EN 12965:2019

Tractors and machinery for agriculture and forestry - Power take-off (PTO) drive shafts and their guards - Safety

This document specifies safety requirements and their verification for the design and construction of power take-off (PTO) drive shafts and their guards linking a tractor or self-propelled machinery to the first fixed bearing of recipient machinery. It describes methods for the elimination or reduction of risks which need specific requirements including such risks arising from misuse, reasonably foreseeable by the manufacturer. It is applicable only to those PTO drive shafts and guards mechanically linked to the shaft by at least two bearings.
In addition, it specifies the type of information on safe working practices to be provided by the manufacturer.
This document does not deal with:
-   the guards totally covering, but not mechanically linked to, the PTO drive shaft;
-   the mechanical characteristics of PTO drive shafts, overrun devices and torque limiters;
-   general hazards which are dealt with in EN ISO 4254-1:2015 (see introduction).
Environmental aspects have not been considered in this document.
This document is not applicable to PTO drive shafts and their guards which are manufactured before the date of publication of this document by CEN.

Traktoren und Maschinen für die Land- und Forstwirtschaft - Gelenkwellen und ihre Schutzeinrichtungen - Sicherheit

Dieses Dokument enthält sicherheitstechnische Anforderungen und deren Überprüfung für die Gestaltung und Konstruktion von Gelenkwellen und ihren Schutzeinrichtungen, die für die Verbindung zwischen einem Traktor oder einer selbstfahrenden Maschine und dem ersten festen Lager der angetriebenen Maschine bestimmt sind. Es beschreibt Maßnahmen zur Beseitgung oder Verminderung von Gefährdungen, für die spezifische Anforderungen benötigt werden, einschließlich Risiken aus Fehlanwendung, die vom Hersteller vernünftigerweise vorhersehbar sind. Es gilt nur für solche Gelenkwellen und Schutzeinrichtungen, die mechanisch mit der Gelenkwelle über mindestens zwei Lager verbunden sind. Bei Verwendung mit kompatiblen Schutzeinrichtungen für die Zapfwelle (PTO, en: power take-off) des Traktors (Schutzschild, en: Master shield) oder der selbstfahrenden Maschine und der Geräteantriebswelle (PIC, en: power input connection) der angetriebenen Maschine sind die Anforderungen an die Gelenkwellen vollständig.
ANMERKUNG 1   Vollständig umschließende PIC-Schutztrichter allein bieten vollständigen Schutz.
ANMERKUNG 2   ISO 500-1 und ISO 500-2 enthalten Anforderungen für den Schutz von Traktorzapfwellen und ISO 4254-1 enthält Anforderungen für Geräteantriebswellen (PIC) von angetriebenen Maschinen, die mit dem in diesem Dokument geforderten Schutz kompatibel sind.
Zusätzlich legt es fest, welche Informationen über sicheres Arbeiten vom Hersteller zur Verfügung zu stellen sind.
Dieses Dokument behandelt nicht:
   Schutzeinrichtungen, die die Gelenkwelle vollständig umschließen, jedoch nicht mechanisch mit ihr verbunden sind;
   die mechanischen Eigenschaften von Gelenkwellen, Freiläufen und Drehmomentbegrenzern;
   allgemeine Gefährdungen, die in EN ISO 4254 1:2015 behandelt werden (siehe Einleitung);
Umweltaspekte wurden in dieser Norm nicht in Betracht gezogen.
Dieses Dokument gilt nicht für Gelenkwellen und ihre Schutzeinrichtungen, die hergestellt wurden, bevor  dieses Dokuments von CEN veröffentlicht wurde.

