Hydraulic jack test standard

- Jul 11, 2018 -

1. Hydraulic jack without integrated pump

   hydraulic jack where the pump is not integrated in the jack

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1.5.1

rated load 

maximum load that a lifting equipment has been designed to carry throughout the whole stroke when operated as intended by the manufacturer and which is marked on the load plate

1.5.2

maximum possible load

maximum load that a lifting equipment complying with the requirements of this standard is able to carry due to

the setting of the load limiting device

1.6

hold to run control

control device which initiates and maintains operation of machine elements only as long as the manual control (actuator) is actuated and the manual control (actuator) automatically returns to the stop position when released !(see 3.26.3 of EN ISO 12100-1:2003)

1.7 Braking of the load supporting device

1.7.1

load pressure brake  

the braking force depends on the load and increases proportionally to the load

1.7.2

lift pad 

load carrying part of the jack    

2  Safety requirements 

2.1 Braking device 

2.1.1  General

Jacks shall be designed or equipped in a way that the load can be restrained and held. Unintentional descent shall be prevented.

This requirement may be fulfilled e.g. by   

a)self-blocking drives for manual driven jacks and self-braking drives-for power driven jacks;

b)automatic brakes;

c)non-return valves at the supporting cylinder.

2.1.2 Dimensioning 

Braking mechanisms shall be constructed in a way that the forces generated during braking can be safely restrained by the jack in any position of the load carrying device.

Braking mechanisms shall be designed in a way that the operator cannot alter their constructionally defined effect without the aid of tools.

2.2 Security against dropping 

On manual driven hydraulic and pneumatic jacks it shall be possible for the operator to regulate the lowering speed or stop the lowering at any load up to the rated load.

2.3 Speeds  

The maximum admissible average speed of descend for a jack, loaded with the rated load, is 0,15 m/s.


2.3.1 Special requirements for jacks without integrated pump  

In case of rupture of the connection between cylinder and pump a higher speed than described in 5.3 is

accepted, but the load shall then stop within a range of 100 mm.

2.4 Security against overloading

Hydraulic and pneumatic jacks with a rated load of more than 100 kg and power driven mechanical jacks with a rated load of 1 000 kg at least shall be fitted with security devices against overloading. This requirement can be fulfilled e. g. by

a)  torque limiters; 

b)  pressure relief valves; 

c)  limitation of driving energy.

These devices shall be set to the lowest possible value between 100 % and 125 % of the rated load. These devices shall be protected against unauthorized adjustment.

2.5 Transmission systems  

2.5.1  Security of guides 

Jacks shall be so equipped that rack strips, spindles or pistons cannot unintentionally loosen from their guides. This requirement shall be fulfilled in the case of cylinders if the piston is mechanically prevented from coming out of the cylinder.

2.5.2  End stops

2.5.2.1  Limitation of end positions 

Each end position of jacks shall be limited mechanically or hydraulically. The forces generated when reaching the end positions shall be absorbed safely by the jacks. It shall not be possible to put these end-stop mechanisms unintentionally out of action.

2.5.2.2  End-stop mechanism

If power-driven jacks are provided with an automatic end-stop mechanism to limit the upwards and downwards travel the movement in the opposite direction shall still be possible when the automatic mechanism has responded.

Such end-stop mechanisms may be e. g.

a)end-stop switches fulfilling the requirements of chapter 3 of EN 60947-5-1:1997 which are fitted in such a way that overshoot is taken into account, or

b)slip-clutches which are fitted to limit the working travel safely, or                                                                                    

cpressure relief valves which are fitted in hydraulic or pneumatic systems to limit the working travel.

2.5.2.3  Height adaption spindle

Load carrying devices fitted with a height adaption spindle shall be provided with an automatic operating spindle travel stop which prevents turning out.

2.5.3  Additional requirements for hydraulic jacks

2.5.3.1  Dimensioning

Cylinders, pipes and their connections which can be exposed to the maximum pressure limited by the pressure relief valve shall resist at least 2 times this pressure without showing permanent deformations. Hoses and their connections shall be dimensioned to resist a bursting pressure that is at least 3 times the set pressure of the pressure relief valve.

