Bsi bs en 13236 2010 + a1 2015

!Significant changes between EN 13236:2001 and EN 13236:2010 were as follows:" a the standard was technically and editorially revised and partly adapted to EN 12413:2007 about bonded abr

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BSI Standards Publication

BS EN 13236:2010

Safety requirements for superabrasive products

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EN 13236:2010+A1:2015 It supersedes BS EN 13236:2010 which is withdrawn.

The start and finish of text introduced or altered by amendment is indicated in the text by tags Tags indicating changes to CEN text carry the number of the CEN amendment For example, text altered by CEN amendment A1 is indicated by .

The UK participation in its preparation was entrusted to Technical Committee MTE/13, Grinding wheels, abrasive tools, paper and cloths, and powders.

A list of organizations represented on this committee can be obtained

on request to its secretary.

This publication does not purport to include all the necessary provisions

of a contract Users are responsible for its correct application.

Published by BSI Standards Limited 2016 ISBN 978 0 580 90463 9

Amendments/corrigenda issued since publication

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Safety requirements for superabrasive products

Prescriptions de sécurité pour les produits

superabrasifs Sicherheitsanforderungen für Schleifwerkzeuge mit Diamant oder Bornitrid

This European Standard was approved by CEN on 16 October 2010 and includes Amendment 1 approved by CEN on 17

November 2015

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member

This European Standard exists in three official versions (English, French, German) A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom

EUROPEAN COMMITTEE FOR STANDARDIZATION

C OMITÉ E URO PÉEN DE N ORMA LI SA TIO N EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels

worldwide for CEN national Members Ref No EN 13236:2010+A1:2015 E

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Contents

Page

European foreword 5

Introduction 7

1 Scope 8

2 Normative references 8

3 Terms, definitions and symbols 8

3.1 General 8

3.2 Grinding machines 8

3.3 Grinding method 9

3.4 Type of application 9

3.5 Symbols 11

3.6 Other symbols 11

4 List of significant hazards 12

5 Safety requirements 12

5.1 General requirements 12

5.2 Requirements for precision superabrasive grinding and cutting-off wheels 13

5.2.1 Bore tolerances 13

5.2.2 Sequence of maximum operating speeds 13

5.2.3 Safety factors 13

5.2.4 Maximum operating speeds 13

5.2.5 Blotters 14

5.3 Requirements for non-precision cutting-off wheels 14

5.3.5 Requirements for the metal blank 16

5.3.6 Requirements for the connection of the superabrasive section to the metal blank 19

5.3.7 Tensioning of non-precision cutting-off wheels 21

5.3.8 Limitation of sides abrasives and/or superabrasives coating 21

5.4 Requirements for diamond wires 21

5.4.1 General 21

5.4.2 Requirements 21

5.5 Requirements for mounted points 22

5.5.1 Spindle diameter tolerances 22

5.6 Requirements for other superabrasive products for non-precision grinding 22

5.6.1 Bore diameter tolerances 22

5.6.5 Requirements for the connection of the abrasive section to the core 23

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EN 13236:2010+A1:2015 (E)

