SAFE JACKING OF TRACTORS - Occupational Health & Safety Practitioner Reading January 2007
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Occupational Health & Safety
Practitioner
Reading
SAFE JACKING OF TRACTORS
January 2007
®Contents
OVERV IEW .......................................................................................................................1
SECTION 1: INTRODUCTION ........................................................................................2
SECTION 2: EQUIPMENT REQUIREMENTS ................................................................3
SECTION 3: CONSIDERATIONS PRIOR TO JACKING ................................................9
SECTION 4: JACKING PROCEDURE ..........................................................................11
SUMMA RY ......................................................................................................................14
REFERENCES A ND FURTHER REA DING ...................................................................15
Published by WorkSafe,
Department of Consumer and
Employment Protection,
PO Box 294, WEST PERTH WA 6872.
Tel: Toll Free 1300 307 877.
Email: institute@worksafe.wa.gov.au
The SafetyLine Institute material has been prepared
and published as part of Western Australia’s
contribution to the National Occupational Health and
® Safety Skills Development Action Plan.
www.worksafe.wa.gov.au/institute
© 2007 State of Western Australia. All rights reserved.
Details of copyright conditions are provided at the SafetyLine Institute website.
Before using this publication note should be taken of the Disclaimer, which is published at the
SafetyLine Institute website.READING – SAFE JACKING OF TRACTORS
OVERVIEW
There is a w ide range of large equipment being used in the rural
industry that could cause serious injury or death if not correctly
maintained and operated. This reading covers the correct
procedure for the jacking of tractors and other large farm
equipment w hen tyres need to be changed or general w heel
maintenance w ork needs to be carried out.
Objectives
After reading this information you should be able to detail the
correct method of jacking farm equipment in the w orkplace.
Author
Alan Rolls
Certificate Occ. Health &
Safety
JANUARY 2007 SAFETYLINE INSTITUTE PAGE 1READING – SAFE JACKING OF TRACTORS
Section 1: INTRODUCTION
1.1 Tractors should be jacked in a
workshop using special
KEY POINT
equipment
Those without adequate
Ideally, tractors and other large farm equipment should on-site experience of
be jacked in a w orkshop on a solid, concrete floor, jacking large pieces of
equipment should not
using purpose built lifting equipment in a safe and attempt it.
controlled environment. This is especially necessary
where larger tractors are involved.
In the absence of adequate on-site experience of jacking large
pieces of equipment, it is necessary to engage the services of
trained and experienced tyre fitters or maintenance personnel w ho
are properly equipped to carry out this type w ork.
1.2 Safe procedures for jacking
vehicles in the field
It is recognised that ideal w orkshop conditions w ill not alw ays be
available and vehicles w ill need to be jacked in the field. Jacking
vehicles in the field can be safely achieved providing adequate
precautions are taken. These precautions include the use of
appropriate equipment, experienced operators and limiting the
number of w heels removed at any one time to one. Removing
double w heels from one end of an axle is considered the same as
removing one w heel.
PAGE 2 SAFETYLINE INSTITUTE JANUARY 2007READING – SAFE JACKING OF TRACTORS
In addition to jacks, a secondary support system consisting of
vehicle stands or blocks of timber should be used.
While this approach may not be the only w ay that jacking can be
carried out in the field, the use of this type of procedure should
ensure that the risk of injury or death associated w ith jacking is
minimised.
Section 2: EQUIPMENT REQUIREMENTS
2.1 Use and maintain the correct
equipment
It is important to use the correct equipment for the job and to
ensure that the equipment is properly maintained and stored
correctly when not in use.
The follow ing equipment is necessary for the safe jacking of
tractors and other large farm equipment.
2.2 Vehicle jacks
Jacks should comply, as a minimum, w ith the requirements of
Australia/New Zealand Standard 2693:2003/A mdt 1:2004 Vehicle
Jacks. They should be marked as complying w ith the Standard
and have instructions on their safe use and maintenance, safe
working loads and contact details of the manufacturer or Australian
distributor.
Jack Safe Working Loads
The jack used must be capable of lifting more than half the w eight
of the tractor. Because of this, it is also important to know the
weight of the tractor.
When tw o jacks are used simultaneously to raise KEY POINT
a load, both jacks must be capable of lifting in
The jack must be able to
excess of half the load. Great care must be safely lift over half the
taken to ensure that both jacks are raised at the weight of the tractor.
same rate, otherw ise one jack w ill take a greater
proportion of the w eight.
