EN 847-2:2017
(Main)Tools for woodworking - Safety requirements - Part 2: Requirements for the shank of shank mounted milling tools/circular saw blades
Tools for woodworking - Safety requirements - Part 2: Requirements for the shank of shank mounted milling tools/circular saw blades
This European Standard specifies the determination of the maximum speed for given eccentricity at clamping devices for the shank strength of milling tools with cylindrical and taper shank. It also specifies the marking of the tool. Bore mounted tools which are mounted on an arbor shall be considered as a shank mounted tool.
Maschinen-Werkzeuge für Holzbearbeitung - Sicherheitstechnische Anforderungen - Teil 2: Anforderungen für den Schaft von Fräswerkzeugen/Kreissägeblätter
Outils pour le travail du bois - Prescriptions de sécurité - Partie 2 : Prescriptions pour les queues des fraises à queue
Orodja za obdelavo lesa - Varnostne zahteve - 2. del: Zahteve za držalo rezkalnih orodij
Ta evropski standard določa največje hitrosti za dano ekscentričnost pri vpenjalnih napravah za moč stojala frezal s cilindričnim in stožčastim stojalom. Prav tako določa označevanje orodja. Orodja, ki se pritrdijo v izvrtino in so pritrjena na stojalo, naj bi bila obravnavana kot orodja, pritrjena na stojalo.
General Information
- Status
- Published
- Publication Date
- 31-Oct-2017
- Withdrawal Date
- 30-May-2018
- Technical Committee
- CEN/TC 142 - Woodworking machines - Safety
- Drafting Committee
- CEN/TC 142/WG 8 - Tooling
- Current Stage
- 9060 - Closure of 2 Year Review Enquiry - Review Enquiry
- Start Date
- 04-Jun-2023
- Completion Date
- 04-Jun-2023
Relations
- Effective Date
- 08-Jun-2022
Overview
EN 847-2:2017 (CEN) is the European safety standard that defines requirements for the shank of shank‑mounted milling tools and bore‑type tools mounted on arbors used in woodworking. It specifies how to determine the maximum permissible rotational speed for a given eccentricity at the clamping device, sets geometric and tolerance requirements (e.g. clamping length, shank diameter tolerances), and requires tool marking relevant to shank strength. The standard complements EN 847-1:2017 and references EN ISO 12100:2010 for risk assessment.
Key Topics
- Scope and applicability
- Applies to cylindrical and taper (7/24) shanks, HSK interfaces and bore‑mounted tools (arbors).
- Applies also for tools with cutting diameter < 16 mm; not retroactive to tools manufactured before publication.
- Shank geometry and tolerances
- Minimum clamping lengths specified (e.g. l = 20 mm for small shanks; larger values scale with diameter).
- Shank diameter tolerances: h6 for d ≥ 12 mm and h8 for d < 12 mm.
- Maximum speed and stability calculations
- Procedures and formulae to calculate maximum permissible rotational speed (n) based on shank strength, eccentricity at the clamping device, material properties (modulus of elasticity, fatigue strength), section properties (I, W) and mass distribution.
- Use the lower of (a) shank‑strength limit and (b) centrifugal‑force limit per EN 847‑1.
- Typical example values: e_sp = 0.06 mm for CNC clamping devices and e_sp = 0.1 mm for hand‑held tool clamping (values for design and testing).
- Safety factor f = 4 (and other specified safety or lifetime factors for HSK).
- HSK and arbor requirements
- Separate stability method for HSK-mounted tools, based on balance of moments, clamping force and expected gravity‑centre displacement.
- Rules for bore‑mounted tools and minimum hub diameters when mounted on arbors.
- Marking
- Requirements for marking cylindrical shanks to communicate limits and ensure traceability.
Applications
- Practical use by:
- Tool manufacturers designing shanks, cutters and arbors to legal safety limits.
- Machine builders and integrators specifying compatible clamping systems and allowable speeds.
- Safety engineers, test labs and conformity assessors who verify shank strength and mark tools accordingly.
- Workshop managers and end users selecting tooling and speed limits to avoid shank failure and vibration hazards.