2

European foreword 5

Introduction 7

1 Scope 8

2 Normative references 8

3 Terms, definitions and symbols 8

3.1 General 8

3.2 Grinding machines 8

3.3 Grinding method 9

3.4 Type of application 9

3.5 Symbols 11

3.6 Other symbols 11

4 List of significant hazards 12

5 Safety requirements 12

5.1 General requirements 12

5.2 Requirements for precision superabrasive grinding and cutting-off wheels 13

5.2.5 Blotters 14

5.3 Requirements for non-precision cutting-off wheels 14

5.3.5 Requirements for the metal blank 16

5.3.6 Requirements for the connection of the superabrasive section to the metal blank 19

5.3.7 Tensioning of non-precision cutting-off wheels 21

5.3.8 Limitation of sides abrasives and/or superabrasives coating 21

5.4 Requirements for diamond wires 21

5.4.1 General 21

5.4.2 Requirements 21

5.5 Requirements for mounted points 22

5.5.1 Spindle diameter tolerances 22

5.6 Requirements for other superabrasive products for non-precision grinding 22

5.6.1 Bore diameter tolerances 22

5.6.5 Requirements for the connection of the abrasive section to the core 23

5.7 Marking 24

EN 13236:2010+A1:2015 (E) 3 6 Verification of the safety requirements 24

6.1 Verification of the general requirements 24

6.1.1 Visual inspection 24

6.1.2 Ring test 24

6.2 Verification of the strength requirements 24

6.2.1 Verification of the safety factor 24

6.2.2 Verification of the bending moment of non-precision cutting-off wheels 24

6.2.3 Verification of the strength requirements for other superabrasive products for non-precision grinding 27

6.2.4 Verification methods for diamond wires 28

6.3 Verification of marking 30

6.4 Verification of the requirements for blotters 30

6.5 Verification of tensioning of non-precision cutting-off wheels 30

7 Information for use 31

Annex A (normative) Marking 32

A.1 Content of the marking 32

A.1.1 Marking requirements 32

A.1.2 Additional inscriptions 34

A.1.3 Multiple or gang mounted wheels 34

A.2 Execution of the marking 35

Annex B (normative) Colour codes 36

Annex C (informative) Mounted points 37

C.1 Example of calculation of the maximum permissible speed of rotation 37

C.2 Example for the application of the calculation method 40

C.2.1 Types of mounted points 40

C.2.2 Assumptions for the calculation 41

C.2.3 Maximum permissible speeds of rotation 42

Annex D (normative) Reconditioning of cutting-off wheels according to 5.3.6.4 44

D.1 Preconditions for reconditioning 44

D.2 Additional marking requirements 44

Annex E (informative) Speed conversion table 46

Bibliography 49

Figures Figure 1 — Position of cuts and openings in steel blanks 18

Figure 2 — Example of cut-outs and openings 19

Figure 3 — Segmented cutting-off wheels: Dimensions of segment height X1 25

Figure 4 — Example of a bending test device for segmented cutting-off wheels 25

Figure 5 — Cutting-off wheels with continuous rim: Dimensions of segment height X1 26

Figure 6 — Example of a bending test device for cutting-off wheels with continuous rim 27

Figure 7 — Example of a shearing force test device 28

Tables Table 1 — Grinding method, type of machine, type of application 10

EN 13236:2010+A1:2015 (E)

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Table 2 — Symbols 11

Table 3 — Other symbols 12

Table 4 — List of significant hazards 12

Table 5 — Safety factors for precision superabrasive grinding and cutting-off wheels 13

Table 6 — Maximum operating speeds as a function of the bond type 14

Table 7 — Safety factors for non-precision cutting-off wheels 15

Table 9 — Dimensions of blanks for dry cutting-off 16

Table 10 — Dimensions of blanks for wet cutting-off 17

Table 11 — Bending strength σb for cutting-off wheels for the use on hand-held cutting-off machines depending on segment height X1 and segment length L2 20

Table 12 — Minimum bending moment Mb 20

Table 13 — Safety factors for other superabrasive products for non-precision grinding 23

Table A.1 — Marking of superabrasive products 32

Table A.2 — Restrictions of use (RE) 34

Table B.1 — Colour codes and design of colour codes 36

Table C.1 — Designation of the calculation quantities 39

Table C.2 — Designation of mounted points 40

Table C.3 — Characteristics for the calculation of maximum speeds of rotation 41

Table C.4 — Mounted points, cylindrical shape, plain spindles (ZYN) vitrified bond (V) 42

Table C.5 — Mounted points, cylindrical shape, reduced spindles (ZYA), vitrified bond (V) 42

Table C.6 — Mounted points, cylindrical shape, plain spindle Schaft (ZYN), electroplated bond (G) 43

Table E.1 — Speed conversion 46

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EN 13236:2010+A1:2015 (E)

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Table 2 — Symbols 11

Table 3 — Other symbols 12

Table 4 — List of significant hazards 12

Table 5 — Safety factors for precision superabrasive grinding and cutting-off wheels 13

Table 7 — Safety factors for non-precision cutting-off wheels 15

Table 9 — Dimensions of blanks for dry cutting-off 16

Table 10 — Dimensions of blanks for wet cutting-off 17

Table 11 — Bending strength σb for cutting-off wheels for the use on hand-held cutting-off machines depending on segment height X1 and segment length L2 20

Table 12 — Minimum bending moment Mb 20

Table 13 — Safety factors for other superabrasive products for non-precision grinding 23

Table A.1 — Marking of superabrasive products 32

Table A.2 — Restrictions of use (RE) 34

Table B.1 — Colour codes and design of colour codes 36

Table C.1 — Designation of the calculation quantities 39

Table C.2 — Designation of mounted points 40

Table C.3 — Characteristics for the calculation of maximum speeds of rotation 41

Table C.4 — Mounted points, cylindrical shape, plain spindles (ZYN) vitrified bond (V) 42

Table C.5 — Mounted points, cylindrical shape, reduced spindles (ZYA), vitrified bond (V) 42

Table C.6 — Mounted points, cylindrical shape, plain spindle Schaft (ZYN), electroplated bond (G) 43

Table E.1 — Speed conversion 46

EN 13236:2010+A1:2015 (E)

5

European foreword

This document (EN 13236:2010+A1:2015) has been prepared by Technical Committee CEN/TC 143

“Machine tools - Safety”, the secretariat of which is held by SNV

This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by June 2016 and conflicting national standards shall be withdrawn at the latest by June 2016

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights The provisions of this European Standard need not be mandatory to superabrasive products manufactured the first 12 months after publication of this European Standard

This document includes Amendment 1 approved by CEN on 17 November 2015

This document supersedes !EN 13236:2010"

The start and finish of text introduced or altered by amendment is indicated in the text by tags !"

