Tools for woodworking - Safety requirements - Part 1: Milling tools, circular saw blades

This document specifies all hazards arising from the use of tools for woodworking machines, and describes the methods for the elimination or reduction of these hazards by tool design and by the provision of information. This document deals with milling tools (bore mounted, shank mounted), integrated tools and circular saw blades.

Maschinen-Werkzeuge für Holzbearbeitung - Sicherheitstechnische Anforderungen - Teil 1: Fräs- und Hobelwerkzeuge, Kreissägeblätter

Outils pour le travail du bois - Prescriptions de sécurité - Partie 1 : Outils de fraisage, lames de scies circulaires

Orodja za obdelavo lesa - Varnostne zahteve - 1. del: Rezkalno orodje, listi krožnih žag

Ta dokument določa vse nevarnosti, ki izhajajo iz uporabe orodij za obdelavo lesa, in opisuje metode za zmanjšanje ali odpravo teh nevarnosti z zasnovo orodja in zagotavljanjem informacij. Ta dokument obravnava frezala (pritrjena v izvrtino, pritrjena na držalo), integrirana orodja in krožne žage.

General Information

Status
Published
Public Enquiry End Date
07-Aug-2016
Publication Date
03-Jan-2018
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
05-Dec-2017
Due Date
09-Feb-2018
Completion Date
04-Jan-2018

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SLOVENSKI STANDARD
SIST EN 847-1:2018
01-februar-2018
Orodja za obdelavo lesa - Varnostne zahteve - 1. del: Rezkalno orodje, listi krožnih
žag
Tools for woodworking - Safety requirements - Part 1: Milling tools, circular saw blades
Maschinen-Werkzeuge für Holzbearbeitung - Sicherheitstechnische Anforderungen - Teil
1: Fräs- und Hobelwerkzeuge, Kreissägeblätter
Outils pour le travail du bois - Prescriptions de sécurité - Partie 1 : Outils de fraisage,
lames de scies circulaires
Ta slovenski standard je istoveten z: EN 847-1:2017
ICS:
25.100.20 Orodja za frezanje Milling tools
25.100.40 Žagni listi Saws
79.120.10 Lesnoobdelovalni stroji Woodworking machines
SIST EN 847-1:2018 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 847-1:2018

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SIST EN 847-1:2018


EN 847-1
EUROPEAN STANDARD

NORME EUROPÉENNE

November 2017
EUROPÄISCHE NORM
ICS 79.120.10 Supersedes EN 847-1:2013
English Version

Tools for woodworking - Safety requirements - Part 1:
Milling tools, circular saw blades
Outils pour le travail du bois - Prescriptions de sécurité Maschinen-Werkzeuge für Holzbearbeitung -
- Partie 1 : Outils de fraisage, lames de scies circulaires Sicherheitstechnische Anforderungen - Teil 1: Fräs-
und Hobelwerkzeuge, Kreissägeblätter
This European Standard was approved by CEN on 21 August 2017.

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, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 847-1:2017 E
worldwide for CEN national Members.

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SIST EN 847-1:2018
EN 847-1:2017 (E)
Contents Page

European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms, definitions, symbols and abbreviations . 6
3.1 Terms and definitions . 6
3.2 Symbols and abbreviations for cutting materials . 11
4 List of significant hazards . 14
5 Design requirements . 14
5.1 General requirements for milling tools and circular saw blades . 14
5.2 Special requirements for milling tools for machines with hand feed . 22
6 Tool identification . 28
6.1 Marking of milling tools for integrated feed other than shank mounted tools or
integrated tools . 28
6.2 Marking of milling tools for machines with hand feed other than shank mounted
tools or integrated tools . 28
6.3 Marking of integrated tools . 28
6.4 Marking of shank mounted tools . 29
6.5 Marking of tool sets . 29
6.6 Marking of circular saw blades . 30
6.7 Marking of cutting parts and deflectors . 30
7 Information for use . 31
7.1 General . 31
7.2 Safe working practice . 31
7.3 Maintenance of tools . 32
7.4 Handling . 32
Annex A (informative) Maintenance and modification of milling tools and related
components . 34
A.1 General . 34
A.2 Minimum dimensions . 34
A.3 Retipping, exchange of tips on composite tools and circular saw blades . 34
A.4 Milling tools marked with MAN. 34
A.5 Balance of milling tools . 34
A.6 Marking . 34
A.7 Information . 34
Annex B (normative) Palmqvist Toughness Test. 35
Bibliography . 36

