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Auxiliary Equipment

Decoilers, levellers and supporting equipment for complete roll forming lines.

Auxiliary equipment is everything in a forming line that is not the forming machine itself: the decoiler at the front, the leveling unit that conditions the strip, the slitting line that prepares coil to width, and the truss purlin line — which sits in this group because of who buys it rather than what it does.

It is worth reading this group before choosing a forming machine, because the front end decides the quality of everything downstream. A coil that goes into the rolls still carrying coil set or cross-bow comes out as a bowed profile no matter how good the forming section is, and that is far cheaper to solve at the decoiler than to correct later.

4 Models Available

Coil Handling and Line Support Equipment

All models available with matched decoiler, leveling unit and runout table as a complete line.

Selection guide

How to choose auxiliary equipment

What coil weight do I actually buy?
Standard coil is supplied at 3–5 tonnes, which is why most roofing and framing lines run a 3 T or 5 T decoiler. Guardrail and heavy purlin lines deal in 5–10 T, because the material is thicker and the coil is heavier. Size to the coil you can source, not to a round number.
Do I change coil often enough to need two heads?
A double-head decoiler carries two coil positions, so you load the next coil while the first is still running and change over without stopping the line. That saves roughly 10–20 minutes per coil change — clearly worth it on a line running continuously, much less so on one that changes coil once a shift.
Does my coil arrive with edge damage?
Coil that has travelled by sea commonly has crushed edges on the outer wraps. A decoiler will still uncoil it, but the damage carries into the finished profile unless there is a leveling unit in the line. If you buy export coil, plan the leveler as part of the specification rather than an option.
Is my problem coil set, or coil that is the wrong width?
Two different problems with two different answers. Coil set and cross-bow are removed by a leveling unit — seven rollers is the usual minimum for thin sheet. Cutting master coil down to the widths your lines need is a slitting line, which only pays above roughly 300–500 tonnes a year or where a service centre cannot supply the widths reliably.
How many different widths do I run?
Every width you buy in from a service centre carries a slitting margin, and if you run several widths you pay that margin repeatedly. A slitting line turns one master coil inventory into all of them, which also cuts your own stock holding. On a standard arbor line it cuts down to about 20 mm.
Do I already run a purlin line?
The truss purlin machine is a second-stage purchase for producers who already make C and Z purlins and want to quote longer roof spans. Per metre it costs more than a plain purlin because of the assembly step, but per unit of span it can beat a heavier single section. It is rarely the right first machine.
Profiles

Auxiliary equipment compared

EquipmentWhat it doesTypical rangeWhen to add it
Hydraulic decoilerHolds the coil and pays it off under controlled back-tension3 / 5 / 10 T · coil width up to 1300 mmOn every line — sized to the coil weight you actually buy
Decoiling & leveling machineRemoves coil set and cross-bow from the strip before forming0.3 – 4.0 mm · 7 / 9 / 11 rollersWhen coil retains its set, or after sea freight with edge damage
Steel coil slitting lineCuts master coil down to the widths the lines needSlit width down to 20 mm · coil up to 10 TAbove roughly 300 – 500 t per year, or where widths are hard to source
Truss & roof purlin machineForms triangulated chords for long-span roof members1.5 – 3.5 mm · section depth 100 – 400 mmAfter a CZ purlin line, when you want to quote longer spans
Before you order

What to fix before you order

01

Size the decoiler to your coil supply, not to the machine it feeds

A decoiler that is too small for the coil you can buy locally will stop the whole line, whatever the forming machine is capable of. Standard coil is 3–5 tonnes, so 3 T and 5 T cover most roofing and framing lines; step up to 10 T only when your material and your coil supplier justify it.

02

A coil car stops being optional above 5 tonnes

Loading a heavy coil onto the mandrel with a forklift alone puts the load on the mandrel and the coil edge, and both are easily damaged. At 3 T a coil car is genuinely optional; above 5 T it is standard practice.

03

Brake tension is the specification nobody asks about

Without controlled back-tension the coil over-runs, the strip goes slack, and the loop jumps or kinks — which shows up as inconsistent profile lengths rather than as an obvious fault. A band brake with tension control holds constant back-tension as the coil diameter falls.

04

Leveling is cheaper than correcting a bowed profile

If you run export coil or high-tensile steel, the leveling unit belongs in the specification from the start. Seven rollers covers thin sheet; nine or eleven are used above about 2 mm, and for higher-tensile material where more reverse bending cycles are needed to remove the set.

05

A slitting line is a volume decision, not a quality one

The case for slitting is economic: it removes the service centre margin on every tonne and lets one master coil become every width you run. Below roughly 300–500 tonnes a year, or with only one or two widths, capital cost and knife maintenance usually outweigh the saving.

06

Specify auxiliary equipment as a line, not as separate parts

The decoiler, leveler and forming machine run as one control system — tension, speed and loop have to stay synchronised. Whether the units are separate or combined, buy them together so the signals and speeds match, rather than adding a unit to an existing line afterwards.

FAQ

Choosing and buying Auxiliary Equipment — common questions

What decoiler capacity do I need?
Most roofing and framing lines use a 3 T or 5 T decoiler, because standard coil is supplied in 3–5 tonne weights. Guardrail and heavy purlin lines normally need 5–10 T, where the material is thicker and coil weights are higher. The right answer is the coil you can actually buy locally.
Do I need a leveling unit, or is a decoiler enough?
A decoiler only pays the coil off. Coil arrives wound under tension and keeps both coil set and cross-bow, and if those are not removed before forming, the finished profile comes out bowed or twisted. If you run export coil or high-tensile steel, plan the leveler in from the start — it is not a straightforward field addition.
When does a slitting line pay for itself?
Usually above roughly 300–500 tonnes a year, or where you need several widths a service centre cannot supply reliably. The gain is the slitting margin you stop paying on every tonne, plus the inventory saving from holding one master coil instead of several finished widths. Below that volume, knife maintenance and capital cost normally outweigh the saving.
Why would I want a double-head decoiler?
To avoid stopping the line to change coil. A double-head unit carries two coil positions, so you load the next coil while the first is still running, then change over without interrupting production. That is worth roughly 10–20 minutes per change, which adds up quickly on a line running continuously.
Can auxiliary units be added to a line I already own?
Yes. We can supply a stand-alone unit with its own control panel, or match signals to an existing line PLC — tell us the line make and control voltage and it will be configured accordingly. It is still easier and cheaper to specify the front end with the forming machine, because the speeds and tension have to be matched.
Is the truss purlin machine an auxiliary unit or a machine in its own right?
It is a roll forming line in its own right, listed here because of who buys it. Truss purlins are a specialist long-span product with a structural design process attached, so most producers add this line once they already run a CZ purlin machine and want to quote spans a single section cannot reach. It is not a first machine.

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