!Significant changes between EN 13236:2001 and EN 13236:2010 were as follows:"

a) the standard was technically and editorially revised and partly adapted to EN 12413:2007 about bonded abrasive products and EN 13743:2009 about coated abrasive products;

b) the term "burst speed factor" was included in Table 2, Table 5, Table 7 and Table 13;

c) in the requirements it is now distinguished between precision and non-precision cutting-off wheels; d) new 5.3.5.3 defines restrictions in design and position of cuts and openings in the metal blank of cutting-off wheels for hand-held applications;

e) changed 5.3.6.2 on dimensional limitations and bending moment for segmented non-precision cutting-off wheels for hand-held applications, with requirements now depending on segment height and segment length;

f) requirements for reconditioned non-precision cutting-off wheels were included in new 5.3.6.4 and new normative Annex D;

g) Clause 6 was shortened to verification of safety requirements The scope of inspection and testing has been deleted because it is the responsibility of the manufacturer to put in place respective test procedures that give them the confidence that all safety requirements defined in this standard are respected;

h) the requirements for colour code stripes were deleted in Annex A and are now presented in new Annex B;

i) Table A.3 and Table A.4 about restrictions for use were combined to one table and thereby adapted to

EN 12413 and EN 13743;

j) Clause A.2 about execution of the marking was simplified;

EN 13236:2010+A1:2015 (E)

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k) Annex B about blotters was deleted and part of its content was included in 5.2.5;

l) Annex C about mounted points was completely revised and shortened;

m) Annex D with the speed conversion table (now Annex E) was editorially revised and maximum operating speeds above 320 m/s were deleted;

n) Annex E about shapes and dimensions of grinding wheels and cutting-off wheels had become obsolete with publication of ISO 6104 and was therefore deleted;

o) Annex F about grain sizes and concentration for diamond and cubic boron nitride had become obsolete with publication of ISO 6106 and was therefore deleted

According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom

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EN 13236:2010+A1:2015 (E)

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k) Annex B about blotters was deleted and part of its content was included in 5.2.5;

l) Annex C about mounted points was completely revised and shortened;

m) Annex D with the speed conversion table (now Annex E) was editorially revised and maximum

operating speeds above 320 m/s were deleted;

n) Annex E about shapes and dimensions of grinding wheels and cutting-off wheels had become obsolete

with publication of ISO 6104 and was therefore deleted;

o) Annex F about grain sizes and concentration for diamond and cubic boron nitride had become obsolete

with publication of ISO 6106 and was therefore deleted

According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following

countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech

Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,

Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,

Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom

The extent to which hazards are covered is indicated in the scope of this European Standard

EN 13236:2010+A1:2015 (E)

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1 Scope

!This European Standard only applies to superabrasives products containing natural or synthetic diamond or cBN (cubic boron Nitride) It includes precision grinding and cutting-off wheels, non-precision cutting-off wheels, diamond wires, mounted points and other superabrasive products for non-precision grinding It also applies to reconditioned superabrasive cutting-off wheels."

This European Standard specifies requirements and/or measures for the removal or reduction of hazards resulting from the design and application of the superabrasive products

This European Standard contains also procedures and tests for verification of the compliance with the requirements as well as safety information for use which is to be made available to the user by the manufacturer

The hazards taken into consideration are listed in Clause 4

This European Standard does not apply to bonded abrasive products, coated abrasive products, rotating dressing tools, truers nor any non-rotating superabrasive products

2 Normative references

!The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application For dated references, only the edition cited applies For undated references, the latest edition of the referenced document (including any amendments) applies."

EN ISO 286-2:2010, Geometrical product specifications (GPS) — ISO code system for tolerances on linear

sizes — Part 2: Tables of standard tolerance classes and limit deviations for holes and shafts (ISO 286-2:2010)

ISO 22917, Superabrasives — Limit deviations and run-out tolerances for grinding wheels with diamond or

cubic boron nitride

3 Terms, definitions and symbols

For the purposes of this document the following terms and definitions apply

stationary grinding machine

grinding machine being fixed in position during operation

! Note 1 to entry: " See for example EN 13218

3.2.2

mobile grinding machine

grinding machine not being fixed in position during operation

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EN 13236:2010+A1:2015 (E)

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1 Scope

!This European Standard only applies to superabrasives products containing natural or synthetic

diamond or cBN (cubic boron Nitride) It includes precision grinding and cutting-off wheels, non-precision

cutting-off wheels, diamond wires, mounted points and other superabrasive products for non-precision

grinding It also applies to reconditioned superabrasive cutting-off wheels."

This European Standard specifies requirements and/or measures for the removal or reduction of hazards

resulting from the design and application of the superabrasive products

This European Standard contains also procedures and tests for verification of the compliance with the

requirements as well as safety information for use which is to be made available to the user by the

manufacturer

The hazards taken into consideration are listed in Clause 4

This European Standard does not apply to bonded abrasive products, coated abrasive products, rotating

dressing tools, truers nor any non-rotating superabrasive products

2 Normative references

!The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application For dated references, only the edition cited applies For undated references,

the latest edition of the referenced document (including any amendments) applies."

