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8/13/2019 GET Operator Technices Loader
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Ground Engaging ToolsGround Engaging ToolsLoader Operator Technique
PEXT9050
8/13/2019 GET Operator Technices Loader
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Ground Engaging ToolsGround Engaging Tools
Wear
Loader Operator Technique
Correct Position Incorrect PositionPEXT9050
Left: Correct position
Right: Incorrect position.
- Change of direction accelerates wear.
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Ground Engaging ToolsGround Engaging Tools
Wear
Material Flow Material Flow
Loader Operator Technique
PEXT9050
Left: Correct
Right: Incorrect - When the machine is operated incorrectly like this, what also happens?
- Because youre pushing a much bigger footprint through the material, it takes a lot more
fuel and increases wear and tear on the: -- Engine -- Machine -- Bucket
Also, it doesnt clean up the pit floor... leading to:
- Tire wear or splits.- Rolling stress on the machine and operator.
- Slower cycle time leading to reduced productivity.
What happens if the base edge is nose down?
- Wear is transferred to the top of the tip pocket, top of the base edge and internal bucket floors.
- If its a spade edge, the tires become highly exposed to damage from rocks.
What causes the misalignment of the bucket?
- The bucket leveler is not set correctly.
- The bucket leveler is not checked frequently, i.e. maintained..
- Operator override of the bucket leveler.
Over time weve found some operators dont understand the purpose of the bucket leveler. In these cases, the operator setsthe heel of the bucket on the ground to enter the pile. This is because he can see it and believes it to be in the correct
position.
The correct position is to set the base edge parallel to the floor with the tips nearly touching the floor. In this position, the
heel of the bucket will be off the ground.
Heres an example of where excessive pocket wear on tips can lead us to a poor operating technique which will result in
significant unnecessary cost to a customers operation.
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Ground Engaging ToolsGround Engaging Tools
Loader Operator TechniqueIf the machine is operated with the heel down
Penetration is reduced
Cycle times increase
More fuel is required
If the machine is operated with the nose down
Tire wear can be increased due to exposure to rocks left on the
pit floor
Changing the operational envelope
Changes the wear pattern
Load forces on the machine
Can cause additional unnecessary wear protection to be added
PEXT9050
( Run through the above )
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Ground Engaging ToolsGround Engaging Tools
Loader Operator Technique
Maintain bucket positioner in
proper alignment
Base edge parallel to floor
Cat buckets are designed for the
material to slide over a flat floor
Operation outside the design
envelope changes the wear
pattern of the bucket and GET
and affect loading Align positioner correctly
PEXT9050
Many time the bucket angle it set incorrectly .
Buckets are designed to have the base edge parallel to the floor. This allows
the material to slide over the edge and floor with the least amount of
resistance to load the bucket. This also minimizes wear.
Any changes to this will result in wear occurring somewhere else . where
it is not protected. More fuel will be required, there will be more stress on the
machine, loading will not be as efficient, and the tires could be unnecessarily
exposed to wear.
Therefore, it is important to have this set up correctly at all times.
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Ground Engaging ToolsGround Engaging Tools
Loader Operator Technique
VIMS Keypad
View bucket kick out via VIMS
Keypad
585 Tilt Linkage parameter
Should read 65%
PEXT9050
Use the VIMS key pad to view the bucket angle. If the bucket has been set up
correctly for operation with the base edge parallel to the ground the individual
will read 65.
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Ground Engaging ToolsGround Engaging Tools
Loader Operator Technique
PEXT9050
Here we have a couple of good examples of worn out tips; clear evidence of the
machine being operated with the heel down. Worn GET is a library of stored
information that is often the only real evidence you have on how the machine was
operated. Worn GET should be used as an integral part of operator training and
management to help keep the machine at its optimum performance level.
What SOS is to power train, worn GET analysis (boneyard) is to implement
operator technique. Steel has memory and in this situation the wear pattern shows
you how it moved through the ground. From this you can determine the position of
the implement and how the machine was run. A valuable tool to help people
improve their performance through a simple application of cause and effect
information is stored in the worn out GET
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Ground Engaging ToolsGround Engaging Tools
Loader Operator Technique
PEXT9050
Overnight the machine was left standing and the base edge rusted in the moist
nighttime air. Why did it only rust along the edge?
