Line boring is a machining process we use to repair worn out bores that pins fit into and bushes press fit into on all kinds of earth moving machines and there attachments. Some of the issues found when we attend jobs are that the holes are worn due to a lack of maintenance, bores misaligned from previous repairs or sometimes from factory.
Some of our past line boring repairs have been on excavators and there components such as booms and sticks, quick hitches and links, buckets and grapples. We have carried out repairs on wheel loader center hitches, load frames, zed bars, dog bones and buckets. Other machines have been dozers, graders, moxi trucks, compactors, rollers and cranes.
There have been many incidents of pins snapping during machine use which have caused ears to bend and break, this has also happened from cracks that have formed around bosses or ears on load frames, dog bones bending, zed bars cracking or bending etc,
We also repair damaged ears weather they have snapped off or bent out by cutting new profile sections on our CNC water jet cutter using 350 grade mild steel. The new sections are then welded in place and the line boring process can begin.
Here’s a brief overview of the process we follow:
- Inspection: We will inspect the required line boring components and will come up with a conclusion for repair.
- Line Boring Process:
- The line boring machine is set up and aligned.
- The boring bar takes a clean cut of the hole to remove any damage that is there or to make a oval hole round again.
- Then we install our bore welder and start the welding process of building up the hole to make it under size, depending on previous damage this can take one or several passes.
- Next stage is to re install the boring equipment and begin the machining, using a carbide tipped insert the holes are machined to suit a pin or under sized to install a press fit bush..
- Measurements and precision tools are often used to ensure that the newly bored hole meets the required specifications.
- Applications: Line boring is commonly used in various industries, heavy equipment maintenance, and other applications where precision alignment of components is essential.
Overall, line boring is a machining technique that helps maintain or restore the accuracy and functionality of machinery by ensuring that holes and bores meet specified tolerances.
Line boring is a service we offer for earth moving plant equipment and machinery. It is a service that comprises of repairing worn and damaged boreholes. This damage can be caused by misalignment of bores, a lack of grease from maintenance or blocked and damaged grease nipples, worn or out-of-round damaged bores due to fatigue and excessive use.
The line boring equipment is powered by a hydraulic drive system that turns a 2-inch solid bar with a carbide tip cutter, this in effect is like a lathe fitted to the machine or attachment and the machining and repair can begin. We can repair holes from 40mm to 350mm in size onsite or at our workshop in Ravenhall Vic.
The machines we repair can be found on construction sites, quarries, mining, civil projects, waste and recycle industries, cranes and forklifts, hook lift bin trucks, cranes etc.
Some of the items we can repair are excavator sticks and booms, quick hitches, excavator buckets, centre pins on grapples and grabs, hydraulic cylinder eyes, centre hitches on wheel loaders, Load frames, dump truck body’s, graders, waste material handlers, dozer blades and worn holes on push arms, worn holes on equalizer bars, and all.
Mud Bucket Line Boring
Line boring worn bosses on this mud bucket, all bores machined to clean up the holes then welded and machined to suit new pins.
Komatsu zed bar repair
These ears are 50mm thick plate and have bent out due to the pin snapping, we have carried out this repair using our 150 ton workshop press followed by line boring both jernals to suit the new pin.