Tracteurs et matériels agricoles et forestiers - Arbres de transmission à cardans de prise de force et leurs protecteurs - Sécurité

Le présent document spécifie les exigences de sécurité et leur vérification pour la conception et la construction des arbres de transmission à cardans de prise de force et leurs protecteurs reliant un tracteur ou une machine automotrice au premier palier fixe d’une machine réceptrice. Il décrit des méthodes pour l’élimination ou la réduction des risques qui nécessitent des exigences spécifiques, y compris les risques associés à un mauvais usage raisonnablement prévisible par le fabricant. Il s’applique uniquement aux arbres de transmission à cardans de prise de force et leurs protecteurs, liés mécaniquement à l’arbre par au moins deux paliers. Lorsqu’elles sont utilisées avec des protecteurs compatibles avec la prise de force du tracteur (bouclier protecteur) ou de la machine automotrice et l’arbre récepteur de la machine réceptrice de puissance, les exigences relatives aux arbres de transmission à cardans de prise de force sont complètes.
NOTE 1   Des cônes de protection entièrement fermés du côté arbre récepteur de la machine assurent à eux seuls une protection complète.
NOTE 2   L’ISO 500 1 et l’ISO 500 2 fournissent des exigences relatives à la protection des prises de force des tracteurs et l’ISO 4254 1 stipule des exigences relatives aux arbres récepteurs des machines réceptrices de puissance qui sont compatibles avec les protections exigées par le présent document.
En outre, le présent document spécifie le type d’informations que le fabricant doit fournir sur les pratiques d’utilisation sûre.
Le présent document ne traite pas :
-   des protecteurs recouvrant totalement l’arbre de transmission à cardans de prise de force sans y être mécaniquement relié ;
-   des caractéristiques mécaniques des arbres de transmission à cardans de prise de force, des systèmes de roue libre et des limiteurs de couple ;
-   des phénomènes dangereux généraux qui sont traités dans l’EN ISO 4254 1:2015 (voir l’introduction).
Les aspects liés à l’environnement n’ont pas été pris en compte dans ce document.
Le présent document n’est pas applicable aux arbres de transmission à cardans de prise de force et leurs protecteurs qui ont été fabriqués avant la date de publication de ce document par le CEN.

Traktorji ter kmetijski in gozdarski stroji - Priključne gredi in njihova zaščita - Varnost

Ta evropski standard določa varnostne zahteve in njihovo potrjevanje pri projektiranju in izdelavi priključnih gredi (PTO) ter njihovih ščitnikov, ki povezujejo stroje z lastnim pogonom (ali traktorje) s prvim fiksnim ležajem prejemnega stroja. Opisuje metode za odpravljanje ali zmanjšanje tveganj s posebnimi zahtevami. Standard se uporablja le za priključne gredi in ščitnike, ki so mehansko priključeni na gred z vsaj dvema ležajema. Poleg tega določa vrsto podatkov glede varnih delovnih postopkov, ki jih mora zagotoviti proizvajalec. Ta standard ne obravnava: – ščitnikov, ki popolnoma pokrivajo priključno gred, vendar niso mehansko povezani z njo. Ker te naprave trenutno niso široko uveljavljene na trgu, naj bi bile obravnavane v prihodnji reviziji tega standarda; – mehanskih značilnosti priključnih gredi, naletnih naprav in omejevalnikov navora; – splošnih nevarnosti.

General Information

• Status: Published
• Publication Date: 30-Mar-2020
• Withdrawal Date: 30-Dec-2020
• ICS: 65.060.01 - Agricultural machines and equipment in general
• Technical Committee: CEN/TC 144 - Tractors and machinery for agriculture and forestry
• Drafting Committee: CEN/TC 144/WG 1 - General safety requirements
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 04-Dec-2019
• Due Date: 11-Jul-2019
• Completion Date: 04-Dec-2019
• Directive: 2006/42/EC - Directive 2006/42/EC of the European Parliament and of the Council of 17 May 2006 on machinery, and amending Directive 95/16/EC (recast)
• Mandate: M/396 - Mandate to CEN and Cenelec for standardisation in the field of machinery
• Ref Project: SIST EN 12965:2020 - Tractors and machinery for agriculture and forestry - Power take-off (PTO) drive shafts and their guards - Safety