EN ISO 286-2:2010, Geometrical product specifications (GPS) — ISO code system for tolerances on linear

sizes — Part 2: Tables of standard tolerance classes and limit deviations for holes and shafts (ISO 286-2:2010)

ISO 22917, Superabrasives — Limit deviations and run-out tolerances for grinding wheels with diamond or

cubic boron nitride

3 Terms, definitions and symbols

For the purposes of this document the following terms and definitions apply

stationary grinding machine

grinding machine being fixed in position during operation

! Note 1 to entry: " See for example EN 13218

3.2.2

mobile grinding machine

grinding machine not being fixed in position during operation

! Note 1 to entry: "Mobile grinding machines are manually guided (but not supported) by hand during use, e.g

floor grinding machines

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3.2.3 hand-held grinding machine

grinding machine being held in the hand during the grinding process

! Note 1 to entry: "See for example EN 792-7, EN 792-9, EN 60745-2-3 and EN ISO 19432

3.2.4 grinding machine with totally enclosed working area

stationary grinding machine being protected in such a way by separating guards that machining processes including loading and unloading of workpieces are carried out inside them and persons are protected against hazards generated by bursting of an abrasive product

3.3 Grinding method

3.3.1 peripheral grinding

grinding with the periphery of the wheel with no or limited side loads

3.3.2 face grinding

grinding with the face of the wheel

3.3.3 cutting-off

slotting with the periphery of the cutting-off wheel

3.4 Type of application

See Table 1

3.4.1 mechanically guided grinding

grinding process with feed movements of the abrasive product and/or workpiece guided by mechanical means

3.4.2 manually guided grinding

grinding process with feed movements of the abrasive product and/or the workpiece manually guided by the operator

3.4.3 hand-held grinding

grinding process with grinding machine entirely guided by the operator's hands

EN 13236:2010+A1:2015 (E)

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peripheral speed of a rotating

vbr

rotating abrasive product breaks due to centrifugal force m/s

vbr min

rotating abrasive product shall

at least reach without bursting due to centrifugal force

m/s

Bursting speed divided by maximum operating speed:

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Table 3 — Other symbols

4 List of significant hazards

Table 4 — List of significant hazards Hazard designation Hazardous situations

(Examples) Relevant clauses in this standard

— improper design 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, Annex C and Annex D

— improper handling and

— improper use (mounting and

hand-held machines caused by:

5 Safety requirements

5.1 General requirements

Superabrasive products shall be designed and manufactured in such a way that they resist the forces and loads that are to be expected when used as intended They shall not present visible defects affecting safety and shall comply with the requirements listed in the following clauses

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Table 3 — Other symbols

4 List of significant hazards

Table 4 — List of significant hazards Hazard designation Hazardous situations

(Examples) Relevant clauses in this standard

— improper design 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, Annex C and Annex D

— improper handling and

— improper use (mounting and

hand-held machines caused by:

5 Safety requirements

5.1 General requirements

Superabrasive products shall be designed and manufactured in such a way that they resist the forces and

loads that are to be expected when used as intended They shall not present visible defects affecting safety

and shall comply with the requirements listed in the following clauses

5.2.2 Sequence of maximum operating speeds

Precision superabrasive grinding and cutting-off wheels shall be manufactured for maximum operating speeds conforming to the following sequence:

< 16 — 20 — 25 — 32 — 35 — 40 — 45 — 50 — 63 — 80 — 100 — 125 — 140 — 160 — 180 — 200 —

225 — 250 — 280 — 320 in m/s

NOTE For conversion of maximum operating speeds into speeds of rotation for different outside diameters D of

the abrasive product, see Annex E

Mechanically

Mechanically guided grinding with totally enclosed working area

Stationary and mobile grinding machines

Manually guided grinding

5.2.4 Maximum operating speeds

Precision superabrasive grinding and cutting-off wheels shall comply with the classification of the sequence

of maximum operating speeds in 5.2.2 up to the maximum values given in Table 6

In the totally enclosed working area, the maximum operating speeds given in Table 6 may be exceeded, if the safety factor required in Table 5 is complied with

EN 13236:2010+A1:2015 (E)

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Table 6 — Maximum operating speeds as a function of the bond type

Core Abrasive section

Maximum operating speed vs

Resinoid

Manufactured on core,

Connected to core, e.g cemented, screwed,

in the way that it loses its compressibility and physical function

Blotters can serve as a label for the marking provided the marking requirements of this standard are met and the blotter is firmly attached to the wheel

5.3 Requirements for non-precision cutting-off wheels

5.3.1 Bore tolerances

The tolerance class for bores for non-precision cutting-off wheels is H9 as per EN ISO 286-2:2010

Non-precision cutting-off wheels shall be manufactured for maximum operating speeds conforming to the following sequence:

20 — 25 — 32 — 35 — 40 — 45 — 50 — 63 — 80 — 100 in m/s

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EN 13236:2010+A1:2015 (E)

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Core Abrasive section

Resinoid

Manufactured on core,

Connected to core, e.g cemented, screwed,

Blotters shall be supplied by the manufacturer, supplier or importer where these are required for a safe

mounting and use of the superabrasive product

Blotters shall be made of suitable compressible material Shape, dimensions and material shall be adapted to

application and intended use When water-based coolants are used the blotter material shall not be affected

in the way that it loses its compressibility and physical function

Blotters can serve as a label for the marking provided the marking requirements of this standard are met

and the blotter is firmly attached to the wheel

5.3 Requirements for non-precision cutting-off wheels

5.3.1 Bore tolerances

The tolerance class for bores for non-precision cutting-off wheels is H9 as per EN ISO 286-2:2010

Non-precision cutting-off wheels shall be manufactured for maximum operating speeds conforming to the

following sequence:

20 — 25 — 32 — 35 — 40 — 45 — 50 — 63 — 80 — 100 in m/s

cutting-Mechanically

Mechanically guided cutting-off with totally enclosed working area

Stationary and mobile cutting-off machines

Manually guided

Hand-held

Non-precision cutting-off wheels shall comply with the sequence of maximum operating speeds in 5.3.2 up

to the maximum values given in Table 8

Core Cutting rim (abrasive

section)

Type of application

Maximum operating speed

EN 13236:2010+A1:2015 (E)

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5.3.5 Requirements for the metal blank

5.3.5.1 Requirements for the metal blank of cutting-off wheels for dry cutting-off

5.3.5.1.1 Dimensions

Dimensions of metal blanks of non-precision cutting-off wheels for dry cutting-off, see Table 9

Table 9 — Dimensions of blanks for dry cutting-off Type of machine

Outside diameter D1 of the blank

5.3.5.1.2 Material and hardness of blanks for laser welded cutting-off wheels

The material used for the blank shall be steel which shall have the necessary properties enabling it to produce adequate joint strength when welding it to the segments For example, alloyed cold worked steels having a maximum carbon content of 0,27 % are suitable

Blanks shall have a minimum hardness of 20 HRC for outside diameter D1 ≤ 230 mm and a minimum

hardness of 24 HRC for outside diameter D1> 230 mm

5.3.5.1.3 Material and hardness of blanks for sintered and direct melted cutting-off wheels

Tool steels, grade to the choice of the manufacturer

5.3.5.1.4 Surface finish of the entire slot area

Cutting-off wheels shall be manufactured in such a way that the surface finish in the area of the slots does not cause crack formation

5.3.5.1.5 Other requirements

Blanks shall be free from visible defects

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EN 13236:2010+A1:2015 (E)

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5.3.5 Requirements for the metal blank

5.3.5.1 Requirements for the metal blank of cutting-off wheels for dry cutting-off

5.3.5.1.1 Dimensions

Dimensions of metal blanks of non-precision cutting-off wheels for dry cutting-off, see Table 9

Table 9 — Dimensions of blanks for dry cutting-off Type of machine

Outside diameter D1 of the blank

5.3.5.1.2 Material and hardness of blanks for laser welded cutting-off wheels

The material used for the blank shall be steel which shall have the necessary properties enabling it to

produce adequate joint strength when welding it to the segments For example, alloyed cold worked steels

having a maximum carbon content of 0,27 % are suitable

Blanks shall have a minimum hardness of 20 HRC for outside diameter D1 ≤ 230 mm and a minimum

hardness of 24 HRC for outside diameter D1> 230 mm

5.3.5.1.3 Material and hardness of blanks for sintered and direct melted cutting-off wheels

Cutting-off wheels shall be manufactured in such a way that the surface finish in the area of the slots does

not cause crack formation

Dimensions of metal blanks for non-precision cutting-off wheels for wet cutting-off, see Table 10

Table 10 — Dimensions of blanks for wet cutting-off

5.3.5.2.2 Material

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b) Cuts outside the flange area other than circular holes and elliptical holes with a ratio of large to small

radius ≤ (2:1) shall end at a distance of ≥ 15 % of the blank radius D1/2 away from the closest gullet or outside diameter of the blank See also Figure 1

c) Inside the flange area no cuts or holes other than one drive pin hole or two circular cuts with approximately radial orientation for fixing of functional elements are allowed

Key

no cuts allowed in this area

Figure 1 — Position of cuts and openings in steel blanks 5.3.5.3.2 Dimensions and distribution of narrow laser cuts

a) Cuts outside the flange area shall have a dimension in radial direction of ≤ 40 % of the blank radius D1/2 b) The minimum distance between cuts outside the flange area at any point of the cut-out shall be ≥ 15 %

of the radius D/2 of the cutting-off wheel

c) Laser cuts shall start and end with a spiral

5.3.5.3.3 Dimensions and distribution of wide cut-outs and openings

a) Wide cut-outs and openings in blanks shall have a dimension in radial direction of ≤ 15 % of the radius

D/2 of the cutting-off wheel with an opening angle of 15° at maximum, see Figure 2 as an example

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EN 13236:2010+A1:2015 (E)

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b) Cuts outside the flange area other than circular holes and elliptical holes with a ratio of large to small

radius ≤ (2:1) shall end at a distance of ≥ 15 % of the blank radius D1/2 away from the closest gullet or

outside diameter of the blank See also Figure 1

c) Inside the flange area no cuts or holes other than one drive pin hole or two circular cuts with

approximately radial orientation for fixing of functional elements are allowed

Key

no cuts allowed in this area

Figure 1 — Position of cuts and openings in steel blanks 5.3.5.3.2 Dimensions and distribution of narrow laser cuts

a) Cuts outside the flange area shall have a dimension in radial direction of ≤ 40 % of the blank radius D1/2

b) The minimum distance between cuts outside the flange area at any point of the cut-out shall be ≥ 15 %

of the radius D/2 of the cutting-off wheel

c) Laser cuts shall start and end with a spiral

5.3.5.3.3 Dimensions and distribution of wide cut-outs and openings

a) Wide cut-outs and openings in blanks shall have a dimension in radial direction of ≤ 15 % of the radius