Because this was the only area that was wearing . Because only this part of
the edge had been in contact with the ground.
Why? Because it was operated with the nose down.There will also be other evidence supporting this, but the rust is a quick indication
of what to look for.
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Ground Engaging ToolsGround Engaging Tools
Loader Operator Technique
PEXT9050
The wear on the front of the end bit, and the front of bolt heads, compared with very
little wear at the back is clear evidence of the bucket being angled too far forward.
In the correct position, with the base edge level to the ground, the wear would be
even with most wear at the leading edge.
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Ground Engaging ToolsGround Engaging Tools
Wear profile shows the angle of operation
Nose angled downwards before edge was rotated
Cutting edge is being operated outside the design envelope
Will reduce cutting edge, base edge and inside bucket floor life
Loader Operator Technique
PEXT9050
In this photo all the wear is on the back of the edge. The cutting edge has been
rotated.
Comparing the angle of wear to that of the base edge you can see how far forward
the bucket was positioned taking it right out of its design envelope.
The wear rate on the edge is increased when operated in this position as well.Instead of presenting the larger flat surface on the bottom of the cutting edge to the
ground, only the front portion is in contact. This will concentrate heat and material
flow to the top and bottom of the bevel causing it to wear much faster than it would
if operated correctly
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Ground Engaging ToolsGround Engaging Tools
Loader Operator Technique
PEXT9050
Here is an example of nose down wear. This time it is on a segment bucket
using abrasion tips and half arrow segments.
The scalloping is normal in many operations. Its important to keep an eye
on the replaceable iron wear. When replaceable iron becomes minimal iron it
should be replaced or relocated.
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Ground Engaging ToolsGround Engaging Tools
LHSLHS
RHSRHS
Loader Operator Technique
Enter the pile with the
bucket square to the face
More contact on
one side
Equals more
wear
Stresses bucket,
linkage and
hinge pin
Adapters wear on
one side and weld is
washed out
PEXT9050
ALL LOADERS ARE DESIGNED TO ENTER THE PILE SQUARE TO
THE FACE. Turning into the pile or loading on one side, places great stresses
on the machine and is twisting the bucket and articulation joint. Additionally,
loading efficiency is decreased. There is nothing to gain by side loading .
However, it will substantially increase the cost per ton.
GET wear analysis (boneyard) is a great management tool to help prevent this
from occurring.
The GET will wear more on the side of initial contact. In the top photo we can
see the wear on the LHS of the tip, adapter and adapter weld. Instead of the
material flowing over the top from the front, the material is coming in from the
side. The change in flow direction to get around these components results in the
side wear. On the RHS which is now the trailing edge you can see the wear rate
is very low by comparison. This side is being shadowed by the LHS.
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Ground Engaging ToolsGround Engaging Tools
Never operate a bare
bucket
Minimize ground contact.
Make the tips do the work
Loader Operator Technique
PEXT9050
Never operate a bare bucket. It is a structural component of the bucket, protect it.
A worn base edge will cause the bucket to crack and fail resulting in expensive
downtime and repairs, and will reduce the buckets load capacity and be more difficult
to load.
Minimize ground contact. Contact = Wear = CostIf the contact is not productive, dont do it.
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Ground Engaging ToolsGround Engaging Tools
Minimize ground contact.Make the tips do the work
Loader Operator Technique
PEXT9050
Heel plates are to protect the bucket hinges from wear that occurs when the bucket is
not loaded correctly.
Correct loading requires the lift arms to be raised, then the bucket to be curled. This
raises the bucket out of the wear material to reduce contact and wear while curling. If
curling commences while the bucket is still in the pile the result will be unnecessary
wear. Make the quick-to-change components wear, not the more difficult to replace
and more costly components.
A clean floor is very important for tire life .. Unnecessary cleaning is just as
costly as no cleaning. There is a balance