Need a line boring company that restores worn bores to OEM spec?

Worn pin bores, sloppy pivots and misaligned housings do not just slow a machine down - they create repeat failures that cost far more than the first repair. Renjohn lines up, machines and rebuilds critical bores for earthmoving and industrial components so the repaired part fits correctly, runs true and lasts longer in service.

A line boring company is only as good as the accuracy of its setup, and Renjohn treats every bore as a precision repair rather than a quick fix. We restore worn or damaged bores on earthmoving, aircraft and commercial components, then machine them back to the required dimensions so pins, shafts and bushes seat properly. Because we also offer TIG welding, thermal spraying, grinding and machining in-house, we can rebuild the surrounding material before the final bore is cut. The result is a stronger repair path for clients who need components returned to OEM or required specifications with reliable fit and alignment.

What you get

• Precision Bore Recovery — We rebuild worn housings and pivot points to the correct diameter and alignment so the repaired component works as intended.
• Complete Workshop Capability — Our line boring work can be paired with welding, spraying and machining to repair the full component instead of only the damaged hole.
• Built for Heavy-Duty Equipment — We focus on earthmoving repairs where loader arms, buckets, frames and brackets need accurate bore restoration under demanding conditions.
• Quality-Controlled Output — Renjohn works in accordance with ISO 9001:2015 and SANAS standards, giving you a repair process built around consistent workmanship and traceable quality.

How it works

1. We assess the worn component, measure the damage and confirm the bore size, alignment and surrounding material condition before any cutting begins.
2. If the housing needs rebuild work, we restore the area with welding or thermal spraying so the final bore has a sound base material to work from.
3. We set up the component on our line boring equipment, machine the bore to specification and verify fit against the required pin or sleeve dimensions.
4.

Frequently asked questions

Q: What does a line boring company repair?
A: A line boring company restores worn or misaligned bores in heavy equipment and industrial components so pins, shafts and bushes fit correctly again. At Renjohn, that includes parts that have ovalled out from wear, impact or repeated movement under load.
Q: When is line boring better than replacing the part?
A: Line boring is often the better option when the base component is still structurally sound but the bore has worn beyond tolerance. It can save time and cost while preserving the original part geometry and mounting points.
Q: Can you combine line boring with welding or spraying?
A: Yes, and that is often the best repair path for badly worn components because the damaged area can be rebuilt before the final bore is machined.

Line Boring Company | Renjohn Earthmoving Repair Specialists Worn pin bores, sloppy pivots and misaligned housings do not just slow a machine down - they create repeat failures that cost far more than the first repair. Renjohn lines up, machines and rebuilds critical bores for earthmoving and industrial components so the repaired part fits correctly, runs true and lasts longer in service. Our workshop combines line boring with machining, welding and thermal spraying to recove