2.5.3.2  Pressure relief valve 

A pressure relief valve shall be fitted between the pump and the non return valve. The adjustment of the pressure relief valve only shall be possible by means of tools and it shall be  secured against unauthorized adjustment. The allowed tolerance of the adjustment is between 100 % and 125 % of the rated load. The pressure relief valve shall be adjusted to the lowest possible value.



2.5.3.3  Bleeding the hydraulic system 

In the hydraulic system means shall be provided to remove entrapped air.

2.5.3.4  Cleanliness of system medium

Every refillable hydraulic system shall have adequate means (e.g. filters) to aid the proper and continued working of the safety devices.

2.5.3.5  Refilling hydraulic fluid 

Hydraulic jacks shall be provided with refilling openings to enable refilling without the spillage of hydraulic fluid.

2.5.3.6  Fluid tank 

To prevent gas cushion in the hydraulic cylinders the fluid tank shall contain the maximum displaced volume necessary to operate the cylinder at its full stroke, + 10 % at least.

2.5.3.7  Protection against escaping hydraulic fluid

Apertures in jacks, e. g. those serving to limit the piston movement, and from which hydraulic fluid can escape during operation, shall be secured in such a way that persons cannot be injured by escaping hydraulic fluid.

2.5.3.8  Allocation of hoses and pipes 

All connecting parts the failure of which can endanger persons by escaping hydraulic fluid shall be adequately covered.

2.5.4  Additional requirements for pneumatic jacks 

2.5.4.1  Dimensioning

Cylinders, pipes and their connections which can be exposed to the maximum pressure limited by the pressure relief valve shall resist at least 2 times this pressure without showing permanent deformations. Hoses and their connections shall be dimensioned to resist a bursting pressure that is at least 3 times the adjusted pressure of the pressure relief valve.

2.5.4.2  Pressure relief valve

A pressure relief valve shall be fitted between the compressor and the non return valve. The adjustment of the pressure relief valve only shall be possible by means of tools and it shall be secured against unauthorized adjustment. The allowed tolerance of the adjustment is between 100 % and 125 % of the rated load. The pressure relief valve shall be adjusted to the lowest possible value. 

2.5.4.3  Pressure reduction 

If the pressure of compressed air supply is greater than the adjusted pressure of the pressure relief valve, a device that will reduce adequately the generated pressure automatically shall be installed. 

2.5.4.4  Cleanliness of system medium

Every pneumatic system shall have adequate means (e.g. filters) to aid the proper and continued working of the safety devices. 

2.5.4.5  Drive by exhaust fumes 

Jacks driven by exhaust fumes of internal combustion machines shall resist the special stresses (especially temperature and chemical influences).

2.6 Control devices

2.6.1  Hold to run control 

Control devices for setting power driven jacks in motion shall be of the hold-to-run type.

2.6.2  Unintentional operation

Control devices for power driven jacks shall be protected against unintentional operation.

2.6.3  Identification 

The direction of movement caused by the control device shall be identified in a durable, unambiguous and easily recognisable manner. The direction of motion can be identified by symbols or words. The identification can be attached to the control device itself or immediately alongside it.

2.6.4  Obviousness

For power driven jacks and - wherever possible for manual driven jacks - the direction of operation of the controls and of the movements they cause shall be arranged in an obvious relationship to one another. Preferably this requirement may be fulfilled, e. g. for raising and lowering movements:

a)  in the case of buttons, if the button for the raising movement is arranged above the button for the lowering movement, or if the button for the raising movement is arranged on the right and the button for the lowering movement on the left (see figure 7),

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b)  in the case of foot-control, if the control device for the raising movement is on the right and for the lowering movement on the left (see figure 8)

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c)  in the case of horizontal levers,if the upwards movement of the lever generates the raising movement and the downwards movement of the lever the lowering movement (see figure 11),

 if the movement of the lever to the right generates the raising movement and the movement of the lever to the left the lowering movement (see figure 9)


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d)  in the case of vertical levers, if the movement of the lever towards the human body generates the raising movement and the movement of the lever away from the human body the lowering movement (see figure10), 


Figure 10 — Movement of vertical levers

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  e)  in the case of wheels, if turning the wheel to the right generates the raising movement and turning it to the left generates the lowering movement (see figure 11).

