Roll Forming Machine
Roll forming is the process of bending strip into a finished profile at room temperature, one pass at a time, without melting anything.
In This Line
We build cold roll forming lines for open profiles: C, Z and Ω purlins for steel structures, made from strip without welding. For closed square and rectangular tube, see our direct forming square tube mill.
What Is Roll Forming?
Cold roll forming bends strip progressively through a series of passes at room temperature. There is no phase change and no melting — it is pure plastic deformation, which is why the two things that decide the result are the number of passes and the roll profile, together with the yield strength of the strip going in.
Cold Roll Forming Machine for C, Z and Omega PurlinsThere is no welding and no phase change — purely plastic deformation.See the line →
Metal Roll FormingRoll forming is a cold process.See the line →
Roll Forming Tooling & Die DesignOn the purlin line the roll body is bearing steel, hardened after machining, and the punch and cutter tooling is Cr12, also hardened.See the line →
Roll Forming Line for SaleWhat to check before the money moves: forming route, tooling material, and the supply scope actually quoted.See the line →That is the difference from a tube mill: a roll-forming line only shapes, while a tube mill shapes and then welds. The purlin line works by cold forming with no welding: the profile is formed by roll bending plus hydraulic punching and cutting, which is the structural difference from the welded pipe lines we build.
Roll Forming Machines & Cold Roll Forming Lines — Range, Configuration and Output
The forming section is an 18-pass roll former with hydraulic punching and cutting.
Purlin forming. A semi-automatic C/Z interchangeable line that produces multiple purlin sizes from one set of tooling through stepless adjustment — changing size does not mean changing rolls. It punches, cuts and forms automatically, reaches a forming speed of 20 m/min, and works material 2–4 mm thick.
Direct forming square. Closed square and rectangular tube is made on a separate line, covering 30 × 30 to 500 × 500 mm with wall 1.5 to 20 mm across seven bands.
Key Parameters: Size Range, Wall Thickness and Line Speed
The purlin line forms 2–4 mm strip through 18 passes at up to 20 m/min. Forming rolls are bearing steel, hardened after machining; dies and cutters are hardened Cr12. The full specification of the line is on the cold roll forming machine page. Material thickness, line speed and output are confirmed against your profile section, steel grade and finished length at quotation. Send us those three and we will state the figures.
Under-specified rolls or dies show up as poor profile edge lines, hole position drift and early blunting of the cutting edge.
How to Choose the Right Model
If the product is an open profile — C, Z or Ω purlin, or a similar cold-formed section — the purlin line is the one, and the decisive question is whether the size spread you run is inside what stepless adjustment covers, because that is what removes the roll change.
If the product is closed square or rectangular tube, the direct forming square tube mill is the relevant line.
The choice is decided by what leaves the line, not by throughput.
Scope of Supply, Installation and Commissioning
Purlin tooling arrives with one set of dies and cutters; Cr12 dies and cutters can be supplied continuously as they are reground or replaced by punching count. The line is dismantled into units and shipped in containers: heavy frames are braced and secured, while precision parts and wear items travel in wooden cases together with a spare-parts pack.
Rolls and key wear parts are machined in-house on our own CNC equipment, which is the reason spare tooling stays available years after handover. The engineering team is twenty people averaging twenty years’ experience, and the production base is open to factory audit.
Sheet metal roll forming machines for sale
Buyers comparing purlin lines usually check three things: whether a size change needs a roll change, how accurately holes are positioned, and the forming speed. On this line, size change is stepless with no roll change, the punching hole spacing adjusts from 45 to 650 mm, and forming runs at up to 20 m/min.
Certification
The company is certified to ISO 9001:2015, and our cold roll forming equipment is CE marked under the EC Machinery Directive 2006/42/EC. Tengtian holds a national high-tech enterprise certificate and a Madrid international trademark registration, and has 30 granted utility model patents, with 7 invention patents applied for.
Delivery, payment and after-sales
Standard lines ship within 90 working days of the deposit, with plant-level customisation scheduled from our own manufacturing base.
Installation and commissioning are guided on site by our engineers, with online support; the buyer provides the installation crew and covers the engineers’ travel, lodging and daily allowance. Our after-sales team handles enquiries. Payment is 30% by T/T on signing, 65% by T/T before shipment and 5% after installation and commissioning, or L/C at sight; prices are quoted ex-works (EXW).
Anonymised reference deliveries
Our lines have gone to 25 countries — most make construction tube, and others run fire-extinguisher tube, furniture tube and other sections.
The two lines side by side
| Purlin roll forming | Direct forming square | |
|---|---|---|
| Product | Open C / Z / Ω section | Closed square and rectangular tube |
| Joining | None — cold forming only | High-frequency welded |
| Size change | Stepless adjustment, no roll change | Combined mould with servo adjustment |
| Material or wall | 2–4 mm material | 1.5–20 mm wall across seven bands |
| Size window | C / Z / Ω profiles | 30 × 30 – 500 × 500 mm |
| Speed | Up to 20 m/min forming | Not published |
Roll forming operation in sheet metal
Because the purlin line has no welding at all, two things that matter on a tube mill do not apply to it.
There is no welder power figure, because there is no welder. There is no weld seam to inspect, because there is no seam.
How the two lines differ
The purlin line’s strengths are bearing-steel hardened rolls, Cr12 hardened dies and cutters, and stepless adjustment without a roll change. The direct-forming line answers a different question: removing the roll change from a welded closed section.
What both share is the supply answer behind them. Rolls and key wear parts are machined in-house on our own CNC equipment, which reduces reliance on outsourced tooling and is the reason lead time, cost and consistency stay controllable.
Send the profile drawing, material thickness and grade, and the size spread you expect to run. For the purlin line, add hole pitch and length range; for direct forming, add the square sizes and wall you need.
Purlin Machine Lines
Pipe Production Applications
Large Diameter Tube Mill
High-Frequency Welded Pipe MillSend Your Enquiry
Tell us the pipe outside-diameter range, the wall thickness and the output you need. An engineer reads every enquiry — it does not land in a general sales inbox.