D/2 of the cutting-off wheel with an opening angle of 15° at maximum, see Figure 2 as an example

EN 13236:2010+A1:2015 (E)

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Key

1 flange area

Figure 2 — Example of cut-outs and openings

b) The total area of wide cut-outs and openings in blanks shall be ≤ 20 % of the area of the blank

5.3.5.4 Heat treatment of all metal blanks

If slots or openings are produced by laser cutting, the steel blank shall be annealed if the micro hardness is

> 500 HV in the heat affected zone, in order to achieve a hardness of ≤ 500 HV

5.3.6 Requirements for the connection of the superabrasive section to the metal blank 5.3.6.1 Connection of segments to the metal blank

The segments for hand-held cutting-off wheels for dry cutting-off shall be connected to the metal blank by welding, sintering, direct melting or infiltration attachment processes

5.3.6.2 Tolerances and bending moment for segmented non-precision cutting-off wheels

For segmented non-precision cutting-off wheels for the use on hand-held cutting-off machines, the ratio of

segment height to thickness of the core, X1/E shall be ≤ 8,5

For segmented non-precision cutting-off wheels the strength of the joint between the metal blank and the segment shall be designed to comply with the following bending moment:

2 v b

Mb is the bending moment;

Lv is the length of the bond interface between segment and core;

E is the thickness of the core;

σb is the bending strength value, see a) and b) below

EN 13236:2010+A1:2015 (E)

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The bending strength values to be included in Equation (1) are:

a) for cutting-off wheels for the use on stationary and mobile cutting-off machines: σb = 450 N/mm2, and

b) for cutting-off wheels for the use on hand-held cutting-off machines σb according to Table 11

Table 11 — Bending strength σb for cutting-off wheels for the use on hand-held cutting-off machines

depending on segment height X1 and segment length L2

σb

2

X L

E of the cutting-off wheel, then the values given in Table 12 shall be fulfilled at minimum

Table 12 — Minimum bending moment Mb

Core thickness E

mm

Minimum bending

5.3.6.3 Bending moments for cutting-off wheels with continuous cutting rim in metal bond

For non-precision cutting-off wheels with continuous rim, the strength of the joint between the metal bond and the blank shall be designed to comply with the following bending moment:

where

F is the force, here: F = 125 N;

D is the outside diameter of the cutting-off wheel, expressed in m

5.3.6.4 Requirements for reconditioned non-precision cutting-off wheels

Segmented cutting-off wheels which have been equipped with new abrasive sections due to wear of the abrasive sections shall comply with the same requirements as unused cutting-off wheels

They shall comply with the marking requirements in Annex A and in addition carry the data for marking the

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EN 13236:2010+A1:2015 (E)

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The bending strength values to be included in Equation (1) are:

a) for cutting-off wheels for the use on stationary and mobile cutting-off machines: σb = 450 N/mm2, and

b) for cutting-off wheels for the use on hand-held cutting-off machines σb according to Table 11

Table 11 — Bending strength σb for cutting-off wheels for the use on hand-held cutting-off machines

depending on segment height X1 and segment length L2

σb

2

X L

≥ 750 1,5 to < 2

≥ 900 1,0 to < 1,5

If for cutting-off wheels for the use on hand-held cutting-off machines the bending moment values Mb

resulting from Equation (1) are smaller than the values given in Table 12 as a function of the core thickness

E of the cutting-off wheel, then the values given in Table 12 shall be fulfilled at minimum

Table 12 — Minimum bending moment Mb

Core thickness E

mm

Minimum bending

5.3.6.3 Bending moments for cutting-off wheels with continuous cutting rim in metal bond

For non-precision cutting-off wheels with continuous rim, the strength of the joint between the metal bond

and the blank shall be designed to comply with the following bending moment:

where

F is the force, here: F = 125 N;

D is the outside diameter of the cutting-off wheel, expressed in m

5.3.6.4 Requirements for reconditioned non-precision cutting-off wheels

Segmented cutting-off wheels which have been equipped with new abrasive sections due to wear of the

abrasive sections shall comply with the same requirements as unused cutting-off wheels

They shall comply with the marking requirements in Annex A and in addition carry the data for marking the

reconditioned state given in D.2

Reconditioning is only permitted, if the preconditions in D.1 are complied with

EN 13236:2010+A1:2015 (E)

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!

5.3.7 Tensioning of non-precision cutting-off wheels

All non-precision cutting off wheels, marked with maximum operating speed of 100 m/s for hand held cutting-off machines and steel centre diameter 300 mm to 400 mm, shall be in a tensioned state in order to minimize the risk of wobbling (excessive vibrations)

The position of neutral point shall be in an angle range between 90° to 160° in order to have a correct tensioning of the non-precision cutting off wheel."

!