Relations

• Replaces: EN 12965:2003+A2:2009 - Tractors and machinery for agriculture and forestry - Power take-off (PTO) drive shafts and their guards - Safety
• Effective Date: 11-Dec-2019

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 12965:2020
01-februar-2020
Nadomešča:
SIST EN 12965:2004+A2:2009

Traktorji ter kmetijski in gozdarski stroji - Priključne gredi in njihova zaščita -

Varnost

Tractors and machinery for agriculture and forestry - Power take-off (PTO) drive shafts

and their guards - Safety

Traktoren und Maschinen für die Land- und Forstwirtschaft - Gelenkwellen und ihre

Schutzeinrichtungen - Sicherheit

Tracteurs et matériels agricoles et forestiers - Arbres de transmission à cardans de prise

de force et leurs protecteurs - Sécurité
Ta slovenski standard je istoveten z: EN 12965:2019
ICS:
65.060.01 Kmetijski stroji in oprema na Agricultural machines and
splošno equipment in general
SIST EN 12965:2020 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN 12965:2020
---------------------- Page: 2 ----------------------
SIST EN 12965:2020
EN 12965
EUROPEAN STANDARD
NORME EUROPÉENNE
December 2019
EUROPÄISCHE NORM
ICS 65.060.01 Supersedes EN 12965:2003+A2:2009
English Version
Tractors and machinery for agriculture and forestry -
Power take-off (PTO) drive shafts and their guards - Safety

Tracteurs et matériels agricoles et forestiers - Arbres Traktoren und Maschinen für die Land- und

de transmission à cardans de prise de force et leurs Forstwirtschaft - Gelenkwellen und ihre

protecteurs - Sécurité Schutzeinrichtungen - Sicherheit
This European Standard was approved by CEN on 16 September 2019.

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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, 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: Rue de la Science 23, B-1040 Brussels

© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 12965:2019 E

worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN 12965:2020
EN 12965:2019 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

Introduction .................................................................................................................................................................... 4

1 Scope .................................................................................................................................................................... 5

2 Normative references .................................................................................................................................... 5

3 Terms and definitions ................................................................................................................................... 6

4 Safety requirements and/or measures ................................................................................................... 9

5 Verification of safety requirements and/or measures ................................................................... 14

6 Information for use ..................................................................................................................................... 23

Annex A (informative) List of significant hazards ......................................................................................... 28

Annex B (informative) Procedure of how to put the test sample together .......................................... 31

Annex ZA (informative) Relationship between this European Standard and the Essential

Requirements of EU Directive 2006/42/EC amended by Directive 2009/127/EC

aimed to be covered .................................................................................................................................... 36

Bibliography ................................................................................................................................................................. 39

---------------------- Page: 4 ----------------------
SIST EN 12965:2020
EN 12965:2019 (E)
European foreword

This document (EN 12965:2019) has been prepared by Technical Committee CEN/TC 144 “Tractors

and machinery for agriculture and forestry”, the secretariat of which is held by AFNOR.

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 2020, and conflicting national standards shall be

withdrawn at the latest by December 2020.

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 12965:2003+A2:2009.
The main changes compared to the previous edition are as follows:
— precision of the general requirements;
— addition of PTO type 4;
— precision of the requirements for the restraining system;
— addition and precision of the requirements for service and maintenance;
— addition of requirements for the locking system;
— addition of an entanglement test;

— addition of new pictogram required to highlight compatibility of guarding systems of PTO drive

shaft with tractor and machinery.

This document has been prepared under a mandate given to CEN by the European Commission and the

European Free Trade Association, and supports essential requirements of EU Directive(s).

For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this

document.

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, France, Germany, Greece, Hungary, Iceland,

Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of

North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the

United Kingdom.
---------------------- Page: 5 ----------------------
SIST EN 12965:2020
EN 12965:2019 (E)
Introduction
This document is a type C standard as defined in EN ISO 12100:2010.