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2.6.5  Visibility

The operator´s position shall give the operator a clear view of the hazardous parts of the jack and its load at all times through its vertical movement. If the operator´s position is not determined by the manufacturer see 7.


2.6.6  Control devices of manually operated jacks

Control devices of manually operated jacks shall be equipped in such a way that 

a)winding handles, levers, or wheels cannot turn back under load more than 15 cm, measured at the greatest radius of the control (reversal security). Reversal security shall not be necessary for hand-wheels if these take the form of complete smooth disc wheels shut and without any other handles;

b)  the direction of rotation of winding handles remains the same regardless of gearing, and

c)  removable winding handles, levers, and hand-wheels shall be secured against slipping and unintentional removal from the drive shaft.

Requirement c) may be fulfilled e.g. 

 if securing mechanisms such as snap-in latches or locking springs are fitted or for winding handles or levers up to a length of 250 mm if they can be pushed into their shafts at least to one-fifth of their own lengths (see figure 12).

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2.6.7  External power supply

If an external power supply is used there shall be means to disconnect the power and to secure them against unallowed re-connection.

2.7 Combined manual and power-operated jacks

Jacks capable both of being manually operated and driven by power shall be designed in such a way that no-one can be put in danger by movements of the manual controls when the power drive is on. 

This requirement may be fulfilled if  

a)the manual drive is automatically uncoupled when the power drive is on, or

b)power and manual operation are covered by an interconnected locking mechanism, or

c)completely smooth discs without any other handles are fitted. 

2.8 Requirements for safety mechanisms

2.8.1  Adjustments 

The braking device mentioned in 5.1, the security device against overloading mentioned in 5.4 and the reversal security device mentioned in 5.6.6 shall be designed and constructed in such a way that adjustment is impossible without the aid of tools.

This requirement is e.g. fulfilled in the case of jacks with removable winding handles or levers if a reversal and a braking device are integrated parts of the jack. 

This requirement is fulfilled on safety devices with safety catches in case the safety catch cannot be brought out of operation, e.g. by a special styling or by the use of covers.

2.8.2  Materials

Ratchet pawls, fixing wheels, and similar locking mechanisms shall be so constructed that neither a breakage after a period of time or through brittleness need be feared nor plastic deformations occur by reason of the toughness of the material used. 

2.8.3  Effects of weather and dirt 

The safety devices on jacks shall be constructed and fitted in such a way that they cannot be put out of action by the effects of the weather or by dirt when used as intended by the manufacturer.

This requirement may be fulfilled e. g. by

a)  encapsulating; 

b)  choice of material; 

c)  design. 

5.8.4  Breakage of springs 

Failure of a spring shall not make safety devices inoperative.

This requirement may be met e.g. by 

a)the installation of a number of springs if, in the event of one spring failing, the remaining springs provide sufficient retaining power;

the use of compression springs with both ends fixed or by selection of springs such that the wire diameter is greater than the distance between the coils, hence preventing the two pieces from winding into each other in the event of a breakage. Furthermore, compression springs shall be guided to prevent them buckling or the end Furthermore, compression springs shall be guided to prevent them buckling or the ends becoming displaced during use

b) becoming displaced during use. 

NOTE  In the case of springs that are under static pressure, e. g. in slip clutches, it is assumed that no spring breakage will occur. 

2.9 Lift pad 

The lift pad shall have a rough surface or be designed in such a way to counteract any tendency of the load to slip off.

By design the projection of the lift pad shall always be within the tipping lines of the jack. This requirement does not apply to claws at the side of the jack.

2.10 Structural design 

 All manual operated mechanical jacks defined within the scope of this standard shall be designed to withstand at least 150 % of the rated load in all critical modes at ambient temperature without showing permanent deformation of any part. For all other jacks the same requirement is valid with the exception that 150 % of the maximum possible load shall be taken into consideration.

