l Vs

ix
Ws

X

X
X

m

A

X
X

A

Vs
Vs
Vs

Vs

A

A
A

Vs
Vs
a
X
Vs

1

G
Approxi­
mate
diam­
eter of
flat
spot or
hub of
wheel.

0
0
0

1
1
2

4
4
4
4
4
4
4
4
4
4
4

4^
4H
6
6
6
6
6
6
-6
6
6

N o t e .— Where hoods are used in conjunction with tapered wheels and tapered
flanges, the specifications given in rule 86 may be followed.

SECTION IX. MOUNTING.
90. Inspection.—Before mounting, all wheels should again be closely
inspected to make sure that they have not been injured in transit,
storage, or otherwise. (See rule 31.)
91. Fit.—Grinding wheels shall fit freely on the spindles; they
should not be forced on, nor should they be too loose. (See rule 46.)
92. Surface condition.—All surfaces of wheels, washers, and flanges
in contact with each other should be free from foreign material.
93. Bushing.—The soft metal bushing shall not extend beyond the
sides of the wheel.
94. Washers.—Washers or flange facings of compressible material
shall be fitted between the wheel and its flanges. If blotting paper is
used, it should not be thicker than 0.025 inch. If rubber or leather
is used, it should not be thicker than inch. If flanges with babbitt
or lead facings are used, the thickness of the babbitt or lead should
not exceed inch. The diameter of the washers shall not be smaller
than the diameter of the flanges.
95. Tightening of nut.—When tightening spindle end nuts, care
should be taken to tighten same only enough to hold the wheel
firmly; otherwise the clamping strain is liable to damage the wheel
or associated parts.




USE, CARE, AND PROTECTION OF ABRASIVE WHEELS.

17

SECTION X. SPEED.
100. Recommended and maximum speeds.—The speeds shown in
column A of the following table should not be exceeded, except on
recommendation of the wheel manufacturer, and in no case should
speeds shown in column B be exceeded.

N o t e .—Some manufacturers are willing to recommend higher speeds for precision
grinding and on rubber bonded wheels.

Wheel classification.

A
Standard
peripheral
speed
(feet per
minute).

B
Maximum
peripheral
speed
(feet per
minute).

4,500
5,000

5.500
6.500

8,000
8,000
5,000

10,000
10,000
6,500

Vitrified and silicate wheels.
Cup and cylinder wheels when used for rough grinding, on bench, floor, portable
machines, etc....................................................................................................................
All other vitrified and silicate bonded wheels...............................................................
Rubber and shellac bonded wheels.

Rubber bonded wheels......................................................................................................
Shellac bonded wheels used for cutting off..................................................................
All other shellac bonded wheels.......................................................................................

101. Table of speeds.
REVOLUTIONS PER MINUTE FOR VARIOUS SIZES OF GRINDING WHEELS TO GIVE
PERIPHERAL SPEED IN FEET PER MINUTE AS INDICATED.
Diameter of wheel in inches.
1
3

30.................. .....................................................
32........................................................................
34........................................................................
36........................................................................

4,000
s. f. m.

4,500
s. f. m.

5,000
s. f. m.

5,500
s. f. m.

6,000
s. f. m.

15,279
7,639
5,093
3,820
3,056
2,546
2,183
1,910
1,528
1,273
1,091
955
849
764
694
637
586
546
509
477
449
424

17,200
8,590
5,725
4,295
3,440
2,865
2,455
2,150
1,720
1,453
1,228
1,075
957
860
782
716
661
614
573
537
506
477

19,099
9,549
6,366
4,775
3,820
3,183
2,728
2,387
1,910
1,592
1,364
1,194
1,061
955
868
796
733
683
637
596
561
531

21,000
10,500
7,000
5,250
4,200
3,500
3,000
2,635
2,100
1,750
1,500
1,314
1,167
1,050
952
876
809
749
700
657
618
584

22,918
11,459
7,639
5,730
4,584
3,820
3,274
2,865
2,292
1,910
1,637
1,432
1,273
1,146
1,042
955
879
819
764
716
674
637

6,500
s. f. m.
24,850
12,420
8,270
6,205
4,970
4,140
3,550
3,100
2,485
2,070
1,773
1,552
1,380
1,241
1,128
1,035
955
887
827
776
730
689

N ote.—“ Centrifugal force, ” which is the force that tends to rupture a given wheel
when overspeeding, increases as the square of the velocity of that wheel. For exam­
ple, the centrifugal force in a wheel running at 5,500 surface feet per minute is 49
per cent greater than in the same wheel running at 4,500 surface feet per minute,
although the speed is actually only 22 per cent greater.