- Ensures safer high‑speed operation, reduced risk of tool breakage, and better balance quality in woodworking milling and sawing operations.
Related Standards
- EN 847-1:2017 - Tools for woodworking - Safety requirements - Part 1: Milling tools, circular saw blades
- EN ISO 12100:2010 - Safety of machinery - General principles for design - Risk assessment and risk reduction
Keywords: EN 847-2:2017, tools for woodworking, shank mounted milling tools, shank strength, maximum speed, eccentricity, HSK, arbor, clamping devices, safety requirements.
Frequently Asked Questions
EN 847-2:2017 is a standard published by the European Committee for Standardization (CEN). Its full title is "Tools for woodworking - Safety requirements - Part 2: Requirements for the shank of shank mounted milling tools/circular saw blades". This standard covers: This European Standard specifies the determination of the maximum speed for given eccentricity at clamping devices for the shank strength of milling tools with cylindrical and taper shank. It also specifies the marking of the tool. Bore mounted tools which are mounted on an arbor shall be considered as a shank mounted tool.
This European Standard specifies the determination of the maximum speed for given eccentricity at clamping devices for the shank strength of milling tools with cylindrical and taper shank. It also specifies the marking of the tool. Bore mounted tools which are mounted on an arbor shall be considered as a shank mounted tool.
EN 847-2:2017 is classified under the following ICS (International Classification for Standards) categories: 79.120.10 - Woodworking machines. The ICS classification helps identify the subject area and facilitates finding related standards.
EN 847-2:2017 has the following relationships with other standards: It is inter standard links to EN 847-2:2013. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
You can purchase EN 847-2:2017 directly from iTeh Standards. The document is available in PDF format and is delivered instantly after payment. Add the standard to your cart and complete the secure checkout process. iTeh Standards is an authorized distributor of CEN standards.
Standards Content (Sample)
SLOVENSKI STANDARD
01-februar-2018
1DGRPHãþD
SIST EN 847-2:2014
Orodja za obdelavo lesa - Varnostne zahteve - 2. del: Zahteve za držalo rezkalnih
orodij
Tools for woodworking - Safety requirements - Part 2: Requirements for the shank of
shank mounted milling
Maschinen-Werkzeuge für Holzbearbeitung - Sicherheitstechnische Anforderungen - Teil
2: Anforderungen für den Schaft von Fräswerkzeugen/Kreissägeblätter
Outils pour le travail du bois - Prescriptions de sécurité - Partie 2 : Prescriptions pour les
queues des fraises à queue
Ta slovenski standard je istoveten z: EN 847-2:2017
ICS:
25.100.20 Orodja za frezanje Milling tools
79.120.10 Lesnoobdelovalni stroji Woodworking machines
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EN 847-2
EUROPEAN STANDARD
NORME EUROPÉENNE
November 2017
EUROPÄISCHE NORM
ICS 79.120.10 Supersedes EN 847-2:2013
English Version
Tools for woodworking - Safety requirements - Part 2:
Requirements for the shank of shank mounted milling
tools/circular saw blades
Outils pour le travail du bois - Prescriptions de sécurité Maschinen-Werkzeuge für Holzbearbeitung -
- Partie 2 : Prescriptions pour les queues des fraises à Sicherheitstechnische Anforderungen - Teil 2:
queue Anforderungen für den Schaft von
Fräswerkzeugen/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 847-2:2017 E
worldwide for CEN national Members.
Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 List of significant hazards . 6
5 Safety requirements . 6
5.1 General requirements for cylindrical shank . 6
5.2 Stability of the shank of shank mounted tools . 7
5.3 Stability of HSK mounted tools . 13
6 Marking of tools with cylindrical shank . 15
Annex A (informative) Examples of calculation . 17
A.1 Example of calculation of n . 17
shank
A.2 Examples of calculations of n . 18
HSK
Annex B (normative) Method of measuring the eccentricity at clamping devices . 19
Annex C (informative) Recommended minimum clamping forces . 20
Bibliography . 21
European foreword
This document (EN 847-2:2017) 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 847-2:2013.
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.