 2.11 Climatic conditions 

The jacks shall be designed to work at rated load in a temperature range of -20 °C to +50 °C.

NOTE  If in other applicable standards there are more restricted temperature ranges, the manufacturer needs to take this into account when negotiating with the supplier of the relevant components.

2.12 Hot surfaces

If any parts of the driving system (e. g. hydraulic tanks, motors etc.) are designed to operate at a high temperature of above 55 °C, these parts shall be protected or positioned to avoid contact of persons.

2.17 Provisions for maintenance

2.17.1 Accessibility

All bearing parts and all moving parts that require regular inspection shall be easily accessible.

2.17.2 Adjustment

All screws, pins, bolts and similar parts shall have means for preventing self loosening. They shall allow adjustment if necessary.

2.21 Special requirements for jacks without integrated pump 

In case of rupture of the connection between cylinder and pump a higher speed than described in 5.3 is accepted, but the load shall then stop within a range of 100 mm.

3  Verification 

 3.1  General

3.1.1  Tests 

The checks and tests to ensure that the jack complies with this standard shall consist of:

a)  design check (see 6.1.2); 

b)  manufacturing check (see 6.1.3); 

c)  visual verification (see 6.1.4); 

d)  practical tests (see 6.1.5); 

e)  electrical tests (see 6.1.6); 

f)  final inspection before despatch (see 6.2). 

A type verification shall consist of 6.1.2, 6.1.3, 6.1.4, 6.1.5 and 6.1.6.

An individual machine verification shall consist of 6.2. 

The result of the examinations and tests shall be recorded in a dated and signed report with the name and position of the person(s) who has signed it and the name and address of the company or organisation that made the tests. 

3.1.2  Design check 

The design check shall verify that the requirements of this standard are fulfilled. It shall also be checked that: 

a)the drawings are available and complete and give the main dimensions of the jack;

b)there is a description of the jack with the necessary information about it's capabilities;

c)information is given concerning the materials and proprietary components used;

d)diagrams of the hydraulic, pneumatic and electrical circuits are available and complete;

e)instructions covering installation, commissioning, operating, maintenance and dismantling are available and complete. The documents shall give all the necessary information to enable the check of the calculation requirements.

3.1.3  Manufacturing check

The manufacturing check shall verify that: 

a)the jack has been manufactured in accordance with the checked documents and drawings;

b)  test certificates are available e. g. for wire ropes, chains and hoses if used.  

6.1.4  Visual verification   

It shall be visually verified that:

7.2 a)all the marking specified in 7.2 have been affixed to the jack

      b)  the jack is in accordance with all the documentation provided by the manufacturer;

b)the means of transport and installation conform to 5.16;

c)there is no evidence of external leakage of hydraulic fluid;

d)the instruction handbook described in 7.1 is provided.

3.1.5  Practical tests  

Practical tests as detailed in annex B.1 for type testing and annex B.2 for individual machine final verification, shall be carried out to verify that: 

a)  the jack is stable; 

b)  the jack is structurally sound; 

c)  all the functions of the jack can be safely and correctly carried out.

3.2 Individual final verification before despatch

3.2.1  Before despatch of each jack, a verification shall show that the jack satisfies the safety requirements of this standard. The results of this verification shall be recorded. 

3.2.2  If a type test for the jack model has been carried out, then it is only necessary to functionally test each individual jack without load throughout its full travel; each individual    hydraulic/pneumatic jack with rated load throughout its full travel and also the correct functioning of the pressure relief valve; on manual driven mechanical jacks at least 10 % of the series with the rated load throughout its full travel; each individual power driven mechanical jack with 110 % of the rated load throughout its full travel.  

3.2.3  Where the jack has not been type tested, the final verification shall consist of tests and verifications according to 6.1.2, 6.1.3, 6.1.4, 6.1.5 and 6.1.6.