The machinery concerned and the extent to which hazards, hazardous situations and events are

covered are indicated in the scope of this document.

When provisions of this type C standard are different from those which are stated in type A or B

standards, the provisions of this type C standard take precedence over the provisions of the other

standards, for machines that have been designed and built according to the provisions of this type C

standard.

Hazards that are common to agricultural machines (self-propelled, mounted, semi-mounted and

trailed) are dealt with in EN ISO 4254-1:2015. EN 12965 provides requirements for power take-off

(PTO) drive shafts in addition to those of EN ISO 4254-1.

This document is of relevance, in particular, for the following stakeholder groups representing the

market players with regard to machinery safety:
— machine manufacturers (small, medium and large enterprises);

— health and safety bodies (regulators, accident prevention organizations, market surveillance, etc.).

Others can be affected by the level of machinery safety achieved with the means of the document by the

above-mentioned stakeholder groups:
— machine users/employers (small, medium and large enterprises);

— machine users/employees (e.g. trade unions, organizations for people with special needs);

— service providers, e.g. for maintenance (small, medium and large enterprises);
— consumers (in case of machinery intended for use by consumers).

The above-mentioned stakeholder groups have been given the possibility to participate at the drafting

process of this document.
---------------------- Page: 6 ----------------------
SIST EN 12965:2020
EN 12965:2019 (E)
1 Scope

This document specifies safety requirements and their verification for the design and construction of

power take-off (PTO) drive shafts and their guards linking a tractor or self-propelled machinery to the

first fixed bearing of recipient machinery. It describes methods for the elimination or reduction of risks

that need specific requirements including such risks arising from misuse, reasonably foreseeable by the

manufacturer. It is applicable only to those PTO drive shafts and guards mechanically linked to the shaft

by at least two bearings. When used with compatible guards for power take-off (PTO) of the tractor

(master shield) or self-propelled machine and the power input connection (PIC) of the power receiving

machine, the requirements for power take-off drive shafts are complete.
NOTE 1 Fully enclosing PIC guard cones alone provide full protection.

NOTE 2 ISO 500-1 and ISO 500-2 give requirements for the guarding of tractor power take-offs (PTO) and

ISO 4254-1 gives requirements for power input connections (PIC) of power receiving machinery that are

compatible with the guarding required by this document.

In addition, it specifies the type of information on safe working practices to be provided by the

manufacturer.
This document does not deal with:

— the guards totally covering, but not mechanically linked to, the PTO drive shaft;

— the mechanical characteristics of PTO drive shafts, overrun devices and torque limiters;

— general hazards which are dealt with in EN ISO 4254-1:2015 (see introduction).
Environmental aspects have not been considered in this document.

This document is not applicable to PTO drive shafts and their guards that are manufactured before the

date of publication of this document by CEN.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments) applies.

EN 15811:2014, Agricultural machinery — Fixed guards and interlocked guards with or without guard

locking for moving transmission parts (ISO/TS 28923:2012 modified)

EN ISO 4254-1:2015, Agricultural machinery — Safety — Part 1: General requirements

(ISO 4254-1:2013)

EN ISO 5674:2009, Tractors and machinery for agriculture and forestry — Guards for power take-off

(PTO) drive-shafts — Strength and wear tests and acceptance criteria (ISO 5674:2004, corrected version

2005-07-01)

EN ISO 12100:2010, Safety of machinery — General principles for design — Risk assessment and risk

reduction (ISO 12100:2010)

EN ISO 13857:2008, Safety of machinery — Safety distances to prevent hazard zones being reached by

upper and lower limbs (ISO 13857:2008)
---------------------- Page: 7 ----------------------
SIST EN 12965:2020
EN 12965:2019 (E)

ISO 11684:1995, Tractors, machinery for agriculture and forestry, powered lawn and garden

equipment — Safety signs and hazard pictorials — General principles
ISO 1140:2012, Fibre ropes — Polyamide — 3-, 4-, 8- and 12-strand ropes

