Roll-out Cantilever Rack for Pipes and Bars – 6-Meter Lengths

Why 6 metres is the awkward length

Mill lengths of pipe, tube and square bar cluster around 6 metres because that is what fits a standard 40-foot container and what most cutting tables accept. It is also the length where floor stacking starts to fail visibly: a bundle stacked three high needs a bay roughly 7 metres long and 1.5 metres wide, and the bundle at the bottom is unreachable until everything above it moves.

Saw and laser operators feel it first: the nest is ready, the machine is warm, and the material is under four other bundles.

Support points, sag and the case for three arms

A horizontal pipe is a beam, and deflection grows sharply with span — doubling the distance between supports multiplies sag several times over. Support a 6-metre length only at its ends and the middle drops, the bundle settles into a shallow curve, and the first cut can come off square by more than the tolerance allows. Three arms per tier, set at roughly equal spacing, cut the unsupported span to about 3 metres and keep the stock straight enough for precision work.

Herochu sets arm count per tier from the stock you list, not from a standard drawing. Thin-wall tube in long bundles and solid square bar behave differently under the same span, and the arm section follows that difference.

Rack length, overhang and end stops

The rack should be a little longer than the longest stock it holds — typically 6.3 to 6.5 metres of frame for 6-metre material. That allowance gives the crane room to land a bundle without threading it between columns, and it stops the pipe ends from cantilevering past the outermost arm.

End stops are not optional at this length. A 6-metre bundle that shifts 300 mm during a lift puts its centre of gravity outside the arm base, and the load goes over.

Tier pitch against your crane hook

Each tier needs clear vertical space equal to the bundle height plus the sling and spreader you actually use — commonly 800 to 1,000 mm. Six tiers at that pitch land near 5 metres of frame height, which is why the crane hook height, not the available wall space, usually sets the tier count.

A rack that is one tier too tall is worse than a rack with one tier fewer. Operators start dragging the top bundle out sideways because the hook will not clear it, and the scratch damage that follows is written off as normal wear.

How a 6-metre tier extends without twisting

A long tier is a torsion problem. Pull one end of a loaded 6-metre arm assembly and the free end lags, the tier racks sideways in its guides, and the rollers take a load they were never sized for. Long-stock roll-out tiers solve this with a carriage travelling on both columns, a synchronised drive, and guide rollers that keep the tier square through the full stroke.

On the Herochu crank-out version, the tier runs out on a geared crank with a positive stop at the extended position, and the arms are braced so a full bundle does not droop toward the level below. Electric telescopic versions do the same with a motor per tier and limit switches at both ends.

Loading a 6-metre bundle with a spreader

The lift itself is where most damage happens. Two slings choked at the quarter points will bow a bundle; a spreader beam at the same points keeps it flat. The sequence that works: extend the tier, land the spreader over the bundle centre, take up slack, lift vertically, traverse to the machine, lower onto the feed rails, retract the empty tier.

Keeping the rack parallel to the cutting cell — not across the aisle — shortens that traverse to a few metres. Material flow stops competing with forklift traffic, and the cell keeps running.

Transport, floor and installation

Six-metre frames ship as bolted column sections rather than one welded piece, which keeps freight inside container limits and lets a two-person crew assemble on site. What matters at installation is level across the full length: a 6.5-metre run that is 5 mm out of level loads unevenly, and the crane operator feels it on every lift. Herochu supplies base plate and anchor layouts per project and checks floor flatness before the frame goes down, because correcting it afterwards means unloading the rack.

FAQ

How many arms does a 6-metre pipe need? Three per tier is the practical standard for precision stock. Two arms work for short, stiff sections and light bundles where some sag is acceptable.

Can a 6-metre rack fit a standard shipping container? Yes, when columns are supplied in bolted sections. Fully welded 6.5-metre frames need flat-rack or break-bulk freight, which adds cost and lead time.

What aisle width does the crane need? Enough for the hook block to pass and the bundle to swing clear — usually 1.5 to 2.5 metres in front of the extended tier, measured against your actual hook block.

Will one tier hold a full mill bundle? That depends on the bundle weight and the arm load centre. Send both to Herochu with the stock list and the tier rating is calculated rather than assumed.

Key takeaways

Six-metre stock rewards three-point support, a frame slightly longer than the material and a tier that stays square through its full travel. Match tier pitch to hook height, keep the rack beside the machine, and the pick becomes a vertical lift instead of a handling job.