2

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SIST EN 847-1:2018
EN 847-1:2017 (E)
European foreword
This document (EN 847-1:2017) has been prepared by Technical Committee CEN/TC 142
“Woodworking machines - Safety”, the secretariat of which is held by UNI.
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 May 2018, and conflicting national standards shall be
withdrawn at the latest by May 2018.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 847-1:2013.
According to the CEN-CENELEC Internal Regulations, the national standards organisations 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, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
3

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SIST EN 847-1:2018
EN 847-1:2017 (E)
Introduction
The extent to which hazards are covered is indicated in the scope of this document.
The requirements of this document concern designers, manufacturers, suppliers and importers of tools
for cutting wood and materials with similar physical characteristics to wood.
This document also includes information that the manufacturer will provide to the user.
4

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SIST EN 847-1:2018
EN 847-1:2017 (E)
1 Scope
This European Standard specifies all hazards arising from the use of tools for woodworking machines,
and describes the methods for the elimination or reduction of these hazards by tool design and by the
provision of information. This European Standard deals with milling tools (bore mounted, shank
mounted) and circular saw blades, designed for chip removal machining (cutting) of wood and
materials with similar physical characteristics to wood, hereinafter referred to as “tools”. The hazards
are listed in Clause 4.
This European Standard does not cover any hazard related to the strength of shank of shank mounted
milling tools.
This European Standard does not apply to boring bits, eccentric single router cutters, cutters with
cutting circle less than 16 mm and to tools used in rotary knife lathes and copying lathes where the
hazard of ejection and contact with the tool is always prevented by a system of fixed guards and/or
movable guards interlocked with guard-locking and/or self-closing guards.
This European Standard is not applicable for tools according to this scope, which are manufactured
before the date of its publication.
NOTE For woodworking machines and materials with similar physical characteristics to wood, see
ISO 19085-1.
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 847-2:2017, Tools for woodworking - Safety requirements - Part 2: Requirements for the shank of
shank mounted milling tools
EN 23878, Hardmetals - Vickers hardness test (ISO 3878)
ISO 286-2, 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
5

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EN 847-1:2017 (E)
3 Terms, definitions, symbols and abbreviations
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1.1
milling tool
rotating cutting tool (e.g. milling cutter, planing cutter, thicknessing cutter) normally having its main
feed direction perpendicular to the rotation axis, for working various surfaces
Note 1 to entry: The cutting edge of the cutting part can be
- parallel to the axis of rotation,
- square to the axis of rotation, or
- a profile which is a combination of the two.
The tool can be
- a one-piece tool,
- a composite tool,
- a complex tool, or
- in the form of a tool set.
3.1.2
circular saw blade
rotating cutting tool for cross-cutting or ripping
Note 1 to entry: The tools cut on the periphery and on both flanks simultaneously, and can be
- a one-piece tool,
- a composite tool,
- a complex tool, or
- in a form of a stack of circular saw blades with equal diameter.
3.1.3
one-piece tool
tool without bonded or detachable parts: the body and the cutting parts are one-piece
3.1.4
composite tool
tool where the cutting parts (tips) are firmly connected by bonding to the body, e.g. welding, brazing,
adhesive fixing
3.1.5
complex tool
tool where one or more cutting parts are exchangeably mounted in a body through detachable fixing
elements
Note 1 to entry: The cutting parts can be one-piece or composite.
3.1.6
tool set
one or more individual tools (e.g. milling tool, circular saw blade) clamped together on a tool carrier
(e.g. sleeve, arbor) designed to function as one tool
6

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3.1.7
shank tool
tool with integrated shank (e.g. cylindrical, HSK, taper)
3.1.8
integrated tool
milling tool where the body is part of the machine and only the cutting parts are exchangeable
3.1.9
body
part of the tool which holds the cutting parts or on which the cutting parts are formed
3.1.10
cutting part
functional part or parts of the tool each comprised of chip producing elements
Note 1 to entry: The cutting edges, face and flank are therefore elements of the cutting part. In the case of a
multi-toothed cutter tool, each tooth has a cutting part.
[SOURCE: ISO 3002-1:1982, 3.2.5]
3.1.11
auxiliary cutting part
additional cutting part with a cutting width of less than or equal to 12 mm and a radial cutting edge
projection to the body of less than or equal to 13 mm
EXAMPLE Inserts for grooving, edge rounding and chamfering.
3.1.12
spur
cutting part which operates both on its periphery and on its flank
Note 1 to entry: The spur projects from the major cutting edge in radial, and if applicable, in axial direction. A
spur is either a separate cutting part (see Figure 1) or a part of the major cutting edge.
Dimensions in millimetres

