Repair work

Tanks, pressure vessels and pressure accumulators

Any work on vessels containing or having contained

 combustible or combustion-accelerating substances,

 potentially explosive substances or

 substances susceptible to develop harmful gases, fumes, mists or dusts during welding may only be carried out under expert supervision and only by experienced personnel especially assigned to such work.

This prescription applies, for instance, to all tanks and reservoirs for hydraulic fluid, engine oil, diesel fuel or lubricating grease.

Welding work on pressure vessels and pressure accumulators is forbidden.

Pressure vessels containing cold-starting fluid (ether) may be installed in or near the engine compartment.

Ether is toxic and highly flammable; the vessels are under pressure. These pressure vessels can explode if exposed to high temperatures (above 49°C / 120°F) or in the event of damage.

Protect the vessels against damage and high temperatures.

Do not perform welding work in the vicinity of these pressure vessels before they have been covered up safely against accidental contact or flying sparks. Have the pressure vessels removed from the machine, if safe protection cannot be ensured.

Inform yourself about the locations in the machine where the pressure accumulators of the hydraulic system are installed. Do not perform welding work in the vicinity of these pressure accumulators before they have been covered up safely against accidental contact or flying sparks. Have the pressure accumulators removed from the machine, if safe protection cannot be ensured.

Slewing rings and articulated joints

The welding current must not flow through ballbearing or roller-bearing slewings rings, through bolted connections or articulated joints or through hydraulic cylinders.

An electric current flowing through an air gap (e.g. in the bearing or in the articulation) produces a spark which damages the metallic surface.

The welding clamps must therefore always be connected very close to the weld area (max. 2 - 3 m away (6.6-9.8 ft)).

Information relating to the electrical system and to electronic modules

Electric arc welding produces electromagnetic fields, electrostatic charges and voltage spikes which can cause damage to electronic modules. Although the electronic modules of the machine are carefully protected against these influences, it is nevertheless necessary to take additional precautions in order to prevent such damage to the greatest possible extent.

• Switch off the electrical system ("ignition OFF").

• Open the battery main switch (or disconnect the starter batteries from the machine).

• Lay the welding cables as far away from electric lines as possible.

If it is not possible to implement all of the abovementioned precautions, all connectors must be removed from the electronic modules before beginning any welding work.

• Protect withdrawn terminals and connectors from short circuits and soiling. Cover up terminals and connectors with foils or adhesive tape.

• Never touch the enclosures of electrical and electronic modules with the welding electrode.

• Protect electric lines against the heat emanating from the weld area.

• Restore all electrical connections when the welding operations are terminated.

Never connect the ground clamp of the welding cable to the enclosures of electric or electronic modules.

Welding on the counterweight

Counterweights may contain a build-up of flammable gases. Before starting to work, counterweights must be flushed for at least 20 minutes with compressed air in order to remove these build-ups of gas. To permit flushing, the counterweight has two bores in its upper part: a threaded bore M18x1.5 for the compressed-air line and another unthreaded bore to let the air out.

Detailed information / instructions on this subject can be found in Service Information 2006-33 which is available on the Bucyrus HEX website under Maintenance & Service.

Welding on components of the working equipment and on other fully or partly closed steel structures

Components may be equipped with pipelines routed inside. These lines can contain combustible substances such as hydraulic oil or lubricating grease which may be set on fire by welding operations.

• Check whether pipes or hosepipes are connected to the steel component.

• Depressurize these lines.

• Open the screwed connections and empty the lines routed inside the component.

• Start welding only after these operations have been carried out.

Electric lines may also be be laid inside partly open steel structures in order to protect them against damage. They are not always visible from each viewing direction. Electric lines may catch fire as a result of the heat produced during welding.

• Therefore check carefully whether electric lines are laid in the vicinity of the weld area.

• Protect electric lines against the heat produced at the weld area or have them removed before starting the welding operations.

Welding on the cab

The driver's cab is designed in such a way that it meets the FOPS (Falling Objects Protective Structure) requirements in accordance with DIN EN ISO 3449.

Welding and other mechanical work is forbidden as there is a risk of reducing the structural stability of the cab.

Further information

More detailed information concerning the state-ofthe-art execution of welding operations can be found in the technical handbook "Welding for maintenance and repair".

For problems or queries please contact the competent service personnel.

If parts of the machine have to be removed or dismantled, please read and observe the chapters: "Assembly of working equipment, safety instructions",

"Inspection and servicing, safety instructions", "Repair, safety instructions".

Disposal At The End Of The Service Life

Dismantling and removal instructions

Before beginning work, think about the risks involved, e.g.:

 Most of the machine components have considerable mass. Therefore use only lifting gear and slings of sufficient bearing capacity.

 Risk of residual pressures still in the hydraulic system. Be very careful when opening hydraulic lines.

Read the following text attentively and observe the instructions given. Respecting the instructions will help you to protect yourself against health hazards and injuries and to prevent avoidable environment pollution.

Risk of deflagrations

In the course of time, flammable gases may have formed or accumulated in the hollow spaces of welded constructions, e.g. the counterweight. To remove these flammable gases, the hollow spaces must be purged carefully with compressed air before work with hand grinders, flame cutters or other sparking tools is being undertaken.

Risk of fire

Remainders of fuel or oils may lead to the formation of flammable gases in tanks or other hollow spaces. When these tanks or hollow bodies are cut into pieces, the gases may ignite or even explode. For this reason, remove all fuel or oil remainders from these components and purge them carefully with compressed air in order to eliminate flammable gases (other efficient methods of removing flammable gases can also be applied) before work with hand grinders, flame cutters or other sparking tools is being undertaken.

Disposing of the machine without polluting the environment

Before stripping down the machine at the end of its service life observe the following instructions: The assemblies of the machine contain various operating fluids or lubricants. These substances may pollute the environment (so-called hazardous substances) and must therefore be disposed of properly.

Observe the national laws and regulations governing the non-polluting disposal of these substances. Remove all operating fluids from the systems, remove all lubricants and dispose of these substances properly.

 Fuel system: fuel tanks, fuel filters, fuel lines, filling station. Auxiliary attachment and units, such as an onboard crane or an auxiliary heater have their own fuel tanks with the correpsonding line systems.

 Hydraulic oil: hydraulic oil reservoir, hydraulic cylinders, hydraulic motors, hosepipes, piping, hydraulic pumps, hydraulic valves, hydraulic oil filter, filling station.

 Engine coolant: engine, radiator, expansion reservoir, piping and hosepipes, filling station.

 Gearbox oil in swing, travelling and transfer gearbox systems, expansion tanks, piping and