Symmetrical Group

Policies and Procedures

OHS&E\SAFETY PROCEDURES

SG-PR-33-16 Mobile Crane Safety

1. introduction

Operators of mobile cranes on Symmetrical Group sites shall be licensed, authorised and competent to operate the type of crane to be used.

There are particular hazards when operating mobile cranes.  Operators, dogpersons and personnel in the vicinity of operating cranes must be alert to the potential for injury and\or damage at all time.  These hazards include:

• collision of the crane jib or its load, with personnel, equipment or buildings,
• contact with live overhead eletricity cables,
• overturning of the crane during lift,
• introduction of a source of ignition to a hazardous area,
• damage to underground services, such as pipeline and drains.

This guide manual describes the safety controls and precautions to be followed when using mobile cranes.  Conditions and requirements for the operation and use of cranes shall be in accordance with:

• Occupational, Safety and Health Regulation 1996,
• AS 2550 Cranes, Safe Use, in particular AS 2550.1 General Requirements, AS 2550.5 Mobile and Vehicle Loading Cranes,
• AS 1418 Cranes including hoists and winches, in particular AS 1418.1 General Requirements, AS 1418.5 Mobile, Vehicle Loading and Vehicle Tow Cranes.

2. Pre-use checks

2.1. pre-start checks

Regardless of the age of a mobile crane, it is important that routine checks are done at the start of each shift.  These checks are essential for the safe and efficient operation of the crane.

The checks will provide the opportunity to inspect for any damage that may have occurred while the crane is parked.  The checks will also go a long way towards keeping the crane down-time to a minimum.

The essential points that should appear on a pre-start check list are:

• Check that the engine crankcase oil level is correct.
• Check that the transmission case oil level is correct.
• Check that the radiator coolant level is correct.
• Check that the tyre pressures are correct.
• Check that the hydraulic hoses are not damaged or leaking.
• Check that running ropes are not damaged and they are spooled correctly  on the winch drum.
• Check that there is adequate fuel for the work to be done.
• Check and clean the windows.
• Check that the operator’s cabin is free from loose objects and other matter that could interfere with the operation of clutches, brakes and levers.
• Check  that the outrigger supports are not damaged, especially when the crane has been parked in its operating position.
• When necessary, carry out daily lubrication in accordance with the operators manual.
• Before starting, check that the brakes and all control levers are in their neutral position.

After starting the crane, it is important to check all onboard function displays and controls for correct operation.

do not use the crane if defects or a faulty control function have been detected.
defects are to be reported to the responsible officer immediately.

2.2. Flexible steel wire rope (fswr)  defects check

Moving and standing parts of the wire ropes shall be closely examined for wear, broken wires, corrosion, kinks and crushing.

Some defects or deterioration can be tolerated, but if wire rope wear or damage exceeds the following limits, the rope shall be replaced:

• Wear: The wire rope shall be replaced when the wear on the outer wires of the rope exceeds 33% of its original diameter.
• Corrosion: Corrosion may occur on the surface of both the inner and the outer wires.  It is more dangerous than wear because, usually , more wires are affected by a loss of material.  Wire ropes shall be replaced when the corrosion has caused a loss of wire material.
• Kinks: Kinks are usually caused by poor handling.  Running wire ropes shall be replaced where a wire rope is deformed by a kink.
• Broken Wires: Wire Ropes shall be replaced when the total number of broken wires measured over by a rope lay length exceeds 10% of the total number of wires in the rope length (A rope lay length is the distance for the lay of one strand as it travels 360o around the rope.)

For example, a wire rope of 6 x 24 construction would contain a total of 144 wires.  Ten percent of this total number would be 14.  So, if the total numbers of broken wires measured over a rope lay length in the worst section of rope is less than 14, the rope is still serviceable.

For further information on Australian practice concerning wire ropes, refer to AS 2759 Steel Wire Rope - Application Guide.

2.3. Loading

Operators and dogpersons must understand and check the weight or load charts applicable to the crane to be used.

ascertain the weight of all loads before lifting.

Weights shall be marked on loads, contained on manifests or shown on drawings.  If the load weight is not available, estimate the weight (using weight charts or tables) and include the weight of lifting beams, chains, slings, block and hook.  (Hook could weigh up to 1 tonne on a 50 tonne crane).