Key
1 screw at the choice of the manufacturer
Figure 1 — Milling tool with a spur
7

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EN 847-1:2017 (E)
3.1.13
cutting diameter
d (cutting radius r )
1 1
maximum possible diameter of the cutting edge
Note 1 to entry: For tools where various cutting parts can be mounted, d1 is defined by the maximum possible
cutting part
Note 2 to entry: See Figure 2.

key
a Shaded area
Figure 2 — Cutting diameter and cutting width
3.1.14
cutting width
b
1
maximum possible width of the cutting edge
Note 1 to entry: For tools where various cutting parts can be mounted, b is defined by the maximum possible
1
cutting part
Note 2 to entry: See Figure 2.
3.1.15
deflector
projecting part exchangeably mounted or firmly connected by bonding to the body or part of the body
which performs chip thickness limitation
Note 1 to entry: The deflector can also be called a “counter-knife”.
Note 2 to entry: See Figures 3 b), 3 c), 3 d), 3 e) and 3 g).
3.1.16
cutting part projection
t
difference between the radius r of the cutting circle and the radius r of the back supporting circle
1 5
where t = r – r
1 5
Note 1 to entry: See Figure 3.
8

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EN 847-1:2017 (E)
3.1.17
radial cutting edge projection
c
r
difference between the deflector (not round form tool) or the body (round form tool) and the cutting
edge measured in the direction of the normal to the profile
Note 1 to entry: See Figures 2 and 3.
3.1.18
axial cutting edge projection
c
a
distance measured axially between the axial cutting edge and the body or the deflector
Note 1 to entry: See Figures 2, 3 a), 3 d) and 3 g)
3.1.19
round form tool
tool where the body has a circular shape in any cross section perpendicular to the rotational axis of the
tool and which performs chip thickness limitation
Note 1 to entry: Auxiliary cutting parts with a deflector or spurs are not to be considered.
Note 2 to entry: See Figure 3 a)
3.1.20
not round form tool
tool where chip thickness limitation is performed by a deflector or where the cross section of the body
is not circular
Note 1 to entry: See Figures 3 b), 3 c), 3 d), 3 e), 3 f) and 3 g)
3.1.21
round form tool set
functional unit consisting of a number of individual not round form and/or round form tools clamped
together and forming a round form tool with radial gaps of less than 5 mm and axial gaps less than
15 mm and the top and the bottom side is a full round
3.1.22
tool combination
unit consisting of a number of loose tools arranged in a variable sequence to each other or extendable in
an axial position to each other
3.1.23
friction lock fixing
fixing where the relative change of position in radial direction during rotation is prevented only by the
friction forces
Note 1 to entry: See Figure 4.
3.1.24
form lock fixing
fixing where the relative change of position in radial direction during rotation is prevented by the form
and arrangement of the components
Note 1 to entry: See Figure 5.
9

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3.1.25
radial and axial approach flats
flat on the radial and/or axial surface of the deflector or of the body, in front of the deflector edge
Note 1 to entry: See Figure 6.
3.1.26
radial approach angle
τ
r
angle between the approach flat and the tangent to the deflector circle at the deflector edge or to the
body circle at the point where the radial approach flat begins
Note 1 to entry: See Figure 6.
3.1.27
axial approach angle
τ
a
angle between a plane perpendicular to the axis of the tool and the axial approach flat
Note 1 to entry: See Figure 6.
3.1.28
basic number of teeth
number of teeth cutting in each part of the profile
3.1.29
hand feed
manual holding and/or guiding of the workpiece or of a machine element incorporating a tool
Note 1 to entry: Hand feed includes the use of hand-operated carriage on which the workpiece is placed
manually or clamped and the use of demountable power feed unit
3.1.30
integrated feed
feed mechanism for the workpiece or tool which is integrated with the machine and where the
workpiece or machine element with incorporated tool is held and controlled mechanically during the
machining operation
3.1.31
maximum rotational speed
maximum rotational speed for the operation for which the tool is designed
3.1.32
speed range
minimum and maximum rotational speeds within which the tool spindle or tool is designed to operate
3.1.33
loading the machine
manual or automatic placing of the workpiece onto a carriage, magazine, lift, hopper, movable bed,
conveyor or the presentation of the workpiece to an integrated feed device
10