Introduction
The content of this European Standard is aimed at eliminating hazards which can lead to overloading of
the shank of shank mounted milling tools for woodworking by excessive rotational speeds.
1 Scope
This European Standard specifies the determination of the maximum speed for given eccentricity at
clamping devices for the shank strength of milling tools with cylindrical and taper shank. It also
specifies the marking of the tool. Bore mounted tools e.g. milling tools, circular saw blades which are
mounted on an arbor should be considered as a shank mounted tool.
This European Standard complements EN 847-1:2017 and applies also for shank tools with a cutting
diameter of less than 16 mm.
This European Standard is not applicable for shanks of tools according to this scope, which are
manufactured before the date of its publication.
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 847-1:2017, Tools for woodworking — Safety requirements — Part 1: Milling tools, circular saw
blades
EN ISO 12100:2010, Safety of machinery — General principles for design — Risk assessment and risk
reduction (ISO 12100:2010)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 847-1:2017 and the following
apply.
3.1
7/24 shank
SK
type of tool holder with a 7/24 cone ratio taper
3.2
hollow taper shank
HSK
type of tool holder with a short hollow taper with high positioning accuracy and high grade of rigidity
that contacts the spindle on two surfaces
3.3
arbor
device to be mounted on the machine spindle interface and which is designed to carry bore type cutting
tools
4 List of significant hazards
Table 1 shows the list of significant hazards.
Table 1 — List of significant hazards
Hazard according to Condition or causes of Corresponding clause of
hazard related to the tool EN 847–2
EN ISO 12100:2010
Mechanical hazards due to:
Breaking of the tool 5
Inadequacy of mechanical strength
Vibration Dynamic unbalance of tool 5
Variations in the rotational speed of
Breaking of the tool 5
tools
5 Safety requirements
5.1 General requirements for cylindrical shank
The minimum value for the clamping length l shall be as given in Table 2.
e min
Table 2 — Minimum clamping length l
e min
d ≤ 10 mm 10 mm < d < 25 mm d ≥ 25 mm
2 2 2
l = 20 mm l = 2 ⋅ d (mm) l = 1,8 ⋅ d (mm)
e min e min 2 e min 2
The tolerance of the shank diameter d shall be h6 for d ≥ 12 mm and h8 for d < 12 mm.
2 2 2
5.2 Stability of the shank of shank mounted tools
5.2.1 General
For descriptions of symbols for the stability of the shank of shank mounted tools, see Table 3.
Table 3 — Stability of the shank of shank mounted tools — Symbols and units
Symbol Description Unit
diameter
a) shank diameter d
d mm
b) cone diameter d
c) with axial force: d (calculated); without axial force: d
4 arbor
d maximum diameter of the cutting part mm
cut
shank diameter, see Figure 2 mm
d
d cone diameter, see Figure 3 mm
calculated hub diameter, see Figure 4 mm
d
d shank diameter of the arbor, see Figure 4 mm
arbor
− 2
E modulus of elasticity of the shank material N mm
maximum permissible eccentricity at clamping device mm
e
sp
f form factor —
f safety factor (f = 4) —
s s
axial clamping force, see Figure 4 N
F
a
balance quality grade of the tool set (individual tools, arbor, spacers, HSK):
− 1
G product of the permissible eccentricity and the angular velocity according to EN 847– mm s
1:2017
I second moment of area mm
height of cutting part mm
l
cut
l free shank length mm
l , l , l , . axial distance of the gravity centre of the mass m , m , m , . mm
1 2 3 1 2 3
axial distance of gravity centre, see Figure 1 mm
l
s
l clamping length mm
e
total length of shank mm
l
g
m , m , m , . mass of the parts of the tool set, see Figure 1 g
1 2 3
m mass of the cutting part in the area of l , see Figure 2 g
cut cut
m* mass of the tool in the area (l + l ) g
0 cut
m * reduced mass of the cutting part, see Figure 2 g
cut
− 1
n operational speed min
− 1
n maximum permissible rotational speed with regard to shank strength min
shank
S centre of gravity —
W section modulus mm
− 2
σ fatigue strength under reversed bending stresses of shank material N mm
w
− 3
ρ density of material (e.g. shank, tool body, spacers) g mm
The maximum permissible rotational speed of shank mounted tools n shall be calculated referring
shank
to the shank strength.
