Low Boy, Big Comeback
A shop running a Pines #4 Low Boy on their production floor reached out after their cylinders started showing signs of fatigue and the swing arm bearings were past due for replacement. Rather than risk unplanned downtime, they had us tear it down for a complete rebuild — with a new digital control to modernize the operator experience along the way.
This rebuild replaced the swing arm bearings, keys, and fasteners; re-machined both slides with new phenolic wear strips; rebuilt every major hydraulic cylinder (bend, mandrel, booster, clamp, and pressure die) through a certified cylinder repair facility; and added a new Sierra Corp. digital controller backed by a 2-year warranty. The machine was cleaned, sanded, repainted in the customer’s chosen color, cycled, and tested before delivery.
Hydraulic Cylinder Rebuild Process
Every major hydraulic cylinder — bend, mandrel, booster, clamp & pressure die — is sent to a certified cylinder repair facility and warrantied. That facility does not use V-packing (they won’t warranty a cylinder built with it), so the V-packing pocket is replaced with a gland insert using a poly-pak & seals instead. Rods, barrels, or heads are replaced as needed as part of the rebuild; any cylinder damaged beyond repair is replaced outright with new.
New mandrel extractor cylinder & new PDA cylinder
New mandrel turnbuckle
New die stud & nut, new back-up blocks
Remaining Hydraulic Updates
Hydraulic tank cleaned
New hydraulic hoses & fittings, new hydraulic valves & manifold
New oil sight gauge
New Lube USA electronic slide lubricator — junctions, meters, line, ferrules, hose & fittings
“The greatest improvement on this machine is the linear rail and pressure die holder with the outboard support because I can move it in and out with one hand.”
Richie, Kottler Metal Products, Ohio
Swing Arm and Stationary Arm Refurbished
Swing Arm (LH, counter-clockwise rotation):
- Removed & inspected
Repair bend die keyway, pin holes, or stripped die mounting bolt holes (if necessary)
Re-cut spindle keyway (if necessary)
Remove & replace Timken cup & cone bearings
Replace spanner nuts — (1) standard & (2) Taperline locking style
New spindle key, new bend die key
Replace fasteners; repair broken bolt for slide hold-down (if necessary)
Stationary Arm:
- Removed & inspected
Repair pin holes (if necessary)
Replace fasteners
Both arm slides re-machined with new phenolic wear strips. Wear strips, slide wiper ways, gibs, bushings in toggle links, pins, snap rings & grease zirks all replaced with new.
New Sierra Corp. Digital Controller
New Sierra Corp. digital controller (2-year warranty on the control)
Additional Updates
New rear sprocket pin & bushings
New front & rear bend chain and connecting links
Welded arm stop on stationary arm removed, replaced, and reset so arms run parallel
Pressure Die Assist Holder Assembly: R&R bearings, new support blocks, new pins, machine key (if necessary)
New master bar assembly
New front drive sprocket for swing arm
New wear plates for booster guide & wiper ways
Machine cycled & tested — sample material and a set of tooling required from customer for run-off
Machine cleaned, sanded & painted — customer color choice