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3.1.34
demountable power feed unit
feed mechanism which is mounted on the machine so that it can be moved from the working position
without the use of a spanner or similar additional device
3.1.35
ejection
uncontrolled movement of the workpiece, parts of it, parts of machines or uncontrolled movement of
hand-held machines during processing
3.1.36
kickback
particular form of ejection describing the uncontrolled movement of the workpiece or parts of it
opposite to the direction of feed during processing
3.1.37
chip breaking item
item suitable to deflect the chip (e.g. to upset the chip) with the aim of reducing the presplitting of the
workpiece material
Note 1 to entry: The chip breaking item can be a separate or an integral element of the cutting part.
3.1.38
gullet width
s
tangential distance from the cutting edge to the point at which the contour of the tool abandons the
circle with radius r
2
Note 1 to entry: See Figure 3 a) and Figure 3 g).
3.2 Symbols and abbreviations for cutting materials
SP Alloyed tool steel (minimum 0,6 % C and no more than 5 % alloy constituents)
HL High alloyed tool steel (more than 5 % alloy units, e.g. 12 % Cr)
HS High speed steel (more than 12 % total of alloying components W, Mo, V, Co)
SC Coated steel
HW Uncoated hardmetal on tungsten carbide base [ISO 513]
HC Coated hardmetal [ISO 513]
ST Cast cobalt-based alloys, e.g. stellites
DP Polycrystalline diamond [ISO 513]
DM Monocrystalline diamond
11

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In Figure 3 a) is r = r .
2 5
Figure 3 — Deflector

Figure 4 — Friction lock fixing
12

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EN 847-1:2017 (E)

Figure 5 — Form lock fixing

Key
1
radial approach flat
2 axial approach flat
Figure 6 — Radial and axial approach flats
13

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EN 847-1:2017 (E)
4 List of significant hazards
Table 1 shows the list of significant hazards.
Table 1 — Significant hazards
Hazard Condition or causes of hazard Corresponding clause
related to the tool of EN 847–1
Cutting and severing cutting hazard when mounting 5, 7
or dismounting the tool
kickback or contact with the 5
rotating tool
Ejection of parts disintegration or partial break 5, 6, 7
up to tool body
incorrect assembly of tool 5, 7
components
movements of cutting parts fixed 5
by friction
fly in/out of cutting parts or 5
separate components
unbalance of the tool while 5
rotating
kickback when machining 5
fixing of the tool on the machine 5, 7
spindle
modification of position of tool 5
components
Vibrations unbalance of tool 5
5 Design requirements
5.1 General requirements for milling tools and circular saw blades
5.1.1 General
Tools shall be designed and made of such materials in order that they will withstand the forces and
loads expected when used and maintained in compliance with the manufacturer's instructions.
5.1.2 Safety requirements and/or measures
One-piece tools, composite tools and complex tools shall be designed with a safety factor as given in
Table 2.
14

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Table 2 — Safety factors
Type of tool Method of procedure Safety factor
One-piece (solid) Calculation of stresses or Safety factor of 4 means
and composite tools centrifugal test against fracture n = 2 × n
p max
Complex tools Test procedure Safety factor of 2,25 means
described under 5.1.3.4 n = 1,5 × n
p max
NOTE np is the test speed for overspeed test.
An overspeed type test is required for complex tools.
For tools with a cutting radius of r ≤ 20 mm a load of 50 N/mm shall be assumed. For tools with a
1
cutting radius of r > 20 mm the following formula applies for the calculation of the cutting force per
1
millimetre:
30⋅P
6
Mot
F ⋅10 (1)
m
rb⋅⋅n ⋅π
1 1 max
where
F is the specific cutting force [N/mm];
m
P is the spindle motor power [kW];
Mot
r is the cutting radius [mm];
1
b is the cutting width [mm];
1
−1
n is the maximum rotational speed [min ].
max
Verification: By checking calculations or using the test procedure.
5.1.3 Special requirements for complex tools
5.1.3.1 Form lock fixing and friction lock fixing
Form lock fixing shall be used for complex tools with the exception of the following cases where friction
lock fixing may also be used:
— cutting parts used in milling tools for surface planing and thicknessing machines whose cutting
width is at least 150 mm;
— cutting parts (except moulding and bevel blades) used in milling tools for machines with integrated
feed;
— tools used in chipping and flaking machines with integrated feed.
Verification: By checking relevant drawings, measurement and visual inspection of the tool.
5.1.3.2 Clamping parts
The design of a complex tool, which includes a deflector, shall ensure that clamping of the knife can only
be achieved with the deflector in position.
Form lock fixing shall ensure a positive mechanical fastening between the separable tool elements, and
shall not rely on friction alone between the clamped parts. Examples of positive mechanical locks are:
pin(s), screw(s), slot(s), notch(es).
15
=