• All cranes 16 tonne and upwards have a load indicator in the cab.

do not raise a load if it exceeds the safe working load (SWL) indicated on the load chart of jib extension.

2.4. setting up and crane stability

The crane shall be set up correctly, before a load is lifted, to ensure stability whilst in operation.  The following points shall be taken into account:

• set up on level ground, not slopes,
• ensure the load is not tied down, bolted or liable to be caught in or under something,
• use solid blocks under the outriggers to spread the load over a greater area, and
• ensure the terrain has suitable capacity to bear the load.

3. crane signals

If, at any stage of the operation, the crane operator does not have a clear and unobstructed view of the load and its vicinity, or the point of attachment for a load, a competent person, trained in slinging or rigging, must be appointed as the dogperson.  Only the appointed dogperson shall give the necessary signals to the crane operator, using the signals as shown in  Signals for Crane Operators (Form No. IF1373).

• Two way radio shall be used when the crane operator and dogperson cannot see each other, and the bell, whistle or buzzer signal is inappropriate

4. precautions

4.1. general precautions

Observe the following precautions when operating a mobile crane:

• Do not leave a crane unattended, even for a short time, unless all loads have been removed,  the engine shut down and brakes applied.
• Do not operate a crane in high wind, or where there are strong gusts of wind and do not lift a large load in windy, or gusty conditions.
• Do not use flat web slings to raise, lower or suspend a load.
• Do not use a fibre rope sling if a suitable steel wire rope can be used.
• Faulty slings shall be tagged with an Out of Service Tag and returned to the Team Leader -Equipment Support for repair or replacement.
• Discard any wire rope used on a crane, when the visible number of broken wires in any length of rope diameter exceeds 5% of the total number of wires in the wire rope (refer also to 1.2).
• Check that there are no loose objects on a load that could fall during lifting.  Pay special attention to the tops of the containers.
• All lattice boom cranes fitted with outriggers will have the outriggers installed and operational at all times.  No slewing of these cranes is to take place unless outriggers are fully extended and in place.
• Do not use the crane to drag the load along the ground.  Severe overloading may result.
• Do not exert a sideways pull on a shackle or eyebolt.
• Lower the load under crane power, except where a chain and block system is attached between the crane hook and the load.
• The work area, equivalent to that of the extended jib, should be barricaded off to ensure unauthorised personnel do not enter the area.

if a tipping sensation is felt, lower the load, not the boom.  lowering the boom will make it worse.

not all wheeled cranes are suitable for travelling with loads attached.  See load chart for details.

• A crane chaser or dogperson shall walk alongside a load using tag lines attached to the load, slung from a crane while the load is being transported form one area to another.
• A Load may be tied back to the crane to prevent the load from swaying, whilst the load is being transported.

do not operate a crane closer than 6 m to any overhead powerline or electrical conductor, without appropriate safeguards to prevent accidental contact.

• Use tag lines to prevent loads from turning or swaying while the crane is in motion of lifting a load.
• Avoid sudden braking and fast hoisting, luffing and slewing.
• Do not under any circumstances, use a crane to lift a load over personnel, or allow anyone to ride the load.
• Keep personnel well clear of the suspended loads.
• BHB tractor cranes shall be fitted with a safety fender (see Figure 1).

4.2. plant area precautions

• Unless there is no alternative, do not operate a large crane over live process equipment.  If such an operation is unavoidable, a Special Work Permit must be obtained.
• Within 50 m of the ammonia storage tanks and the ammonia nitrate tank, maximum outrigger loads are not to exceed 20 tonne/metre2 (t/m2).
• Crane drivers are to be instructed not to exceed a ground loading of 20 t/m2 on any outrigger at any time.
• The area of support blocks under outriggers is to be estimated as follows:

Area of block (m2) = Gross Weight of Crane  +  Weight to be lifted

20

4.3. Accidental contact with electrical cables

If a crane contacts electrical cables, the crane operator shall:

• Remain in the cab.
• Keep still.
• Avoid touching any part of the crane.

Other personnel shall:

• Summon an electrician.
• Keep well clear, and do not touch any part of the crane until the power is switched off.

5. Crane personnel work box

A crane personnel work box shall only be used where there is no practicable safe method of access.  The Special Permit for using the personnel work box to lift personnel shall be obtained and completed, and the conditions

Date published: 25/07/2013

* -25/07/2013 12:27:06 PM