ISO 500-3:2014, Agricultural tractors — Rear-mounted power take-off types 1, 2, 3 and 4 — Part 3: Main

PTO dimensions and spline dimensions, location of PTO
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
3.1
power take-off (PTO) drive shaft

assembly consisting of two joints, telescopic members and a guard which is mechanically linked to the

shaft by at least two bearings used to transmit rotational power from the PTO of a tractor or self-

propelled machine to the PIC of an implement
Note 1 to entry: See Figure 1 - only shown as an example.
3.2
restraining system

part of the PTO drive shaft guard which prevents rotation of the guard when the PTO drive shaft rotates

Note 1 to entry: See Figure 1, key 28 - only shown as an example.
3.3
universal joint
mechanical device which can transmit torque and/or rotational motion
Note 1 to entry: See Figure 1, key 12 - only shown as an example.
3.4
wide-angle universal joint

mechanical device which can transmit torque and/or rotational motion at a constant velocity at fixed or

varying angles, generally equal or higher than 50°
Note 1 to entry: See Figure 1, key 16 - only shown as an example.
3.5
overrun device

device that permits the transmission of motion only in one direction (from the tractor towards the

recipient machinery)

Note 1 to entry: It is normally used with recipient machine having high value inertia.

3.6
torque limiter

device that cuts or limits the transmission of motion between tractor and recipient machinery, when

the torque reaches a prefixed value
---------------------- Page: 8 ----------------------
SIST EN 12965:2020
EN 12965:2019 (E)
Key
1 power take off shaft (PTO) 15 end of double yoke of outer joint
2 power-input connection (PIC) 16 wide-angle universal joint
3 PTO yoke bore 17 centre of articulation of wide-angle universal joint
4 PIC yoke bore 18 centre of outer joint
5 PTO yoke 19 guard cone
6 PIC yoke 20 wide angle guard cone
7 journal cross-assembly 21 guard bearing
8 inner yoke 22 guard tube
9 inner telescopic member 23 separate guard of wide angle universal joint
10 outer telescopic member 24 PTO drive shaft guard

11 end of inner yoke of universal joint 25 PTO drive shaft guard (in case of wide-angle PTO

drive shaft)
12 universal joint 26 PIC guard
13 PTO drive shaft, closed and extended length 27 locking system
14 double yoke 28 restraining system (as an example)
Figure 1 — Example of PTO drive shaft and guard
---------------------- Page: 9 ----------------------
SIST EN 12965:2020
EN 12965:2019 (E)
3.7
locking system

device on the PTO yoke and PIC yoke which allows locking of the PTO drive shaft mechanically to the

tractor’s PTO and to the PIC of the recipient machinery
Note 1 to entry: See Figure 1, key 27 - only shown as an example.
3.8
guard cone

guard of the inner yokes of the PTO drive shaft, integrally fixed to the guard tubes of the inner and outer

telescopic members of the PTO drive shaft
Note 1 to entry: See Figure 1, key 19 - only shown as an example.
3.9
wide-angle guard cone
guard of the wide-angle universal joint of the PTO drive shaft
Note 1 to entry: See Figure 1, key 20 – only shown as an example.
3.10
fully enclosed guard cone

guard on PIC side of the PTO drive shaft covering the universal or wide-angle universal joint, including

its locking system and the PIC of the recipient machinery, and which also includes other devices, if any

(e.g. torque limiter, overrun device)
Note 1 to entry: See Figure 2, key 4 – only shown as an example.
Key
1 implement 4 fully enclosed guard cone
2 PIC 5 clamping device on implement
3 universal joint
Figure 2 — Example of fully enclosed guard cone
---------------------- Page: 10 ----------------------
SIST EN 12965:2020
EN 12965:2019 (E)
3.11
PTO drive shaft guard

guard attached to the PTO drive shaft by bearings, designed to be able to be held stationary by a

restraining system while the shaft is rotating
Note 1 to entry: See Figure 1, keys 24 and 25 – only shown as an example.
4 Safety requirements and/or measures
4.1 General requirements

The PTO drive shafts and their guards shall comply with the safety requirements and/or protective

measures of this clause. In addition, the PTO drive shafts and their guards shall be designed according

to the principles of EN ISO 12100:2010 for hazards relevant but not significant, which are not dealt with

by this standard (e.g. thermal hazards).