JANUARY 2007 SAFETYLINE INSTITUTE PAGE 3READING – SAFE JACKING OF TRACTORS
T
y
p
i
c
a
l
V
e
h
Typical Vehicle Jacks
Bottle jacks should have a heavy, broad base for stability in the
raised position. They must be low ered after use, stored in an
upright position, covered (to prevent moisture or dirt affecting the
hydraulic seal) and correctly maintained.
KEY POINT
Jacking equipment that incorporates a remote,
hydraulic pumping mechanis m should not be used To prevent collapse, jacks
unless it is established that it is fitted w ith a flow- with a remote, hydraulic
restricting device that acts to restrict the flow of pumping mechanism must
be fitted with a device that
hydraulic fluid out of the jack. This is critical to prevent acts to restrict the flow of
collapse of the jack in the event of a hydraulic hose hydraulic fluid out of the
failure. jack.
2.3 Vehicle stands
Vehicle stands should comply w ith Australian Standard 2538-2004
Vehicle Support Stands.
The correct capacity vehicle stand for the particular load to be
supported must be used, or one w ith a greater capacity.
It is important to ensure that only vertical forces are imposed on
vehicle stands because vehicle stands are only tested KEY POINT
at a 5-degree angle for their ability to hold loads and
remain stable. They may collapse if the load is applied Never use a vehicle stand
at an angle greater than 5 degrees from the vertical. unless the force on it is
vertical, because it will
collapse.
PAGE 4 SAFETYLINE INSTITUTE JANUARY 2007READING – SAFE JACKING OF TRACTORS JANUARY 2007 SAFETYLINE INSTITUTE PAGE 5
READING – SAFE JACKING OF TRACTORS
2.4 Timber blocks
Timber blocks must be hardw ood (jarrah, karri or similar) and free
of decay, gum veins or termite galleries.
Knots, knot holes and borer holes must not exceed 12 millimetres
(half an inch) in diameter for the blocks to be considered as
suitable for supporting heavy machinery.
The blocks must be at least 200 millimetres (8 inches) w ide and at
least 100 millimetres (4 inches) high, w ith square edges so that
they form a smooth, even, flat surface when placed on top of each
other to form a support for the jack or the vehicle stand. Timber
which has become w arped must not be used for jacking.
The timber blocks forming the base must be bolted together
through the face (the w idest dimension) so they stand "on edge"
(ie, on the side w ith the narrow est dimension) to obtain the
maximum strength from the blocks. The reason the blocks should
be bolted together is to avoid the possibility of soil being forced
betw een the blocks during jacking, thereby separating them and
rendering them unstable. The bolts used to join the timber blocks
together should be a minimum of 16 millimetres (5/8 inch) in
diameter.
The space betw een the differential and the tyre may not be
sufficient to allow wide blocks of timber to be used, so
it may be necessary to use one long sleeper to provide KEY POINT
the necessary surface area. How ever, care should be
The timber blocks used
taken w hen selecting the sleeper to ensure that it must not be used for any
provides sufficient stability across the w idth of the other purpose.
sleeper and there is no likelihood of the sleeper
splitting under load.
Handles of rope or steel rod (preferably steel rod) should be fitted
to make it easier to move and carry the blocks to reduce the risk of
manual handling injuries.
A stock of jacking timber is as much a tool as any other piece of
equipment used for maintenance. This jacking timber should
therefore be stored undercover, well supported and off the ground
to protect against termite attack.
The blocks should also be oiled to resist rot, w eathering and
premature w arping, w hich will render them unfit for use.
PAGE 6 SAFETYLINE INSTITUTE JANUARY 2007READING – SAFE JACKING OF TRACTORS
2.5 Type of soil determines timber
block size
The type of soil on w hich tractor jacking is to take place w ill
determine the size of the timber raft against the ground. Australian
Standard 2550 Part 1, 2002/A mdt 1-2004, Cranes - Safe Use,
General Requirements, provides a guide:
Safe Bearing Pressure for Crane Outriggers
tonnes tons
per per
Soil Description kPa
square square
metre foot
Hard clay 700 70 6.5
Medium dense to 800 80 7.5
dense/coarse sand
Loose medium and coarse 500 50 4.7
sand/dense fine sand
Loose fine sand 400 40 3.7
Stiff clay 350 35 3.3
Soft clay 80 8 0.7
Loose fill Not Not rated Not
rated rated
According to the above table, loose, fine sand w ill generally
support a pressure of up to 40 tonnes per square metre (3.7 tons
per square foot). This means that four sleeper blocks, 100
millimetres (4 inches) thick and 375 millimetres (15 inches) in
length, bolted together on edge, should support about six tonnes
while five sleeper blocks, 450 millimetres (18 inches) in length,
bolted together on edge, should support a load of about nine
tonnes. Five blocks of 525 millimetres (21 inches) in loose, fine
sand should support ten tonnes.