18

USE, CARE, AND PROTECTION OF ABRASIVE WHEELS.

102. Speed test.

— Machine spindle speeds shall be tested and deter­
mined correct for size of wheel to be operated, before the wheel is
mounted, and shall never be changed as wheel is reduced in diamater,
except b y men assigned for such duties.
— Where speed of wheel spindle
is adjustable, speed adjustment shall be in control of authorized
persons only.

103. Speed adjustment control.

SECTION XL OPERATING RULES AND GENERAL DATA.
110. Responsibility.— Competent men should be assigned to the
mounting, care, and inspection of grinding wheels and machines.
111. Inspection after breakage.— Whenever a wheel breaks, a
careful inspection shall be made to make sure that the hood has not
been damaged, nor the flanges bent or sprung out of true or out of
balance. The spindle and nuts shall also be carefully inspected.
— After mounting a new wheel, care should
be taken to see that the hood is properly replaced.
All new wheels shall be run at full
operating speed for at least one minute before applying work, during
which time the operator shall stand at one side.
— Work should not be forced against a cold
wheel, but applied gradually, giving the wheel an opportunity to
warm and thereby minimize the chance of breakage. This applies
to starting work m the morning in cold rooms, and to new wheels
which have been stored in a cold place.
— Wheels should be occasionally tested
balance, and rebalanced if necessary.

112. Replacing hood.
113. Starting new wheels.—
114. Applying work.

115. Test for balance.
for
116. Truing.—W heels worn out of round shall be trued by a
competent man. Wheels out of balance through wear, which can
not be balanced by truing or dressing, shall be removed from the
machine.
117. Wet grinding wheels.— Wheels used in wet grinding should

not be allowed to stand partly immersed in the water. The watersoaked portion may throw the wheel dangerously out of balance.
A ll wet tool grinders which are not so designed as to provide
constant supply of fresh water shall be thoroughly drained at the
end of each day’s work and a fresh supply provided just before
starting.
— Grinding on the flat sides of straight wheels
is often hazardous and should not be allowed on such operations
when the sides of the wheel are appreciably worn thereby or when
any considerable or sudden pressure is brought to bear against
the sides.
— Wheel dressers, excepting the diamond
type, shall be equipped with guards over the tops of the cutters to
protect the operator from flying pieces of broken cutters or wheel
particles.
— The space about the machine should be
kept light, dry, and as free as possible from obstructions.
— Care should be exercised so that the spindle
will not become sufficiently heated to damage the wheel.

a

118. Side grinding.

119. Dresser guards.

1100. Grinding room.
1102. Lubrication.




INDEX
Page.
Abrasive wheel, definition.................................
3
Adjustment of work rest........................................ 12
Applying work, method of............................... 18
Balance and finish of flanges................................. 14
Balance, testing wheels for................................ 18
Bands, protection:
Definition of.........................................
4
Specifications for...................................... -. 13
Bench and floor stands, exposure allowed___
6
Blotters..................................................................... 16
Breakages, wheel, inspection after...................... 18
Bushings, general requirements........................... 16
Cast hood:
Definition......................................................
4
Specifications. (See Hoods.)
Castings, specifications for.................................
9
Chucks, protection:
Definition of..................................................
4
Specifications for.......................................... 13
Compressible washers......................................... 16
Connecting members of hoods, specifications
for........................................................................ 12
Connection requirements for hoods................. 11
Construction guide for hoods.............................
9
Control of speed adjustment............................. 18
Cracked wheels, inspection for......................... 5,16
Cup wheels, protection for................................. 13
Cylinder wheels, protection for........................ 13
Cylindrical grinders, exposure allowed...........
6
Definitions............................................................ 3,4
Degree of taper for protection flanges.............. 15
Dimensions. (See article in question.)
Direction of rotation...........................................
5
Direction of spindle thread...............................
5
Dresser guara....................................................... 18
Dry grinding, dust exhaust provisions........... 12
Dust exhaust provisions.................................... 12
Enclosure requirements.....................................
7
Exhaust, dust, provisions for........................... 12
Exposure adjustment.........................................
7
Exposure allowable:
Bench and floor stands...............................
6
Cylindrical grinders.....................................
6
Surface grinders............................................
6
Swin g frame and portable..........................
7
Top grinding.................................................
7
Fabricated hood:
Definition......................................................
4
Specifications. (See Hoods.)
Fastenings and mounting for hoods................
6
i inish and balance of flanges............................ 14
Fit of flanges........................................................ 14
Fit of wheel.......................................................... 16
Flange facings...................................................... 16
Flanges, general requirements.......................... 13
Flanges, protection:
Definition of..................................................
4
Specifications for............................................ 14-16
Flanges, straight, specifications for.................. 14
Flanges, tapered, specifications for.................. 15
Floor and bench stands, exposure allowed...
6
Grinding room, general conditions.................. 18
Handling and storage, precautions..................
5
Holes in flanges, size of...................................... 14
Holes in wheels, size of.......................................
6