5.3.8 Limitation of sides abrasives and/or superabrasives coating

Side abrasives and/or superabrasives coating is only allowed at periphery of the steel centre within a limit

x ≤ 0,05 D (distance of 5%) of steel centre diameter for all non-precision cutting off wheels marked with

maximum operating speed of 100 m/s for hand held cutting-off machines and steel centre diameter 300 mm

5.4.2 Requirements 5.4.2.1 Requirements for the support cable

Support cables for diamond wire are subject to frequent breakage due to mechanical stress or wire fatigue, depending on their construction, type of application and their operating conditions Therefore, a cable shall

be selected which has proven fatigue resistance, e.g preferably a multi-strand cable made of fine multiple wires, for example: 6 × 7 on a 19 wire core

Support cables shall have a minimum tensile strength of 800 N/mm² in relation to the wire diameter

5.4.2.2 Requirements for spring mounted diamond wire

For diamond wires where the abrasive beads are held by means of springs, press rings and spacer rings, the bore diameters of the abrasive beads shall have the following limit deviations:

a) for the new diamond wire: bore of the abrasive bead by 0,4 mm greater than the wire diameter;

b) for the used diamond wire: bore of the abrasive beads by 0,6 mm greater than the wire diameter

A maximum of 5 abrasive beads shall be mounted between two press rings

After mounting on the support cable, the support cable and the press rings shall not show any sign of breakage

The springs ends shall be close-coiled and ground at each end

5.4.2.3 Requirements for plastic and vulcanised rubber mounted diamond wires

All abrasive beads shall be mounted on the support cable by means of plastic or vulcanized rubber

EN 13236:2010+A1:2015 (E)

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5.4.2.4 Requirements for wire couplings and press rings

The wire couplings shall be capable of withstanding at least 30 % of the load capacity of the support cable The press rings shall be capable of withstanding 1/12 the load capacity of the support cable without moving

The maximum operating speed for diamond wires shall not exceed vs = 40 m/s

5.5 Requirements for mounted points

5.5.1 Spindle diameter tolerances

The tolerance class for spindle diameters for mounted points is given in ISO 22917

Mounted points shall be manufactured for maximum operating speeds conforming to the following sequence:

5 — 6 — 8 — 10 — 12 — 16 — 20 — 25 — 32 — 35 — 40 — 45 — 50 — 63 in m/s

5.5.3 Safety factors

Mounted points shall have a safety factor against bursting due to centrifugal forces of Sbr = 3 The spindle

shall have a safety factor against deflection of Sab = 1,3 Further requirements see Annex C

5.6 Requirements for other superabrasive products for non-precision grinding

5.6.1 Bore diameter tolerances

The tolerance class for bores for other superabrasive products for non-precision grinding is H9 for bore sizes H ≤ 80 mm and H7 for bore sizes H > 80 mm

Other superabrasive products for non-precision grinding shall be manufactured for maximum operating speeds conforming to the following sequence:

40 — 45 — 50 — 63 — 80 — 100 in m/s

Other superabrasive products for non-precision grinding shall have a safety factor against bursting due to centrifugal forces at their maximum operating speed as given in Table 13

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EN 13236:2010+A1:2015 (E)

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5.4.2.4 Requirements for wire couplings and press rings

The wire couplings shall be capable of withstanding at least 30 % of the load capacity of the support cable

The press rings shall be capable of withstanding 1/12 the load capacity of the support cable without moving

The maximum operating speed for diamond wires shall not exceed vs = 40 m/s

5.5 Requirements for mounted points

5.5.1 Spindle diameter tolerances

The tolerance class for spindle diameters for mounted points is given in ISO 22917

Mounted points shall be manufactured for maximum operating speeds conforming to the following

sequence:

5 — 6 — 8 — 10 — 12 — 16 — 20 — 25 — 32 — 35 — 40 — 45 — 50 — 63 in m/s

Mounted points shall have a safety factor against bursting due to centrifugal forces of Sbr = 3 The spindle

shall have a safety factor against deflection of Sab = 1,3 Further requirements see Annex C

5.6 Requirements for other superabrasive products for non-precision grinding

5.6.1 Bore diameter tolerances

The tolerance class for bores for other superabrasive products for non-precision grinding is H9 for bore

sizes H ≤ 80 mm and H7 for bore sizes H > 80 mm

Other superabrasive products for non-precision grinding shall be manufactured for maximum operating

speeds conforming to the following sequence:

40 — 45 — 50 — 63 — 80 — 100 in m/s

Other superabrasive products for non-precision grinding shall have a safety factor against bursting due to

centrifugal forces at their maximum operating speed as given in Table 13

Other superabrasive products for non-precision grinding shall comply with the sequence of maximum operating speeds given in 5.6.2 up to the maximum values given in Table 14

Table 14 — Maximum operating speeds as a function of the bond type Abrasive product application Type of

m/s

Metal

M Electroplated G

Profile grinding wheel and other superabrasive products for peripheral grindinga

Mechanically guided

Hand-held grindingAbrasive ring and other superabrasive

a Including cutting-off wheels with D < 400 mm and thickness of metal blank E ≥ 4 mm.