JANUARY 2007 SAFETYLINE INSTITUTE PAGE 7READING – SAFE JACKING OF TRACTORS
Where stiff clay is encountered, the safe bearing pressure is
reduced to 35 tonnes per square metre and w here soft clay is
involved, the safe bearing pressure is further reduced to 8 tonnes
per square metre, so larger sized timber w ould be necessary to
support a given load.
Other soil types such as gravels, coarse sands, hard clays and
combinations of these soil types should support in excess of 40
tonnes per square metre, as detailed in the Standard.
2.6 Wheel chocks
Wheel chocks, preferably blocks of timber, must be available for
the front and rear of both wheels on the side opposite to the one
being jacked. They must be sufficiently large and stable to prevent
the w heels moving dur ing jacking. If possible, do not use
improvised chocks, such as rocks, when jacking because they
tend to roll aw ay as the tractor is jacked.
2.7 Other equipment
Properly designed w heel spanners, or preferably torque multiplying
wrenches, designed to minimise the manual force required to
loosen and tighten w heel nuts should be used to avoid the
possibility of a manual handling injury or an injury from the spanner
slipping from the nut.
A means of communication must be available w hen the w ork is
being carried out in a remote location w here other people at the
workplace are not in visual or audible contact.
To reduce the risk of a manual handling injury, a means of
supporting and handling the tractor w heel during and after removal
from the tractor should be available. For larger w heels this could
be a supporting frame comprising a pivoted handle, a stationary
tripod or frame w ith block and tackle, or a hydraulic lifting device.
It is obviously not practical for all this equipment to be KEY POINT
carried on the tractor. How ever, tractor jacking w ithout
it is dangerous and should not be attempted. It is very dangerous to jack
a tractor without having the
Therefore, it w ill alw ays be necessary to take the time right equipment.
to get the equipment before any attempt is made to
jack the tractor and carry out maintenance in the field.
PAGE 8 SAFETYLINE INSTITUTE JANUARY 2007READING – SAFE JACKING OF TRACTORS
Section 3: CONSIDERATIONS PRIOR TO JACKING
3.1 Positioning of the tractor
Where possible, the tractor should be moved to a flat, level and
firm surface before any attempt is made to jack it off the ground to
change a tyre. Repairs to split transmission components, or any
other maintenance w ork that requires the machine to be jacked,
should be carried out on a flat, solid concrete floor. This may
necessitate the tractor being tow ed to the w orkshop before starting
repairs.
In the field, it may be necessary to drive on a flat tyre or have the
tractor towed to a suitable location before any jacking is attempted.
If it is thought that a tyre may have been punctured, immediately
move the tractor to the best possible position for jacking before the
tyre deflates completely.
Regardless of the circumstances, the tractor should not be jacked
on ground w ith a slope greater than 5 degrees (or 1 in 12). If
repairs are to be carried out on steep ground, suitable lifting
equipment, such as a crane w ith appropriate safe working load
designations, must be used. Properly trained and equipped tyre
fitters or maintenance personnel may need to be employed to
carry out repairs in these circumstances.
3.2 Safe work procedures
If circumstances dictate that the tractor must be jacked up in the
field, the follow ing points should be observed:
• The tractor must not be jacked up w here the ground has a
slope of more than 5 degrees. It may be necessary to dig
under the w heels on the high side of the slope to reduce the
gradient.
• All implements must be removed from the draw bar of the
tractor before jacking commences.
• The w heel to be removed must be located on the high side of
the slope to minimise any risk of injury should the tractor move.
It is also important to exclude people from the low side of the
tractor during jacking.
JANUARY 2007 SAFETYLINE INSTITUTE PAGE 9READING – SAFE JACKING OF TRACTORS
• Only one w heel should be removed at a time w hen a jacking
operation is carried out in the field. For example, sometimes it
is necessary to rotate the w heels to reverse the tyre tread.