For calculation of n with a given e the following formula applies:
shank sp
W ⋅ W ⋅ ⋅ l
σ σ
s
2 w w 6
− G + + ⋅ + ⋅
G e 10
sp
*
3 ⋅ E ⋅ I
⋅ l
m
s
(1)
= ⋅
n
shank
f ⋅ π
l
s W ⋅ ⋅
σ
s
w
+
e
sp
3 ⋅ E ⋅ I
with
d
I = π⋅ (2)
d
W π⋅ (3)
For balance quality, see EN 847-1:2017.
Better balance quality grades for tools or tool sets may be applied, if these can be permanently
maintained due to the tool design.
NOTE 1 The safety requirements for th
...
EN 847-2:2017は、木工用工具の安全要件に関する重要な標準です。この標準は、シャンクマウント型ミリングツールや円鋸刃のシャンクに関する要件を明確に定義しており、特にシャンクの強度に関連する最大速度の決定方法を特定しています。具体的には、クランピング装置の偏心度に基づいて最大速度を設定することを目的としています。 この標準の強みは、木工用工具の安全性を確保するための具体的で明確なガイドラインを提供する点です。シャンクの安全性と効率を向上させるために、厳格な試験方法と条件が設定されています。その結果、メーカーは工具の設計時にこの基準を遵守することで、安全で信頼性の高い製品を市場に提供することが可能になります。 また、標準はツールのマーキングに関する要件も含まれており、使用者が安全性の評価を容易に行えるようになっています。このように、EN 847-2:2017はシャンクマウント型工具の安全性を高めるための基盤となるものであり、業界におけるその重要性は非常に高いです。全体として、木工業界においてEN 847-2:2017は、工具の設計、製造、使用における安全性を確保する上で不可欠な標準となっています。
The EN 847-2:2017 standard provides comprehensive safety requirements specifically tailored for shank mounted milling tools and circular saw blades in woodworking applications. The scope of this European Standard is crucial as it outlines the methodology for determining the maximum operational speed for given eccentricities at clamping devices, directly addressing the shank strength of milling tools with both cylindrical and taper shank configurations. This is important for ensuring the safe use of tooling in woodworking, where precision and safety are paramount. One of the standout strengths of the EN 847-2:2017 standard is its emphasis on the marking of the tools. This requirement aids in the identification and compliance verification, fostering accountability and enhancing operational safety among users and manufacturers. The inclusion of bore mounted tools as shank mounted tools reflects a practical understanding of the industry, ensuring that a broader range of tooling is covered under safety regulations. This inclusion is particularly significant, as it supports the safe integration of various tool types used in woodworking. The relevance of the EN 847-2:2017 standard cannot be overstated, as it serves as a benchmark for safety in the woodworking industry. It not only protects operators and manufacturers by establishing clear guidelines but also promotes industry best practices that contribute to the overall advancement of tool safety standards. As woodworking technologies evolve, standards like EN 847-2:2017 play a pivotal role in maintaining safety and efficiency, ensuring that shank mounted milling tools and circular saw blades are both safe and effective for use.