Concerning the guards between the outer ends of the guard cones, unless otherwise specified in this

standard, all the apertures and safety distances shall comply with the requirements given in

EN ISO 13857:2008, Table 4.
The list of significant hazards dealt with in this standard is given in Annex A.

PTO drive shaft guards, together with PTO master shield (referred in ISO 500-1) and PIC guard, shall be

designed to prevent contact with the moving components of the PTO drive shaft when the PTO drive

shaft is operated in accordance with the operator's manual and the PTO drive shaft is connected in the

appropriate way between a tractor or self-propelled machine and a recipient machine.

The outside parts of the guard shall not turn with the PTO drive shaft.
If there is
— a torque limiter and/or an overrun device

— the use of a tool is required to lock the PIC yoke (e.g. flange yoke, clamp yoke)

on the PTO drive shaft it shall be positioned only on the PIC side of the PTO drive shaft. Relevant

marking shall be provided (see 6.2.2).

If PTO drive shaft guards have movable parts, they shall have a system to lock the parts of the PTO drive

shaft guard which can only be released by using a tool (in order to make opening an intentional action)

and which lock automatically without the use of a tool.

In the operator's manual (see 6.1), the manufacturer shall provide recommendations for proper

application and any information limiting the use of the PTO drive shaft and its guards (see 6.1, d),

including operating data and warnings against misuse. Information about requirements of the support

(e.g. form, type, position etc.) for the PTO drive shaft (see 6.1, g) and the restraining system (see 6.1, k),

shall also be provided. A safety sign illustrating the need to read the operator's manual shall be

provided on the PTO drive shaft guard (see 6.2.3).

Information on how to modify the PTO drive shaft length shall be included in the operator's manual (see

6.1 b).
4.2 Overlap on PTO side

NOTE For overlap of the PTO drive shaft guard with the power input connection (PIC) guard see

EN ISO 4254-1:2015, 6.4.1.
---------------------- Page: 11 ----------------------
SIST EN 12965:2020
EN 12965:2019 (E)
4.2.1 Universal joint

The PTO drive shaft guard cone shall cover the PTO drive shaft at least up to the end of the inner yoke of

the universal joint in order to ensure sufficient overlap between tractor master shield and PTO drive

shaft guard (Figure 1). For this purpose, the values for dimension c, distance between axis of locking

system and end of guard cone as shown in Figure 3, shall be as given in Table 1.

The dimension, c, shall be measured in straight line position of the PTO drive shaft.

Table 1 — Dimension c for PTO drive shaft
Dimensions in millimetres
PTO type c
according to ISO 500-3 max.
1 80
2 80
3 90
4 110

NOTE The overlap of minimum 50 mm of the PTO drive shaft guard with the PTO master shield results from

ISO 500-1 and ISO 500-3.
Key
1 master shield of tractor power take-off (PTO)
2 axis of locking system shield of tractor PTO

Figure 3 — Example of guarding of universal joints on PTO drive shafts on tractor side

---------------------- Page: 12 ----------------------
SIST EN 12965:2020
EN 12965:2019 (E)
4.2.2 Wide-angle universal joint

The PTO drive shaft shall be guarded in the straight-line position at least up to the end of the outer joint

of the double yoke in order to ensure sufficient overlap between tractor master shield and PTO drive

shaft guard (Figure 1). For this purpose the values for dimension c, distance between axis of locking

system and end of wide angle guard cone as shown in Figure 4, as given in Table 1 shall be met.