4  Information for use

4.1 Instruction for use and instruction handbook 

An operating and instruction handbook complying with !6.5 of EN ISO 12100-2:2003" shall be delivered by the manufacturer with each jack

4.1.1  General

The instruction handbook shall clearly describe the type and scope of the jack and state the standard to which it conforms. Further it shall include at least the rules according to 7.1.2 to be followed by the user. Further the following restrictions given in this standard and hints necessary according to this standard shall be contained: 

a)  Limitation of range of application as 

operation in severe conditions (e.g. extreme climates, freezer application, strong magnetic fields);

operation subject to special rules (e.g. potentially explosive atmospheres, mines);  supply by electrical networks where the tolerances in voltage, frequency etc. differ from those in the public supplies; 

 life time of the jack; 

prohibition of lifting of persons. 

b)  static electric problems; 

c)  handling of loads, the nature of which could lead to dangerous situations (e.g. molten metal, acids, radiating materials, especially brittle loads); 

d)  hazards occurring during decommissioning;

e)  wind pressure in and out of use;

f)  direct contact with foodstuffs; 

g)  limits of use in relation to the actual IP-level;

h)  limits of use in relation to the actual IK-level;

i)  operation on sea ships;

j)  hint to spillage of oil;

k)  hint that in case the generated efforts exceed the values given in Annex C, the efforts shall be lowered by additional persons; 

l)  the operating method to be followed in the event of accident or breakdown; if a blockage is likely to occur, the operating method to be followed so as to enable the equipment to be safely unblocked 

m) the specifications of the spare parts to be used, when these affect the health and safety of operators.

4.1.2  Rules for operating 

The rules for operating shall include:

 The user shall work in accordance with the instruction handbook;

 It is necessary that the operator can watch the lifting device and the load during all movements; 

 It is not allowed to work under the raised load until it is secured by suitable means;

4.1.3  Maintenance and repair 

The rules for maintenance and repair shall include:

 When refilling the hydraulic system the characteristics of the hydraulic fluid used in the jack and the level of the hydraulic fluid as it is given by the manufacturer shall be observed; 

 Information about hoses; 

 Need to check the state of the markings and that the markings remain as the initial one; 

 4.2 Minimum marking

Every jack shall be marked permanently and legibly on a non removable part of the device with the following information: !the business name and full address of the manufacturer and, where applicable, his authorized representative;

 design of series or type; 

product code and designation of the machinery;

 Serial number or batch code; 

 !the year of construction, that is the year in which the manufacturing process is completed;"

 Rated load;

 Where the rated load depends on the configuration of the jack the rated loads shall be shown for each configuration on a load plate, preferably in diagrammatic form or by means of tables;

 All necessary hydraulic supply information if an external hydraulic power supply is used;

Annex B  

Test procedures

B.1  Practical tests for Type Testing Procedure

B.1.1 General

a)  Check the correct operation of the controls; 

b)  Check that the safety devices are functioning as intended;

c)  Operate the unloaded jack through one complete cycle;

d)  Place the rated load distributed as specified by the manufacturer on the jack and operate it through one complete cycle. Record the maximum operating pressure in steady state for hydraulic and pneumatic drives; 

e)  Record the time taken to fully lower the jack while carrying the rated load. The average speed shall not exceed 0,15 m/s; 

f)  Leave the jack, still carrying the rated load, fully raised for 10 min. Measure and record the vertical descend of the jack in this time. Generally this descend shall not exceed 2 mm. On hydraulic jacks using mechanical linkages (e.g. trolley jacks) a maximum descend of 5 mm is admissible; 

g)  static overload 

Lift the lift pad without the load to half stroke position. Expose the jack positioned vertically to a vertical load of 150 % of the rated load in case of manual operated mechanical jacks 150 % of the maximum possible load in all other cases. Under this condition (height adaptation spindle turned to the highest position) it shall be possible to carry the load, to sustain it for a period of 15 minutes and to lower it. After this test the tested jack shall be dismantled to prove that no permanent deformation has occurred in any part. 

h)  dynamic overload 

For the following test the pressure relief valve of hydraulic and pneumatic jacks shall be neutralized. Position the jack vertically and apply a vertical load of 125 % of the rated load in case of manual operated mechanical jacks 125 % of the maximum possible load in all other cases. The jack shall then be capable of lifting and lowering this load through its entire stroke as for intended use. After this test the tested jack shall be dismantled to prove that no permanent Deformation has occurred in any part.

i)  Manual forces;

Manual forces shall be measured according to Annex C.

j)  Over travel device;

Operate the jack without load 10 times to the upper position until the over travel device is operating. No permanent deformation of any part is permissible.  

k)  Test the load limiting device; 

l)  Check satisfactory operation of braking or holding devices according to the design, where fitted. 