Because this operation requires both w heels to be removed for
a short period of time, the operation should not be carried out
in the field.
• Jacks should be operated w ith the load acting dow n through
the centre of the jack. When jacks or vehicle stands are
required to support the w eight of a tractor, any lateral forces
generated by the w eight not acting vertically dow nward may
make the jacks or vehicle stands unstable.
• Vehicles w ith articulated steering pose special problems w hen
being jacked. Unless the articulated joint is rendered rigid, the
vehicle has, w hen raised off the ground, the potential to slip off
the jack. The remedy is to securely w edge, or otherw is e
secure, the articulated joint so that the vehicle w ill not bend
when jacked.
3.3 Jacking points
In the first instance, refer to the manufacturer's instructions
regarding jacking procedure and the location of appropriate jacking
points.
Where no such instructions are available, seek advice from the
supplier, manufacturer or maintenance personnel w ith experience
in w orking on your particular brand of equipment.
KEY POINT
Legislation requires the manufacturer of a piece of
plant to provide instruction for the safe jacking of their For stability, ensure the
equipment. This instruction should include w here to jacking points are as far
position a jack. from the centre of the
tractor as possible.
Where jacking points are not readily identified, choose
the low est possible point so that timber blocks do not
have to be used to raise the jack excessively high. This w ill reduce
the possibility of the jack becoming unstable w hen under load or in
the raised position.
Never jack under the central differential housing using a single
jack. Alw ays use jacking points as far from the centre of the tractor
as possible to minimise the tractor becoming unstable.
PAGE 10 SAFETYLINE INSTITUTE JANUARY 2007READING – SAFE JACKING OF TRACTORS
Section 4: JACKING PROCEDURE
4.1 Ensure tractor and ground are
stable
Having positioned the tractor and identified the appropriate jacking
points as discussed, the ground beneath the jacking points should
be cleared of any rocks and tree roots. The ground should be
smoothed and levelled to allow w ooden blocks to be placed under
the jacking point. This w ill provide a firm base on w hich to place
the jack.
All w heels that remain on the ground should be chocked on both
sides w ith large blocks of timber to prevent the tractor from rolling
forward or backw ard when jacking is commenced.
Tractor brakes should be applied and the tractor should be in gear
(or "park" w here automatic transmissions are involved) w ith
ignition sw itches off.
4.2 Use blocks
As previously detailed, if a large tractor is being jacked or the
ground on w hich the tractor is being jacked is soft, such as in a
new ly ploughed field, blocks of an appropriate size should be
placed on edge, side by side, bolted together and centrally placed
under the jacking point.
The bottom layer of blocks should be positioned w ith the ends of
the blocks pointing tow ards the inside of the tyre. Additional blocks
should then be placed centrally on the low er blocks, flat and at
right angles, spanning all of the low er blocks. The jack should then
be placed centrally on the upper blocks.
If the draw bar of the tractor is being used as the jacking point and
there is insufficient space to place the tw o layers of blocks, either
use a compressor to temporarily inflate the tyre or dig out the
ground under the jacking point. This w ill make the necessary
space available rather than choosing a higher jacking point. This
will ensure the jack remains as stable as possible throughout the
jacking procedure.
JANUARY 2007 SAFETYLINE INSTITUTE PAGE 11READING – SAFE JACKING OF TRACTORS
Advice should be sought from the manufacturer, or their agents, to
determine w hether or not it is safe to use the drawbar as a jacking
point. The draw bar should only be used if it is far enough aw ay
from the centre of the tractor to ensure stability during jacking.
If additional blocks are necessary to raise the height of the jack,
then they should be placed on the flat and at right angles to the
low er layer. The additional blocks need not be bolted together but
they should cover the entire area of the base, w ith the top blocks
placed at right angles to those in the second layer and spanning all
of the blocks.
4.3 Use vehicle stands
Never get under a tractor or any other vehicle that is supported
only by a jack. Alw ays install a vehicle stand and ensure at least
half the w eight is carried by the stand before venturing under the
tractor.
If vehicle stands are to be used to support the tractor in the raised
position, blocks of timber should be used under each
KEY POINT
vehicle stand to provide a solid base. Clear and level
the ground beneath the point on the tractor w here the Never get under a tractor
vehicle stands are intended to be placed. Position or any other vehicle that is
additional blocks of timber so as to form a base for the supported only by a jack.
vehicle stands.