Dimensions in millimetres
Key
1 master shield of tractor power take-off (PTO)
2 axis of the locking system of tractor PTO

Figure 4 — Example of guarding of wide-angle universal joints on PTO drive shafts on tractor

side
4.3 Wide-angle guard cone requirements

When a wide-angle universal joint is guarded by means of a separate guard independent of the guard of

the other parts of the PTO drive shaft (Figure 1), the guarding of this wide-angle joint shall be ensured

by taking all of the following measures.

— At the maximum angular position of the rotating PTO drive shaft, as specified by the manufacturer

in the operator’s manual, the opening resulting from the angular movement shall not be more than

30 mm (see Figure 5). This requirement shall be verified by the use of a rod: if the rod can be

inserted into the opening without being in contact with the guards on both sides then the opening

is too large to be acceptable.
---------------------- Page: 13 ----------------------
SIST EN 12965:2020
EN 12965:2019 (E)

— There shall be an overlap between the wide angle guard cone and the guard cone, viewed

perpendicular to the axis of the PTO drive shaft assembly when in the maximum angular position

measured perpendicularly to the plane passing through the end of the guard cone (see Figure 5).

— The overlap between the wide angle guard cone and the guard cone shall be at least 50 mm, with

the PTO drive shaft in the straight-line position (see Figure 4). Where the opening between the

guard cone and the wide angle guard cone does not exceed 4 mm at any angular position up to the

maximum, then this 50 mm overlap may be reduced to 10 mm in the straight-line position.

Dimensions in millimetres
Key
1 maximum joint angle
2 checking gauge ∅ 30

Figure 5 — Example of guarding of wide angle universal joint at maximum joint angle

4.4 PTO drive shaft guard
4.4.1 General

The PTO drive shaft guard shall comply with the acceptance criteria according to EN ISO 5674.

The PTO drive shaft guard shall be designed so that it cannot be detached from the PTO drive shaft

without the use of a tool.

By design, it shall be possible for the user to replace the PTO drive shaft guard by following the

instructions given in the operator's manual (see 6.1, r).

The dimensions of the cone guarding the universal joints shall be such that the cone will not be

damaged by contact with the master shield of the power take-off of the tractor or self-propelled

machinery when the PTO drive shaft and its guard are at the maximum angular position given by the

---------------------- Page: 14 ----------------------
SIST EN 12965:2020
EN 12965:2019 (E)

manufacturer in the operator's manual. To verify this requirement a test shall be performed according

to 5.2.

A fully enclosed guard cone on the PIC side of the PTO drive shaft may replace the PIC guard.

The operator's manual shall include clear advice that the PTO drive shaft and its guards shall not be

used as a step (see 6.1, m).
4.4.2 Restraining system

A restraining system shall be provided (see Figure 1, key 28) to prevent all parts of the PTO drive shaft

guard rotating with the shaft. The member(s) of the restraining system shall be securely attached to the

guard and provided with a fitting that will enable them to be attached to a stationary part of the

machine without becoming detached without an intended action. The operator's manual shall include

clear advices for attaching of the restraining system (see 6.1, k) and that the restraining system shall

not be used as support of the PTO drive shaft (see 6.1, g).
4.5 Service and maintenance
4.5.1 Lubrication requirements
4.5.1.1 Lubrication access

If parts of the PTO drive shaft (e.g. universal joints, PTO drive shaft guard bearings, bearings between

the shaft and guard, telescopic members) are provided with lubricating nipples, these shall be easily

accessible for lubrication. This can be achieved by

— direct access to all the lubrication nipples through lubrication holes in the PTO drive shaft guard,

— indirect access through opening or removing parts of the guard in compliance with EN 15811.

Lubrication nipples of the PTO journal cross-assembly (Figure 1, key 7) should be located on the most

external part of one or more arms of the journal cross-assembly.

When lubrication is necessary for parts of the PTO drive shaft (e.g. telescopic members) that are not

provided with lubricating nipples, clear instructions for lubrication shall be given by the manufacturer

in the operator's manual (see 6.1, c)).
4.5.1.2 Lubrication holes

Where the lubricating operations require holes to be present in the PTO drive shaft guard, the

dimension of those holes shall be ≤ 30 mm.