Die EN 847-2:2017 ist ein entscheidendes Dokument im Bereich der Holzverarbeitung, das spezifische Sicherheitsanforderungen für Werkzeugmaschinen festlegt. Diese Norm konzentriert sich insbesondere auf die Anforderungen für den Schaft von schaftmontierten Fräswerkzeugen und Kreissägeblättern. Die Festlegung maximales Drehzahl für gegebene Exzentrizität an Spannvorrichtungen ist ein zentrales Element, das sicherstellt, dass diese Werkzeuge unter sicheren Bedingungen betrieben werden können. Einer der größten Stärken dieser Norm ist die klare Definition der Grenzwerte und Anforderungen an die Schaftfestigkeit bei zylindrischen und konischen Schäften. Dadurch wird nicht nur die Sicherheit der Benutzer erhöht, sondern auch das Risiko von Unfällen und Werkzeugversagen erheblich minimiert. Zudem trägt die Norm zur Standardisierung und Qualitätskontrolle in der Holzindustrie bei. Ein weiterer wichtiger Aspekt der EN 847-2:2017 ist die Regelung zur Kennzeichnung der Werkzeuge. Durch die Festlegung spezifischer Markierungsvorgaben wird sichergestellt, dass die Benutzer jederzeit über die wesentlichen Eigenschaften und Sicherheitsmerkmale der Werkzeuge informiert sind. Dies fördert nicht nur die Sicherheit, sondern auch das Vertrauen in die Produkte auf dem Markt. Insgesamt ist die EN 847-2:2017 von großer Relevanz für Hersteller und Anwender von Holzbearbeitungswerkzeugen. Sie bietet einen umfassenden Rahmen für die Sicherheit und Qualität von schaftmontierten Fräswerkzeugen und Kreissägeblättern und stellt sicher, dass diese gemäß den präzisen Anforderungen der europäischen Standards betrieben werden.
La norme EN 847-2:2017 est un document essentiel qui établit des exigences de sécurité pour les outils de menuiserie, en se concentrant spécifiquement sur le shank des outils de fraisage montés sur shank et des lames de scie circulaire. Son champ d'application est clairement défini, permettant de déterminer la vitesse maximale admissible en fonction de l'excentricité des dispositifs de serrage pour la résistance du shank des outils de fraisage, qu'ils aient un shank cylindrique ou conique. Parmi les forces majeures de cette norme, on retrouve son approche méthodique pour garantir la sécurité des utilisateurs et la performance des outils. En spécifiant les exigences de marquage des outils, la norme facilite également l'identification et la traçabilité des produits, renforçant ainsi la confiance des professionnels dans les équipements qu'ils utilisent. De plus, le fait que la norme couvre également les outils montés sur un arbre en tant qu'outils montés sur shank élargit son application, permettant une meilleure harmonisation des pratiques de sécurité dans l'industrie de la menuiserie. La pertinence de la norme EN 847-2:2017 dans le domaine du travail du bois ne saurait être sous-estimée. En fournissant des directives claires et des critères d'évaluation pour les outils de fraisage et les lames de scie circulaire, elle contribue à réduire les risques d'accidents et à promouvoir un environnement de travail plus sûr pour les artisans et les professionnels du secteur. Son adoption est essentielle pour toute entreprise cherchant à respecter les normes de sécurité en vigueur et à assurer une qualité optimale de ses outils.
SIST EN 847-2:2018 표준은 목공 도구에 대한 안전 요구사항을 정립하며, 특히 밀링 공구 및 원형 톱날의 샹크 부분에 중점을 두고 있습니다. 이 표준은 원형 또는 테이퍼 샹크를 가진 밀링 도구의 샹크 강도를 평가하기 위해 클램핑 장치에서의 주어진 편심에 따른 최대 속도의 결정 방법을 규정합니다. 이 표준의 강점은 명확한 안전 기준을 제공함으로써 목재 가공 산업에서의 사고를 줄이고 사용자의 안전을 보장하는 데 기여한다는 점입니다. 또한, 공구의 표기를 규정하여 사용자가 공구의 성능 및 적절한 사용 방법을 쉽게 이해할 수 있도록 돕습니다. SIST EN 847-2:2018은 샹크 장착 도구에 대한 명확한 정의를 통해 이들을 적용하기 쉬운 통일된 기준으로 만들어, 관련 산업의 표준화와 효율성을 향상시키는 데 매우 중요한 역할을 합니다. 이 표준의 적용은 목공 도구의 안전성과 성능을 극대화하며, 산업 내에서의 신뢰성을 높이는 데 필수적입니다. 따라서 EN 847-2:2017은 목공 도구의 안전 요구사항에 대한 중요한 지침을 제공하며, 기능성과 안전성을 함께 고려한 설계와 사용이 이루어질 수 있도록 하는 실질적인 표준으로 자리잡고 있습니다.
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