B.1.2 Additional tests for hydraulic jacks 

All types of hydraulic jacks can exist in principle also as pneumatic jack. For the pneumatic jacks the same additional tests as stated in B.1.2 shall be performed.  

a)  Static test

Store the jack at an ambient temperature of + (23 + 5) °C for at least 12 hours. Then expose it to its maximum possible load at nominal full stroke specified by the manufacturer, for at least 30 minutes. Within that time, generally a maximum lift pad lowering movement of 2 mm is admissible. On hydraulic jacks using mechanical linkages (e.g. trolley jacks) a maximum descend of 5 mm is admissible. The measurement is to start 5 minutes after applying the load. 

b)  Pressure relief valve 

Expose the jack to a load according to the set pressure of the pressure relief valve plus 5 %. Then the jack shall not be capable to lift this load but shall be able to sustain it.

Then, pump the jack up to its full stroke without the load until the pressure relief valve operates. This pressure shall be recorded and shall not exceed 125 % of the rated load. This test shall be performed 10 times in a row. No failure of the pressure relief valve is admissible.

On devices with hydraulic limitation of the end position the test shall be performed at 2/3 of the full stroke. At this test the piston shall be blocked by application of an external force. On devices with telescopic cylinder the stage with the smallest diameter shall be partially extended. 

c)  Safety device against pipe damage

On jacks a breaking of the connection between cylinder and pump (hose, pipe) shall be simulated. The non-return valve on the jack shall respond. The load shall not come down more than 100 mm. It shall not be possible to reoperate the jack by the normal controls until proper measures are taken. 

B.1.3 Additional tests for hydraulic jacks for road vehicles 

In addition to the tests according to B.1.1 and B.1.2 the following tests shall be performed:

a)  Behaviour at temperatures 

Store the jack at + (50 + 5) °C for a min. period of 12 h. No visible leakage is admissible during this test. Then store the jack at - (20 + 2) °C for a min. period of 12 h. No visible leakage is admissible during this test. 

The jack shall be placed in its operating position on the test rig immediately after each of the above conditioning and shall be able to lift the rated load at each of the above temperatures through the full stroke specified by the manufacturer.

Use the test rig as shown in figure B.1. 

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 Lever A is intended to simulate the travel of the axle to be lifted. Dimension h shall be adjusted in the way that lever A is horizontal when the jack is in the middle of its stroke.

The area on lever A where the head of the jack is applied shall have a hardness of at least 285 HB and a surface roughness of Ra 6,3 µm, to avoid slipping off.

b)Strength test 

 The jack shall be capable to lift, to stop and to lower the rated load 50 times over the full stroke at a temperature of (23 + 5) °C, with the height adaptation spindle turned to the lowest position. Between each lift, there shall be a pause of 5 minutes.

Lubrication after 10 strokes is allowed.

 After maintaining the rated load for 2 minutes, the height shall be checked after the last lift.

This height shall be such that it proves that the nominal stroke quoted by the manufacturer is achieved with an acceptable tolerance of -2 mm. 

 c)  Stability test 

Hydraulic jacks shall be placed on a 6° plate as figure B.2 and a load equivalent to 125 % of its rated load applied in the middle of the lift pad at 80 % of its maximum stroke, spindle not extended, for a period of 5 minutes. The jack shall show no permanent deformation and no failure of any part. 

Further it shall be verified by calculation that the vertically projected area of the lift pad is within the tipping lines when the jack is inclined by 6° in the worst condition. 

 

 

 



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