Where practicable, lubrication holes shall be located on the guards in such a way that, when a hole

accommodates a nipple, also all the other holes are at the same time in alignment with the

corresponding nipple.
4.5.2 Maintenance requirements

Clear instructions about the maintenance of the PTO drive shaft and its guard shall be given in the

operator's manual (see 6.1, c)).

Where practicable, the replacement of damaged parts of the PTO drive shaft guard shall be possible

without the need for replacement of the complete PTO drive shaft guard.
---------------------- Page: 15 ----------------------
SIST EN 12965:2020
EN 12965:2019 (E)
4.6 Locking system on PTO yoke and PIC yoke
4.6.1 General

The PTO drive shaft shall include a locking system to retain it on both the tractor PTO and implement

PIC. The locking system shall be designed and constructed to prevent any unintentional unlocking

during operation.

The use of the locking system shall not require the removal or modification of the PTO master shield.

To ensure, for a locking system actuated from the outer part of the guard which does not rotate with the

PTO drive shaft, that unintentional unlocking during operation is prevented, this system

— shall require two separate and dissimilar actions (e.g. push and rotate); or

— shall require the use of both hands to unlock the locking system and the actuation device shall be

located so that PTO master shield and PIC guard provide protection against unintentional contact

with the locking system when the PTO drive shaft is operating.
4.6.2 Locking system on PTO yoke
The design of the locking system shall not cause entanglement.
The requirement has to be verified according to 5.3.

In order to be able to mount the PTO drive shaft in a convenient manner onto the tractor PTO, two

hands may be necessary for support and for proper positioning of the PTO yoke to the tractor PTO. This

can be achieved by a locking system that remains open/in the unlocked position before and during

coupling of the PTO drive shaft onto the tractor PTO, and locks automatically when the yoke is in

locking position onto the tractor PTO.

For locking systems with clamping function it is allowed to lock manually (e.g. clamp bolts that lock

manually by inserting and fixing the bolts/nuts in the yoke).
4.6.3 Locking system on PIC yoke
Except in case where

— torque limiters, overrun devices or other similar devices are used on the PIC side of the PTO drive

shaft

— the use of a tool is required to lock the PIC yoke (e.g. flange yoke, clamp yoke)

the locking system of the PIC yoke shall meet the same requirements as the locking system of the PTO

yoke.

According to 4.1, torque limiters, overrun devices, other similar devices or PIC yokes, where the use of a

tool is required to lock the PIC yoke, are only allowed on PIC side of the PTO drive shaft.

5 Verification of safety requirements and/or measures
5.1 General

Dimensions, where given, shall be verified by measurements. Guards shall be verified by functional test.

The compliance of the guard with the acceptance criteria of EN ISO 5674 shall be verified by the tests

specified in EN ISO 5674.
---------------------- Page: 16 ----------------------
SIST EN 12965:2020
EN 12965:2019 (E)
5.2 Test for guarding the universal joints including wide-angle

In order to verify if the cone guarding of the universal joints and of the wide-angle universal joints is

sufficient and will function properly in operating at different joint angles together with the PTO master

shield, the following test has to be carried out.
The power take-off drive shaft shall rotate at the speed of 540 min .

The power take-off drive shaft shall be coupled to a test fixture representing the master shield as shown

in Figure 6. For this test, PTO drive shafts with a nominal torque < 1 000 Nm or a nominal transmitted

power < 57 kW at 540 min shall be tested, with the test fixture for PTO types 1 and 2. PTO drive shafts

with a higher nominal torque or nominal transmitted power shall be tested with the test fixture for PTO

type 3 or 4. Dimensions shall be in accordance with Table 2.
---------------------- Page: 17 ----------------------
SIST EN 12965:2020
EN 12965:2019 (E)
Dimensions in millimetres
Key
1 test f
...