Hoods, protection:
Page.
Connecting members, specifications......... 11,12
Connection requirements............................ 11
Construction guide—fabricated hoods__
9
Definition.......................................................
4
Dimensions for peripheral and side mem­
bers..............................................................
8
D ust exhaust provision................................. 12
7
Enclosure requirements..............................
Exposure adjustment..................................
7
Exposure for bench and floor stands.......
6
Exposure for cylindrical grinders.............
6
Exposure for surface grinders....................
6
Exposure for swing frame grinders...........
7
Exposure for top grinding..........................
7
Fixed members.............................................
7
General requirements..................................
6
Material specifications.................................
9
Mounting and fastenings............................
6
Hoods, replacing after mounting wheel......... 18
Hub flanges, definition.......................................
4
Inspection of equipment after wheel break­
ages..................................................................... 18
Inspection of wheels before mounting............. 16
5
Inspection of wheels on receipt........................
Internal grinding, exception to protection
requirements.....................................................
4
Lead-faced flanges............................................... 16
6
Length of spindle thread...................................
Lighting conditions in grinding room............. 18
Limit stop for size of wheel...............................
5
Lubrication of machine...................................... 18
Machine:
Direction of spindle thread........................
5
General requirements..................................
5
Length of spindle thread............................
6
Limit stop......................................................
5
Rigidity, supports, etc................................
5
Spindle size....................................................
5
Wheel hole size.............................................
6
Material for flanges, specifications.................... 13
Material for hoods, specifications......................
9
Mounting of hoods...............................................
6
Mounting of wheels............................................. 16
Nut, spindle end, tightening of........................ 16
Opening in hoods, size of................................... 6,7
Peripheral member for hoods, dimensions—
8
Portable and swing frame grinders, exposure
allowed...............................................................
7
Protection bands. (See Bands.)
Protection chucks. (See Chucks.)
Protection devices, general requirements___
4
Protection flanges. (See Flanges.)
Protection hoods. (See Hoods.)
Recess in flanges.................................................. 14
Recommended and maximum speeds............ 17
Responsibility for care, etc................................ 18
Rests, work.......................................................... 12
Revolutions per minute and surface speeds.. 17
5
Rigidity ofsupports............................................
4
Ring flanges, definition......................................
Ring wheels, sectional, protection for............. 13
5
Rotation, direction of.........................................
3
Scope of code........................................................
Sectional ring wheels, protection for............... 13
Side grinding restriction.................................... 18

19

20

INDEX,
Tapered flanges:
Page.
Degree of taper......................
15
Dimensions.............................
15
General requirements...........
15
Test:
Balance...................................
18
Speed.......................................
17,18
Thread, spindle:
5
Direction of............................
Length of................................
6
Tightening of nut.........................
16
Top grinding, exposure allowed.
7
Truing of wheel............................
18
Washers, compressible........................................ 16
Wet grinding, provisions for............................. 18

Page.
Side members of hoods, dimensions................
8
Size. (See article in question.)
Speed adjustment control.................................. 18
Speed in revolutions per minute and surface
feet per minute................................................. 17
Speed test.............................................................. 17,18
Speeds, recommended and maximum............ 17
Spindle sizes..........................................................
5
Spindle thread:
Direction of...................................................
5
Length of.......................................................
6
Starting new wheels, test before...................... 18
Storage of wheels.................................................
5
Straight flanges, dimensions............................. 14
Supports, rigidity of...........................................
5
Surface grinders, exposure allowed.................
6
Swing frame grinders, exposure allowed........
7




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