Place the vehicle stands on the blocks, ensure that they are
vertical and stable and that the engagement heads are fully in
contact w ith the support point, or w ill be, w hen the tractor is jacked
to the necessary height.
PAGE 12 SAFETYLINE INSTITUTE JANUARY 2007READING – SAFE JACKING OF TRACTORS
4.4 Stacking the timber blocks
If blocks of timber are to be used in place of vehicle stands to
support the tractor in the raised position, the first layer should be
stacked and bolted (as w ith the blocks under a jack) to form a
base. Subsequent layers of timber blocks should be stacked in a
criss-cross fashion (pigsty stacking) to ensure that the timber stack
is as stable as possible in all directions and capable of supporting
the tractor in the raised position.
4.5 Raising the tractor
Tw o jacks may be used to progressively raise the tractor to allow
the jacks to be straightened during the jacking procedure.
How ever, this should only be done w here the tractor does not
become unstable w hen switching the support from one jack to the
other. If stability is adversely affected, then one jack should be
used and the tractor supported by blocks or vehicle stands while
the one jack is adjusted.
Wheel nuts should be loosened before the w heel is lifted from the
ground, to avoid causing the tractor to move and possibly fall.
The tractor should then be jacked slow ly from a safe position,
using an extension bar for the jack handle, so as to prevent injury
should the tractor fall. The movement of the tractor should be
checked for signs of instability during jacking. If the tractor tends to
move off the jack during the jacking procedure, let the jack dow n,
re-position the blocks and jack to improve stability and begin
jacking again.
JANUARY 2007 SAFETYLINE INSTITUTE PAGE 13READING – SAFE JACKING OF TRACTORS
Raise the vehicle stands or the blocks of timber progressively as
the tractor is jacked higher. When the tractor is at the required
height, raise the vehicle stands or blocks of timber as high as
possible and carefully low er the tractor onto the secondary
supports.
Never leave a tractor or any other vehicle supported on a hydraulic
jack. Alw ays install a vehicle stand or w ooden blocks and ensure
they can support the w eight.
KEY POINT
Never jack more than one w heel off the ground at a time Never jack more than one
in the field. If both w heels must be removed for any wheel off the ground at a
time in the field, only in the
reason, carry out the procedure in the w orkshop on a workshop.
level, solid concrete floor.
4.6 Lower tractor and remove
equipment
Carry out the necessary repairs and replace the w heel onto the
wheel hub. Tighten opposite pairs of w heel nuts progressively until
the w heel is firmly against the hub. Raise the tractor off the
secondary supports and progressively low er the supports and the
jack until the tractor w heel is on the ground. Do not remove the
jacks and stands until the w heel nuts have been fully tightened.
Remove the jacks, vehicle stands and the blocks of timber and
return them to the appropriate storage place to prevent
deterioration.
SUMMARY
Tractors and other large farm equipment are a necessity for the
efficient day to day operation of farming. How ever, if not
maintained and operated correctly, they can be very dangerous.
In Western Australia, more people are injured or killed in accidents
involving tractors than from any other piece of farm equipment.
Most of these accidents can be prevented if the right equipment is
used for the right job, the correct procedure is used when doing
the job and the equipment receives regular maintenance.
PAGE 14 SAFETYLINE INSTITUTE JANUARY 2007READING – SAFE JACKING OF TRACTORS
Preventative maintenance of all farm equipment should be carried
out during quiet periods to avoid the need for major repairs during
busy periods.
Here are some important points to consider:
• Do not take short cuts.
• Only use the correct equipment for the job.
• Do not become so familiar w ith your equipment that you ignore
danger signs.
• Alw ays follow a set safe procedure.
Your feedback
WorkSafe is committed to continuous improvement. If you take
the time to complete the online Feedback For m at the SafetyLine
Institute w ebsite you w ill assist us to maintain and improve our
high standards.
REFERENCES AND FURTHER READING
WorkSafe WA. Safe Use of Farm Tractors. WorkSafe WA.
Australian Standard 2538-2004. Vehicle support stands.
Australian Standard 2550.1-2002/Amdt 1-2004. Cranes ⎯Safe use
- General requirements.
Australian/New Zealand Standard 2693:2003/Amdt 1:2004.
Vehicle jacks.
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