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SIST EN 847-1:2018
EN 847-1:2017 (E)
Where a pin lock is used, at least 1 pin (see Figure 7) shall be used for cutting part width up to 30 mm
and at least 2 pins for cutting part width over 30 mm.

Figure 7 — Complex tool pin locking
For planing and combined planing and thicknessing machine milling tools, where fixing of the wedges is
by means of screws (see Figures 4 b) and 5 b)), at least two screws are required for each wedge.
The distance between the back of the wedges and the body shall not exceed 7 mm when the cutting part
is in position (see Figure 4 b)).
Verification: By checking the relevant drawing, measurement and visual inspection of the tool and by
checking that the knife cannot be clamped without the deflector in position.
5.1.3.3 Position of the chip breaker
When using a chip breaking item, c shall be minimum 1,0 mm (see Figure 8).
c
For round form tools with a cutting edge projection of c and c ≤ 1,1 mm a c of minimum 0,6 mm is
r a c
allowed (see Figure 8).

Figure 8 — Minimum distance of the chip breaking item (c ) from the cutting edge
c
5.1.3.4 Overspeed type test
5.1.3.4.1 Test conditions
The strength of complex tools to withstand the expected centrifugal forces to be seen in use is
considered proven if, during an overspeed type test at a rotational test speed of
–1
n = 1,5 ⋅ n  [n in min ] (2)
p max p
the relative displacements of detachable tool parts shall at no point be greater than indicated in the test
procedure (see 5.1.3.4.2).
Tension elements shall be tightened to torque figures indicated by the manufacturer.
5.1.3.4.2 Test procedure
a) Measure the tool dimensions.
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b) Run the tool at its maximum rotational speed n for 1 min.
max.
c) Stop and re-measure the tool; measured displacements shall not be greater than 0,15 mm.
d) Bring the tool to the test speed n for 1 min.
p
e) Stop and re-measure the tool and compare the results with those obtained from the third step c).
The compared displacements shall not exceed 0,15 mm.
The overspeed test shall be conducted with blanks for the largest cutting diameter and the largest
cutting width.
In deviation from the specifications given above, for milling tools with centrifugal wedges, greater
displacements of the centrifugal wedge are permissible in consideration of the following conditions:
— the tool is calculated for the most unfavourable tolerances and for test speed n with the stresses in
p
the elastic range;
— the displacement of the centrifugal wedges shall not adversely influence the function and behaviour
of the tool (kickback behaviour, chip removal, etc.);
— for the testing of the tool with centrifugal wedge it is required to apply the test as defined, whereby
the wedge shall be positioned correctly in accordance with the manufacturer's instructions before
the first step a) of the test.
5.1.4 Cutting part thickness and cutting part projection
5.1.4.1 Steel based cutting parts
One-piece or composite cutting parts (e.g. HS, HL and SP cutting materials) and cutting parts with steel
body shall be designed and manufactured in a way which ensures that the relation between cutting part
thickness and cutting part projection is according to the formulae below.
Cutting part thickness and cutting part projection are shown in Figure 9.
Cutting part thickness = a
Cutting part projection = t
0,4 mm ≤ a ≤ 1,0 mm t = a (a = t) (3)
max min
1,0 mm < a ≤ 2,0 mm t = 4 × a – 3 mm (a = 0,25 × t + 0,75 mm) (4)
max min
a > 2,0 mm t = 8 × a – 11 mm (a = 0,125 × t + 1,4 mm) (5)
max min
17

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Key
1 cutting part
2 support body
3 form lock fixing
Figure 9 — Examples of steel based cutting part thickness and cutting part projection
5.1.4.2 Hardmetal cutting parts
One-piece hardmetal (e.g. HW, HC) cutting parts, composite milling tools and circular saw blades shall
be designed and manufactured in a way which ensures that the relation between cutting part thickness
and cutting part projection is according to the below formulae.
Cutting part thickne
...

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