5.6.5 Requirements for the connection of the abrasive section to the core 5.6.5.1 For segmented dish grinding wheels for use on hand-held machines, the strength of the joint between the core and the abrasive section shall be designed to comply to one of the following requirements: a) Shear strength τS ≥ 60 N/mm2 or

b) shearing force FA ≥ 6 400 N

5.6.5.2 For all other superabrasive products for non-precision grinding which are segmented the strength of the joint between the core and the abrasive section shall be designed to comply with the requirements on the bending moments according to 5.3.6.2

If the design does not allow to apply a bending moment the requirements on the shear strength or the shearing force, respectively, according to 5.6.5.1 shall be met

EN 13236:2010+A1:2015 (E)

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5.7 Marking

Superabrasive products shall be marked according to Annex A

6 Verification of the safety requirements

6.1 Verification of the general requirements

6.1.1 Visual inspection

For visible defects affecting safety the superabrasive product is checked by visual inspection For plastic or vulcanised rubber mounted diamond wires, the saws shall be inspected for loose abrasive beads Damaged superabrasive products shall be destroyed

6.1.2 Ring test

The ring test shall be performed on all superabrasive grinding wheels with vitrified cores and an outside

diameter of D > 80 mm, with the exception of cemented or nut inserted wheels

In the ring test, the superabrasive grinding wheel is tapped with a non-metallic object An undamaged wheel produces a clear tone, a damaged wheel a dull or rattling tone

6.2 Verification of the strength requirements

6.2.1 Verification of the safety factor

Compliance with the safety factor is checked by a centrifugal force test (bursting speed test) The superabrasive product mounted in a clamping device on a suitable test rig is loaded with steadily increasing speed of rotation by centrifugal forces up to the minimum bursting speed or until bursting The speed of rotation shall be measured with an accuracy of ± 1% The speed of rotation at bursting of the superabrasive product shall be detected and recorded by a suitable device

For mounted points, the verification is carried out with an overhang length of the spindle of L0 = 0 mm

The superabrasive product passes the bursting speed test if it is run at minimum bursting speed without breaking The superabrasive product subjected to the bursting speed test shall be destroyed

Verification of the safety factor against deflection of the spindle of mounted points is carried out with a clamping length of the spindle of 10 mm or with the maximum overhang length of the spindle indicated by the manufacturer

6.2.2 Verification of the bending moment of non-precision cutting-off wheels

6.2.2.1 Segmented cutting-off wheels

In the bending test the cutting-off wheel is mounted in the area of the core so that the required minimum bending force can safely be applied The distance between the outer rim of the clamping device of the core and the bond interface is approximately 2 mm The abrasive segment to be tested is held by a clamping piece

up to a depth corresponding to the height X1 of the segment The clamping piece has approximately the same length as the segment and a similar profile to the periphery of the blank (see Figure 3 and Figure 4)

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EN 13236:2010+A1:2015 (E)

24

5.7 Marking

Superabrasive products shall be marked according to Annex A

6 Verification of the safety requirements

6.1 Verification of the general requirements

6.1.1 Visual inspection

For visible defects affecting safety the superabrasive product is checked by visual inspection For plastic or

vulcanised rubber mounted diamond wires, the saws shall be inspected for loose abrasive beads Damaged

superabrasive products shall be destroyed

6.1.2 Ring test

The ring test shall be performed on all superabrasive grinding wheels with vitrified cores and an outside

diameter of D > 80 mm, with the exception of cemented or nut inserted wheels

In the ring test, the superabrasive grinding wheel is tapped with a non-metallic object An undamaged wheel

produces a clear tone, a damaged wheel a dull or rattling tone

6.2 Verification of the strength requirements

6.2.1 Verification of the safety factor

Compliance with the safety factor is checked by a centrifugal force test (bursting speed test) The

superabrasive product mounted in a clamping device on a suitable test rig is loaded with steadily increasing

speed of rotation by centrifugal forces up to the minimum bursting speed or until bursting The speed of

rotation shall be measured with an accuracy of ± 1% The speed of rotation at bursting of the superabrasive

product shall be detected and recorded by a suitable device

For mounted points, the verification is carried out with an overhang length of the spindle of L0 = 0 mm

The superabrasive product passes the bursting speed test if it is run at minimum bursting speed without

breaking The superabrasive product subjected to the bursting speed test shall be destroyed

Verification of the safety factor against deflection of the spindle of mounted points is carried out with a

clamping length of the spindle of 10 mm or with the maximum overhang length of the spindle indicated by

the manufacturer

6.2.2 Verification of the bending moment of non-precision cutting-off wheels

6.2.2.1 Segmented cutting-off wheels

In the bending test the cutting-off wheel is mounted in the area of the core so that the required minimum

bending force can safely be applied The distance between the outer rim of the clamping device of the core

and the bond interface is approximately 2 mm The abrasive segment to be tested is held by a clamping piece

up to a depth corresponding to the height X1 of the segment The clamping piece has approximately the same

length as the segment and a similar profile to the periphery of the blank (see Figure 3 and Figure 4)

Figure 4 — Example of a bending test device for segmented cutting-off wheels

Load is applied to the clamping piece at a distance LF from the bond interface The force F applied is

measured and recorded

The bending moment acting on the bond interface is calculated from the force F and the distance LF as:

EN 13236:2010+A1:2015 (E)

Tiêu đề	Safety Requirements For Superabrasive Products
Trường học	British Standards Institution
Chuyên ngành	Standards
Thể loại	British Standard
Năm xuất bản	2016
Thành phố	Brussels

Định dạng
Số trang	54
Dung lượng	1,8 MB